Adult criteria for obstructive sleep apnea do not identify children with serious obstruction

Assessment of obstructive sleep apnoea in children: What are the challenges we face?

There is an increasing demand for the assessment of sleep-disordered breathing in children of all ages to prevent the deleterious neurocognitive and behaviour consequences of the under-diagnosis and under-treatment of obstructive sleep apnoea [OSA]. OSA can be considered in three broad categories based on predominating contributory features: OSA type 1 [enlarged tonsils and adenoids], type II [Obesity] and type III [craniofacial abnormalities, syndromal, storage diseases and neuromuscular conditions]. The reality is that sleep questionnaires or calculations of body mass index in isolation are poorly predictive of OSA in individuals. Globally, the access to testing in tertiary referral centres is comprehensively overwhelmed by the demand and financial cost. This has prompted the need for better awareness and focussed history taking, matched with simpler tools with acceptable accuracy used in the setting of likely OSA. Consequently, we present key indications for polysomnography and present scalable, existing alternatives for assessment of OSA in the hospital or home setting, using polygraphy, oximetry or contactless sleep monitoring.

A deep learning model based on the combination of convolutional and recurrent neural networks to enhance pulse oximetry ability to classify sleep stages in children with sleep apnea

Characterization of sleep stages is essential in the diagnosis of sleep-related disorders but relies on manual scoring of overnight polysomnography (PSG) recordings, which is onerous and labor-intensive. Accordingly, we aimed to develop an accurate deep-learning model for sleep staging in children suffering from pediatric obstructive sleep apnea (OSA) using pulse oximetry signals. For this purpose, pulse rate (PR) and blood oxygen saturation (SpO2) from 429 childhood OSA patients were analyzed. A CNN-RNN architecture fed with PR and SpO2 signals was developed to automatically classify wake (W), non-Rapid Eye Movement (NREM), and REM sleep stages. This architecture was composed of: (i) a convolutional neural network (CNN), which learns stage-related features from raw PR and SpO2 data; and (ii) a recurrent neural network (RNN), which models the temporal distribution of the sleep stages. The proposed CNN-RNN model showed a high performance for the automated detection of W/NREM/REM sleep stages (86.0% accuracy and 0.743 Cohen's kappa). Furthermore, the total sleep time estimated for each children using the CNN-RNN model showed high agreement with the manually derived from PSG (intra-class correlation coefficient = 0.747). These results were superior to previous works using CNN-based deep-learning models for automatic sleep staging in pediatric OSA patients from pulse oximetry signals. Therefore, the combination of CNN and RNN allows to obtain additional information from raw PR and SpO2 data related to sleep stages, thus being useful to automatically score sleep stages in pulse oximetry tests for children evaluated for suspected OSA.Clinical Relevance-This research establishes the usefulness of a CNN-RNN architecture to automatically score sleep stages in pulse oximetry tests for pediatric OSA diagnosis.

Automated Evaluation of Upper Airway Obstruction Based on Deep Learning

Objectives

This study is aimed at developing a screening tool that could evaluate the upper airway obstruction on lateral cephalograms based on deep learning.

Methods

We developed a novel and practical convolutional neural network model to automatically evaluate upper airway obstruction based on ResNet backbone using the lateral cephalogram. A total of 1219 X-ray images were collected for model training and testing.

Results

In comparison with VGG16, our model showed a better performance with sensitivity of 0.86, specificity of 0.89, PPV of 0.90, NPV of 0.85, and F1-score of 0.88, respectively. The heat maps of cephalograms showed a deeper understanding of features learned by deep learning model.

Conclusion

This study demonstrated that deep learning could learn effective features from cephalograms and automated evaluate upper airway obstruction according to X-ray images. Clinical Relevance. A novel and practical deep convolutional neural network model has been established to relieve dentists' workload of screening and improve accuracy in upper airway obstruction.

Measurement of snoring and stertor using the Sonomat to assess effectiveness of upper airway surgery in children

STUDY OBJECTIVES

The success of surgical treatment for pediatric sleep-disordered breathing is typically assessed using the mixed and obstructive apnea-hypopnea index (MOAHI). Although an important metric, previous work has shown that snoring and stertor are also associated with sleep disruption. Our aim was to assess the efficacy of surgery using the Sonomat (Sonomedical Pty Ltd), a noncontact sleep assessment system, that accurately records complete and partial upper airway obstruction.

METHODS

Forty children (< 18 years) had a Sonomat study, in their own beds, before and after surgery. As an MOAHI ≥ 1 event/h is considered abnormal, the same threshold was applied to snore/stertor runs. Median (interquartile range) values are reported.

RESULTS

Respiratory event-induced movements decreased from 12.0 (8.7-19.0) to 0.5 (0.1-3.2) events/h (P < .01), with no significant change in spontaneous movements: 12.8 (9.8-17.9) to 16.5 (13.7-26.1) events/h (P = .07). The MOAHI decreased from 4.5 (1.9-8.6) to 0.0 (0.0-0.4) events/h (P < .01). Snoring and/or stertor runs decreased from 32.8 (23.4-44.4) to 3.0 (0.2-14.6) events/h (P < .01). Thirty-four children had an MOAHI < 1 event/h following surgery; however, 20 had snore and/or stertor runs ≥ 1 event/h and 11 had snore and/or stertor runs ≥ 5 events/h. Only 14 (35%) children had a postsurgery MOAHI < 1 event/h combined with snoring and/or stertor < 1 runs/h.

CONCLUSIONS

Although surgery is effective in improving breathing, success rates are overestimated using the MOAHI. Our results indicate that snoring and/or stertor are still present at levels that may disrupt sleep despite a normalization of the MOAHI and that when obstructed breathing was objectively measured, there was a large variation in its response to surgery.

CITATION

Norman MB, Harrison HC, Sullivan CE, Milross MA. Measurement of snoring and stertor using the Sonomat to assess effectiveness of upper airway surgery in children. J Clin Sleep Med. 2022;18(6):1649-1656.

Airflow Analysis in the Context of Sleep Apnea

The airflow (AF) is a physiological signal involved in the overnight polysomnography (PSG) that reflects the respiratory activity. This signal is able to show the particularities of sleep apnea and is therefore used to define apneic events. In this regard, a growing number of studies have shown the usefulness of employing the overnight airflow as the only or combined information source for diagnosing sleep apnea in both children and adults. Due to its easy acquisition and interpretation, this biosignal has been widely analyzed by means of different signal processing techniques. In this chapter, we review the main methodological approaches applied to characterize and extract relevant information from this signal. In view of the results, we can conclude that the overnight airflow successfully reflects the particularities caused by the occurrence of apneic and hypopneic events and provides useful information for obtaining relevant biomarkers that characterize this disease.

Dental, oral pH, orthodontic and salivary values in children with obstructive sleep apnea

OBJECTIVES

Mouth breathing is a key feature of obstructive sleep apnea (OSA). The current study evaluated dental, salivary and orthodontic characteristics of children with OSA, and compared them to those of children without OSA.

MATERIALS AND METHODS

Twenty-two children (mean age 5.3 years, 13 males) with OSA and 21 children without OSA who served as a control group (mean age 6.8 years, 11 males) underwent dental examinations. The OSA group was classified according to the apnea-hypopnea Index. Clinical examination included plaque index, gingival index, caries status, pH at 7 oral sites, salivary carries bacterial counts and inflammatory cytokine levels. Orthodontics measurements were calculated as the percentage of children with values in the normal range, in each group.

RESULTS

The mean values of the decayed, missing and filled teeth (DMFT)/dmft index, the gingival index and the plaque index were higher in the OSA than the control group. Salivary Mutans streptococci and lactobacilli counts were significantly higher in the OSA than the control group; as were pH values in the hard and soft palate, and in the posterior and middle tongue. Significantly lower values were observed in the OSA than the control group for most of the orthodontic variables examined. Similarly, stratification of AHI according to severity shows the lowest values among those with mild OSA, and the highest among those with severe AHI.

CONCLUSIONS

Compared to a control group, mouth breathing children with obstructive sleep apnea had differences in oral microbiota, greater acidity and poorer dental status.

CLINICAL RELEVANCE

Clinicians should be aware of the various oral disturbances that may accompany OSA, and implement preventive measures.

Assessment of Airflow and Oximetry Signals to Detect Pediatric Sleep Apnea-Hypopnea Syndrome Using AdaBoost

The reference standard to diagnose pediatric Obstructive Sleep Apnea (OSA) syndrome is an overnight polysomnographic evaluation. When polysomnography is either unavailable or has limited availability, OSA screening may comprise the automatic analysis of a minimum number of signals. The primary objective of this study was to evaluate the complementarity of airflow (AF) and oximetry (SpO₂) signals to automatically detect pediatric OSA. Additionally, a secondary goal was to assess the utility of a multiclass AdaBoost classifier to predict OSA severity in children. We extracted the same features from AF and SpO₂ signals from 974 pediatric subjects. We also obtained the 3% Oxygen Desaturation Index (ODI) as a common clinically used variable. Then, feature selection was conducted using the Fast Correlation-Based Filter method and AdaBoost classifiers were evaluated. Models combining ODI 3% and AF features outperformed the diagnostic performance of each signal alone, reaching 0.39 Cohens's kappa in the four-class classification task. OSA vs. No OSA accuracies reached 81.28%, 82.05% and 90.26% in the apnea-hypopnea index cutoffs 1, 5 and 10 events/h, respectively. The most relevant information from SpO₂ was redundant with ODI 3%, and AF was complementary to them. Thus, the joint analysis of AF and SpO₂ enhanced the diagnostic performance of each signal alone using AdaBoost, thereby enabling a potential screening alternative for OSA in children.

Evaluation of the relationship between malocclusions and sleep-disordered breathing in children

OBJECTIVE

To determine the relationship between dental/skeletal malocclusions and sleep-disordered breathing (SDB) in the early diagnosis and treatment of sleep disorders in children.

METHODS

Patients were evaluated by pedodontists to identify dental, skeletal, and functional malocclusion (n = 240; <15 years). In order to determine the sleep and daytime behavior of the patients, pediatric sleep questionnaires (PSQ) were applied. Per results of the PSQ, patients with a mean of ≥ 0.33 were defined as the high-risk group.

RESULTS

A total of 25.8% children were in the high-risk group, with the most convex profile, high-angle growth direction, and mandibular retrognathy. The prevalence of habitual snoring, mouth breathing, and dry mouth was 48.4%, 64.5%, and 87.2% among all high-risk children, respectively.

CONCLUSION

Convex profile, high-angle growth direction, and retrognathic mandible were determined as risk factors for SDB. The prevalence of dry mouth, mouth breathing, and snoring was higher in the high-risk group.

Treatment of Obstructive Sleep Apnea in Children: Handling the Unknown with Precision

Treatment approaches to pediatric obstructive sleep apnea (OSA) have remarkably evolved over the last two decades. From an a priori assumption that surgical removal of enlarged upper airway lymphadenoid tissues (T&A) was curative in the vast majority of patients as the recommended first-line treatment for pediatric OSA, residual respiratory abnormalities are frequent. Children likely to manifest persistent OSA after T&A include those with severe OSA, obese or older children, those with concurrent asthma or allergic rhinitis, children with predisposing oropharyngeal or maxillomandibular factors, and patients with underlying medical conditions. Furthermore, selection anti-inflammatory therapy or orthodontic interventions may be preferable in milder cases. The treatment options for residual OSA after T&A encompass a large spectrum of approaches, which may be complementary, and clearly require multidisciplinary cooperation. Among these, continuous positive airway pressure (CPAP), combined anti-inflammatory agents, rapid maxillary expansion, and myofunctional therapy are all part of the armamentarium, albeit with currently low-grade evidence supporting their efficacy. In this context, there is urgent need for prospective evidence that will readily identify the correct candidate for a specific intervention, and thus enable some degree of scientifically based precision in the current one approach fits all model of pediatric OSA medical care.

Snoring and stertor are associated with more sleep disturbance than apneas and hypopneas in pediatric SDB

PURPOSE

Polysomnography is not recommended for children at home and does not adequately capture partial upper airway obstruction (snoring and stertor), the dominant pathology in pediatric sleep-disordered breathing. New methods are required for assessment. Aims were to assess sleep disruption linked to partial upper airway obstruction and to evaluate unattended Sonomat use in a large group of children at home.

METHODS

Children with suspected obstructive sleep apnea (OSA) had a single home-based Sonomat recording (n = 231). Quantification of breath sound recordings allowed identification of snoring, stertor, and apneas/hypopneas. Movement signals were used to measure quiescent (sleep) time and sleep disruption.

RESULTS

Successful recordings occurred in 213 (92%) and 113 (53%) had no OSA whereas only 11 (5%) had no partial obstruction. Snore/stertor occurred more frequently (15.3 [5.4, 30.1] events/h) and for a longer total duration (69.9 min [15.7, 140.9]) than obstructive/mixed apneas and hypopneas (0.8 [0.0, 4.7] events/h, 1.2 min [0.0, 8.5]); both p < 0.0001. Many non-OSA children had more partial obstruction than those with OSA. Most intervals between snore and stertor runs were < 60 s (79% and 61% respectively), indicating that they occur in clusters. Of 14,145 respiratory-induced movement arousals, 70% were preceded by runs of snore/stertor with the remainder associated with apneas/hypopneas.

CONCLUSIONS

Runs of snoring and stertor occur much more frequently than obstructive apneas/hypopneas and are associated with a greater degree of sleep disruption. Children with and without OSA are frequently indistinguishable regarding the amount, frequency, and the degree of sleep disturbance caused by snoring and stertor.

Sleep-disordered breathing and reaction time in children

Background

The incidence of obstructive sleep apnea (OSA) and sleep-disordered breathing (SDB) in children exceeds the availability of polysomnography (PSG) to definitively diagnose OSA and identify children at higher risk of perioperative complications. As sleep deficits are associated with slower reaction times (RTs), measuring RT may be a cost-effective approach to objectively identify SDB symptoms.

Aim

The aim of this study is to compare RT on a standard 10-minute psychomotor vigilance test (PVT) based on children’s history of OSA/SDB.

Methods

Children, 6–11 years of age, were enrolled from two different clinical groups. The SDB group included children undergoing adenotonsillectomy with a clinical history of SDB, OSA, or snoring. The control group included children with no history of SDB, OSA, or snoring who were scheduled for surgery other than adenotonsillectomy. RT was measured via 10-minute PVT (Ambulatory Monitoring Inc., Ardsley, NY, USA). Median RT was calculated for each patient based on all responses to stimuli during the PVT assessment and was compared to published age-sex-specific norms. The proportion of children exceeding RT norms was compared between study groups.

Results

The study included 72 patients (36/36 male/female, median age 7 years), 46 with SDB and 26 without SDB. There was no difference in the RT between the two groups. Fifty-four percent of patients with SDB exceeded norms for median RT vs 42% of control patients (95% CI of difference: – 12, 36; P=0.326).

Conclusion

Approximately half of the patients in both groups exceeded published norms for median RT on PVT. Despite its convenience, measurement of RT did not distinguish between patients with probable SDB/OSA for preoperative risk stratification.

Comparison of Obstructive Sleep Apnea Syndrome in Children with Cleft Palate following Furlow Palatoplasty or Pharyngeal Flap for Velopharyngeal Insufficiency

Objective

To evaluate the incidence and severity of obstructive sleep apnea syndrome (OSAS) in patients with cleft palate having a Furlow palatoplasty or pharyngeal flap for correction of velopharyngeal insufficiency (VPI).

Patients

A total of 48 nonsyndromic children with repaired cleft palate with VPI were enrolled in the study. Twenty of the children had a Furlow palatoplasty (F group) and 28 children had a pharyngeal flap (P group) for correction of VPI.

Interventions

An overnight polysomnography evaluation was done to evaluate the incidence and severity of OSAS 6 months or more postoperatively.

Main Outcome Measures

Symptoms of OSAS, respiratory disturbance index (RDI), oxyhemoglobin desaturation index (DI), and sleep stages were measured.

Results

In the P group, the mean percentage of stage 2 sleep was lower than the F group (p < .05). The mean RDI and DI were larger in the P group, compared with the F group (p < .001). The incidence and severity of OSAS were higher in the P group, compared with the F group (p < .001 and p = 0.05, respectively).

Conclusions

A Furlow palatoplasty should be used in deference to a pharyngeal flap whenever possible on the basis of the preoperative evaluation of VPI because of the decreased incidence and severity of OSAS.

High-Flow, Heated, Humidified Air Via Nasal Cannula Treats CPAP-Intolerant Children With Obstructive Sleep Apnea

STUDY OBJECTIVES

Continuous positive airway pressure (CPAP) is effective but challenging for children with obstructive sleep apnea (OSA). High-flow air via open nasal cannula (HFNC) as treatment in children remains controversial. We report the efficacy of HFNC in children with OSA and CPAP intolerance, a titration protocol, and a discussion of potential mechanisms.

METHODS

Patients aged 1 to 18 years with OSA (defined by obstructive apnea-hypopnea index [OAHI] greater than 1 event/h) and CPAP intolerance were enrolled. Routine polysomnography data obtained during 1 night wearing HFNC was compared with diagnostic data by Wilcoxon rank-sum test.

RESULTS

Ten school-age subjects (representing all patients attempting HFNC at our institution to date) with varied medical conditions, moderate to severe OSA, and CPAP intolerance wore HFNC from 10 to 50 L/min of room air with oxygen supplementation if needed (room air alone for 6 of the 10). HFNC reduced median OAHI from 11.1 events/h (interquartile range 8.7-18.8 events/h) to 2.1 events/h (1.7-2.2 events/h; P = .002); increased oxyhemoglobin saturation (SpO₂) mean from 91.3% (89.6% to 93.5%) to 94.9% (92.4% to 96.0%; P < .002); increased SpO₂ nadir from 76.0% (67.3% to 82.3%) to 79.5% (77.2% to 86.0%; P = .032); decreased SpO₂ desaturation index from 19.2 events/h (12.7-25.8 events/h) to 6.4 events/h (4.7-10.7 events/h; P = .013); and reduced heart rate from 88 bpm (86-91 bpm) to 74 bpm (67-81 bpm; P = .004). Stratified analysis of the 6 subjects with only room air via HFNC, the OAHI, obstructive hypopnea index, and mean SpO₂ still demonstrated improvements (P = .031).

CONCLUSIONS

High-flow nasal cannula reduces respiratory events, improves oxygenation, reduces heart rate, and may be effective for CPAP intolerant children with moderate to severe OSA. Our data suggest HFNC warrants further study and consideration by payers as OSA therapy.

Tracheostomy for Severe Pediatric Obstructive Sleep Apnea: Indications and Outcomes

Objectives (1) To describe characteristics of pediatric patients undergoing tracheostomy for obstructive sleep apnea (OSA). (2) To highlight perioperative events and outcomes of the procedure. Study Design Case series with chart review. Setting Four tertiary care academic children's hospitals. Subjects and Methods Twenty-nine children aged <18 years from January 1, 2010, to December 31, 2015, who underwent tracheostomy for severe OSA, defined as an apnea-hypopnea index (AHI) >10, were included in the study. Data on patient characteristics, polysomnographic findings, comorbidities, and perioperative events and outcomes were collected and analyzed. Results Twenty-nine patients were included. Mean age at tracheostomy was 2.0 years (95% CI, -2.2 to 6.2). Mean body mass index z score was -1.2 (95% CI, -4.9 to -2.5). Mean preoperative AHI was 60.2 (95% CI, -15.7 to 136.1). Mean postoperative intensive care unit stay was 23.2 days (95% CI, 1.44-45.0). One procedure was complicated by bronchospasm. Thirteen patients had craniofacial abnormalities; 10 had a neurologic disorder resulting in hypotonia; and 5 had a diagnosis of laryngomalacia. Mean follow-up was 30.6 months (95% CI, -10.4 to 71.6). Six patients were decannulated, with a mean time to decannulation of 40.8 months (95% CI, 7.9-73.7). Five patients underwent capped sleep study prior to decannulation with a mean AHI of 6.6 (95% CI, -9.9 to 23.1) and a mean oxygen nadir of 90.0% (95% CI, 80%-100%). Conclusion OSA is an uncommon indication for tracheostomy in children. Patients who require the procedure usually have an associated syndromic diagnosis resulting in upper airway obstruction. The majority of children who undergo tracheostomy for OSA will remain dependent at 24 months.

Upper Airway Vibration Perception in School-Aged Children with Obstructive Sleep Apnea

STUDY OBJECTIVES

Children with the obstructive sleep apnea (OSA) have impaired upper airway two-point discrimination compared to controls. In addition, blunted vibration threshold detection (VT) in the palate has been recognized in adults with OSA, but has not been studied in children. Both findings are indicative of a defect in the afferent limb of the upper airway dilator reflex that could prevent upper airway dilation secondary to airway loading, resulting in airway collapse. We hypothesized that children with OSA have impaired palate VT compared to controls, and that this improves after OSA treatment.

METHODS

Case-control study. Children with OSA and healthy non-snoring controls underwent polysomnography and palate VT measurements. Children with OSA were retested after adenotonsillectomy.

RESULTS

29 children with OSA (median [interquartile range] age = 9.5 [7.5-12.6] years, obstructive apnea-hypopnea index [OAHI] = 11.3 [5.7-19.5] events/h, BMI z = 1.8 [1.3-2.1]) and 32 controls (age = 11.2 [9.3-13.5] years, P = 0.1; OAHI = 0.5 [0.1-0.7] events/h, P < 0.001; BMI z = 1 [0.3-1.7], P = 0.004) were tested. OSA palate VT (1.0 [0.8-1.5] vibration units) was similar to that of controls (1 [0.8-1.3], P = 0.37). 20 children with OSA were retested 4.4 (3.2-7.1) months after treatment. OAHI decreased from 13.1 (5.8-19) to 0.6 (0.2-2.5) events per hour (P < 0.001) postoperatively, but palate VT did not change (before = 1 [0.7-1.5], after = 1.2 [0.8-1.4], P = 0.37).

CONCLUSIONS

Children with OSA and controls have similar palate VT. Unlike in adults, palate VT does not seem to be affected by childhood OSA.

Duration criterion of respiratory events for children with obstructive sleep apnea

OBJECTIVE

To investigate the duration criterion of respiratory events in children with obstructive sleep apnea syndrome (OSAS) by analyzing standard nocturnal polysomnograms (PSG). To provide reference values for pediatric PSG.

METHODS

107 OSAS children diagnosed by PSG from January 2004 to May 2006 were randomly selected. The decrease in arterial oxygen saturation (ΔSaO2) and the corresponding event duration of each respiratory event were observed.

RESULTS

(1) There was significant positive correlation between oxygen desaturation values (ΔSaO2=0-17%) and the corresponding durations of respiratory events (P<0.001). (2) There was no significant difference in durations of respiratory events in rapid eye movement (REM) sleep and NREM sleep, the demographics between male and female children. (3) Significant positive correlation between age and duration of respiratory events (apnea/hypopnea) when oxygen desaturation values equal to 4% (ΔSaO2=4%) was observed. (4) The lower limit of 95% confidence intervals of which duration of oxygen desaturation value equals to 4% was 5.4s.

CONCLUSION

(1) PSG studies may allow the establishment of the duration criterion of significant respiratory events; (2) 5.4s can be defined as duration criteria of respiratory events; (3) the present study provides reference values for Pediatric PSG.

WITHDRAWN: Adenotonsillectomy for obstructive sleep apnoea in children

This review has been withdrawn because it has been split into the following reviews: '(Adeno)tonsillectomy versus non‐surgical management of obstructive sleep apnoea syndrome (OSAS) in children' (Schilder 2015) and 'Tonsillectomy versus tonsillotomy in children with sleep‐disordered breathing (including obstructive sleep apnoea)' (protocol) (Blackshaw 2014).

The editorial group responsible for this previously published document have withdrawn it from publication.

Respiratory cycle-related electroencephalographic changes during sleep in healthy children and in children with sleep disordered breathing

STUDY OBJECTIVE

To investigate respiratory cycle-related electroencephalographic changes (RCREC) in healthy children and in children with sleep disordered breathing (SDB) during scored event-free (SEF) breathing periods of sleep.

DESIGN

Interventional case-control repeated measurements design.

SETTING

Paediatric sleep laboratory in a hospital setting.

PARTICIPANTS

Forty children with SDB and 40 healthy, age- and sex-matched children.

INTERVENTIONS

Adenotonsillectomy in children with SDB and no intervention in controls.

MEASUREMENTS AND RESULTS

Overnight polysomnography; electroencephalography (EEG) power variations within SEF respiratory cycles in the overall and frequency band-specific EEG within stage 2 nonrapid eye movement (NREM) sleep, slow wave sleep (SWS), and rapid eye movement (REM) sleep. Within both groups there was a decrease in EEG power during inspiration compared to expiration across all sleep stages. Compared to controls, RCREC in children with SDB in the overall EEG were significantly higher during REM and frequency band specific RCRECs were higher in the theta band of stage 2 and REM sleep, alpha band of SWS and REM sleep, and sigma band of REM sleep. This between-group difference was not significant postadenotonsillectomy.

CONCLUSION

The presence of nonrandom respiratory cycle-related electroencephalographic changes (RCREC) in both healthy children and in children with sleep disordered breathing (SDB) during NREM and REM sleep has been demonstrated. The RCREC values were higher in children with SDB, predominantly in REM sleep and this difference reduced after adenotonsillectomy.

CITATION

Immanuel SA, Pamula Y, Kohler M, Martin J, Kennedy D, Saint DA, Baumert M. Respiratory cycle-related electroencephalographic changes during sleep in healthy children and in children with sleep disordered breathing.

Impact of sleep respiratory disorders on endothelial function in children

Obstructive sleep apnea syndrome (OSAS) in children can induce endothelial dysfunction, a well-known early marker of atherosclerosis. The study aimed to evaluate a link among endothelial function (measured by flow-mediated vasodilation (FMD)), obesity (evaluated by body mass index (BMI)), and sleep disordered breathing (SDB), assessed with apnoea/hypopnoea index (AHI), in a paediatric population. We demonstrated that our little OSAS patients showed an impaired endothelial function as compared to controls. In particular, the higher the AHI, the worst the FMD values and thus the endothelial function. Although the population sample is small, this study demonstrated that OSAS could impair endothelial function and worsen cardiovascular risk profile since childhood.

Respiratory and polysomnographic values in 3- to 5-year-old normal children at higher altitude

STUDY OBJECTIVES

To determine polysomnographic parameter differences in children living at higher altitude to children living near sea level.

DESIGN AND SETTING

Prospective study of non-snoring, normal children recruited from various communities around Denver, CO. In-lab, overnight polysomnograms were performed at a tertiary care children's hospital. All children required residence for greater than one year at an elevation around 1,600 meters.

PARTICIPANTS

45 children (62% female), aged 3-5 years, 88.9% non-Hispanic white with average BMI percentile for age of 47.8% ± 30.7%.

MEASUREMENTS AND RESULTS

Standard sleep indices were obtained and compared to previously published normative values in a similar population living near sea level (SLG). In the altitude group (AG), the apnea-hypopnea index was 1.8 ± 1.2 and the central apnea-hypopnea index was 1.7 ± 1.1, as compared to 0.9 ± 0.8 and 0.8 ± 0.7, respectively, (P ≤ 0.005) in SLG. Mean end-tidal CO2 level in AG was 42.3 ± 3.0 mm Hg and 40.6 ± 4.6 mm Hg in SLG (P = 0.049). The ≥ 4% desaturation index was 3.9 ± 2.0 in AG compared to 0.3 ± 0.4 in SLG (P < 0.001). Mean periodic limb movement in series index was 10.1 ± 12.3 in AG and 3.6 ± 5.4 in SLG (P = 0.001).

CONCLUSION

Comparison of altitude and sea level sleep studies in healthy children reveals significant differences in central apnea, apneahypopnea, desaturation, and periodic limb movement in series indices. Clinical providers should be aware of these differences when interpreting sleep studies and incorporate altitude-adjusted normative values in therapeutic-decision making algorithms.

Comparison of oxygen desaturation patterns in children and adults with sleep-disordered breathing

PURPOSE

Although the number of apnea-hypopnea episodes per hour apnea-hypopnea index (AHI) is typically used to evaluate sleep-disordered breathing (SDB) in adults, it does not provide an accurate characterization of SDB in children. We investigated differences in SDB patterns in children and adults to evaluate SDB severity in children.

MATERIALS AND METHODS

Fifteen adults (mean age, 45.3 ± 8.4 years) and 15 children (mean age, 6.7 ± 3.9 years) with adenotonsillar hypertrophy underwent standard polysomnography. The change of oxygen saturation (ΔSpO2) was defined as the difference between baseline SpO₂ during stable nighttime breathing and the lowest SpO₂ accompanied by an apnea-hypopnea event. The number of apnea-hypopnea episodes was determined using two different criteria to define an episode (criterion 1: cessation of airflow for at least 10s; criterion 2: cessation of airflow for at least two consecutive breaths).

RESULTS

Mean ΔSpO₂ accompanied by obstructive apneas lasting ≤10 s was significantly greater in children than in adults, although there was no significant difference in the duration of apnea-hypopnea episodes. The slope of the regression line between ΔSpO₂ and apnea-hypopnea duration in children was greater than in adults (P<0.005). AHI in children was higher when calculated using criterion 2 compared to criterion 1 (10.9 ± 9.4 vs. 6.5 ± 4.9/h, P=0.003).

CONCLUSIONS

ΔSpO₂ is a good indicator of SDB severity in children, and should therefore be considered in the diagnosis and treatment of pediatric SDB along with AHI.

Current definitions for neonatal apnoea: are they evidence based?

Apnoea is defined as cessation of breathing with implicit pathophysiology. This review considers definitions of neonatal apnoea currently available and explores the evidence to support their use. For preterm and term infants, apnoea definitions appear arbitrary, are not supported by guidelines and vary from study to study. Although most alarms on infant breathing monitors are set to alert after a respiratory pause >20s duration is detected, this time period is the equivalent of 17 missed breaths in a preterm infant. Apnoea is likely to be better defined by associated consequence than by pause duration alone in this age group; however, the degree of change in heart rate or oxygen saturation that defines a respiratory pause as pathological is yet to be defined. Further research is required to determine the characteristics that differentiate respiratory events of clinical consequence from normal respiratory variability in term and preterm infants.

Nasal CPAP therapy for infants with congenital stridor

Ten infants at ages from 1 to 5 months (1st and 2nd trimenon) suffering from congenital inspiratory stridor were examined, dependent on the respective severity of their stridorous phenomenons each, either clinically or/and endoscopically or/and polygraphically, for differentiation of the diagnoses and for assessment of their needs of nCPAP therapy.With the help of nCPAP it is possible to successfully treat even one-month-old babies who suffer from laryngomalacia. The therapy results in effective alleviation of the thorax recession, reduction of funnel chest development, stabilization of SaO2 around 95%, almost complete disappearing of the stridor through laryngeal functional stabilization and the normalization of the increased heart rate. Also to be emphasized is improvement of the sleep which is characterized by remarkably reduced motility. With nCPAP therapy the stridorous symptomatology is reduced within shorter time than even less severe phenomenons disappear in untreated children. By this therapeutic approach intubation, tracheotomy or laryngeal surgery can be avoided.

Airway considerations in craniofacial patients

Children with syndromic craniosynostosis have an increased risk of airway obstruction. Addressing this issue early in their clinical course helps ensure a safe result. Because of their abnormal airways and a higher risk of sleep-related breathing disorders, regular evaluation of the airway is recommended. An algorithm for evaluation, including sleep study, and management of such children is proposed. Patients with abnormal sleep studies should undergo endoscopy (nasendoscopy or flexible fiberoptic bronchoscopy) to determine the site of the obstruction and then adenotonsillectomy when appropriate. Continuous positive airway pressure, nasopharyngeal airways, or surgery, including osteotomy or even tracheostomy, may be necessary. Regular evaluation of the airway is critical, because the airway status may improve or worsen with growth of the child. Finally, ongoing communication with the craniofacial team allows planning of various procedures in the individual patient with optimal management of the airway.

The utility of a portable recording device for screening of obstructive sleep apnea in obese adolescents

STUDY OBJECTIVES

The ApneaLink Plus is a portable recording device that measures air flow, respiratory effort, heart rate, and pulse oximetry. In the current study, we asked whether this device could be used to screen for obstructive sleep apnea in the pediatric population.

METHODS

Sleep-laboratory polysomnography (PSG) was performed simultaneously with measurements using the portable device on obese pediatric patients referred for snoring. The obstructive apnea hypopnea index (OAHI) was calculated automatically by the device (autoscore) and manually by the investigators. Sensitivity, specificity, correlation, and receiver operating curves (ROC) were used to compare the portable device to PSG.

RESULTS

Twenty-five subjects (60% male, mean age 13.6 ± 3.0 years, OAHI on PSG 11.8 ± 27.1) were studied. We identified a significant correlation between the OAHI of the ApneaLink autoscore and PSG (Spearman Rho = 0.886 [p < 0.001]). Using the PSG results as standard, ROC curves comparing the ApneaLink OAHI with the PSG OAHI demonstrated high congruence. The autoscore agreement was very good at PSG OAHI > 1.5 (area under the receiver operating curve [AUC] 0.965, OAHI > 5 [AUC 0.937], and OAHI > 10 [AUC 1.00]). The agreement of the manual score and autoscore were essentially equivalent. The device's autoscore demonstrated high sensitivity at all cutoffs examined (100% at OAHI > 1.5, 85.7% at OAHI > 5, and 100% at OAHI > 10). The specificity increased with increasing cutoffs (46.2% at OAHI > 1.5, 83.3% at OAHI > 5, and 90.0% at OAHI > 10).

CONCLUSION

he ApneaLink Plus is a sensitive screening tool for evaluation of suspected OSAS in obese pediatric patients aged 9-18 years. The specificity improves with increasing OAHI cutoffs. The device detects OSAS when tested in a sleep laboratory on obese adolescents referred for symptoms of sleep related breathing disorder.

Paediatric traffic accident and obstructive sleep apnoea by antrochoanal polyps: case report and literature review

Antrochoanal polyps are hyperplasias of the nasal mucosa, which have their origin in the maxillary sinus and extend through the nasal cavity and the choanae into the naso- and oropharynx. In children antrochoanal polyps represent one of the more frequent manifestations of paediatric nasal polyposis. Most studies on antrochoanal polyps in children report only on nasal obstruction, hyponasal speech and snoring, which are also encountered in the most common cause of obstructive sleep apnoea syndrome; i.e. adenoid or tonsillar hyperplasia. Only very few studies report on additional health hazards by antrochoanal polyps ranging from obstructive sleep apnoea syndrome to swallowing disorders and cachexia. We present the case of an 8 year old girl with a bicycle accident caused by excessive daytime sleepiness and obstructive sleep apnoea syndrome due to an extensive antrochoanal polyp. After a transnasal polypectomy and meatotomy type II the obstructive sleep apnoea and day time sleepiness resolved completely. Awareness of this additional health hazard is important and correct evaluation and timely diagnosis of a potential antrochoanal polyp is mandatory because minimally invasive rhinosurgery is highly curative in preventing further impending problems.

Clinical practice guideline: tonsillectomy in children

OBJECTIVE

Tonsillectomy is one of the most common surgical procedures in the United States, with more than 530,000 procedures performed annually in children younger than 15 years. Tonsillectomy is defined as a surgical procedure performed with or without adenoidectomy that completely removes the tonsil including its capsule by dissecting the peritonsillar space between the tonsil capsule and the muscular wall. Depending on the context in which it is used, it may indicate tonsillectomy with adenoidectomy, especially in relation to sleep-disordered breathing. This guideline provides evidence-based recommendations on the preoperative, intraoperative, and postoperative care and management of children 1 to 18 years old under consideration for tonsillectomy. In addition, this guideline is intended for all clinicians in any setting who interact with children 1 to 18 years of age who may be candidates for tonsillectomy.

PURPOSE

The primary purpose of this guideline is to provide clinicians with evidence-based guidance in identifying children who are the best candidates for tonsillectomy. Secondary objectives are to optimize the perioperative management of children undergoing tonsillectomy, emphasize the need for evaluation and intervention in special populations, improve counseling and education of families of children who are considering tonsillectomy for their child, highlight the management options for patients with modifying factors, and reduce inappropriate or unnecessary variations in care.

RESULTS

The panel made a strong recommendation that clinicians should administer a single, intraoperative dose of intravenous dexamethasone to children undergoing tonsillectomy. The panel made a strong recommendation against clinicians routinely administering or prescribing perioperative antibiotics to children undergoing tonsillectomy. The panel made recommendations for (1) watchful waiting for recurrent throat infection if there have been fewer than 7 episodes in the past year or fewer than 5 episodes per year in the past 2 years or fewer than 3 episodes per year in the past 3 years; (2) assessing the child with recurrent throat infection who does not meet criteria in statement 2 for modifying factors that may nonetheless favor tonsillectomy, which may include but are not limited to multiple antibiotic allergy/intolerance, periodic fever, aphthous stomatitis, pharyngitis and adenitis, or history of peritonsillar abscess; (3) asking caregivers of children with sleep-disordered breathing and tonsil hypertrophy about comorbid conditions that might improve after tonsillectomy, including growth retardation, poor school performance, enuresis, and behavioral problems; (4) counseling caregivers about tonsillectomy as a means to improve health in children with abnormal polysomnography who also have tonsil hypertrophy and sleep-disordered breathing; (5) counseling caregivers that sleep-disordered breathing may persist or recur after tonsillectomy and may require further management; (6) advocating for pain management after tonsillectomy and educating caregivers about the importance of managing and reassessing pain; and (7) clinicians who perform tonsillectomy should determine their rate of primary and secondary posttonsillectomy hemorrhage at least annually. The panel offered options to recommend tonsillectomy for recurrent throat infection with a frequency of at least 7 episodes in the past year or at least 5 episodes per year for 2 years or at least 3 episodes per year for 3 years with documentation in the medical record for each episode of sore throat and 1 or more of the following: temperature >38.3°C, cervical adenopathy, tonsillar exudate, or positive test for group A β-hemolytic streptococcus.

Class II correction improves nocturnal breathing in adolescents

OBJECTIVE

To examine modifications in sleep pattern and in craniofacial morphology of adolescents with mandibular retrognathism.

MATERIALS AND METHODS

Sixteen subjects at maximum pubertal growth (12.6 years [±11.5 months]) were selected and treated for 12 months with maxillary expansion and mandibular advancement with a Herbst appliance. Cephalometric radiography and magnetic resonance imaging were obtained prior to and after treatment and were compared using the paired Student's t-test or the nonparametric Wilcoxon rank-sum test. Four polysomnographic recordings were obtained with pressurized nasal cannulae and were analyzed by analysis of variance.

RESULTS

The length of the mandible was increased, while the antero-posterior position of the maxilla remained stable. The posterior airway space was increased, the length of the tongue was preserved, and the hyoid bone was moved to a more anterior position. After Herbst treatment, sleep efficiency, sleep latency, rapid eye movement (REM) sleep latency, and percentage of REM sleep remained stable. We did observe a reduction (P < .05) in the relative proportions of stage 1 and stage 3-4 (from 4.30 ± 1.99 to 2.61 ± 1.83 for stage 1 and from 25.78 ± 7.00 to 19.17 ± 7.58 for stages 3-4) as well as an increase (P < .01) in the percentage of stage 2 after treatment (49.03 ± 6.25 to 56.90 ± 6.22). There was a reduction (P < .05) in the number of respiratory effort-related arousals (7.06 ± 5.37 to 1.31 ± 1.45 per hour of sleep) due to an increase (P < .01) in airway volume.

CONCLUSIONS

In the short term, the increase in airway space improved nocturnal breathing associated with the correction of mandibular retrognathism.

Pediatric obstructive sleep apnea assessment using pulse oximetry and dual RIP bands

The diagnosis of Obstructive Sleep Apnea (OSA) in children presents a challenging diagnostic problem given the high prevalence (2-3%), the resource intensity of the overnight polysomnography investigation, and the realisation that OSA poses a serious threat to the healthy growth and development of children. Previous attempts to develop OSA diagnostic systems using home pulse oximetry studies have failed to meet the accuracy requirements - particularly the low false normal rate (FNR) - required for a pre-PSG screening test. Thus the aim of this study is to investigate the feasibility of an OSA severity diagnostic system based on both oximetry and dual respiratory inductance plethysmography (RIP) bands. A total of 90 PSG studies (30 each of normal, mild/moderate and severe OSA) were retrospectively analyzed. Quantifications of oxygen desaturations (S), respiratory events (E) and heart rate arousals (A) were calculated and extracted and an empirical rule-based SEA classifier model for normal, mild/moderate and severe OSA defined and developed. In addition, an automated classifier using a decision tree algorithm was trained and tested using a 10-fold cross-validation. The empirical classification system showed a correct classification rate (CCR) of 0.83 (Cohen's Kappa κ=0.81, FNR=0.08), and the decision tree classifier achieved a CCR of 0.79 (κ=0.73, FNR=0.08) when compared to gold standard PSG assessment. The relatively high CCR, and low FNR indicate that a OSA severity system based on dual RIP and oximetry is feasible for application as a pre-PSG screening tool.

Sleep quality and effects of position on sleep apnea in East Asian children

OBJECTIVES

To assess whether obstructive sleep apnea syndrome (OSAS) affects sleep architecture and quality in East Asian children, and also to assess the effects of body position during sleep on respiratory disturbance during sleep.

MATERIALS AND METHODS

We enrolled 50 consecutive East Asian children with habitual snoring between 2007 and 2009. Nineteen children had OSAS (apnea-hypopnea index, AHI≥5; OSAS group) and 31 children were simple snorers (control group). They underwent polysomnography and physical examination of their nasal and oral cavities with a roentgenogram of the nasopharynx. Sleep architecture and other polysomnographic variables were compared between the OSAS and control groups. The effect of body position during sleep on respiratory disturbance was examined, and also in relation to obesity and adeno-tonsillar size.

RESULTS

There was a decrease in total sleep time and in sleep efficiency, as well as increased arousal and heart rate (P<0.05) in the OSAS group. Sub-analysis of AHI according to sleep posture showed that AHI is higher when the patient is in the supine position than in the non-supine position (P=0.032). The presence of OSAS and kissing tonsils were contributing factors to the positional difference in AHI (P<0.05). Obesity and adenoid hypertrophy did not affect the positional difference of AHI.

CONCLUSIONS

OSAS may have a greater influence on the sleep architecture of East Asian children, and East Asian children may have a higher AHI when sleeping in the supine position. Tonsillar hypertrophy and the presence of OSAS are possible contributing factors for positional difference of AHI in East Asian children.

The correlation between craniofacial morphology and sleep-disordered breathing in children in an undergraduate orthodontic clinic

PURPOSE

The aim of this study was to assess children in an orthodontic teaching clinic to determine the relationship between sleep-disordered breathing (SDB) symptoms and craniofacial morphology.

METHODS

All parents were asked to complete a SDB questionnaire at the commencement of orthodontic therapy. A cephalometric analysis included face heights, hyoid position, soft palate lengths, mandibular, vertical airway, overjet, and overbite. Study model measurements included dental width, depth, and palatal height. The subjects were divided into two groups according to their dentition stage: early or late mixed.

RESULTS

Data from 173 children (male 50.3%, mean age 10.1 ± 1.7 years) that completed the OSA-18 questionnaire and the cephalometric (CA) and model (MA) analyses were evaluated. The questionnaire suggested that only two children in the orthodontic pool had an increased chance of exhibiting SDB. However, loud snoring, mouth breathing, and difficulty awakening were reported in more than 20% of the children. Overall, a higher total score correlated with retroclined upper incisors (CA) and high palatal height (MA, p < 0.05). Although there was no significant score differences between the groups, a higher total score correlated with a long soft palate (CA, p < 0.05) in the early mixed dentition group and a high palatal height (MA) in the late mixed dentition group (p < 0.05).

CONCLUSION

Even though few patients were suspected as having SDB, symptoms were related to many cephalometric variables and study model measurements. Since the etiology of SDB is believed to involve multiple factors, such patients may exhibit some risk of developing SDB in the future.

Acute cardiovascular changes with obstructive events in children with sleep disordered breathing

STUDY OBJECTIVES

Obstructive apneas in adults are associated with acute changes in blood pressure (BP) and heart rate (HR) that may contribute to poor cardiovascular outcome. Children with sleep disordered breathing (SDB) are similarly at risk for cardiovascular complications. We aimed to test the hypothesis that BP and HR are augmented during obstructive events in children equivalent to levels reported in adults.

DESIGN

Beat-by-beat mean arterial pressure (MAP) and HR were analyzed over the course of obstructive events (pre, early, late, and post-event) during NREM and REM sleep and compared using 2-way ANOVA with post hoc analyses.

SETTING

Pediatric sleep laboratory.

PATIENTS OR PARTICIPANTS

30 children (15M/15F) aged 7-12 y referred for investigation of SDB INTERVENTIONS: N/A.

MEASUREMENTS AND RESULTS

All children underwent overnight polysomnography with continuous BP recording. MAP and HR increased significantly from late to post event in both sleep states (mean +/- SEM, NREM: MAP, 74 +/- 3 to 93 +/- 3 mm Hg; HR, 76 +/- 2 to 97 +/- 2 bpm. REM: MAP, 76 +/- 3 to 89 +/- 3 mm Hg; HR, 76 +/- 2 to 91 +/- 2 bpm. P < 0.05 for all). NREM sleep state and arousal from sleep were significant independent predictors of the magnitude of cardiovascular change from late to post event (P < 0.05 for all).

CONCLUSIONS

Children with SDB experience significant changes in HR and BP during obstructive events with magnitudes that are similar to levels reported in adults. These changes are more pronounced during NREM sleep and with arousal. These acute cardiovascular changes may have important implications for poor cardiovascular outcome in children with OSA as repetitive cardiovascular perturbations may contribute to the development of hypertension.

Perioperative management of children with obstructive sleep apnea

Obstructive sleep apnea syndrome (OSA) affects 1%-3% of children. Children with OSA can present for all types of surgical and diagnostic procedures requiring anesthesia, with adenotonsillectomy being the most common surgical treatment for OSA in the pediatric age group. Thus, it is imperative that the anesthesiologist be familiar with the potential anesthetic complications and immediate postoperative problems associated with OSA. The significant implications that the presence of OSA imposes on perioperative care have been recognized by national medical professional societies. The American Academy of Pediatrics published a clinical practice guideline for pediatric OSA in 2002, and cited an increased risk of anesthetic complications, though specific anesthetic issues were not addressed. In 2006, the American Society of Anesthesiologists published a practice guideline for perioperative management of patients with OSA that noted the pediatric-related risk factor of obesity, and the increased perioperative risk associated with adenotonsillectomy in children younger than 3 yr. However, management of OSA in children younger than 1 yr-of-age was excluded from the guideline, as were other issues related specifically to the pediatric patient. Hence, many questions remain regarding the perioperative care of the child with OSA. In this review, we examine the literature on pediatric OSA, discuss its pathophysiology, current treatment options, and recognized approaches to perioperative management of these young and potentially high-risk patients.

Severity assessment of obstructive sleep apnea syndrome (OSAS) in pediatric patients

OBJECTIVE

To assess obstructive sleep apnea syndrome (OSAS) severity among pediatric patients. Design. A retrospective review of charts and polysomnography (PSG) results.

MEASUREMENTS AND MAIN RESULTS

Apnea-hypopnea index (AHI) and the cumulative duration of sleep while O(2)SAT was <91% were determined in 389 patients with OSAS. Patients with AHI ranging <5, 5 to 15, 16 to 30, and >30, had mean lowest observed O(2)SAT values of 88% +/- 8%, 85% +/- 9%, 78% +/- 12%, and 69% +/- 13%, respectively. The patients spent a mean of 3.5% +/- 9.2 % of their sleep time with O(2)SAT < 91%. AHI values showed a poor linear correlation with the lowest measured O(2)SAT values. Body mass index percentiles showed no significant linear correlation with AHI values or with the lowest measured values of O(2)SAT.

CONCLUSION

Values of AHI cannot accurately predict severity of oxyhemoglobin desaturation in pediatric OSAS and vice versa. No significant correlation between body mass index percentiles and severity of OSAS was established.

Adenotonsillectomy for obstructive sleep apnoea in children

BACKGROUND

Current treatment of sleep apnoea in children consists of largely surgical based treatments. Adenotonsillectomy is the most commonly used intervention to treat sleep apnoea in children.

OBJECTIVES

To determine the efficacy of adenotonsillectomy in the treatment of obstructive sleep apnoea in children.

SEARCH STRATEGY

The Cochrane Airways Group Specialised Register was searched with pre-specified terms. Searches were current as of August 2008.

SELECTION CRITERIA

Randomised trials recruiting children with a diagnosis of obstructive sleep apnoea.

DATA COLLECTION AND ANALYSIS

Two reviewers examined the search results and collected data from the studies in terms of their characteristics before deciding which ones would be included in the review.

MAIN RESULTS

One study met the review entry criteria. This study addressed the relative merits of two surgical techniques in treating OSA in children (temperature controlled radiofrequency tonsillectomy and adenoidectomy, and complete tonsillectomy and adenoidectomy). No significant difference was apparent for either symptoms or respiratory disturbance index. More children in the TCFR&A group were able to return to normal diet at 7 days compared with complete T&A. No significant complications were observed in the study.

AUTHORS' CONCLUSIONS

One small study failed to find a difference between two surgical techniques, although return to normal diet was more frequent in the group treated by temperature controlled radiofrequency tonsillectomy and adenoidectomy. At present there is still debate as to the criteria required to diagnose significant obstructive sleep apnoea in children. Also the natural history of the condition has not been fully delineated. There is an absence of randomised controlled trials investigating the efficacy of treatment of confirmed obstructive sleep apnoea with adenotonsillectomy in children. Research is required before recommendations for the treatment of obstructive sleep apnoea in children can be formulated. The quality of research in this area could be improved with the use of sleep studies at baseline to determine the extent of severity of sleep apnoea in children who are recruited to studies in this area. Long-term follow up is also required in order to explore the effect of adenotonsillectomy on paediatric sleep apnoea.

Sleep associated gas exchange abnormalities in children and adolescents with habitual snoring

STUDY OBJECTIVES

The purpose of this study was to describe the prevalence of polysomnographically diagnosed OSAS and to describe the severity of sleep associated gas exchange abnormalities (SAGEA) in habitually snoring children. We hypothesized that there would be a high prevalence of OSAS in obese children with habitual snoring and that the most overweight children would have the most significant SAGEA.

DESIGN

Retrospective chart review.

MEASUREMENTS AND RESULTS

Nocturnal polysomnography (NPSG) data from 114 children and adolescents referred for habitual snoring were examined. 74 of the subjects were male (65%), average age of 9.78 +/- 4.19 years, average AHI 13.51 +/- 20.25, mean BMI z-score 1.79 +/- 1.18. BMI z-scores correlated positively with severity of OSAS (P < 0.05) such that children with progressive degrees of obesity had more frequent respiratory events during sleep. Additionally, severity of sleeping hypercapnea as measured by percent of total sleep time with EtCO(2) values above 50 mm Hg was more severe with progressive degrees of obesity. Likewise, all measures of oxyhemoglobin desaturation were more severe with progressive degrees of obesity. Positive correlations between the severity of SAGEA and degree of obesity remained even after controlling for the severity of OSAS.

CONCLUSIONS

OSAS is highly prevalent in children referred to a pediatric sleep center with complaints of habitual snoring across a wide spectrum of weight categories. SAGEA increases with progressive obesity even when controlling for the severity of OSAS suggesting that obesity is an independent risk factor for SAGEA. Furthermore, because obese children frequently have SAGEA, capnography should be obtained during NPSG when possible.

Is there a clear link between overweight/obesity and sleep disordered breathing in children?

The proportion of children who are overweight or obese has risen steadily in recent decades and approaches a quarter of all children in Western countries. This global epidemic of excess weight and adiposity in humans is associated with increased morbidity and mortality, especially related to diabetes and poor cardiovascular health. It would appear that obesity is also generally accepted to be an important risk factor in the development of sleep disordered breathing (SDB), in children as well as adults. The article, "The prevalence, anatomical correlates and treatment of sleep-disordered breathing in obese children and adolescents", by Verhulst et al., also in this issue, reviews evidence supporting the view that obese children are at higher risk of developing SDB. We believe, however, that the available studies do not support a straightforward association of overweight or obesity with increased prevalence of SDB. Rather, the available data is clearly equivocal mainly due to methodological differences between the previous studies. This review nonetheless examines the factors which may modulate the relationship between overweight or obesity and prevalence of SDB, particularly ethnicity and age.

Polysomnographic values in children undergoing puberty: pediatric vs. adult respiratory rules in adolescents

STUDY OBJECTIVES

Polysomnographic respiratory events in children should be scored using pediatric respiratory rules. However, due to a lack of data on adolescents, recently revised rules allow children aged 13-18 years to be scored by adult or pediatric criteria. To clarify which criteria to use, we describe the evolution of respiratory events with Tanner stage, and we compare events in children aged 13-18 years with the new American Academy of Sleep Medicine adult and pediatric respiratory rules.

DESIGN

Cross-sectional

SETTING

Academic hospital

PARTICIPANTS

Healthy subjects aged 8-18 years recruited for research purposes.

INTERVENTIONS

Physical examination to determine Tanner stage, overnight polysomnogram, and determination of sex hormones.

RESULTS

Sixty-eight subjects (Tanner 1-5) were studied, mean age [SD] = 13 +/- 3 years, median apnea hypopnea index (AHI)= 0.1 (range: 0-1.2)/h. The median percentages of total sleep time (TST) with SpO2 < 92% were 0.1 (0-4.2)%, and with end-tidal CO2 > 50 torr was 0.1 (0-88.6)%. Thirty-two subjects were aged 13-18 years, (Tanner 3-5). The difference between AHI scored by pediatric (median = 0 [0-0.9]/h) and adult (median = 0 [0 - 0.5]/h) criteria was statistically significant (P = 0.043), but not clinically relevant.

CONCLUSIONS

Respiratory events in normal children aged 8-18 years are rare and unrelated to Tanner stage. Adult or pediatric respiratory rules can be used for scoring polysomnograms in asymptomatic subjects approaching adulthood. Further studies are needed in symptomatic children within this age group.

Dental arch morphology in children with sleep-disordered breathing

The aim of the present study was to examine the effects of nocturnal breathing disorders such as obstructive sleep apnoea (OSA) and snoring on developing dental arches. The study group comprised 41 children (22 males, 19 females, mean age 7.2 years, standard deviation 1.93) with diagnosed OSA. Age- and gender-matched groups of 41 snoring and 41 non-obstructed control children were selected. Orthodontic examination was carried out and dental impressions were taken. Malocclusions were diagnosed clinically and 13 linear variables were measured from the dental casts. The differences between the dental arch measurements of the OSA, snoring, and control groups were studied using analysis of variance followed by Duncan's multiple comparison method. Children with diagnosed OSA had a significantly increased overjet, a reduced overbite, and narrower upper and shorter lower dental arches when compared with the controls. Snoring children had similar but not as significant differences as OSA children when compared with the controls. There were more children with an anterior open bite (AOB) in the OSA group (P=0.016) and with a Class II or asymmetric molar relationship in the groups of OSA (P=0.013) and snoring (P=0.004) subjects compared with the non-obstructed controls. There were more subjects with mandibular crowding (P=0.002) and with an AOB (P=0.019) with an increasing obstructive apnoea-hypopnoea index (AHI). These findings are in agreement with previous studies of the effects of increased upper airway resistance on dental arch morphology and can be explained by long-term changes in the position of the head, mandible, and tongue in order to maintain airway adequacy during sleep.

Sleep-disordered breathing in children with metabolic syndrome: the role of leptin and sympathetic nervous system activity and the effect of continuous positive airway pressure

OBJECTIVE

The purpose of this work was to determine whether, in children with metabolic syndrome and sleep-disordered breathing, metabolic markers separate them from children with metabolic syndrome without sleep-disordered breathing and whether treatment of sleep-disordered breathing with continuous positive airway pressure is associated with an improvement in metabolic derangement.

PATIENTS AND METHODS

Subjects aged 7 to 19 years old with metabolic syndrome and a positive validated sleep questionnaire were recruited. Subjects underwent overnight polysomnography, during which sympathetic nervous system activity was assessed via 8-hourly measurements of norepinephrine and epinephrine, together with leptin. The next morning, a fasting 3-hour oral glucose-tolerance test was performed to calculate whole-body insulin sensitivity. A fasting lipid panel interleukin 6, adiponectin, and C-reactive protein levels were also measured. Children with sleep-disordered breathing were placed on continuous positive airway pressure for 3 months and studied again. Sleep-disordered breathing and no sleep-disordered breathing groups were compared by using Fisher's exact test and t test for independent samples with analysis of covariance to adjust for age and BMI.

RESULTS

Of 34 children studied, 25 had sleep-disordered breathing (apnea-hypopnea index: >1.5). Mean hourly norepinephrine and leptin levels were higher in the group with sleep-disordered breathing compared with the group without sleep-disordered breathing (P < .005), with no difference in whole-body insulin sensitivity. Eleven subjects with sleep-disordered breathing completed 3 months of nightly continuous positive airway pressure treatment. In the follow-up study, mean hourly leptin levels were significantly lower than in the initial study, with no change in BMI z score or other measurements.

CONCLUSION

Our findings support the hypothesis that sleep-disordered breathing in children with metabolic syndrome is associated with increased sympathetic nervous system activity and leptin levels but not worsening of insulin resistance. Treatment of sleep-disordered breathing with continuous positive airway pressure led to a significant decrease in leptin levels.