Paul D. Hain, MD

Many pediatric hospitalizations are of short duration, and more than half of short‐stay hospitalizations are designated as observation status.[1, 2] Observation status is an administrative label assigned to patients who do not meet hospital or payer criteria for inpatient‐status care. Short‐stay observation‐status patients do not fit in traditional models of emergency department (ED) or inpatient care. EDs often focus on discharging or admitting patients within a matter of hours, whereas inpatient units tend to measure length of stay (LOS) in terms of days[3] and may not have systems in place to facilitate rapid discharge of short‐stay patients.[4] Observation units (OUs) have been established in some hospitals to address the unique care needs of short‐stay patients.[5, 6, 7]

Single‐site reports from children's hospitals with successful OUs have demonstrated shorter LOS and lower costs compared with inpatient settings.[6, 8, 9, 10, 11, 12, 13, 14] No prior study has examined hospital‐level effects of an OU on observation‐status patient outcomes. The Pediatric Health Information System (PHIS) database provides a unique opportunity to explore this question, because unlike other national hospital administrative databases,[15, 16] the PHIS dataset contains information about children under observation status. In addition, we know which PHIS hospitals had a dedicated OU in 2011.⁷

We hypothesized that overall observation‐status stays in hospitals with a dedicated OU would be of shorter duration with earlier discharges at lower cost than observation‐status stays in hospitals without a dedicated OU. We compared hospitals with and without a dedicated OU on secondary outcomes including rates of conversion to inpatient status and return care for any reason.

METHODS

We conducted a cross‐sectional analysis of hospital administrative data using the 2011 PHIS databasea national administrative database that contains resource utilization data from 43 participating hospitals located in 26 states plus the District of Columbia. These hospitals account for approximately 20% of pediatric hospitalizations in the United States.

For each hospital encounter, PHIS includes patient demographics, up to 41 International Classification of Diseases, Ninth Revision, Clinical Modification (ICD‐9‐CM) diagnoses, up to 41 ICD‐9‐CM procedures, and hospital charges for services. Data are deidentified prior to inclusion, but unique identifiers allow for determination of return visits and readmissions following an index visit for an individual patient. Data quality and reliability are assured jointly by the Children's Hospital Association (formerly Child Health Corporation of America, Overland Park, KS), participating hospitals, and Truven Health Analytics (New York, NY). This study, using administrative data, was not considered human subjects research by the policies of the Cincinnati Children's Hospital Medical Center Institutional Review Board.

RESULTS

Hospital Characteristics

Dedicated OUs were present in 14 of the 31 hospitals that reported observation‐status patient data to PHIS (Figure 1). Three of these hospitals had OUs that were open for 5 months or less in 2011; 1 unit opened, 1 unit closed, and 1 hospital operated a seasonal unit. The remaining 17 hospitals reported no OU that admitted unscheduled patients from the ED during 2011. Hospitals with a dedicated OU had more inpatient beds and higher median number of inpatient admissions than those without (Table 1). Hospitals were statistically similar in terms of total volume of ED visits, percentage of ED visits resulting in admission, total number of observation‐status stays, percentage of admissions under observation status, and payer mix.

Figure 1

Table 1.Hospitals* With and Without Dedicated Observation Units

	Overall, Median (IQR)	Hospitals With a Dedicated Observation Unit, Median (IQR)	Hospitals Without a Dedicated Observation Unit, Median (IQR)	P Value
NOTE: Abbreviations: ED, emergency department; IQR, interquartile range. *Among hospitals that reported observation‐status patient data to the Pediatric Health Information System database in 2011. Hospitals reporting the presence of at least 1 dedicated observation unit that admitted unscheduled patients from the ED in 2011. Percent of ED visits resulting in admission=number of ED visits admitted to inpatient or observation status divided by total number of ED visits in 2011. Percent of admissions under observation status=number of observation‐status stays divided by the total number of admissions (observation and inpatient status) in 2011.
No. of hospitals	31	14	17
Total no. of inpatient beds	273 (213311)	304 (269425)	246 (175293)	0.006
Total no. ED visits	62971 (47,50497,723)	87,892 (55,102117,119)	53,151 (4750470,882)	0.21
ED visits resulting in admission, %	13.1 (9.715.0)	13.8 (10.5, 19.1)	12.5 (9.714.5)	0.31
Total no. of inpatient admissions	11,537 (9,26814,568)	13,206 (11,32517,869)	10,207 (8,64013,363)	0.04
Admissions under observation status, %	25.7 (19.733.8)	25.5 (21.431.4)	26.0 (16.935.1)	0.98
Total no. of observation stays	3,820 (27935672)	4,850 (3,309 6,196)	3,141 (2,3654,616)	0.07
Government payer, %	60.2 (53.371.2)	62.1 (54.9, 65.9)	59.2 (53.373.7)	0.89

DISCUSSION

Counter to our hypothesis, we did not find hospital‐level differences in length of stay or costs for observation‐status patients cared for in hospitals with and without a dedicated OU, though hospitals with dedicated OUs did have more same‐day discharges and more morning discharges. The lack of observed differences in LOS and costs may reflect the fact that many children under observation status are treated throughout the hospital, even in facilities with a dedicated OU. Access to a dedicated OU is limited by factors including small numbers of OU beds and specific low acuity/low complexity OU admission criteria.[7] The inclusion of all children admitted under observation status in our analyses may have diluted any effect of dedicated OUs at the hospital level, but was necessary due to the inability to identify location of care for children admitted under observation status. Location of care is an important variable that should be incorporated into administrative databases to allow for comparative effectiveness research designs. Until such data are available, chart review at individual hospitals would be necessary to determine which patients received care in an OU.

We did find that discharges for observation‐status patients occurred earlier in the day in hospitals with a dedicated OU when compared with observation‐status patients in hospitals without a dedicated OU. In addition, the percentage of same‐day discharges was higher among observation‐status patients treated in hospitals with a dedicated OU. These differences may stem from policies and procedures that encourage rapid discharge in dedicated OUs, and those practices may affect other care areas. For example, OUs may enforce policies requiring family presence at the bedside or utilize staffing models where doctors and nurses are in frequent communication, both of which would facilitate discharge as soon as a patient no longer required hospital‐based care.[7] A retrospective chart review study design could be used to identify discharge processes and other key characteristics of highly performing OUs.

We found conflicting results in our main and sensitivity analyses related to conversion to inpatient status. Lower percentages of observation‐status patients converting to inpatient status indicates greater success in the delivery of observation care based on established performance metrics.[19] Lower rates of conversion to inpatient status may be the result of stricter admission criteria for some diagnosis and in hospitals with a continuously open dedicate OU, more refined processes for utilization review that allow for patients to be placed into the correct status (observation vs inpatient) at the time of admission, or efforts to educate providers about the designation of observation status.[7] It is also possible that fewer observation‐status patients convert to inpatient status in hospitals with a continuously open dedicated OU because such a change would require movement of the patient to an inpatient bed.

These analyses were more comprehensive than our prior studies[2, 20] in that we included both patients who were treated first in the ED and those who were not. In addition to the APR‐DRGs representative of conditions that have been successfully treated in ED‐based pediatric OUs (eg, asthma, seizures, gastroenteritis, cellulitis),[8, 9, 21, 22] we found observation‐status was commonly associated with procedural care. This population of patients may be relevant to hospitalists who staff OUs that provide both unscheduled and postprocedural care. The colocation of medical and postprocedural patients has been described by others[8, 23] and was reported to occur in over half of the OUs included in this study.[7] The extent to which postprocedure observation care is provided in general OUs staffed by hospitalists represents another opportunity for further study.

Hospitals face many considerations when determining if and how they will provide observation services to patients expected to experience short stays.[7] Some hospitals may be unable to justify an OU for all or part of the year based on the volume of admissions or the costs to staff an OU.[24, 25] Other hospitals may open an OU to promote patient flow and reduce ED crowding.[26] Hospitals may also be influenced by reimbursement policies related to observation‐status stays. Although we did not observe differences in overall payer mix, we did find higher percentages of observation‐status patients in hospitals with dedicated OUs to have public insurance. Although hospital contracts with payers around observation status patients are complex and beyond the scope of this analysis, it is possible that hospitals have established OUs because of increasingly stringent rules or criteria to meet inpatient status or experiences with high volumes of observation‐status patients covered by a particular payer. Nevertheless, the brief nature of many pediatric hospitalizations and the scarcity of pediatric OU beds must be considered in policy changes that result from national discussions about the appropriateness of inpatient stays shorter than 2 nights in duration.[27]

CONCLUSION

Observation status patients are similar in hospitals with and without dedicated observation units that admit children from the ED. The presence of a dedicated OU appears to have an influence on same‐day and morning discharges across all observation‐status stays without impacting other hospital‐level outcomes. Inclusion of location of care (eg, geographically distinct dedicated OU vs general inpatient unit vs ED) in hospital administrative datasets would allow for meaningful comparisons of different models of care for short‐stay observation‐status patients.

Many pediatric hospitalizations are of short duration, and more than half of short‐stay hospitalizations are designated as observation status.[1, 2] Observation status is an administrative label assigned to patients who do not meet hospital or payer criteria for inpatient‐status care. Short‐stay observation‐status patients do not fit in traditional models of emergency department (ED) or inpatient care. EDs often focus on discharging or admitting patients within a matter of hours, whereas inpatient units tend to measure length of stay (LOS) in terms of days[3] and may not have systems in place to facilitate rapid discharge of short‐stay patients.[4] Observation units (OUs) have been established in some hospitals to address the unique care needs of short‐stay patients.[5, 6, 7]

Single‐site reports from children's hospitals with successful OUs have demonstrated shorter LOS and lower costs compared with inpatient settings.[6, 8, 9, 10, 11, 12, 13, 14] No prior study has examined hospital‐level effects of an OU on observation‐status patient outcomes. The Pediatric Health Information System (PHIS) database provides a unique opportunity to explore this question, because unlike other national hospital administrative databases,[15, 16] the PHIS dataset contains information about children under observation status. In addition, we know which PHIS hospitals had a dedicated OU in 2011.⁷

We hypothesized that overall observation‐status stays in hospitals with a dedicated OU would be of shorter duration with earlier discharges at lower cost than observation‐status stays in hospitals without a dedicated OU. We compared hospitals with and without a dedicated OU on secondary outcomes including rates of conversion to inpatient status and return care for any reason.

METHODS

We conducted a cross‐sectional analysis of hospital administrative data using the 2011 PHIS databasea national administrative database that contains resource utilization data from 43 participating hospitals located in 26 states plus the District of Columbia. These hospitals account for approximately 20% of pediatric hospitalizations in the United States.

For each hospital encounter, PHIS includes patient demographics, up to 41 International Classification of Diseases, Ninth Revision, Clinical Modification (ICD‐9‐CM) diagnoses, up to 41 ICD‐9‐CM procedures, and hospital charges for services. Data are deidentified prior to inclusion, but unique identifiers allow for determination of return visits and readmissions following an index visit for an individual patient. Data quality and reliability are assured jointly by the Children's Hospital Association (formerly Child Health Corporation of America, Overland Park, KS), participating hospitals, and Truven Health Analytics (New York, NY). This study, using administrative data, was not considered human subjects research by the policies of the Cincinnati Children's Hospital Medical Center Institutional Review Board.

RESULTS

Hospital Characteristics

Dedicated OUs were present in 14 of the 31 hospitals that reported observation‐status patient data to PHIS (Figure 1). Three of these hospitals had OUs that were open for 5 months or less in 2011; 1 unit opened, 1 unit closed, and 1 hospital operated a seasonal unit. The remaining 17 hospitals reported no OU that admitted unscheduled patients from the ED during 2011. Hospitals with a dedicated OU had more inpatient beds and higher median number of inpatient admissions than those without (Table 1). Hospitals were statistically similar in terms of total volume of ED visits, percentage of ED visits resulting in admission, total number of observation‐status stays, percentage of admissions under observation status, and payer mix.

Figure 1

Table 1.Hospitals* With and Without Dedicated Observation Units

	Overall, Median (IQR)	Hospitals With a Dedicated Observation Unit, Median (IQR)	Hospitals Without a Dedicated Observation Unit, Median (IQR)	P Value
NOTE: Abbreviations: ED, emergency department; IQR, interquartile range. *Among hospitals that reported observation‐status patient data to the Pediatric Health Information System database in 2011. Hospitals reporting the presence of at least 1 dedicated observation unit that admitted unscheduled patients from the ED in 2011. Percent of ED visits resulting in admission=number of ED visits admitted to inpatient or observation status divided by total number of ED visits in 2011. Percent of admissions under observation status=number of observation‐status stays divided by the total number of admissions (observation and inpatient status) in 2011.
No. of hospitals	31	14	17
Total no. of inpatient beds	273 (213311)	304 (269425)	246 (175293)	0.006
Total no. ED visits	62971 (47,50497,723)	87,892 (55,102117,119)	53,151 (4750470,882)	0.21
ED visits resulting in admission, %	13.1 (9.715.0)	13.8 (10.5, 19.1)	12.5 (9.714.5)	0.31
Total no. of inpatient admissions	11,537 (9,26814,568)	13,206 (11,32517,869)	10,207 (8,64013,363)	0.04
Admissions under observation status, %	25.7 (19.733.8)	25.5 (21.431.4)	26.0 (16.935.1)	0.98
Total no. of observation stays	3,820 (27935672)	4,850 (3,309 6,196)	3,141 (2,3654,616)	0.07
Government payer, %	60.2 (53.371.2)	62.1 (54.9, 65.9)	59.2 (53.373.7)	0.89

DISCUSSION

Counter to our hypothesis, we did not find hospital‐level differences in length of stay or costs for observation‐status patients cared for in hospitals with and without a dedicated OU, though hospitals with dedicated OUs did have more same‐day discharges and more morning discharges. The lack of observed differences in LOS and costs may reflect the fact that many children under observation status are treated throughout the hospital, even in facilities with a dedicated OU. Access to a dedicated OU is limited by factors including small numbers of OU beds and specific low acuity/low complexity OU admission criteria.[7] The inclusion of all children admitted under observation status in our analyses may have diluted any effect of dedicated OUs at the hospital level, but was necessary due to the inability to identify location of care for children admitted under observation status. Location of care is an important variable that should be incorporated into administrative databases to allow for comparative effectiveness research designs. Until such data are available, chart review at individual hospitals would be necessary to determine which patients received care in an OU.

We did find that discharges for observation‐status patients occurred earlier in the day in hospitals with a dedicated OU when compared with observation‐status patients in hospitals without a dedicated OU. In addition, the percentage of same‐day discharges was higher among observation‐status patients treated in hospitals with a dedicated OU. These differences may stem from policies and procedures that encourage rapid discharge in dedicated OUs, and those practices may affect other care areas. For example, OUs may enforce policies requiring family presence at the bedside or utilize staffing models where doctors and nurses are in frequent communication, both of which would facilitate discharge as soon as a patient no longer required hospital‐based care.[7] A retrospective chart review study design could be used to identify discharge processes and other key characteristics of highly performing OUs.

We found conflicting results in our main and sensitivity analyses related to conversion to inpatient status. Lower percentages of observation‐status patients converting to inpatient status indicates greater success in the delivery of observation care based on established performance metrics.[19] Lower rates of conversion to inpatient status may be the result of stricter admission criteria for some diagnosis and in hospitals with a continuously open dedicate OU, more refined processes for utilization review that allow for patients to be placed into the correct status (observation vs inpatient) at the time of admission, or efforts to educate providers about the designation of observation status.[7] It is also possible that fewer observation‐status patients convert to inpatient status in hospitals with a continuously open dedicated OU because such a change would require movement of the patient to an inpatient bed.

These analyses were more comprehensive than our prior studies[2, 20] in that we included both patients who were treated first in the ED and those who were not. In addition to the APR‐DRGs representative of conditions that have been successfully treated in ED‐based pediatric OUs (eg, asthma, seizures, gastroenteritis, cellulitis),[8, 9, 21, 22] we found observation‐status was commonly associated with procedural care. This population of patients may be relevant to hospitalists who staff OUs that provide both unscheduled and postprocedural care. The colocation of medical and postprocedural patients has been described by others[8, 23] and was reported to occur in over half of the OUs included in this study.[7] The extent to which postprocedure observation care is provided in general OUs staffed by hospitalists represents another opportunity for further study.

Hospitals face many considerations when determining if and how they will provide observation services to patients expected to experience short stays.[7] Some hospitals may be unable to justify an OU for all or part of the year based on the volume of admissions or the costs to staff an OU.[24, 25] Other hospitals may open an OU to promote patient flow and reduce ED crowding.[26] Hospitals may also be influenced by reimbursement policies related to observation‐status stays. Although we did not observe differences in overall payer mix, we did find higher percentages of observation‐status patients in hospitals with dedicated OUs to have public insurance. Although hospital contracts with payers around observation status patients are complex and beyond the scope of this analysis, it is possible that hospitals have established OUs because of increasingly stringent rules or criteria to meet inpatient status or experiences with high volumes of observation‐status patients covered by a particular payer. Nevertheless, the brief nature of many pediatric hospitalizations and the scarcity of pediatric OU beds must be considered in policy changes that result from national discussions about the appropriateness of inpatient stays shorter than 2 nights in duration.[27]

CONCLUSION

Observation status patients are similar in hospitals with and without dedicated observation units that admit children from the ED. The presence of a dedicated OU appears to have an influence on same‐day and morning discharges across all observation‐status stays without impacting other hospital‐level outcomes. Inclusion of location of care (eg, geographically distinct dedicated OU vs general inpatient unit vs ED) in hospital administrative datasets would allow for meaningful comparisons of different models of care for short‐stay observation‐status patients.

Many pediatric hospitalizations are of short duration, and more than half of short‐stay hospitalizations are designated as observation status.[1, 2] Observation status is an administrative label assigned to patients who do not meet hospital or payer criteria for inpatient‐status care. Short‐stay observation‐status patients do not fit in traditional models of emergency department (ED) or inpatient care. EDs often focus on discharging or admitting patients within a matter of hours, whereas inpatient units tend to measure length of stay (LOS) in terms of days[3] and may not have systems in place to facilitate rapid discharge of short‐stay patients.[4] Observation units (OUs) have been established in some hospitals to address the unique care needs of short‐stay patients.[5, 6, 7]

Single‐site reports from children's hospitals with successful OUs have demonstrated shorter LOS and lower costs compared with inpatient settings.[6, 8, 9, 10, 11, 12, 13, 14] No prior study has examined hospital‐level effects of an OU on observation‐status patient outcomes. The Pediatric Health Information System (PHIS) database provides a unique opportunity to explore this question, because unlike other national hospital administrative databases,[15, 16] the PHIS dataset contains information about children under observation status. In addition, we know which PHIS hospitals had a dedicated OU in 2011.⁷

We hypothesized that overall observation‐status stays in hospitals with a dedicated OU would be of shorter duration with earlier discharges at lower cost than observation‐status stays in hospitals without a dedicated OU. We compared hospitals with and without a dedicated OU on secondary outcomes including rates of conversion to inpatient status and return care for any reason.

METHODS

We conducted a cross‐sectional analysis of hospital administrative data using the 2011 PHIS databasea national administrative database that contains resource utilization data from 43 participating hospitals located in 26 states plus the District of Columbia. These hospitals account for approximately 20% of pediatric hospitalizations in the United States.

For each hospital encounter, PHIS includes patient demographics, up to 41 International Classification of Diseases, Ninth Revision, Clinical Modification (ICD‐9‐CM) diagnoses, up to 41 ICD‐9‐CM procedures, and hospital charges for services. Data are deidentified prior to inclusion, but unique identifiers allow for determination of return visits and readmissions following an index visit for an individual patient. Data quality and reliability are assured jointly by the Children's Hospital Association (formerly Child Health Corporation of America, Overland Park, KS), participating hospitals, and Truven Health Analytics (New York, NY). This study, using administrative data, was not considered human subjects research by the policies of the Cincinnati Children's Hospital Medical Center Institutional Review Board.

RESULTS

Hospital Characteristics

Dedicated OUs were present in 14 of the 31 hospitals that reported observation‐status patient data to PHIS (Figure 1). Three of these hospitals had OUs that were open for 5 months or less in 2011; 1 unit opened, 1 unit closed, and 1 hospital operated a seasonal unit. The remaining 17 hospitals reported no OU that admitted unscheduled patients from the ED during 2011. Hospitals with a dedicated OU had more inpatient beds and higher median number of inpatient admissions than those without (Table 1). Hospitals were statistically similar in terms of total volume of ED visits, percentage of ED visits resulting in admission, total number of observation‐status stays, percentage of admissions under observation status, and payer mix.

Figure 1

Table 1.Hospitals* With and Without Dedicated Observation Units

	Overall, Median (IQR)	Hospitals With a Dedicated Observation Unit, Median (IQR)	Hospitals Without a Dedicated Observation Unit, Median (IQR)	P Value
NOTE: Abbreviations: ED, emergency department; IQR, interquartile range. *Among hospitals that reported observation‐status patient data to the Pediatric Health Information System database in 2011. Hospitals reporting the presence of at least 1 dedicated observation unit that admitted unscheduled patients from the ED in 2011. Percent of ED visits resulting in admission=number of ED visits admitted to inpatient or observation status divided by total number of ED visits in 2011. Percent of admissions under observation status=number of observation‐status stays divided by the total number of admissions (observation and inpatient status) in 2011.
No. of hospitals	31	14	17
Total no. of inpatient beds	273 (213311)	304 (269425)	246 (175293)	0.006
Total no. ED visits	62971 (47,50497,723)	87,892 (55,102117,119)	53,151 (4750470,882)	0.21
ED visits resulting in admission, %	13.1 (9.715.0)	13.8 (10.5, 19.1)	12.5 (9.714.5)	0.31
Total no. of inpatient admissions	11,537 (9,26814,568)	13,206 (11,32517,869)	10,207 (8,64013,363)	0.04
Admissions under observation status, %	25.7 (19.733.8)	25.5 (21.431.4)	26.0 (16.935.1)	0.98
Total no. of observation stays	3,820 (27935672)	4,850 (3,309 6,196)	3,141 (2,3654,616)	0.07
Government payer, %	60.2 (53.371.2)	62.1 (54.9, 65.9)	59.2 (53.373.7)	0.89

DISCUSSION

Counter to our hypothesis, we did not find hospital‐level differences in length of stay or costs for observation‐status patients cared for in hospitals with and without a dedicated OU, though hospitals with dedicated OUs did have more same‐day discharges and more morning discharges. The lack of observed differences in LOS and costs may reflect the fact that many children under observation status are treated throughout the hospital, even in facilities with a dedicated OU. Access to a dedicated OU is limited by factors including small numbers of OU beds and specific low acuity/low complexity OU admission criteria.[7] The inclusion of all children admitted under observation status in our analyses may have diluted any effect of dedicated OUs at the hospital level, but was necessary due to the inability to identify location of care for children admitted under observation status. Location of care is an important variable that should be incorporated into administrative databases to allow for comparative effectiveness research designs. Until such data are available, chart review at individual hospitals would be necessary to determine which patients received care in an OU.

We did find that discharges for observation‐status patients occurred earlier in the day in hospitals with a dedicated OU when compared with observation‐status patients in hospitals without a dedicated OU. In addition, the percentage of same‐day discharges was higher among observation‐status patients treated in hospitals with a dedicated OU. These differences may stem from policies and procedures that encourage rapid discharge in dedicated OUs, and those practices may affect other care areas. For example, OUs may enforce policies requiring family presence at the bedside or utilize staffing models where doctors and nurses are in frequent communication, both of which would facilitate discharge as soon as a patient no longer required hospital‐based care.[7] A retrospective chart review study design could be used to identify discharge processes and other key characteristics of highly performing OUs.

We found conflicting results in our main and sensitivity analyses related to conversion to inpatient status. Lower percentages of observation‐status patients converting to inpatient status indicates greater success in the delivery of observation care based on established performance metrics.[19] Lower rates of conversion to inpatient status may be the result of stricter admission criteria for some diagnosis and in hospitals with a continuously open dedicate OU, more refined processes for utilization review that allow for patients to be placed into the correct status (observation vs inpatient) at the time of admission, or efforts to educate providers about the designation of observation status.[7] It is also possible that fewer observation‐status patients convert to inpatient status in hospitals with a continuously open dedicated OU because such a change would require movement of the patient to an inpatient bed.

These analyses were more comprehensive than our prior studies[2, 20] in that we included both patients who were treated first in the ED and those who were not. In addition to the APR‐DRGs representative of conditions that have been successfully treated in ED‐based pediatric OUs (eg, asthma, seizures, gastroenteritis, cellulitis),[8, 9, 21, 22] we found observation‐status was commonly associated with procedural care. This population of patients may be relevant to hospitalists who staff OUs that provide both unscheduled and postprocedural care. The colocation of medical and postprocedural patients has been described by others[8, 23] and was reported to occur in over half of the OUs included in this study.[7] The extent to which postprocedure observation care is provided in general OUs staffed by hospitalists represents another opportunity for further study.

Hospitals face many considerations when determining if and how they will provide observation services to patients expected to experience short stays.[7] Some hospitals may be unable to justify an OU for all or part of the year based on the volume of admissions or the costs to staff an OU.[24, 25] Other hospitals may open an OU to promote patient flow and reduce ED crowding.[26] Hospitals may also be influenced by reimbursement policies related to observation‐status stays. Although we did not observe differences in overall payer mix, we did find higher percentages of observation‐status patients in hospitals with dedicated OUs to have public insurance. Although hospital contracts with payers around observation status patients are complex and beyond the scope of this analysis, it is possible that hospitals have established OUs because of increasingly stringent rules or criteria to meet inpatient status or experiences with high volumes of observation‐status patients covered by a particular payer. Nevertheless, the brief nature of many pediatric hospitalizations and the scarcity of pediatric OU beds must be considered in policy changes that result from national discussions about the appropriateness of inpatient stays shorter than 2 nights in duration.[27]

CONCLUSION

Observation status patients are similar in hospitals with and without dedicated observation units that admit children from the ED. The presence of a dedicated OU appears to have an influence on same‐day and morning discharges across all observation‐status stays without impacting other hospital‐level outcomes. Inclusion of location of care (eg, geographically distinct dedicated OU vs general inpatient unit vs ED) in hospital administrative datasets would allow for meaningful comparisons of different models of care for short‐stay observation‐status patients.

Urinary tract infections (UTIs) are one of the most common reasons for pediatric hospitalizations.1 Bacterial infections require prompt treatment with appropriate antimicrobial agents. Results from culture and susceptibility testing, however, are often unavailable until 48 hours after initial presentation. Therefore, the clinician must select antimicrobials empirically, basing decisions on likely pathogens and local resistance patterns.2 This decision is challenging because the effect of treatment delay on clinical outcomes is difficult to determine and resistance among uropathogens is increasing. Resistance rates have doubled over the past several years.3, 4 For common first‐line antibiotics, such as ampicillin and trimethoprim‐sulfamethoxazole, resistance rates for Escherichia coli, the most common uropathogen, exceed 25%.4, 5 While resistance to third‐generation cephalosporins remains low, rates in the United States have increased from <1% in 1999 to 4% in 2010. International data shows much higher resistance rates for cephalosporins in general.6, 7 This high prevalence of resistance may prompt the use of broad‐spectrum antibiotics for patients with UTI. For example, the use of third‐generation cephalosporins for UTI has doubled in recent years.3 Untreated, UTIs can lead to serious illness, but the consequences of inadequate initial antibiotic coverage are unknown.8, 9

Discordant antibiotic therapy, initial antibiotic therapy to which the causative bacterium is not susceptible, occurs in up to 9% of children hospitalized for UTI.10 However, there is reason to believe that discordant therapy may matter less for UTIs than for infections at other sites. First, in adults hospitalized with UTIs, discordant initial therapy did not affect the time to resolution of symptoms.11, 12 Second, most antibiotics used to treat UTIs are renally excreted and, thus, antibiotic concentrations at the site of infection are higher than can be achieved in the serum or cerebrospinal fluid.13 The Clinical and Laboratory Standard Institute has acknowledged that traditional susceptibility breakpoints may be too conservative for some non‐central nervous system infections; such as non‐central nervous system infections caused by Streptococcus pneumoniae.14

As resistance rates increase, more patients are likely to be treated with discordant therapy. Therefore, we sought to identify the clinical consequences of discordant antimicrobial therapy for patients hospitalized with a UTI.

METHODS

RESULTS

Of the initial 460 cases with positive urine culture growth at any time during admission, 216 met inclusion criteria for a laboratory‐confirmed UTI from urine culture completed at admission. The median age was 2.46 years (IQR: 0.27,8.89). In the study population, 25.0% were male, 31.0% were receiving prophylactic antibiotics, 13.0% had any grade of VUR, and 16.7% had abnormal GU anatomy (Table 1). A total of 82.4% of patients were treated with concordant initial therapy, 10.2% with discordant initial therapy, and 7.4% received delayed initial antibiotic therapy. There were no significant differences between the groups for any of the covariates. Discordant antibiotic cases ranged from 4.9% to 21.7% across hospitals.

The most common causative organisms were E. coli (65.7%) and Klebsiella spp (9.7%) (Table 2). The most common initial antibiotics were a third‐generation cephalosporin (39.1%), combination of ampicillin and a third‐ or fourth‐generation cephalosporin (16.7%), and combination of ampicillin with gentamicin (11.1%). A third‐generation cephalosporin was the initial antibiotic for 46.1% of the E. coli and 56.9% of Klebsiella spp UTIs. Resistance to third‐generation cephalosporins but carbapenem susceptibility was noted for 4.5% of E. coli and 7.7% of Klebsiella spp isolates. Patients with UTIs caused by Klebsiella spp, mixed organisms, and Enterobacter spp were more likely to receive discordant antibiotic therapy. Patients with Enterobacter spp and mixed‐organism UTIs were more likely to have delayed antibiotic therapy. Nineteen patients (8.8%) had positive blood cultures. Fifteen (6.9%) required intensive care unit (ICU) admission during hospitalization.

Unadjusted results are shown in Supporting Appendix 1, in the online version of this article. In the adjusted analysis, discordant antibiotic therapy was associated with a significantly longer LOS, compared with concordant therapy for all UTIs and for all UTIs caused by a single organism (Table 3). In adjusted analysis, discordant therapy was also associated with a 3.1 day (IQR: 2.0, 4.7) longer length of stay compared with concordant therapy for all E. coli UTIs.

Time to fever resolution was analyzed for patients with a documented fever at presentation for each treatment subgroup. One hundred thirty‐six patients were febrile at admission and 122 were febrile beyond the first recorded vital signs. Fever was present at admission in 60% of the concordant group and 55% of the discordant group (P = 0.6). The median duration of fever was 48 hours for the concordant group (n = 107; IQR: 24, 240) and 78 hours for the discordant group (n = 12; IQR: 48, 132). All patients were afebrile at discharge. Differences in fever duration between treatment groups were not statistically significant (P = 0.7).

DISCUSSION

Across 5 children's hospitals, 1 out of every 10 children hospitalized for UTI received discordant initial antibiotic therapy. Children receiving discordant antibiotic therapy had a 1.8 day longer LOS when compared with those on concordant therapy. However, there was no significant difference in time to fever resolution between the groups, suggesting that the increase in LOS was not explained by increased fever duration.

The overall rate of discordant therapy in this study is consistent with prior studies, as was the more common association of discordant therapy with non‐E. coli UTIs.10 According to the Kids' Inpatient Database 2009, there are 48,100 annual admissions for patients less than 20 years of age with a discharge diagnosis code of UTI in the United States.1 This suggests that nearly 4800 children with UTI could be affected by discordant therapy annually.

Children treated with discordant antibiotic therapy had a significantly longer LOS compared to those treated with concordant therapy. However, differences in time to fever resolution between the groups were not statistically significant. While resolution of fever may suggest clinical improvement and adequate empiric therapy, the lack of association with antibiotic concordance was not unexpected, since the relationship between fever resolution, clinical improvement, and LOS is complex and thus challenging to measure.21 These results support the notion that fever resolution alone may not be an adequate measure of clinical response.

It is possible that variability in discharge decision‐making may contribute to increased length of stay. Some clinicians may delay a patient's discharge until complete resolution of symptoms or knowledge of susceptibilities, while others may discharge patients that are still febrile and/or still receiving empiric antibiotics. Evidence‐based guidelines that address the appropriate time to discharge a patient with UTI are lacking. The American Academy of Pediatrics provides recommendations for use of parenteral antibiotics and hospital admission for patients with UTI, but does not address discharge decision‐making or patient management in the setting of discordant antibiotic therapy.2, 21

This study must be interpreted in the context of several limitations. First, our primary and secondary outcomes, LOS and fever duration, were surrogate measures for clinical response. We were not able to measure all clinical factors that may contribute to LOS, such as the patient's ability to tolerate oral fluids and antibiotics. Also, there may have been too few patients to detect a clinically important difference in fever duration between the concordant and discordant groups, especially for individual organisms. Although we did find a significant difference in LOS between patients treated with concordant compared with discordant therapy, there may be residual confounding from unobserved differences. This confounding, in conjunction with the small sample size, may cause us to underestimate the magnitude of the difference in LOS resulting from discordant therapy. Second, short‐term outcomes such as ICU admission were not investigated in this study; however, the proportion of patients admitted to the ICU in our population was quite small, precluding its use as a meaningful outcome measure. Third, the potential benefits to patients who were not exposed to unnecessary antibiotics, or harm to those that were exposed, could not be measured. Finally, our study was obtained using data from 5 free‐standing tertiary care pediatric facilities, thereby limiting its generalizability to other settings. Still, our rates of prophylactic antibiotic use, VUR, and GU abnormalities are similar to others reported in tertiary care children's hospitals, and we accounted for these covariates in our model.2225

As the frequency of infections caused by resistant bacteria increase, so will the number of patients receiving discordant antibiotics for UTI, compounding the challenge of empiric antimicrobial selection. Further research is needed to better understand how discordant initial antibiotic therapy contributes to LOS and whether it is associated with adverse short‐ and long‐term clinical outcomes. Such research could also aid in weighing the risk of broader‐spectrum prescribing on antimicrobial resistance patterns. While we identified an association between discordant initial antibiotic therapy and LOS, we were unable to determine the ideal empiric antibiotic therapy for patients hospitalized with UTI. Further investigation is needed to inform local and national practice guidelines for empiric antibiotic selection in patients with UTIs. This may also be an opportunity to decrease discordant empiric antibiotic selection, perhaps through use of antibiograms that stratify patients based on known factors, to lead to more specific initial therapy.

CONCLUSIONS

This study demonstrates that discordant antibiotic selection for UTI at admission is associated with longer hospital stay, but not fever duration. The full clinical consequences of discordant therapy, and the effects on length of stay, need to be better understood. Our findings, taken in combination with careful consideration of patient characteristics and prior history, may provide an opportunity to improve the hospital care for patients with UTIs.

Urinary tract infections (UTIs) are one of the most common reasons for pediatric hospitalizations.1 Bacterial infections require prompt treatment with appropriate antimicrobial agents. Results from culture and susceptibility testing, however, are often unavailable until 48 hours after initial presentation. Therefore, the clinician must select antimicrobials empirically, basing decisions on likely pathogens and local resistance patterns.2 This decision is challenging because the effect of treatment delay on clinical outcomes is difficult to determine and resistance among uropathogens is increasing. Resistance rates have doubled over the past several years.3, 4 For common first‐line antibiotics, such as ampicillin and trimethoprim‐sulfamethoxazole, resistance rates for Escherichia coli, the most common uropathogen, exceed 25%.4, 5 While resistance to third‐generation cephalosporins remains low, rates in the United States have increased from <1% in 1999 to 4% in 2010. International data shows much higher resistance rates for cephalosporins in general.6, 7 This high prevalence of resistance may prompt the use of broad‐spectrum antibiotics for patients with UTI. For example, the use of third‐generation cephalosporins for UTI has doubled in recent years.3 Untreated, UTIs can lead to serious illness, but the consequences of inadequate initial antibiotic coverage are unknown.8, 9

Discordant antibiotic therapy, initial antibiotic therapy to which the causative bacterium is not susceptible, occurs in up to 9% of children hospitalized for UTI.10 However, there is reason to believe that discordant therapy may matter less for UTIs than for infections at other sites. First, in adults hospitalized with UTIs, discordant initial therapy did not affect the time to resolution of symptoms.11, 12 Second, most antibiotics used to treat UTIs are renally excreted and, thus, antibiotic concentrations at the site of infection are higher than can be achieved in the serum or cerebrospinal fluid.13 The Clinical and Laboratory Standard Institute has acknowledged that traditional susceptibility breakpoints may be too conservative for some non‐central nervous system infections; such as non‐central nervous system infections caused by Streptococcus pneumoniae.14

As resistance rates increase, more patients are likely to be treated with discordant therapy. Therefore, we sought to identify the clinical consequences of discordant antimicrobial therapy for patients hospitalized with a UTI.

METHODS

RESULTS

Of the initial 460 cases with positive urine culture growth at any time during admission, 216 met inclusion criteria for a laboratory‐confirmed UTI from urine culture completed at admission. The median age was 2.46 years (IQR: 0.27,8.89). In the study population, 25.0% were male, 31.0% were receiving prophylactic antibiotics, 13.0% had any grade of VUR, and 16.7% had abnormal GU anatomy (Table 1). A total of 82.4% of patients were treated with concordant initial therapy, 10.2% with discordant initial therapy, and 7.4% received delayed initial antibiotic therapy. There were no significant differences between the groups for any of the covariates. Discordant antibiotic cases ranged from 4.9% to 21.7% across hospitals.

The most common causative organisms were E. coli (65.7%) and Klebsiella spp (9.7%) (Table 2). The most common initial antibiotics were a third‐generation cephalosporin (39.1%), combination of ampicillin and a third‐ or fourth‐generation cephalosporin (16.7%), and combination of ampicillin with gentamicin (11.1%). A third‐generation cephalosporin was the initial antibiotic for 46.1% of the E. coli and 56.9% of Klebsiella spp UTIs. Resistance to third‐generation cephalosporins but carbapenem susceptibility was noted for 4.5% of E. coli and 7.7% of Klebsiella spp isolates. Patients with UTIs caused by Klebsiella spp, mixed organisms, and Enterobacter spp were more likely to receive discordant antibiotic therapy. Patients with Enterobacter spp and mixed‐organism UTIs were more likely to have delayed antibiotic therapy. Nineteen patients (8.8%) had positive blood cultures. Fifteen (6.9%) required intensive care unit (ICU) admission during hospitalization.

Unadjusted results are shown in Supporting Appendix 1, in the online version of this article. In the adjusted analysis, discordant antibiotic therapy was associated with a significantly longer LOS, compared with concordant therapy for all UTIs and for all UTIs caused by a single organism (Table 3). In adjusted analysis, discordant therapy was also associated with a 3.1 day (IQR: 2.0, 4.7) longer length of stay compared with concordant therapy for all E. coli UTIs.

Time to fever resolution was analyzed for patients with a documented fever at presentation for each treatment subgroup. One hundred thirty‐six patients were febrile at admission and 122 were febrile beyond the first recorded vital signs. Fever was present at admission in 60% of the concordant group and 55% of the discordant group (P = 0.6). The median duration of fever was 48 hours for the concordant group (n = 107; IQR: 24, 240) and 78 hours for the discordant group (n = 12; IQR: 48, 132). All patients were afebrile at discharge. Differences in fever duration between treatment groups were not statistically significant (P = 0.7).

DISCUSSION

Across 5 children's hospitals, 1 out of every 10 children hospitalized for UTI received discordant initial antibiotic therapy. Children receiving discordant antibiotic therapy had a 1.8 day longer LOS when compared with those on concordant therapy. However, there was no significant difference in time to fever resolution between the groups, suggesting that the increase in LOS was not explained by increased fever duration.

The overall rate of discordant therapy in this study is consistent with prior studies, as was the more common association of discordant therapy with non‐E. coli UTIs.10 According to the Kids' Inpatient Database 2009, there are 48,100 annual admissions for patients less than 20 years of age with a discharge diagnosis code of UTI in the United States.1 This suggests that nearly 4800 children with UTI could be affected by discordant therapy annually.

Children treated with discordant antibiotic therapy had a significantly longer LOS compared to those treated with concordant therapy. However, differences in time to fever resolution between the groups were not statistically significant. While resolution of fever may suggest clinical improvement and adequate empiric therapy, the lack of association with antibiotic concordance was not unexpected, since the relationship between fever resolution, clinical improvement, and LOS is complex and thus challenging to measure.21 These results support the notion that fever resolution alone may not be an adequate measure of clinical response.

It is possible that variability in discharge decision‐making may contribute to increased length of stay. Some clinicians may delay a patient's discharge until complete resolution of symptoms or knowledge of susceptibilities, while others may discharge patients that are still febrile and/or still receiving empiric antibiotics. Evidence‐based guidelines that address the appropriate time to discharge a patient with UTI are lacking. The American Academy of Pediatrics provides recommendations for use of parenteral antibiotics and hospital admission for patients with UTI, but does not address discharge decision‐making or patient management in the setting of discordant antibiotic therapy.2, 21

This study must be interpreted in the context of several limitations. First, our primary and secondary outcomes, LOS and fever duration, were surrogate measures for clinical response. We were not able to measure all clinical factors that may contribute to LOS, such as the patient's ability to tolerate oral fluids and antibiotics. Also, there may have been too few patients to detect a clinically important difference in fever duration between the concordant and discordant groups, especially for individual organisms. Although we did find a significant difference in LOS between patients treated with concordant compared with discordant therapy, there may be residual confounding from unobserved differences. This confounding, in conjunction with the small sample size, may cause us to underestimate the magnitude of the difference in LOS resulting from discordant therapy. Second, short‐term outcomes such as ICU admission were not investigated in this study; however, the proportion of patients admitted to the ICU in our population was quite small, precluding its use as a meaningful outcome measure. Third, the potential benefits to patients who were not exposed to unnecessary antibiotics, or harm to those that were exposed, could not be measured. Finally, our study was obtained using data from 5 free‐standing tertiary care pediatric facilities, thereby limiting its generalizability to other settings. Still, our rates of prophylactic antibiotic use, VUR, and GU abnormalities are similar to others reported in tertiary care children's hospitals, and we accounted for these covariates in our model.2225

As the frequency of infections caused by resistant bacteria increase, so will the number of patients receiving discordant antibiotics for UTI, compounding the challenge of empiric antimicrobial selection. Further research is needed to better understand how discordant initial antibiotic therapy contributes to LOS and whether it is associated with adverse short‐ and long‐term clinical outcomes. Such research could also aid in weighing the risk of broader‐spectrum prescribing on antimicrobial resistance patterns. While we identified an association between discordant initial antibiotic therapy and LOS, we were unable to determine the ideal empiric antibiotic therapy for patients hospitalized with UTI. Further investigation is needed to inform local and national practice guidelines for empiric antibiotic selection in patients with UTIs. This may also be an opportunity to decrease discordant empiric antibiotic selection, perhaps through use of antibiograms that stratify patients based on known factors, to lead to more specific initial therapy.

CONCLUSIONS

This study demonstrates that discordant antibiotic selection for UTI at admission is associated with longer hospital stay, but not fever duration. The full clinical consequences of discordant therapy, and the effects on length of stay, need to be better understood. Our findings, taken in combination with careful consideration of patient characteristics and prior history, may provide an opportunity to improve the hospital care for patients with UTIs.

Urinary tract infections (UTIs) are one of the most common reasons for pediatric hospitalizations.1 Bacterial infections require prompt treatment with appropriate antimicrobial agents. Results from culture and susceptibility testing, however, are often unavailable until 48 hours after initial presentation. Therefore, the clinician must select antimicrobials empirically, basing decisions on likely pathogens and local resistance patterns.2 This decision is challenging because the effect of treatment delay on clinical outcomes is difficult to determine and resistance among uropathogens is increasing. Resistance rates have doubled over the past several years.3, 4 For common first‐line antibiotics, such as ampicillin and trimethoprim‐sulfamethoxazole, resistance rates for Escherichia coli, the most common uropathogen, exceed 25%.4, 5 While resistance to third‐generation cephalosporins remains low, rates in the United States have increased from <1% in 1999 to 4% in 2010. International data shows much higher resistance rates for cephalosporins in general.6, 7 This high prevalence of resistance may prompt the use of broad‐spectrum antibiotics for patients with UTI. For example, the use of third‐generation cephalosporins for UTI has doubled in recent years.3 Untreated, UTIs can lead to serious illness, but the consequences of inadequate initial antibiotic coverage are unknown.8, 9

Discordant antibiotic therapy, initial antibiotic therapy to which the causative bacterium is not susceptible, occurs in up to 9% of children hospitalized for UTI.10 However, there is reason to believe that discordant therapy may matter less for UTIs than for infections at other sites. First, in adults hospitalized with UTIs, discordant initial therapy did not affect the time to resolution of symptoms.11, 12 Second, most antibiotics used to treat UTIs are renally excreted and, thus, antibiotic concentrations at the site of infection are higher than can be achieved in the serum or cerebrospinal fluid.13 The Clinical and Laboratory Standard Institute has acknowledged that traditional susceptibility breakpoints may be too conservative for some non‐central nervous system infections; such as non‐central nervous system infections caused by Streptococcus pneumoniae.14

As resistance rates increase, more patients are likely to be treated with discordant therapy. Therefore, we sought to identify the clinical consequences of discordant antimicrobial therapy for patients hospitalized with a UTI.

METHODS

RESULTS

Of the initial 460 cases with positive urine culture growth at any time during admission, 216 met inclusion criteria for a laboratory‐confirmed UTI from urine culture completed at admission. The median age was 2.46 years (IQR: 0.27,8.89). In the study population, 25.0% were male, 31.0% were receiving prophylactic antibiotics, 13.0% had any grade of VUR, and 16.7% had abnormal GU anatomy (Table 1). A total of 82.4% of patients were treated with concordant initial therapy, 10.2% with discordant initial therapy, and 7.4% received delayed initial antibiotic therapy. There were no significant differences between the groups for any of the covariates. Discordant antibiotic cases ranged from 4.9% to 21.7% across hospitals.

The most common causative organisms were E. coli (65.7%) and Klebsiella spp (9.7%) (Table 2). The most common initial antibiotics were a third‐generation cephalosporin (39.1%), combination of ampicillin and a third‐ or fourth‐generation cephalosporin (16.7%), and combination of ampicillin with gentamicin (11.1%). A third‐generation cephalosporin was the initial antibiotic for 46.1% of the E. coli and 56.9% of Klebsiella spp UTIs. Resistance to third‐generation cephalosporins but carbapenem susceptibility was noted for 4.5% of E. coli and 7.7% of Klebsiella spp isolates. Patients with UTIs caused by Klebsiella spp, mixed organisms, and Enterobacter spp were more likely to receive discordant antibiotic therapy. Patients with Enterobacter spp and mixed‐organism UTIs were more likely to have delayed antibiotic therapy. Nineteen patients (8.8%) had positive blood cultures. Fifteen (6.9%) required intensive care unit (ICU) admission during hospitalization.

Unadjusted results are shown in Supporting Appendix 1, in the online version of this article. In the adjusted analysis, discordant antibiotic therapy was associated with a significantly longer LOS, compared with concordant therapy for all UTIs and for all UTIs caused by a single organism (Table 3). In adjusted analysis, discordant therapy was also associated with a 3.1 day (IQR: 2.0, 4.7) longer length of stay compared with concordant therapy for all E. coli UTIs.

Time to fever resolution was analyzed for patients with a documented fever at presentation for each treatment subgroup. One hundred thirty‐six patients were febrile at admission and 122 were febrile beyond the first recorded vital signs. Fever was present at admission in 60% of the concordant group and 55% of the discordant group (P = 0.6). The median duration of fever was 48 hours for the concordant group (n = 107; IQR: 24, 240) and 78 hours for the discordant group (n = 12; IQR: 48, 132). All patients were afebrile at discharge. Differences in fever duration between treatment groups were not statistically significant (P = 0.7).

DISCUSSION

Across 5 children's hospitals, 1 out of every 10 children hospitalized for UTI received discordant initial antibiotic therapy. Children receiving discordant antibiotic therapy had a 1.8 day longer LOS when compared with those on concordant therapy. However, there was no significant difference in time to fever resolution between the groups, suggesting that the increase in LOS was not explained by increased fever duration.

The overall rate of discordant therapy in this study is consistent with prior studies, as was the more common association of discordant therapy with non‐E. coli UTIs.10 According to the Kids' Inpatient Database 2009, there are 48,100 annual admissions for patients less than 20 years of age with a discharge diagnosis code of UTI in the United States.1 This suggests that nearly 4800 children with UTI could be affected by discordant therapy annually.

Children treated with discordant antibiotic therapy had a significantly longer LOS compared to those treated with concordant therapy. However, differences in time to fever resolution between the groups were not statistically significant. While resolution of fever may suggest clinical improvement and adequate empiric therapy, the lack of association with antibiotic concordance was not unexpected, since the relationship between fever resolution, clinical improvement, and LOS is complex and thus challenging to measure.21 These results support the notion that fever resolution alone may not be an adequate measure of clinical response.

It is possible that variability in discharge decision‐making may contribute to increased length of stay. Some clinicians may delay a patient's discharge until complete resolution of symptoms or knowledge of susceptibilities, while others may discharge patients that are still febrile and/or still receiving empiric antibiotics. Evidence‐based guidelines that address the appropriate time to discharge a patient with UTI are lacking. The American Academy of Pediatrics provides recommendations for use of parenteral antibiotics and hospital admission for patients with UTI, but does not address discharge decision‐making or patient management in the setting of discordant antibiotic therapy.2, 21

This study must be interpreted in the context of several limitations. First, our primary and secondary outcomes, LOS and fever duration, were surrogate measures for clinical response. We were not able to measure all clinical factors that may contribute to LOS, such as the patient's ability to tolerate oral fluids and antibiotics. Also, there may have been too few patients to detect a clinically important difference in fever duration between the concordant and discordant groups, especially for individual organisms. Although we did find a significant difference in LOS between patients treated with concordant compared with discordant therapy, there may be residual confounding from unobserved differences. This confounding, in conjunction with the small sample size, may cause us to underestimate the magnitude of the difference in LOS resulting from discordant therapy. Second, short‐term outcomes such as ICU admission were not investigated in this study; however, the proportion of patients admitted to the ICU in our population was quite small, precluding its use as a meaningful outcome measure. Third, the potential benefits to patients who were not exposed to unnecessary antibiotics, or harm to those that were exposed, could not be measured. Finally, our study was obtained using data from 5 free‐standing tertiary care pediatric facilities, thereby limiting its generalizability to other settings. Still, our rates of prophylactic antibiotic use, VUR, and GU abnormalities are similar to others reported in tertiary care children's hospitals, and we accounted for these covariates in our model.2225

As the frequency of infections caused by resistant bacteria increase, so will the number of patients receiving discordant antibiotics for UTI, compounding the challenge of empiric antimicrobial selection. Further research is needed to better understand how discordant initial antibiotic therapy contributes to LOS and whether it is associated with adverse short‐ and long‐term clinical outcomes. Such research could also aid in weighing the risk of broader‐spectrum prescribing on antimicrobial resistance patterns. While we identified an association between discordant initial antibiotic therapy and LOS, we were unable to determine the ideal empiric antibiotic therapy for patients hospitalized with UTI. Further investigation is needed to inform local and national practice guidelines for empiric antibiotic selection in patients with UTIs. This may also be an opportunity to decrease discordant empiric antibiotic selection, perhaps through use of antibiograms that stratify patients based on known factors, to lead to more specific initial therapy.

CONCLUSIONS

This study demonstrates that discordant antibiotic selection for UTI at admission is associated with longer hospital stay, but not fever duration. The full clinical consequences of discordant therapy, and the effects on length of stay, need to be better understood. Our findings, taken in combination with careful consideration of patient characteristics and prior history, may provide an opportunity to improve the hospital care for patients with UTIs.

In recent decades, hospital lengths of stay have decreased and there has been a shift toward outpatient management for many pediatric conditions. In 2003, one‐third of all children admitted to US hospitals experienced 1‐day inpatient stays, an increase from 19% in 1993.1 Some hospitals have developed dedicated observation units for the care of children, with select diagnoses, who are expected to respond to less than 24 hours of treatment.26 Expansion of observation services has been suggested as an approach to lessen emergency department (ED) crowding7 and alleviate high‐capacity conditions within hospital inpatient units.8

In contrast to care delivered in a dedicated observation unit, observation status is an administrative label applied to patients who do not meet inpatient criteria as defined by third parties such as InterQual. While the decision to admit a patient is ultimately at the discretion of the ordering physician, many hospitals use predetermined criteria to assign observation status to patients admitted to observation and inpatient units.9 Treatment provided under observation status is designated by hospitals and payers as outpatient care, even when delivered in an inpatient bed.10 As outpatient‐designated care, observation cases do not enter publicly available administrative datasets of hospital discharges that have traditionally been used to understand hospital resource utilization, including the National Hospital Discharge Survey and the Kid's Inpatient Database.11, 12

We hypothesize that there has been an increase in observation status care delivered to children in recent years, and that the majority of children under observation were discharged home without converting to inpatient status. To determine trends in pediatric observation status care, we conducted the first longitudinal, multicenter evaluation of observation status code utilization following ED treatment in a sample of US freestanding children's hospitals. In addition, we focused on the most recent year of data among top ranking diagnoses to assess the current state of observation status stay outcomes (including conversion to inpatient status and return visits).

METHODS

DATA ANALYSIS

For each of the 6 years of study, we calculated the following proportions to determine trends over time: 1) the number of Observation Status admissions from the ED as a proportion of the total number of ED visits resulting in Observation or Inpatient admission, and 2) the number of 1‐Day Stays admitted from the ED as a proportion of the total number of ED visits resulting in Observation or Inpatient admissions. Trends were analyzed using linear regression. Trends were also calculated for the total volume of admissions from the ED and the case‐mix index (CMI). CMI was assessed to evaluate for changes in the severity of illness for children admitted from the ED over the study period. Each hospital's CMI was calculated as an average of their Observation and Inpatient Status discharges' charge weights during the study period. Charge weights were calculated at the All Patient Refined Diagnosis Related Groups (APR‐DRG)/severity of illness level (3M Health Information Systems, St Paul, MN) and were normalized national average charges derived by Thomson‐Reuters from their Pediatric Projected National Database. Weights were then assigned to each discharge based on the discharge's APR‐DRG and severity level assignment.

To assess the current outcomes for observation, we analyzed stays with associated observation billing codes from the most recent year of available data (2009). Stays with Observation patient type were considered to have been discharged from observation, while those with an Inpatient Status patient type were considered to have converted to an inpatient admission during the observation period.

Using the 2009 data, we calculated descriptive statistics for patient characteristics (eg, age, gender, payer) comparing Observation Stays, 1‐Day Stays, and longer‐duration Inpatient admissions using chi‐square statistics. Age was categorized using the American Academy of Pediatrics groupings: <30 days, 30 days1 year, 12 years, 34 years, 512 years, 1317 years, >18 years. Designated payer was categorized into government, private, and other, including self‐pay and uninsured groups.

We used the Severity Classification Systems (SCS) developed for pediatric emergency care to estimate severity of illness for the visit.17 In this 5‐level system, each ICD‐9 diagnosis code is associated with a score related to the intensity of ED resources needed to care for a child with that diagnosis. In our analyses, each case was assigned the maximal SCS category based on the highest severity ICD‐9 code associated with the stay. Within the SCS, a score of 1 indicates minor illness (eg, diaper dermatitis) and 5 indicates major illness (eg, septic shock). The proportions of visits within categorical SCS scores were compared for Observation Stays, 1‐Day Stays, and longer‐duration Inpatient admissions using chi‐square statistics.

We determined the top 10 ranking diagnoses for which children were admitted from the ED in 2009 using the Diagnosis Grouping System (DGS).18 The DGS was designed specifically to categorize pediatric ED visits into clinically meaningful groups. The ICD‐9 code for the principal discharge diagnosis was used to assign records to 1 of the 77 DGS subgroups. Within each of the top ranking DGS subgroups, we determined the proportion of Observation Stays, 1‐Day Stays, and longer‐duration Inpatient admissions.

To provide clinically relevant outcomes of Observation Stays for common conditions, we selected stays with observation charges from within the top 10 ranking observation stay DGS subgroups in 2009. Outcomes for observation included: 1) immediate outcome of the observation stay (ie, discharge or conversion to inpatient status), 2) return visits to the ED in the 3 days following observation, and 3) readmissions to the hospital in the 3 and 30 days following observation. Bivariate comparisons of return visits and readmissions for Observation versus 1‐Day Stays within DGS subgroups were analyzed using chi‐square tests. Multivariate analyses of return visits and readmissions were conducted using Generalized Estimating Equations adjusting for severity of illness by SCS score and clustering by hospital. To account for local practice patterns, we also adjusted for a grouped treatment variable that included the site level proportion of children admitted to Observation Status, 1‐Day‐Stays, and longer Inpatient admissions. All statistical analyses were performed using SAS (version 9.2, SAS Institute, Inc, Cary, NC); P values <0.05 were considered statistically significant.

RESULTS

Trends in Short‐Stays

An increase in proportion of Observation Stays was mirrored by a decrease in proportion of 1‐Day Stays over the study period (Figure 1). In 2009, there were 1.4 times more Observation Stays than 1‐Day Stays (25,653 vs 18,425) compared with 14,242 and 20,747, respectively, in 2004. This shift toward more Observation Stays occurred as hospitals faced a 16% increase in the total number of admissions from the ED (91,318 to 108,217) and change in CMI from 1.48 to 1.51. Over the study period, roughly 40% of all admissions from the ED were Short‐Stays (Observation and 1‐Day Stays). Median LOS for Observation Status stays was 1 day (interquartile range [IQR]: 11).

Figure 1

DISCUSSION

In this first, multicenter longitudinal study of pediatric observation following an ED visit, we found that Observation Status code utilization has increased steadily over the past 6 years and, in 2007, the proportion of children admitted to observation status surpassed the proportion of children experiencing a 1‐day inpatient admission. Taken together, Short‐Stays made up more than 40% of the hospital‐based care delivered to children admitted from an ED. Stable trends in CMI over time suggest that observation status may be replacing inpatient status designated care for pediatric Short‐Stays in these hospitals. Our findings suggest the lines between outpatient observation and short‐stay inpatient care are becoming increasingly blurred. These trends have occurred in the setting of changing policies for hospital reimbursement, requirements for patients to meet criteria to qualify for inpatient admissions, and efforts to avoid stays deemed unnecessary or inappropriate by their brief duration.19 Therefore there is a growing need to understand the impact of children under observation on the structure, delivery, and financing of acute hospital care for children.

Our results also have implications for pediatric health services research that relies on hospital administrative databases that do not contain observation stays. Currently, observation stays are systematically excluded from many inpatient administrative datasets.11, 12 Analyses of datasets that do not account for observation stays likely result in underestimation of hospitalization rates and hospital resource utilization for children. This may be particularly important for high‐volume conditions, such as asthma and acute infections, for which children commonly require brief periods of hospital‐based care beyond an ED encounter. Data from pediatric observation status admissions should be consistently included in hospital administrative datasets to allow for more comprehensive analyses of hospital resource utilization among children.

Prior research has shown that the diagnoses commonly treated in pediatric observation units overlap with the diagnoses for which children experience 1‐Day Stays.1, 20 We found a similar pattern of conditions for which children were under Observation Status and 1‐Day Stays with comparable severity of illness between the groups in terms of SCS scores. Our findings imply a need to determine how and why hospitals differentiate Observation Status from 1‐Day‐Stay groups in order to improve the assignment of observation status. Assuming continued pressures from payers to provide more care in outpatient or observation settings, there is potential for expansion of dedicated observation services for children in the US. Without designated observation units or processes to group patients with lower severity conditions, there may be limited opportunities to realize more efficient hospital care simply through the application of the label of observation status.

For more than 30 years, observation services have been provided to children who require a period of monitoring to determine their response to therapy and the need for acute inpatient admission from the ED.21While we were not able to determine the location of care for observation status patients in this study, we know that few children's hospitals have dedicated observation units and, even when an observation unit is present, not all observation status patients are cared for in dedicated observation units.9 This, in essence, means that most children under observation status are cared for in virtual observation by inpatient teams using inpatient beds. If observation patients are treated in inpatient beds and consume the same resources as inpatients, then cost‐savings based on reimbursement contracts with payers may not reflect an actual reduction in services. Pediatric institutions will need to closely monitor the financial implications of observation status given the historical differences in payment for observation and inpatient care.

With more than 70% of children being discharged home following observation, our results are comparable to the published literature2, 5, 6, 22, 23 and guidelines for observation unit operations.24 Similar to prior studies,4, 15, 2530 our results also indicate that return visits and readmissions following observation are uncommon events. Our findings can serve as initial benchmarks for condition‐specific outcomes for pediatric observation care. Studies are needed both to identify the clinical characteristics predictive of successful discharge home from observation and to explore the hospital‐to‐hospital variability in outcomes for observation. Such studies are necessary to identify the most successful healthcare delivery models for pediatric observation stays.

LIMITATIONS

The primary limitation to our results is that data from a subset of freestanding children's hospitals may not reflect observation stays at other children's hospitals or the community hospitals that care for children across the US. Only 18 of 42 current PHIS member hospitals have provided both outpatient visit and inpatient stay data for each year of the study period and were considered eligible. In an effort to ensure the quality of observation stay data, we included the 16 hospitals that assigned observation charges to at least 90% of their observation status stays in the PHIS database. The exclusion of the 2 hospitals where <90% of observation status patients were assigned observation charges likely resulted in an underestimation of the utilization of observation status.

Second, there is potential for misclassification of patient type given institutional variations in the assignment of patient status. The PHIS database does not contain information about the factors that were considered in the assignment of observation status. At the time of admission from the ED, observation or inpatient status is assigned. While this decision is clearly reserved for the admitting physician, the process is not standardized across hospitals.9 Some institutions have Utilization Managers on site to help guide decision‐making, while others allow the assignment to be made by physicians without specific guidance. As a result, some patients may be assigned to observation status at admission and reassigned to inpatient status following Utilization Review, which may bias our results toward overestimation of the number of observation stays that converted to inpatient status.

The third limitation to our results relates to return visits. An accurate assessment of return visits is subject to the patient returning to the same hospital. If children do not return to the same hospital, our results would underestimate return visits and readmissions. In addition, we did not assess the reason for return visit as there was no way to verify if the return visit was truly related to the index visit without detailed chart review. Assuming children return to the same hospital for different reasons, our results would overestimate return visits associated with observation stays. We suspect that many 3‐day return visits result from the progression of acute illness or failure to respond to initial treatment, and 30‐day readmissions reflect recurrent hospital care needs related to chronic illnesses.

Lastly, severity classification is difficult when analyzing administrative datasets without physiologic patient data, and the SCS may not provide enough detail to reveal clinically important differences between patient groups.

CONCLUSIONS

Short‐stay hospitalizations following ED visits are common among children, and the majority of pediatric short‐stays are under observation status. Analyses of inpatient administrative databases that exclude observation stays likely result in an underestimation of hospital resource utilization for children. Efforts are needed to ensure that patients under observation status are accounted for in hospital administrative datasets used for pediatric health services research, and healthcare resource allocation, as it relates to hospital‐based care. While the clinical outcomes for observation patients appear favorable in terms of conversion to inpatient admissions and return visits, the financial implications of observation status care within children's hospitals are currently unknown.

In recent decades, hospital lengths of stay have decreased and there has been a shift toward outpatient management for many pediatric conditions. In 2003, one‐third of all children admitted to US hospitals experienced 1‐day inpatient stays, an increase from 19% in 1993.1 Some hospitals have developed dedicated observation units for the care of children, with select diagnoses, who are expected to respond to less than 24 hours of treatment.26 Expansion of observation services has been suggested as an approach to lessen emergency department (ED) crowding7 and alleviate high‐capacity conditions within hospital inpatient units.8

In contrast to care delivered in a dedicated observation unit, observation status is an administrative label applied to patients who do not meet inpatient criteria as defined by third parties such as InterQual. While the decision to admit a patient is ultimately at the discretion of the ordering physician, many hospitals use predetermined criteria to assign observation status to patients admitted to observation and inpatient units.9 Treatment provided under observation status is designated by hospitals and payers as outpatient care, even when delivered in an inpatient bed.10 As outpatient‐designated care, observation cases do not enter publicly available administrative datasets of hospital discharges that have traditionally been used to understand hospital resource utilization, including the National Hospital Discharge Survey and the Kid's Inpatient Database.11, 12

We hypothesize that there has been an increase in observation status care delivered to children in recent years, and that the majority of children under observation were discharged home without converting to inpatient status. To determine trends in pediatric observation status care, we conducted the first longitudinal, multicenter evaluation of observation status code utilization following ED treatment in a sample of US freestanding children's hospitals. In addition, we focused on the most recent year of data among top ranking diagnoses to assess the current state of observation status stay outcomes (including conversion to inpatient status and return visits).

METHODS

DATA ANALYSIS

For each of the 6 years of study, we calculated the following proportions to determine trends over time: 1) the number of Observation Status admissions from the ED as a proportion of the total number of ED visits resulting in Observation or Inpatient admission, and 2) the number of 1‐Day Stays admitted from the ED as a proportion of the total number of ED visits resulting in Observation or Inpatient admissions. Trends were analyzed using linear regression. Trends were also calculated for the total volume of admissions from the ED and the case‐mix index (CMI). CMI was assessed to evaluate for changes in the severity of illness for children admitted from the ED over the study period. Each hospital's CMI was calculated as an average of their Observation and Inpatient Status discharges' charge weights during the study period. Charge weights were calculated at the All Patient Refined Diagnosis Related Groups (APR‐DRG)/severity of illness level (3M Health Information Systems, St Paul, MN) and were normalized national average charges derived by Thomson‐Reuters from their Pediatric Projected National Database. Weights were then assigned to each discharge based on the discharge's APR‐DRG and severity level assignment.

To assess the current outcomes for observation, we analyzed stays with associated observation billing codes from the most recent year of available data (2009). Stays with Observation patient type were considered to have been discharged from observation, while those with an Inpatient Status patient type were considered to have converted to an inpatient admission during the observation period.

Using the 2009 data, we calculated descriptive statistics for patient characteristics (eg, age, gender, payer) comparing Observation Stays, 1‐Day Stays, and longer‐duration Inpatient admissions using chi‐square statistics. Age was categorized using the American Academy of Pediatrics groupings: <30 days, 30 days1 year, 12 years, 34 years, 512 years, 1317 years, >18 years. Designated payer was categorized into government, private, and other, including self‐pay and uninsured groups.

We used the Severity Classification Systems (SCS) developed for pediatric emergency care to estimate severity of illness for the visit.17 In this 5‐level system, each ICD‐9 diagnosis code is associated with a score related to the intensity of ED resources needed to care for a child with that diagnosis. In our analyses, each case was assigned the maximal SCS category based on the highest severity ICD‐9 code associated with the stay. Within the SCS, a score of 1 indicates minor illness (eg, diaper dermatitis) and 5 indicates major illness (eg, septic shock). The proportions of visits within categorical SCS scores were compared for Observation Stays, 1‐Day Stays, and longer‐duration Inpatient admissions using chi‐square statistics.

We determined the top 10 ranking diagnoses for which children were admitted from the ED in 2009 using the Diagnosis Grouping System (DGS).18 The DGS was designed specifically to categorize pediatric ED visits into clinically meaningful groups. The ICD‐9 code for the principal discharge diagnosis was used to assign records to 1 of the 77 DGS subgroups. Within each of the top ranking DGS subgroups, we determined the proportion of Observation Stays, 1‐Day Stays, and longer‐duration Inpatient admissions.

To provide clinically relevant outcomes of Observation Stays for common conditions, we selected stays with observation charges from within the top 10 ranking observation stay DGS subgroups in 2009. Outcomes for observation included: 1) immediate outcome of the observation stay (ie, discharge or conversion to inpatient status), 2) return visits to the ED in the 3 days following observation, and 3) readmissions to the hospital in the 3 and 30 days following observation. Bivariate comparisons of return visits and readmissions for Observation versus 1‐Day Stays within DGS subgroups were analyzed using chi‐square tests. Multivariate analyses of return visits and readmissions were conducted using Generalized Estimating Equations adjusting for severity of illness by SCS score and clustering by hospital. To account for local practice patterns, we also adjusted for a grouped treatment variable that included the site level proportion of children admitted to Observation Status, 1‐Day‐Stays, and longer Inpatient admissions. All statistical analyses were performed using SAS (version 9.2, SAS Institute, Inc, Cary, NC); P values <0.05 were considered statistically significant.

RESULTS

Trends in Short‐Stays

An increase in proportion of Observation Stays was mirrored by a decrease in proportion of 1‐Day Stays over the study period (Figure 1). In 2009, there were 1.4 times more Observation Stays than 1‐Day Stays (25,653 vs 18,425) compared with 14,242 and 20,747, respectively, in 2004. This shift toward more Observation Stays occurred as hospitals faced a 16% increase in the total number of admissions from the ED (91,318 to 108,217) and change in CMI from 1.48 to 1.51. Over the study period, roughly 40% of all admissions from the ED were Short‐Stays (Observation and 1‐Day Stays). Median LOS for Observation Status stays was 1 day (interquartile range [IQR]: 11).

Figure 1

DISCUSSION

In this first, multicenter longitudinal study of pediatric observation following an ED visit, we found that Observation Status code utilization has increased steadily over the past 6 years and, in 2007, the proportion of children admitted to observation status surpassed the proportion of children experiencing a 1‐day inpatient admission. Taken together, Short‐Stays made up more than 40% of the hospital‐based care delivered to children admitted from an ED. Stable trends in CMI over time suggest that observation status may be replacing inpatient status designated care for pediatric Short‐Stays in these hospitals. Our findings suggest the lines between outpatient observation and short‐stay inpatient care are becoming increasingly blurred. These trends have occurred in the setting of changing policies for hospital reimbursement, requirements for patients to meet criteria to qualify for inpatient admissions, and efforts to avoid stays deemed unnecessary or inappropriate by their brief duration.19 Therefore there is a growing need to understand the impact of children under observation on the structure, delivery, and financing of acute hospital care for children.

Our results also have implications for pediatric health services research that relies on hospital administrative databases that do not contain observation stays. Currently, observation stays are systematically excluded from many inpatient administrative datasets.11, 12 Analyses of datasets that do not account for observation stays likely result in underestimation of hospitalization rates and hospital resource utilization for children. This may be particularly important for high‐volume conditions, such as asthma and acute infections, for which children commonly require brief periods of hospital‐based care beyond an ED encounter. Data from pediatric observation status admissions should be consistently included in hospital administrative datasets to allow for more comprehensive analyses of hospital resource utilization among children.

Prior research has shown that the diagnoses commonly treated in pediatric observation units overlap with the diagnoses for which children experience 1‐Day Stays.1, 20 We found a similar pattern of conditions for which children were under Observation Status and 1‐Day Stays with comparable severity of illness between the groups in terms of SCS scores. Our findings imply a need to determine how and why hospitals differentiate Observation Status from 1‐Day‐Stay groups in order to improve the assignment of observation status. Assuming continued pressures from payers to provide more care in outpatient or observation settings, there is potential for expansion of dedicated observation services for children in the US. Without designated observation units or processes to group patients with lower severity conditions, there may be limited opportunities to realize more efficient hospital care simply through the application of the label of observation status.

For more than 30 years, observation services have been provided to children who require a period of monitoring to determine their response to therapy and the need for acute inpatient admission from the ED.21While we were not able to determine the location of care for observation status patients in this study, we know that few children's hospitals have dedicated observation units and, even when an observation unit is present, not all observation status patients are cared for in dedicated observation units.9 This, in essence, means that most children under observation status are cared for in virtual observation by inpatient teams using inpatient beds. If observation patients are treated in inpatient beds and consume the same resources as inpatients, then cost‐savings based on reimbursement contracts with payers may not reflect an actual reduction in services. Pediatric institutions will need to closely monitor the financial implications of observation status given the historical differences in payment for observation and inpatient care.

With more than 70% of children being discharged home following observation, our results are comparable to the published literature2, 5, 6, 22, 23 and guidelines for observation unit operations.24 Similar to prior studies,4, 15, 2530 our results also indicate that return visits and readmissions following observation are uncommon events. Our findings can serve as initial benchmarks for condition‐specific outcomes for pediatric observation care. Studies are needed both to identify the clinical characteristics predictive of successful discharge home from observation and to explore the hospital‐to‐hospital variability in outcomes for observation. Such studies are necessary to identify the most successful healthcare delivery models for pediatric observation stays.

LIMITATIONS

The primary limitation to our results is that data from a subset of freestanding children's hospitals may not reflect observation stays at other children's hospitals or the community hospitals that care for children across the US. Only 18 of 42 current PHIS member hospitals have provided both outpatient visit and inpatient stay data for each year of the study period and were considered eligible. In an effort to ensure the quality of observation stay data, we included the 16 hospitals that assigned observation charges to at least 90% of their observation status stays in the PHIS database. The exclusion of the 2 hospitals where <90% of observation status patients were assigned observation charges likely resulted in an underestimation of the utilization of observation status.

Second, there is potential for misclassification of patient type given institutional variations in the assignment of patient status. The PHIS database does not contain information about the factors that were considered in the assignment of observation status. At the time of admission from the ED, observation or inpatient status is assigned. While this decision is clearly reserved for the admitting physician, the process is not standardized across hospitals.9 Some institutions have Utilization Managers on site to help guide decision‐making, while others allow the assignment to be made by physicians without specific guidance. As a result, some patients may be assigned to observation status at admission and reassigned to inpatient status following Utilization Review, which may bias our results toward overestimation of the number of observation stays that converted to inpatient status.

The third limitation to our results relates to return visits. An accurate assessment of return visits is subject to the patient returning to the same hospital. If children do not return to the same hospital, our results would underestimate return visits and readmissions. In addition, we did not assess the reason for return visit as there was no way to verify if the return visit was truly related to the index visit without detailed chart review. Assuming children return to the same hospital for different reasons, our results would overestimate return visits associated with observation stays. We suspect that many 3‐day return visits result from the progression of acute illness or failure to respond to initial treatment, and 30‐day readmissions reflect recurrent hospital care needs related to chronic illnesses.

Lastly, severity classification is difficult when analyzing administrative datasets without physiologic patient data, and the SCS may not provide enough detail to reveal clinically important differences between patient groups.

CONCLUSIONS

Short‐stay hospitalizations following ED visits are common among children, and the majority of pediatric short‐stays are under observation status. Analyses of inpatient administrative databases that exclude observation stays likely result in an underestimation of hospital resource utilization for children. Efforts are needed to ensure that patients under observation status are accounted for in hospital administrative datasets used for pediatric health services research, and healthcare resource allocation, as it relates to hospital‐based care. While the clinical outcomes for observation patients appear favorable in terms of conversion to inpatient admissions and return visits, the financial implications of observation status care within children's hospitals are currently unknown.

In recent decades, hospital lengths of stay have decreased and there has been a shift toward outpatient management for many pediatric conditions. In 2003, one‐third of all children admitted to US hospitals experienced 1‐day inpatient stays, an increase from 19% in 1993.1 Some hospitals have developed dedicated observation units for the care of children, with select diagnoses, who are expected to respond to less than 24 hours of treatment.26 Expansion of observation services has been suggested as an approach to lessen emergency department (ED) crowding7 and alleviate high‐capacity conditions within hospital inpatient units.8

In contrast to care delivered in a dedicated observation unit, observation status is an administrative label applied to patients who do not meet inpatient criteria as defined by third parties such as InterQual. While the decision to admit a patient is ultimately at the discretion of the ordering physician, many hospitals use predetermined criteria to assign observation status to patients admitted to observation and inpatient units.9 Treatment provided under observation status is designated by hospitals and payers as outpatient care, even when delivered in an inpatient bed.10 As outpatient‐designated care, observation cases do not enter publicly available administrative datasets of hospital discharges that have traditionally been used to understand hospital resource utilization, including the National Hospital Discharge Survey and the Kid's Inpatient Database.11, 12

We hypothesize that there has been an increase in observation status care delivered to children in recent years, and that the majority of children under observation were discharged home without converting to inpatient status. To determine trends in pediatric observation status care, we conducted the first longitudinal, multicenter evaluation of observation status code utilization following ED treatment in a sample of US freestanding children's hospitals. In addition, we focused on the most recent year of data among top ranking diagnoses to assess the current state of observation status stay outcomes (including conversion to inpatient status and return visits).

METHODS

DATA ANALYSIS

For each of the 6 years of study, we calculated the following proportions to determine trends over time: 1) the number of Observation Status admissions from the ED as a proportion of the total number of ED visits resulting in Observation or Inpatient admission, and 2) the number of 1‐Day Stays admitted from the ED as a proportion of the total number of ED visits resulting in Observation or Inpatient admissions. Trends were analyzed using linear regression. Trends were also calculated for the total volume of admissions from the ED and the case‐mix index (CMI). CMI was assessed to evaluate for changes in the severity of illness for children admitted from the ED over the study period. Each hospital's CMI was calculated as an average of their Observation and Inpatient Status discharges' charge weights during the study period. Charge weights were calculated at the All Patient Refined Diagnosis Related Groups (APR‐DRG)/severity of illness level (3M Health Information Systems, St Paul, MN) and were normalized national average charges derived by Thomson‐Reuters from their Pediatric Projected National Database. Weights were then assigned to each discharge based on the discharge's APR‐DRG and severity level assignment.

To assess the current outcomes for observation, we analyzed stays with associated observation billing codes from the most recent year of available data (2009). Stays with Observation patient type were considered to have been discharged from observation, while those with an Inpatient Status patient type were considered to have converted to an inpatient admission during the observation period.

Using the 2009 data, we calculated descriptive statistics for patient characteristics (eg, age, gender, payer) comparing Observation Stays, 1‐Day Stays, and longer‐duration Inpatient admissions using chi‐square statistics. Age was categorized using the American Academy of Pediatrics groupings: <30 days, 30 days1 year, 12 years, 34 years, 512 years, 1317 years, >18 years. Designated payer was categorized into government, private, and other, including self‐pay and uninsured groups.

We used the Severity Classification Systems (SCS) developed for pediatric emergency care to estimate severity of illness for the visit.17 In this 5‐level system, each ICD‐9 diagnosis code is associated with a score related to the intensity of ED resources needed to care for a child with that diagnosis. In our analyses, each case was assigned the maximal SCS category based on the highest severity ICD‐9 code associated with the stay. Within the SCS, a score of 1 indicates minor illness (eg, diaper dermatitis) and 5 indicates major illness (eg, septic shock). The proportions of visits within categorical SCS scores were compared for Observation Stays, 1‐Day Stays, and longer‐duration Inpatient admissions using chi‐square statistics.

We determined the top 10 ranking diagnoses for which children were admitted from the ED in 2009 using the Diagnosis Grouping System (DGS).18 The DGS was designed specifically to categorize pediatric ED visits into clinically meaningful groups. The ICD‐9 code for the principal discharge diagnosis was used to assign records to 1 of the 77 DGS subgroups. Within each of the top ranking DGS subgroups, we determined the proportion of Observation Stays, 1‐Day Stays, and longer‐duration Inpatient admissions.

To provide clinically relevant outcomes of Observation Stays for common conditions, we selected stays with observation charges from within the top 10 ranking observation stay DGS subgroups in 2009. Outcomes for observation included: 1) immediate outcome of the observation stay (ie, discharge or conversion to inpatient status), 2) return visits to the ED in the 3 days following observation, and 3) readmissions to the hospital in the 3 and 30 days following observation. Bivariate comparisons of return visits and readmissions for Observation versus 1‐Day Stays within DGS subgroups were analyzed using chi‐square tests. Multivariate analyses of return visits and readmissions were conducted using Generalized Estimating Equations adjusting for severity of illness by SCS score and clustering by hospital. To account for local practice patterns, we also adjusted for a grouped treatment variable that included the site level proportion of children admitted to Observation Status, 1‐Day‐Stays, and longer Inpatient admissions. All statistical analyses were performed using SAS (version 9.2, SAS Institute, Inc, Cary, NC); P values <0.05 were considered statistically significant.

RESULTS

Trends in Short‐Stays

An increase in proportion of Observation Stays was mirrored by a decrease in proportion of 1‐Day Stays over the study period (Figure 1). In 2009, there were 1.4 times more Observation Stays than 1‐Day Stays (25,653 vs 18,425) compared with 14,242 and 20,747, respectively, in 2004. This shift toward more Observation Stays occurred as hospitals faced a 16% increase in the total number of admissions from the ED (91,318 to 108,217) and change in CMI from 1.48 to 1.51. Over the study period, roughly 40% of all admissions from the ED were Short‐Stays (Observation and 1‐Day Stays). Median LOS for Observation Status stays was 1 day (interquartile range [IQR]: 11).

Figure 1

DISCUSSION

In this first, multicenter longitudinal study of pediatric observation following an ED visit, we found that Observation Status code utilization has increased steadily over the past 6 years and, in 2007, the proportion of children admitted to observation status surpassed the proportion of children experiencing a 1‐day inpatient admission. Taken together, Short‐Stays made up more than 40% of the hospital‐based care delivered to children admitted from an ED. Stable trends in CMI over time suggest that observation status may be replacing inpatient status designated care for pediatric Short‐Stays in these hospitals. Our findings suggest the lines between outpatient observation and short‐stay inpatient care are becoming increasingly blurred. These trends have occurred in the setting of changing policies for hospital reimbursement, requirements for patients to meet criteria to qualify for inpatient admissions, and efforts to avoid stays deemed unnecessary or inappropriate by their brief duration.19 Therefore there is a growing need to understand the impact of children under observation on the structure, delivery, and financing of acute hospital care for children.

Our results also have implications for pediatric health services research that relies on hospital administrative databases that do not contain observation stays. Currently, observation stays are systematically excluded from many inpatient administrative datasets.11, 12 Analyses of datasets that do not account for observation stays likely result in underestimation of hospitalization rates and hospital resource utilization for children. This may be particularly important for high‐volume conditions, such as asthma and acute infections, for which children commonly require brief periods of hospital‐based care beyond an ED encounter. Data from pediatric observation status admissions should be consistently included in hospital administrative datasets to allow for more comprehensive analyses of hospital resource utilization among children.

Prior research has shown that the diagnoses commonly treated in pediatric observation units overlap with the diagnoses for which children experience 1‐Day Stays.1, 20 We found a similar pattern of conditions for which children were under Observation Status and 1‐Day Stays with comparable severity of illness between the groups in terms of SCS scores. Our findings imply a need to determine how and why hospitals differentiate Observation Status from 1‐Day‐Stay groups in order to improve the assignment of observation status. Assuming continued pressures from payers to provide more care in outpatient or observation settings, there is potential for expansion of dedicated observation services for children in the US. Without designated observation units or processes to group patients with lower severity conditions, there may be limited opportunities to realize more efficient hospital care simply through the application of the label of observation status.

For more than 30 years, observation services have been provided to children who require a period of monitoring to determine their response to therapy and the need for acute inpatient admission from the ED.21While we were not able to determine the location of care for observation status patients in this study, we know that few children's hospitals have dedicated observation units and, even when an observation unit is present, not all observation status patients are cared for in dedicated observation units.9 This, in essence, means that most children under observation status are cared for in virtual observation by inpatient teams using inpatient beds. If observation patients are treated in inpatient beds and consume the same resources as inpatients, then cost‐savings based on reimbursement contracts with payers may not reflect an actual reduction in services. Pediatric institutions will need to closely monitor the financial implications of observation status given the historical differences in payment for observation and inpatient care.

With more than 70% of children being discharged home following observation, our results are comparable to the published literature2, 5, 6, 22, 23 and guidelines for observation unit operations.24 Similar to prior studies,4, 15, 2530 our results also indicate that return visits and readmissions following observation are uncommon events. Our findings can serve as initial benchmarks for condition‐specific outcomes for pediatric observation care. Studies are needed both to identify the clinical characteristics predictive of successful discharge home from observation and to explore the hospital‐to‐hospital variability in outcomes for observation. Such studies are necessary to identify the most successful healthcare delivery models for pediatric observation stays.

LIMITATIONS

The primary limitation to our results is that data from a subset of freestanding children's hospitals may not reflect observation stays at other children's hospitals or the community hospitals that care for children across the US. Only 18 of 42 current PHIS member hospitals have provided both outpatient visit and inpatient stay data for each year of the study period and were considered eligible. In an effort to ensure the quality of observation stay data, we included the 16 hospitals that assigned observation charges to at least 90% of their observation status stays in the PHIS database. The exclusion of the 2 hospitals where <90% of observation status patients were assigned observation charges likely resulted in an underestimation of the utilization of observation status.

Second, there is potential for misclassification of patient type given institutional variations in the assignment of patient status. The PHIS database does not contain information about the factors that were considered in the assignment of observation status. At the time of admission from the ED, observation or inpatient status is assigned. While this decision is clearly reserved for the admitting physician, the process is not standardized across hospitals.9 Some institutions have Utilization Managers on site to help guide decision‐making, while others allow the assignment to be made by physicians without specific guidance. As a result, some patients may be assigned to observation status at admission and reassigned to inpatient status following Utilization Review, which may bias our results toward overestimation of the number of observation stays that converted to inpatient status.

The third limitation to our results relates to return visits. An accurate assessment of return visits is subject to the patient returning to the same hospital. If children do not return to the same hospital, our results would underestimate return visits and readmissions. In addition, we did not assess the reason for return visit as there was no way to verify if the return visit was truly related to the index visit without detailed chart review. Assuming children return to the same hospital for different reasons, our results would overestimate return visits associated with observation stays. We suspect that many 3‐day return visits result from the progression of acute illness or failure to respond to initial treatment, and 30‐day readmissions reflect recurrent hospital care needs related to chronic illnesses.

Lastly, severity classification is difficult when analyzing administrative datasets without physiologic patient data, and the SCS may not provide enough detail to reveal clinically important differences between patient groups.

CONCLUSIONS

Short‐stay hospitalizations following ED visits are common among children, and the majority of pediatric short‐stays are under observation status. Analyses of inpatient administrative databases that exclude observation stays likely result in an underestimation of hospital resource utilization for children. Efforts are needed to ensure that patients under observation status are accounted for in hospital administrative datasets used for pediatric health services research, and healthcare resource allocation, as it relates to hospital‐based care. While the clinical outcomes for observation patients appear favorable in terms of conversion to inpatient admissions and return visits, the financial implications of observation status care within children's hospitals are currently unknown.