Medline ® Abstracts for References 88,89
of 'Evaluation of suspected obstructive sleep apnea in children'
Comparison of nap and overnight polysomnography in children.
Marcus CL, Keens TG, Ward SL
Pediatr Pulmonol. 1992;13(1):16.
Overnight polysomnography is the "gold standard" for diagnosing sleep-disordered breathing. However, the limited number of resources for pediatric polysomnography make the availability of a screening test for sleep-disordered breathing highly desirable. Therefore, we compared 1 hour daytime nap polysomnography to overnight polysomnography in 40 children [mean age, 5.4 +/- 0.8 (SE) years]with sleep-disordered breathing; 76% of children were sedated with chloral hydrate for nap polysomnography; none was sedated for overnight polysomnography. Studies were done 26 +/- 4 days apart. Chest wall motion, ECG, end-tidal PCO2 (PETCO2), arterial oxygen saturation (SaO2), and electrooculogram were monitored. Nap studies had a sensitivity of 74%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 17% in predicting sleep-disordered breathing. Significantly more children had obstructive apnea and desaturation (SaO2 less than 90%) during overnight polysomnography. The peak PETCO2 and the SaO2 nadir were significantly worse during overnight polysomnography. However, the percentage of time during which abnormalities were manifested did not differ between nap and overnight polysomnography. Despite the use of sedation, nap polysomnography underestimated sleep-disordered breathing. We conclude that sleep-disordered breathing detected by nap polysomnography is always confirmed by overnight polysomnography and speculate that nap polysomnography may be an effective screening method for sleep-disordered breathing. However, overnight polysomnography should be performed if nap polysomnography is inconclusive. Chloral hydrate may be used effectively to facilitate sleep for nap polysomnography in children.
Division of Neonatology and Pediatric Pulmonology, Childrens Hospital Los Angeles, University of Southern California School of Medicine 90027.
Should children with suspected obstructive sleep apnea syndrome and normal nap sleep studies have overnight sleep studies?
Saeed MM, Keens TG, Stabile MW, Bolokowicz J, Davidson Ward SL
STUDY OBJECTIVES: Overnight polysomnography (ONP) is the "gold standard" for the diagnosis of sleep-disordered breathing, but it is expensive and time-consuming. Thus, daytime nap studies have been used as screening tests. If the findings of a nap study are normal or mildly abnormal, should ONP be performed? Do specific abnormalities in nap studies predict abnormal findings in ONP? To answer these questions, we conducted this study.
DESIGN: Retrospective chart review.
SETTING: Children's hospital.
PARTICIPANTS: One hundred forty-three children with suspected obstructive sleep apnea syndrome secondary to isolated adenotonsillar hypertrophy, who had normal or mildly abnormal nap studies, and underwent ONP.
MEASUREMENTS AND RESULTS: We compared daytime nap and overnight polysomnograms in 143 children (52 girls;mean [+/- SD]age, 5.6 +/- 3.1 years). Total sleep time was 1 h in daytime nap, and 5.1 +/- 1.3 h in ONP. The interval between the two studies was 5.9 +/- 4.8 months. The findings of 59% of the nap studies were mildly abnormal, while 66% of overnight studies were abnormal. No individual nap study parameter (including short obstructive apneas, hypopneas, hypoxemia, hypoventilation, snoring, paradoxical breathing, gasping, retractions) had good sensitivity at predicting abnormal overnight polysomnograms, but most had good specificity and positive predictive value.
CONCLUSIONS: We conclude that individual nap study parameters are not very sensitive in predicting abnormal ONP findings. However, when nap study parameters are abnormal, the chance of obstructive sleep apnea syndrome is high.
Division of Pediatric Pulmonology, Mattel Children's Hospital, University of California at Los Angeles School of Medicine, USA.