By Judith Owens, MD, MPH, and Patrick Sorenson, MA, RPSGT

 

Image of child being examined.Standards for the use of portable monitoring (PM) to determine the presence and severity of obstructive sleep apnea (OSA) in the adult population, while still somewhat controversial, have now been employed in varying degrees in the United States and abroad. The use of PM is increasingly becoming accepted practice for the evaluation of uncomplicated adult sleep-disordered breathing (SDB).1,2

While still considered the “gold standard,” in-laboratory attended testing is being gradually replaced due to the changing environment of the health care system and limitations in patient access to care inherent with in-laboratory testing. Increasingly, third-party payors expect sleep laboratories to conduct PM in the adult patient population unless a justification for in-laboratory testing is made on a case-by-case basis.

With PM in adults becoming more commonplace, questions about pediatric PM need to be answered. Two key factors need to be weighed when considering PM in the pediatric population: patient access and the need for guidelines.3,4

Patient Access

Standardization

It is important to consider the type and quality of information yielded by in-lab versus in-home polysomnography, specifically as this relates to children. In adults, the minimal standard channels include airflow, respiratory effort, and blood oxygenation. If two channels are used to evaluate thoraco-abdominal efforts, this type of testing falls into the category of a Type 3 evaluation. However, these channels may be insufficient for the comprehensive evaluation of OSA in the pediatric population and a Type 2 test (unattended, ?7 channels) may be more appropriate for in-home testing in children. A Type 2 test would more accurately differentiate between obstructive and central events, especially important because the latter is observed with increased frequency in the pediatric population.

At minimum, in addition to the above, in-home pediatric testing also should include as standard:

1. Snore sensor to help differentiate the type of apneic event or expose those periods of increased respiratory resistance that can be quite subtle and occur with greater frequency in children as compared to adults.

2. ECG to reveal heart rate variability that is often present in children during OSA events as well as determine the presence of ectopic beats and arrhythmias.

3. Some measure of sleep state such as EEG and EOG leads to aid in the determination of state-dependent breathing, an important requirement specified in the 1996 American Thoracic Society published standards for cardiopulmonary studies in children.7

4. CO2 measurement (end tidal or transcutaneous) to assess hypoventilation and CO2 retention.

5. Audiovisual recording to aid the scoring and interpreting practitioner in the evaluation of parasomnias, primary snoring, positional and caregiver effects.

Any additional channels also should be incorporated into the scoring algorithms for inclusion in approved pediatric in-home testing.

 

Pediatric polysomnography is currently increasing in demand yet supply is limited. Several factors are having an impact on the balance. In 2011, the American Academy of Sleep Medicine (AASM) published a set of evidence-based Practice Parameters for Respiratory Indications for Polysomnography (PSG) in Children.5 The parameters recommended that all children undergoing adenotonsillectomy for sleep-disordered breathing have a diagnostic nocturnal in-lab sleep study both to establish the diagnosis of OSA and to determine severity.

These recommendations were based on the premise that history and physical exam, alone or in combination with other diagnostic methodologies such as nocturnal oximetry or audiotaping snoring, were neither sufficiently sensitive nor specific to differentiate between primary snoring (ie, without ventilatory abnormalities) and clinically significant sleep-disordered breathing in children. Epidemiological data suggest that only 10% of the approximately 500,000 children undergoing adenotonsillectomy annually in the United States currently have a PSG evaluation prior to the procedure.6 A significant contributor to this situation is the lack of pediatric-specific technical resources and laboratory space to meet the demand.

A second factor impacting the supply/demand balance are the AASM practice parameters, which recommend that follow-up PSG be conducted in those children with conditions in which residual sleep-disordered breathing is likely to be present following adenotonsillectomy (eg, obesity, severe baseline SDB, craniofacial anomalies).

Finally, the growing body of evidence linking pediatric OSA with adverse behavioral and cognitive consequences is being increasingly disseminated to health care providers, educators, and parents, further increasing the demand for diagnostic PSG in children.

These factors have created a mismatch between demand and supply suggesting that there is a real need to improve patient access to care in children with suspected sleep-disordered breathing and that PM, under highly controlled and specifically delineated circumstances and in limited pediatric patient populations, may be part of the solution. At issue is whether limited channel ambulatory studies in children are a viable alternative to full polysomnography and if they can be accurate, safe, and well-tolerated, as well as cost-effective, in the diagnosis of SDB in children. The evidence-based review that formed the basis for the 2011 AASM pediatric practice parameters for PSG addressed this issue briefly but concluded that adequate data did not yet exist to make formal recommendations.6

Guidelines and Methodologies

Pediatric PM is in need of clarification and standardization. For example, in 2011, Collop et al2 developed a system of classification of OSA devices for out-of-center (OOC) testing in adults, which reflects the evolution of the technology used today. This system classifies devices by what parameters are being monitored: ie, sleep, cardiovascular, oximetry, position, effort, and respiratory (yielding the acronym, SCOPER). While the authors discussed the capabilities and limitations of the various OOC devices according to the parameters measured, the objective of the review was not to make definitive statements regarding practice guidelines or management principles. Importantly, the applicability of these OOC systems to the pediatric population was specifically not addressed.

Besides a need for clarification about which devices are most suited for pediatric PM, there is a need for development of pediatric PM guidelines. Such guidelines are necessary for the evaluation of pediatric patients with sleep complaints by sleep practitioners prior to employing PM for the study of OSA. The AASM guidelines for the use of PM in adults state that if the recommendations for a comprehensive sleep evaluation by a qualified practitioner are followed, PM may be used as an alternative to PSG for the diagnosis of OSA in patients with a high pretest probability of moderate to severe OSA. Similar probability ratings for children do not exist; thus, triaging of pediatric patients for PM is far less straightforward.

Furthermore, the AASM does not support the use of PM in patient groups with significant comorbid medical conditions that may negatively impact the diagnostic accuracy of PM. These include, but are not limited to, moderate to severe pulmonary disease, neuromuscular disease, and congestive heart failure. Many children requiring evaluation for OSA, particularly in tertiary care centers, have significant comorbid medical conditions. Future pediatric guidelines about the use of PM will need to specifically define inclusion and exclusion criteria in regard to medical conditions, including congenital syndromes, which may preclude the use of PM. Equally important, similar criteria should be developed for children with psychiatric and neurodevelopmental comorbidities.

Portable Monitoring Perks

Despite the need for pediatric PM guidelines to be further clarified, there may be identifiable advantages in particular pediatric populations and under certain circumstances that make PM a viable and desirable alternative to in-lab PSG.3 For example, children (and caregivers) may be more comfortable in familiar surroundings, which may in turn, reduce the so-called “first night effect.” This may be particularly true for children with anxiety disorders and those for whom new environments may be challenging (eg, children with autism). Many families, especially single-parent families, face logistical challenges with child care for siblings if one parent is required to spend the night in the sleep lab. Conducting a sleep study in the child’s habitual environment also may give a more accurate portrayal of their respiratory status, particularly if environmental allergies are likely to play an important role in the genesis of their sleep-disordered breathing. Finally, the accessibility of PM may be advantageous in assessing response to treatment for OSA, including adenotonsillectomy or medically supervised weight loss, in a more time-sensitive manner, particularly given the relative paucity of sleep labs with expertise in the pediatric population.

Are We There Yet?

A number of studies have now documented both the feasibility and accuracy of PM in children,7-12 including children with comorbid medical13,14 and psychiatric conditions.15 In the Cleveland Children’s Sleep and Health study,12 for example, technically acceptable studies were produced in 94% of the studies; however, this study employed a research assistant to place the sensors and a courier to pick up the equipment the following day. These studies also have helped to identify potential challenges in implementation of PM specific to the pediatric population, including sensor (particularly airflow) loss, the ability of the child to cooperate to maintain sensor integrity, determination of the optimal target patient group, and the need for caregiver education and involvement to maintain sensor integrity. Moreover, the accuracy and reliability of alternative ambulatory metrics in children have not yet been determined. Finally, while the relative cost of home versus in-lab PSG is substantially less, if repeat in-lab studies are frequently needed due to inadequate or flawed data, the ultimate cost savings may be substantially reduced.

While there are likely to be benefits associated with home studies in the pediatric population, including

LinkedIn-Logo-bigIs portable monitoring appropriate for a pediatric population? How should the technology be applied in this patient population? Join the discussion

improvements in access to care and reduced burden for families, there are still many unanswered questions that need to be addressed before PM becomes an accepted diagnostic modality for children and adolescents. The challenge for pediatric sleep medicine professionals is to develop comprehensive guidelines for the safe and effective use of PM in children (including appropriate populations, specific parameters to be included, required expertise of labs, and scoring and interpretation), with the focus being on quality of care first and foremost, and secondarily on cost savings. We must recognize the unique needs of children and families and educate our adult medicine colleagues about standards of care specific to this population. Once there is an evidence base established for the validity and reliability of in-home PM for children, we can move forward in setting standards for the use of home monitoring in the pediatric population, with the goal of improving the lives of children and those who care for them. SR

Image of Judith Owens and Patrick Sorenson. Judith Owens, MD, MPH, is director of Sleep Medicine at Children’s National Medical Center, Washington, DC.

Patrick Sorenson, MA, RPSGT, is sleep laboratory manager at Children’s National Medical Center. Questions for the authors can be submitted to [email protected]

 

References

1. Collop NA, Anderson WM, Boehlecke B, et al. Clinical guidelines for the use of unattended portable monitors in the diagnosis of obstructive sleep apnea in adult patients. Portable Monitoring Task Force of the American Academy of Sleep Medicine. J Clin Sleep Med. 2007;3(7):737-747.

2. Collop NA, Tracy SL, Kapur V, et al. Obstructive sleep apnea devices for out-of-center (OOC) testing: technology evaluation. J Clin Sleep Med. 2011;7(5):531-548.

3. Rosen CL. Use of portable monitoring for the diagnosis and management of sleep disordered breathing in children: highly desirable, but not ready for prime time. Sleep Med Clin. 2011;6(3):349-353.

4. Owens J, Kothare S, Sheldon S. PRO: “Not just little adults”: AASM should require pediatric accreditation for integrated sleep medicine programs serving both children (0-16 years) and adults. J Clin Sleep Med. 2012;8(5):473-476.

5. Aurora R, Zak R, Karippot A, et al. Practice Parameters for the Respiratory Indications for Polysomnography in Children. Sleep. 2011;34(3):379-88.

6. Wise MS, Nichols CD, Grigg-Damberger MM, et al. Executive summary of respiratory indications for polysomnography in children: an evidence-based review. Sleep. 2011;34(3);389-398AW.

7. Goodwin JL, Enright PL, Kaeming KL, et al. Feasibility of using unattended polysomnography in children for research—report of the Tucson Children’s Assessment of Sleep Apnea study (TuCASA). Sleep. 2001;24(8):937-944.

8. Goodwin JL, Silva GE, Kaemingk KL, Sherrill DL, Morgan WJ, Quan SF. Comparison between reported and recorded total sleep time and sleep latency in 6- to 11-year-old children: the Tucson Children’s Assessment of Sleep Apnea Study (TuCASA). Sleep Breath. 2007;11(2):85-92.

9. Kirk VG, Bohn SG, Flemons WW, Remmers JE. Comparison of home oximetry monitoring with laboratory polysomnography in children. Chest. 2003;124(5):1702-1708.

10. Poels PJ, Schilder AG, van den Berg S, Hoes AW, Joosten KF. Evaluation of a new device for home cardiorespiratory recording in children. Arch Otolaryngol Head Neck Surg. 2003;129(12):1281-1284.

11. Zucconi M, Calori G, Castronovo V, Ferini-Strambi L. Respiratory monitoring by means of an unattended device in children with suspected uncomplicated obstructive sleep apnea: a validation study. Chest. 2003;124(2):602-607.

12. Rosen CL, Larkin EK, Kirchner HL, et al. Prevalence and risk factors for sleep-disordered breathing in 8- to 11-year-old children: association with race and prematurity. J Pediatr. 2003;142(4):383-389.

13. Landon C. Novel methods of ambulatory physiologic monitoring in patients with neuromuscular disease. Pediatrics. 2009;123(suppl 4):S250-S252.

14. Bannink N, Mathijssen IM, Joosten KF. Use of ambulatory polysomnography in children with syndromic craniosynostosis. J Craniofac Surg. 2010;21(5):1365-1368.

15. Gruber R, Xi T, Frenette S, Robert M, Vannasinh P, Carrier J. Sleep disturbances in prepubertal children with attention deficit hyperactivity disorder: a home polysomnography study. Sleep. 2009;32(3):343-350.