Nonteaching Hospitals May Be Best for Colon Resections

Mortality and length of stay following colon resection are significantly reduced at nonteaching hospitals compared with teaching hospitals, according to a retrospective analysis of 6 years' worth of data in the National Inpatient Sample.

Following risk and volume adjustment, teaching hospitals were associated with a 14% increased risk of operative mortality, Dr. Awori J. Hayanga reported at the annual Academic Surgical Congress in Fort Myers, Fla. In addition, there was a significant increase in length of stay—10.4 days at teaching hospitals vs. 8.5 days at nonteaching hospitals—and a trend toward an increase in total charges from about $6,000 to more than $8,000.

“The assumption is that teaching hospitals have higher volumes for all procedures, and that's not the case. … Most colon resections in the United States are not performed in teaching hospitals,” Dr. Hayanga said in an interview. “Cancer makes up the minority of resections that are performed on the colon. More resections are performed for benign disease.” The bulk of resections for benign colon disease are performed at nonteaching hospitals.

“We are postulating that there might be a tipping point in the volume-outcome ratio that shifts in favor of nonteaching hospitals—once you hit the critical volume of procedures,” said Dr. Hayanga, a surgical resident at the University of Michigan in Ann Arbor.

The analysis conducted by Dr. Hayanga and his colleagues was supplemented with data from the Area Resource File and the National Inpatient Sample. Logistic regression analysis was used to estimate 30-day mortality while linear regression analysis was used to estimate both length of stay and total charges. A teaching hospital met the definition by the American Hospital Association and was affiliated with either an Accreditation Council for Graduate Medical Education-accredited general surgery residency and/or colon fellowship at the institution.

The analysis included patients over the age of 18 who had undergone a colon resection as classified by ICD-9 codes.

Covariates included age, sex, race, insurance status, geographic region, institutional volume and urban/suburban/rural status, median county income, and percentage of county residents living below the federal poverty level.

“Teaching hospitals—with their propensity for performing rare and specialized surgery—tend to see sicker patients, who require the resources that are available only at these tertiary centers to get these patients better,” Dr. Hayanga said. “There is a feeling that there is a qualitatively different patient who comes to teaching hospitals.”

To attempt to control for possible differences in the types of patients seen at teaching vs. nonteaching hospitals, the investigators included the Charlson comorbidity index as a covariate.

In all, 115,250 patients underwent colon resection during the time period at more than 2,000 hospitals. Most patients (60%) received care at nonteaching hospitals. Overall, the mortality rate was 3.8%.

The researchers concluded that teaching hospitals may offer improved outcomes for complex oncologic surgical resections but may have worse outcomes for less complex surgery. Most of the less complex procedures are performed at nonteaching hospitals.

The databases have some limitations, and the study raises more questions than it answers, Dr. Hayanga acknowledged, adding that to accurately determine this relationship, a randomized prospective study would be needed for further clarification.

Mortality and length of stay following colon resection are significantly reduced at nonteaching hospitals compared with teaching hospitals, according to a retrospective analysis of 6 years' worth of data in the National Inpatient Sample.

Following risk and volume adjustment, teaching hospitals were associated with a 14% increased risk of operative mortality, Dr. Awori J. Hayanga reported at the annual Academic Surgical Congress in Fort Myers, Fla. In addition, there was a significant increase in length of stay—10.4 days at teaching hospitals vs. 8.5 days at nonteaching hospitals—and a trend toward an increase in total charges from about $6,000 to more than $8,000.

“The assumption is that teaching hospitals have higher volumes for all procedures, and that's not the case. … Most colon resections in the United States are not performed in teaching hospitals,” Dr. Hayanga said in an interview. “Cancer makes up the minority of resections that are performed on the colon. More resections are performed for benign disease.” The bulk of resections for benign colon disease are performed at nonteaching hospitals.

“We are postulating that there might be a tipping point in the volume-outcome ratio that shifts in favor of nonteaching hospitals—once you hit the critical volume of procedures,” said Dr. Hayanga, a surgical resident at the University of Michigan in Ann Arbor.

The analysis conducted by Dr. Hayanga and his colleagues was supplemented with data from the Area Resource File and the National Inpatient Sample. Logistic regression analysis was used to estimate 30-day mortality while linear regression analysis was used to estimate both length of stay and total charges. A teaching hospital met the definition by the American Hospital Association and was affiliated with either an Accreditation Council for Graduate Medical Education-accredited general surgery residency and/or colon fellowship at the institution.

The analysis included patients over the age of 18 who had undergone a colon resection as classified by ICD-9 codes.

Covariates included age, sex, race, insurance status, geographic region, institutional volume and urban/suburban/rural status, median county income, and percentage of county residents living below the federal poverty level.

“Teaching hospitals—with their propensity for performing rare and specialized surgery—tend to see sicker patients, who require the resources that are available only at these tertiary centers to get these patients better,” Dr. Hayanga said. “There is a feeling that there is a qualitatively different patient who comes to teaching hospitals.”

To attempt to control for possible differences in the types of patients seen at teaching vs. nonteaching hospitals, the investigators included the Charlson comorbidity index as a covariate.

In all, 115,250 patients underwent colon resection during the time period at more than 2,000 hospitals. Most patients (60%) received care at nonteaching hospitals. Overall, the mortality rate was 3.8%.

The researchers concluded that teaching hospitals may offer improved outcomes for complex oncologic surgical resections but may have worse outcomes for less complex surgery. Most of the less complex procedures are performed at nonteaching hospitals.

The databases have some limitations, and the study raises more questions than it answers, Dr. Hayanga acknowledged, adding that to accurately determine this relationship, a randomized prospective study would be needed for further clarification.

Mortality and length of stay following colon resection are significantly reduced at nonteaching hospitals compared with teaching hospitals, according to a retrospective analysis of 6 years' worth of data in the National Inpatient Sample.

Following risk and volume adjustment, teaching hospitals were associated with a 14% increased risk of operative mortality, Dr. Awori J. Hayanga reported at the annual Academic Surgical Congress in Fort Myers, Fla. In addition, there was a significant increase in length of stay—10.4 days at teaching hospitals vs. 8.5 days at nonteaching hospitals—and a trend toward an increase in total charges from about $6,000 to more than $8,000.

“The assumption is that teaching hospitals have higher volumes for all procedures, and that's not the case. … Most colon resections in the United States are not performed in teaching hospitals,” Dr. Hayanga said in an interview. “Cancer makes up the minority of resections that are performed on the colon. More resections are performed for benign disease.” The bulk of resections for benign colon disease are performed at nonteaching hospitals.

“We are postulating that there might be a tipping point in the volume-outcome ratio that shifts in favor of nonteaching hospitals—once you hit the critical volume of procedures,” said Dr. Hayanga, a surgical resident at the University of Michigan in Ann Arbor.

The analysis conducted by Dr. Hayanga and his colleagues was supplemented with data from the Area Resource File and the National Inpatient Sample. Logistic regression analysis was used to estimate 30-day mortality while linear regression analysis was used to estimate both length of stay and total charges. A teaching hospital met the definition by the American Hospital Association and was affiliated with either an Accreditation Council for Graduate Medical Education-accredited general surgery residency and/or colon fellowship at the institution.

The analysis included patients over the age of 18 who had undergone a colon resection as classified by ICD-9 codes.

Covariates included age, sex, race, insurance status, geographic region, institutional volume and urban/suburban/rural status, median county income, and percentage of county residents living below the federal poverty level.

“Teaching hospitals—with their propensity for performing rare and specialized surgery—tend to see sicker patients, who require the resources that are available only at these tertiary centers to get these patients better,” Dr. Hayanga said. “There is a feeling that there is a qualitatively different patient who comes to teaching hospitals.”

To attempt to control for possible differences in the types of patients seen at teaching vs. nonteaching hospitals, the investigators included the Charlson comorbidity index as a covariate.

In all, 115,250 patients underwent colon resection during the time period at more than 2,000 hospitals. Most patients (60%) received care at nonteaching hospitals. Overall, the mortality rate was 3.8%.

The researchers concluded that teaching hospitals may offer improved outcomes for complex oncologic surgical resections but may have worse outcomes for less complex surgery. Most of the less complex procedures are performed at nonteaching hospitals.

The databases have some limitations, and the study raises more questions than it answers, Dr. Hayanga acknowledged, adding that to accurately determine this relationship, a randomized prospective study would be needed for further clarification.