Sleep Strategies: Choosing the right CPAP equipment

Continuous positive airway pressure (CPAP) has long been considered the gold standard treatment for OSA. Recently, a variety of new treatment approaches have become available for mild and moderate OSA, including nasal resistance valves, nerve stimulators, and negative pressure devices. Nonetheless, CPAP remains unmatched in efficacy, as well as the frequency and severity of side effects associated with treatment. The main drawback of CPAP is the required use of a mask interface and pressurized air during sleep, which is uncomfortable for some patients.

This article will highlight recent work investigating issues associated with equipment choice for practitioners treating OSA patients with CPAP and discuss how proper equipment choices and educational programs can reduce common complaints associated with CPAP use.

Mask choice

Finding a suitable mask interface is one of the most critical aspects of achieving adequate treatment compliance. The four general styles to choose from are oronasal (full-mask), standard nasal (over the nose), nasal pillows (in the nose), and the rarely-used oral.

Most clinicians choose an initial mask after CPAP titration based on a combination of patient feedback and air leakage rates but may change the mask style after home implementation in order to improve patient tolerance. Unfortunately, many clinicians are unaware that CPAP levels may need to be adjusted after changing masks. Two studies have shown that oronasal masks require significantly more pressure to ensure adequate OSA treatment during CPAP titration compared with standard nasal and nasal pillows masks (Ebben et al. Sleep Med. 2012;13[6]:645; Borel et al. PLoS ONE. 2013;8[5]:e64382).

In a separate study in which nasal masks were replaced with oronasal masks, the apnea-hypopnea index (AHI) increased to greater than 10 events per hour in half of patients who had been previously titrated to less than five per hour with the nasal mask (Ebben et al. Sleep Med. 2014;15[6]:619). Caution should be used when making a mask change to ensure that adequate disease control is maintained.

Humidification

In the past few years, humidification has been routinely added to most CPAP machines in order to improve comfort. The benefit appears to come from a reduction in dryness related to regular CPAP use (Ruhle et al. Sleep Breath. 2011;15[3]:479). Some patients report that humidification is particularly helpful in the winter months, when indoor humidity is low. Heated humidification has been found to produce significantly more humidity and causes less insensible water loss from the respiratory tract compared with unheated units (Randerath et al. Eur J Respir. 2002;20[1]:183). Unfortunately, the humidifier significantly increases the size and weight of the treatment machine, though it can be removed for travel if desired. In addition, the humidifier requires additional maintenance; if not cleaned regularly, there is a risk of bacterial colonization of the humidification chamber (Chin et al. J Clin Sleep Med. 2013; 9[8]:747).

In some instances, patients may complain of excess water condensation in the hose, particularly in the presence of a cool sleeping environment. Some CPAP manufacturers now offer heated hoses, which can significantly reduce this condensation. A second option is to add an insulating hose cover to help maintain a higher internal temperature. Generally, these covers are a good choice if the cost of a heated hose is not covered by a patient’s insurance.

Pressure relief

A common complaint often heard from patients using CPAP is that the pressure feels too high, particularly when exhaling. In response, some equipment makers have developed pressure relief systems that allow an adjustable pressure drop during exhalation with standard CPAP units. These systems work by transiently reducing pressure during exhalation by a set amount, according to their proprietary algorithm (Dolan et al. Sleep and Breath. 2009;13:73). However, not all patients find this pressure relief effective at making CPAP easier to use. When tested empirically, pressure relief has not been consistently shown to improve CPAP compliance (Dolan et al. Sleep Breath. 2009;13[1]:73).

Compliance data monitoring

Many patients benefit from discussing and reviewing treatment efficacy at their follow-up visits. Most modern CPAP equipment allows for such data monitoring, that may include duration and specific times of machine use, leak rate, snoring periods, and residual respiratory events, subdivided into hypopneas and apneas. In some cases, the software can distinguish between central ("clear airway") and obstructive events using forced oscillation techniques to measure upper airway resistance. This information allows the clinician to adjust settings and ensure that treatment is optimized and used as prescribed.

Clinicians should familiarize themselves with the different reporting systems that provide these data, and train their office staff on using software to capture information for all CPAP users. Notably, the algorithms used to capture residual respiratory events are not completely accurate; identification of such events is based only on measures of flow.

While it is probably acceptable to take extreme values at face value, whether low or very high, the imprecision of the methodology makes it more difficult to reliably use middling values in a clinical setting. (Schwab et al. Am J Respir Crit Care Med. 2013;188[5]:613). If a patient remains symptomatic despite no evidence of residual respiratory events from the adherence data download, a retitration study should still be considered.

Educational programs

Adherence to CPAP has been shown to increase when providers engage patients in educational programs to enhance compliance and understanding of the potential health-care consequences of untreated OSA (Lai et al. Chest. 2014 May 8. doi: 10.1378/ chest.13-2228. [Epub ahead of print]).

Early education and continuous support provide reinforcement of the need for adherence to therapy, as well as an opportunity to personalize the treatment and adjust settings and equipment as needed for each individual patient. Although specific guidelines for the best timing of the educational intervention are still lacking, evidence suggests that long-term compliance with CPAP might be determined as early as 2 weeks after therapy is initiated (Aloia et al. J Clin Sleep Med. 2005;1[4]:346). Therefore, educational programs should be readily available for prospective and new CPAP users in order to enhance their understanding of OSA and knowledge about CPAP treatment and to provide them with a venue for reviewing and managing compliance-related issues. Such programs can be run by dedicated sleep technologists, respiratory therapists, or nurses in clinics where physician availability is more limited.

Summary

CPAP remains the most effective treatment for OSA, though adherence is a struggle for many patients. Identifying the best mask for a given patient, determining whether humidification or an expiratory pressure drop should be added and making early and frequent contact after prescription can all assist in improving long-term CPAP use. Regular review of adherence data with the patient is also important, modifying the therapy as necessary to optimize comfort, understanding that such changes may necessitate a subsequent pressure adjustment to maintain disease control.

Implementing a comprehensive approach to managing patients using CPAP therapy can impact compliance by reducing treatment-related complaints and improving comfort.

Dr. Ebben is Assistant Professor of Psychology in Clinical Neurology, Department of Neurology; and Dr. Krieger is Associate Clinical Professor, Departments of Medicine, Neurology, and Genetic Medicine; Weill Cornell Medical College of Cornell University, New York, New York.

Continuous positive airway pressure (CPAP) has long been considered the gold standard treatment for OSA. Recently, a variety of new treatment approaches have become available for mild and moderate OSA, including nasal resistance valves, nerve stimulators, and negative pressure devices. Nonetheless, CPAP remains unmatched in efficacy, as well as the frequency and severity of side effects associated with treatment. The main drawback of CPAP is the required use of a mask interface and pressurized air during sleep, which is uncomfortable for some patients.

This article will highlight recent work investigating issues associated with equipment choice for practitioners treating OSA patients with CPAP and discuss how proper equipment choices and educational programs can reduce common complaints associated with CPAP use.

Mask choice

Finding a suitable mask interface is one of the most critical aspects of achieving adequate treatment compliance. The four general styles to choose from are oronasal (full-mask), standard nasal (over the nose), nasal pillows (in the nose), and the rarely-used oral.

Most clinicians choose an initial mask after CPAP titration based on a combination of patient feedback and air leakage rates but may change the mask style after home implementation in order to improve patient tolerance. Unfortunately, many clinicians are unaware that CPAP levels may need to be adjusted after changing masks. Two studies have shown that oronasal masks require significantly more pressure to ensure adequate OSA treatment during CPAP titration compared with standard nasal and nasal pillows masks (Ebben et al. Sleep Med. 2012;13[6]:645; Borel et al. PLoS ONE. 2013;8[5]:e64382).

In a separate study in which nasal masks were replaced with oronasal masks, the apnea-hypopnea index (AHI) increased to greater than 10 events per hour in half of patients who had been previously titrated to less than five per hour with the nasal mask (Ebben et al. Sleep Med. 2014;15[6]:619). Caution should be used when making a mask change to ensure that adequate disease control is maintained.

Humidification

In the past few years, humidification has been routinely added to most CPAP machines in order to improve comfort. The benefit appears to come from a reduction in dryness related to regular CPAP use (Ruhle et al. Sleep Breath. 2011;15[3]:479). Some patients report that humidification is particularly helpful in the winter months, when indoor humidity is low. Heated humidification has been found to produce significantly more humidity and causes less insensible water loss from the respiratory tract compared with unheated units (Randerath et al. Eur J Respir. 2002;20[1]:183). Unfortunately, the humidifier significantly increases the size and weight of the treatment machine, though it can be removed for travel if desired. In addition, the humidifier requires additional maintenance; if not cleaned regularly, there is a risk of bacterial colonization of the humidification chamber (Chin et al. J Clin Sleep Med. 2013; 9[8]:747).

In some instances, patients may complain of excess water condensation in the hose, particularly in the presence of a cool sleeping environment. Some CPAP manufacturers now offer heated hoses, which can significantly reduce this condensation. A second option is to add an insulating hose cover to help maintain a higher internal temperature. Generally, these covers are a good choice if the cost of a heated hose is not covered by a patient’s insurance.

Pressure relief

A common complaint often heard from patients using CPAP is that the pressure feels too high, particularly when exhaling. In response, some equipment makers have developed pressure relief systems that allow an adjustable pressure drop during exhalation with standard CPAP units. These systems work by transiently reducing pressure during exhalation by a set amount, according to their proprietary algorithm (Dolan et al. Sleep and Breath. 2009;13:73). However, not all patients find this pressure relief effective at making CPAP easier to use. When tested empirically, pressure relief has not been consistently shown to improve CPAP compliance (Dolan et al. Sleep Breath. 2009;13[1]:73).

Compliance data monitoring

Many patients benefit from discussing and reviewing treatment efficacy at their follow-up visits. Most modern CPAP equipment allows for such data monitoring, that may include duration and specific times of machine use, leak rate, snoring periods, and residual respiratory events, subdivided into hypopneas and apneas. In some cases, the software can distinguish between central ("clear airway") and obstructive events using forced oscillation techniques to measure upper airway resistance. This information allows the clinician to adjust settings and ensure that treatment is optimized and used as prescribed.

Clinicians should familiarize themselves with the different reporting systems that provide these data, and train their office staff on using software to capture information for all CPAP users. Notably, the algorithms used to capture residual respiratory events are not completely accurate; identification of such events is based only on measures of flow.

While it is probably acceptable to take extreme values at face value, whether low or very high, the imprecision of the methodology makes it more difficult to reliably use middling values in a clinical setting. (Schwab et al. Am J Respir Crit Care Med. 2013;188[5]:613). If a patient remains symptomatic despite no evidence of residual respiratory events from the adherence data download, a retitration study should still be considered.

Educational programs

Adherence to CPAP has been shown to increase when providers engage patients in educational programs to enhance compliance and understanding of the potential health-care consequences of untreated OSA (Lai et al. Chest. 2014 May 8. doi: 10.1378/ chest.13-2228. [Epub ahead of print]).

Early education and continuous support provide reinforcement of the need for adherence to therapy, as well as an opportunity to personalize the treatment and adjust settings and equipment as needed for each individual patient. Although specific guidelines for the best timing of the educational intervention are still lacking, evidence suggests that long-term compliance with CPAP might be determined as early as 2 weeks after therapy is initiated (Aloia et al. J Clin Sleep Med. 2005;1[4]:346). Therefore, educational programs should be readily available for prospective and new CPAP users in order to enhance their understanding of OSA and knowledge about CPAP treatment and to provide them with a venue for reviewing and managing compliance-related issues. Such programs can be run by dedicated sleep technologists, respiratory therapists, or nurses in clinics where physician availability is more limited.

Summary

CPAP remains the most effective treatment for OSA, though adherence is a struggle for many patients. Identifying the best mask for a given patient, determining whether humidification or an expiratory pressure drop should be added and making early and frequent contact after prescription can all assist in improving long-term CPAP use. Regular review of adherence data with the patient is also important, modifying the therapy as necessary to optimize comfort, understanding that such changes may necessitate a subsequent pressure adjustment to maintain disease control.

Implementing a comprehensive approach to managing patients using CPAP therapy can impact compliance by reducing treatment-related complaints and improving comfort.

Dr. Ebben is Assistant Professor of Psychology in Clinical Neurology, Department of Neurology; and Dr. Krieger is Associate Clinical Professor, Departments of Medicine, Neurology, and Genetic Medicine; Weill Cornell Medical College of Cornell University, New York, New York.

Continuous positive airway pressure (CPAP) has long been considered the gold standard treatment for OSA. Recently, a variety of new treatment approaches have become available for mild and moderate OSA, including nasal resistance valves, nerve stimulators, and negative pressure devices. Nonetheless, CPAP remains unmatched in efficacy, as well as the frequency and severity of side effects associated with treatment. The main drawback of CPAP is the required use of a mask interface and pressurized air during sleep, which is uncomfortable for some patients.

This article will highlight recent work investigating issues associated with equipment choice for practitioners treating OSA patients with CPAP and discuss how proper equipment choices and educational programs can reduce common complaints associated with CPAP use.

Mask choice

Finding a suitable mask interface is one of the most critical aspects of achieving adequate treatment compliance. The four general styles to choose from are oronasal (full-mask), standard nasal (over the nose), nasal pillows (in the nose), and the rarely-used oral.

Most clinicians choose an initial mask after CPAP titration based on a combination of patient feedback and air leakage rates but may change the mask style after home implementation in order to improve patient tolerance. Unfortunately, many clinicians are unaware that CPAP levels may need to be adjusted after changing masks. Two studies have shown that oronasal masks require significantly more pressure to ensure adequate OSA treatment during CPAP titration compared with standard nasal and nasal pillows masks (Ebben et al. Sleep Med. 2012;13[6]:645; Borel et al. PLoS ONE. 2013;8[5]:e64382).

In a separate study in which nasal masks were replaced with oronasal masks, the apnea-hypopnea index (AHI) increased to greater than 10 events per hour in half of patients who had been previously titrated to less than five per hour with the nasal mask (Ebben et al. Sleep Med. 2014;15[6]:619). Caution should be used when making a mask change to ensure that adequate disease control is maintained.

Humidification

In the past few years, humidification has been routinely added to most CPAP machines in order to improve comfort. The benefit appears to come from a reduction in dryness related to regular CPAP use (Ruhle et al. Sleep Breath. 2011;15[3]:479). Some patients report that humidification is particularly helpful in the winter months, when indoor humidity is low. Heated humidification has been found to produce significantly more humidity and causes less insensible water loss from the respiratory tract compared with unheated units (Randerath et al. Eur J Respir. 2002;20[1]:183). Unfortunately, the humidifier significantly increases the size and weight of the treatment machine, though it can be removed for travel if desired. In addition, the humidifier requires additional maintenance; if not cleaned regularly, there is a risk of bacterial colonization of the humidification chamber (Chin et al. J Clin Sleep Med. 2013; 9[8]:747).

In some instances, patients may complain of excess water condensation in the hose, particularly in the presence of a cool sleeping environment. Some CPAP manufacturers now offer heated hoses, which can significantly reduce this condensation. A second option is to add an insulating hose cover to help maintain a higher internal temperature. Generally, these covers are a good choice if the cost of a heated hose is not covered by a patient’s insurance.

Pressure relief

A common complaint often heard from patients using CPAP is that the pressure feels too high, particularly when exhaling. In response, some equipment makers have developed pressure relief systems that allow an adjustable pressure drop during exhalation with standard CPAP units. These systems work by transiently reducing pressure during exhalation by a set amount, according to their proprietary algorithm (Dolan et al. Sleep and Breath. 2009;13:73). However, not all patients find this pressure relief effective at making CPAP easier to use. When tested empirically, pressure relief has not been consistently shown to improve CPAP compliance (Dolan et al. Sleep Breath. 2009;13[1]:73).

Compliance data monitoring

Many patients benefit from discussing and reviewing treatment efficacy at their follow-up visits. Most modern CPAP equipment allows for such data monitoring, that may include duration and specific times of machine use, leak rate, snoring periods, and residual respiratory events, subdivided into hypopneas and apneas. In some cases, the software can distinguish between central ("clear airway") and obstructive events using forced oscillation techniques to measure upper airway resistance. This information allows the clinician to adjust settings and ensure that treatment is optimized and used as prescribed.

Clinicians should familiarize themselves with the different reporting systems that provide these data, and train their office staff on using software to capture information for all CPAP users. Notably, the algorithms used to capture residual respiratory events are not completely accurate; identification of such events is based only on measures of flow.

While it is probably acceptable to take extreme values at face value, whether low or very high, the imprecision of the methodology makes it more difficult to reliably use middling values in a clinical setting. (Schwab et al. Am J Respir Crit Care Med. 2013;188[5]:613). If a patient remains symptomatic despite no evidence of residual respiratory events from the adherence data download, a retitration study should still be considered.

Educational programs

Adherence to CPAP has been shown to increase when providers engage patients in educational programs to enhance compliance and understanding of the potential health-care consequences of untreated OSA (Lai et al. Chest. 2014 May 8. doi: 10.1378/ chest.13-2228. [Epub ahead of print]).

Early education and continuous support provide reinforcement of the need for adherence to therapy, as well as an opportunity to personalize the treatment and adjust settings and equipment as needed for each individual patient. Although specific guidelines for the best timing of the educational intervention are still lacking, evidence suggests that long-term compliance with CPAP might be determined as early as 2 weeks after therapy is initiated (Aloia et al. J Clin Sleep Med. 2005;1[4]:346). Therefore, educational programs should be readily available for prospective and new CPAP users in order to enhance their understanding of OSA and knowledge about CPAP treatment and to provide them with a venue for reviewing and managing compliance-related issues. Such programs can be run by dedicated sleep technologists, respiratory therapists, or nurses in clinics where physician availability is more limited.

Summary

CPAP remains the most effective treatment for OSA, though adherence is a struggle for many patients. Identifying the best mask for a given patient, determining whether humidification or an expiratory pressure drop should be added and making early and frequent contact after prescription can all assist in improving long-term CPAP use. Regular review of adherence data with the patient is also important, modifying the therapy as necessary to optimize comfort, understanding that such changes may necessitate a subsequent pressure adjustment to maintain disease control.

Implementing a comprehensive approach to managing patients using CPAP therapy can impact compliance by reducing treatment-related complaints and improving comfort.

Dr. Ebben is Assistant Professor of Psychology in Clinical Neurology, Department of Neurology; and Dr. Krieger is Associate Clinical Professor, Departments of Medicine, Neurology, and Genetic Medicine; Weill Cornell Medical College of Cornell University, New York, New York.