[Reliability of respiratory polygraphy for the diagnosis of sleep apnea-hypopnea syndrome in children]

Diagnosis and Treatment of Sleep Apnea in Children: A Future Perspective Is Needed

Obstructive sleep apnea (OSA) in children is a prevalent, but still, today, underdiagnosed illness, which consists of repetitive episodes of upper airway obstruction during sleep with important repercussions for sleep quality. OSA has relevant consequences in the pediatric population, mainly in the metabolic, cardiovascular (CV), and neurological spheres. However, contrary to adults, advances in diagnostic and therapeutic management have been scarce in the last few years despite the increasing scientific evidence of the deleterious consequences of pediatric OSA. The problem of underdiagnosis and the lack of response to treatment in some groups make an update to the management of OSA in children necessary. Probably, the heterogeneity of OSA is not well represented by the classical clinical presentation and severity parameters (apnea/hypopnea index (AHI)), and new strategies are required. A specific and consensus definition should be established. Additionally, the role of simplified methods in the diagnosis algorithm should be considered. Finally, the search for new biomarkers for risk stratification is needed in this population. In conclusion, new paradigms based on personalized medicine should be implemented in this population.

Pediatric Obstructive Sleep Apnea: What’s in a Name?

Obstructive sleep apnea is a highly prevalent disease across the lifespan and imposes substantial morbidities, some of which may become irreversible if the condition is not diagnosed and treated in a timely fashion. Here, we focus on the clinical and epidemiological characteristics of pediatric obstructive sleep apnea, describe some of the elements that by virtue of their presence facilitate the emergence of disrupted sleep and breathing and its downstream consequences, and also discuss the potential approaches to diagnosis in at-risk children.

Automatic Sleep Staging in Children with Sleep Apnea using Photoplethysmography and Convolutional Neural Networks

Sleep staging is of paramount importance in children with suspicion of pediatric obstructive sleep apnea (OSA). Complexity, cost, and intrusiveness of overnight polysomnography (PSG), the gold standard, have led to the search for alternative tests. In this sense, the photoplethysmography signal (PPG) carries useful information about the autonomous nervous activity associated to sleep stages and can be easily acquired in pediatric sleep apnea home tests with a pulse oximeter. In this study, we use the PPG signal along with convolutional neural networks (CNN), a deep-learning technique, for the automatic identification of the three main levels of sleep: wake (W), rapid eye movement (REM), and non-REM sleep. A database of 366 PPG recordings from pediatric OSA patients is involved in the study. A CNN architecture was trained using 30-s epochs from the PPG signal for three-stage sleep classification. This model showed a promising diagnostic performance in an independent test set, with 78.2% accuracy and 0.57 Cohen's kappa for W/NREM/REM classification. Furthermore, the percentage of time in wake stage obtained for each subject showed no statistically significant differences with the manually scored from PSG. These results were superior to the only state-of-the-art study focused on the analysis of the PPG signal in the automated detection of sleep stages in children suffering from OSA. This suggests that CNN can be used along with PPG recordings for sleep stages scoring in pediatric home sleep apnea tests.

Home respiratory polygraphy in obstructive sleep apnea syndrome in children: Comparison with a screening questionnaire

OBJECTIVES

The prevalence of obstructive sleep apnea syndrome (OSAS) in children referred for sleep-disordered breathing reaches up to 59%. We aimed to test the adequacy of a questionnaire compared to home respiratory polygraphy (HRP), in 45 subjects (5-16 years-old), without maxillofacial malformations nor other comorbidities, presenting with symptoms compatible with OSAS.

METHODS

All children passed a 12-items questionnaire (Obstructive Airway Child test: OACT) and the HRP. OSAS was classified in severity according to the apnea-hypopnea index (AHI).

RESULTS

With HRP, 60% and 15% children were detected to have at least mild (AHI ≥1) and moderate (AHI >5) OSAS, respectively. The sensitivity of the questionnaire to detect mild and moderate OSAS was good (93% and 71%, respectively) but the specificity was very low (11% and 34%). However, an OACT score under 61 showed a very good negative predictive value for moderate and severe OSAS (87%). With the questionnaire, we could have avoided a complementary PSG or HRP in 25/45 (56%) of our subjects as in children with mild OSAS and without comorbidities only clinical observation is usually advised.

CONCLUSIONS

The OACT questionnaire has shown to be a good and quick instrument to exclude moderate and severe OSAS in our population of children without maxillofacial malformations. Indeed children scoring under 61 could avoid a constraining and expensive sleep exam. However, if the score is above this cut-off, the performance to recognize OSAS is low and the child's evaluation must be completed by a HRP or PSG.

Normal values for respiratory sleep polygraphy in children aged 4 to 9 years at 2,560 m above sea level

Obstructive sleep apnea syndrome affects 1%-4% of all children worldwide. Currently, diagnosis of obstructive sleep apnea is based on sea-level guidelines, without taking into account the altitude at which the populations live. It has been shown that at 3,200 m of altitude there is an increase in obstructive events in healthy children aged 7 to 16 years; on the other hand, it is known that SpO₂ dispersion between individuals becomes wider as altitude increases, a phenomenon that is more marked during sleep. About 17 million Colombians live in regions between 2,500 m and 2,700 m, as do significant populations in other Latin American countries. This research aimed to characterize respiratory polygraphy sleep parameters in healthy, non-snoring children aged 4-9 years living at 2,560 m. We carried out home respiratory polygraphy in 32 children with a mean age of 6.2 years (range 4-9 years). The average recorded sleep time was 7.8 h, the median apnea-hypopnea index was 9.2/h, the obstructive apnea-hypopnea index had a median of 8.8/h (p5 4.2 to p95 17.9) and central apnea a median of 0.4/h. The median SpO₂ was 93% (p5 90.5 to p95 94) and transcutaneous CO₂ had a median of 39.4 mmHg (p531.7 to p95 42.3). The median oxygen desaturation index ≥ 3% was 11.2 and median oxygen desaturation index ≥ 4% was 3.9. Normal measurements for respiratory polygraphy obtained at sea level do not apply to children at altitude. If such guidelines are used, obstructive sleep apnea will be over-diagnosed, resulting in unnecessary adenotonsillectomies, among other interventions.

Cardiorespiratory sleep studies at home: experience in research and clinical cohorts

OBJECTIVE

To evaluate the success rates of home cardiorespiratory polygraphy in children under investigation for sleep-disordered breathing and parent perspectives on equipment use at home.

DESIGN

Prospective observational study.

SETTING

Sheffield, Evelina London and Southampton Children's Hospitals.

PATIENTS

Data are reported for 194 research participants with Down syndrome, aged 0.5-5.9 years across the three centres and 61 clinical patients aged 0.4-19.5 years from one centre, all of whom had home cardiorespiratory polygraphy including respiratory movements, nasal pressure flow, pulse oximetry, body position and motion.

MAIN OUTCOME MEASURES

Percentage of home cardiorespiratory studies successfully acquiring ≥4 hours of artefact-free data at the first attempt. Parental report of ease of use of equipment and preparedness to repeat home diagnostics in the future.

RESULTS

143/194 (74%; 95% CI 67% to 79%) of research participants and 50/61 (82%; 95% CI 71% to 90%) of clinical patients had successful home cardiorespiratory polygraphy at the first attempt. Some children required multiple attempts to achieve a successful study. Overall, this equated to 1.3 studies per research participant and 1.2 studies per clinical child. The median artefact-free sleep time for successful research studies was 515 min (range 261-673) and for clinical studies 442 min (range 291-583). 84% of research and 87% of clinical parents expressed willingness to repeat home cardiorespiratory polygraphy in the future. 67% of research parents found the equipment 'easy or okay' to use, while 64% of clinical parents reported it as 'easy' or 'very easy'.

CONCLUSIONS

Home cardiorespiratory polygraphy offers an acceptable approach to the assessment of sleep-disordered breathing in children.

Automated analysis of nocturnal oximetry as screening tool for childhood obstructive sleep apnea-hypopnea syndrome

Childhood obstructive sleep apnea-hypopnea syndrome (OSAHS) is a highly prevalent condition that negatively affects health, performance and quality of life of infants and young children. Early detection and treatment improves neuropsychological and cognitive deficits linked with the disease. The aim of this study was to assess the performance of automated analysis of blood oxygen saturation (SpO2) recordings as a screening tool for OSAHS. As an initial step, statistical, spectral and nonlinear features were estimated to compose an initial feature set. Then, fast correlation-based filter (FCBF) was applied to search for the optimum subset. Finally, the discrimination power (OSAHS negative vs. OSAHS positive) of three pattern recognition algorithms was assessed: linear discriminant analysis (LDA), quadratic discriminant analysis (QDA) and logistic regression (LR). Three clinical cutoff points commonly used in the literature for positive diagnosis of the disease were applied: apnea-hypopnea index (AHI) of 1, 3 and 5 events per hour (e/h). Our methodology reached 88.6% accuracy (71.4% sensitivity and 100.0% specificity, 100.0% positive predictive value, and 84.0% negative predictive value) in an independent test set using QDA for a clinical cut-off point of 5 e/h. These results suggest that SpO2 nocturnal recordings may be used to develop a reliable and efficient screening tool for childhood OSAHS.

Devices for home detection of obstructive sleep apnea: A review

One of the most common sleep-related disorders is obstructive sleep apnea, characterized by a reduction of airflow while breathing during sleep and cause significant health problems. This disorder is mainly diagnosed in sleep labs with polysomnography, involving high costs and stress for the patient. To address this situation multiple systems have been proposed to conduct the examination and analysis in the patient's home, using sensors to detect physiological signals that are examined by algorithms. The objective of this research is to review publications that show the performance of different devices for ambulatory diagnosis of sleep apnea. Commercial systems that were examined by an independent research group and validated research projects were selected. In total 117 articles were analysed, including a total of 50 commercial devices. Each article was evaluated according to diagnostic elements, level of automatisation implemented and the deducted level of evidence and quality rating. Each device was categorized using the SCOPER categorization system, including an additional proposed category, and a final comparison was performed to determine the sensors that provided the best results.

Evaluation of upper airway obstruction in infants with Pierre Robin sequence and the role of polysomnography--Review of current evidence

Pierre Robin sequence (PRS) is a heterogeneous condition presenting with upper airway obstruction (UAO) of varying severity. Polysomnography (PSG) is an objective investigation to assess the severity of obstructive sleep apnea and UAO. Its role in the management of PRS has not been well defined. This review summarizes the available evidence on the role of PSG in the assessment of infants with PRS in the context of other commonly used methods of assessment.

Pediatric Home Sleep Apnea Testing: Slowly Getting There!

Pediatric OSA can result in significant neurocognitive, behavioral, cardiovascular, and metabolic morbidities. Prompt diagnosis and treatment are, therefore, of paramount importance. The current gold standard for diagnosis of OSA in children is in-laboratory polysomnography (PSG). Home sleep apnea testing has been considered as an alternative as it is potentially more cost effective, convenient, and accessible. This review concentrates mainly on the use of type 2 and 3 portable monitoring devices. The current evidence on the feasibility and diagnostic accuracy of home testing in the diagnosis of pediatric OSA was examined. Overall, the evidence in children is limited. Feasibility studies that have been performed have on the whole shown good results, with several reporting > 90% of their home recordings as meeting predetermined quality criteria regarding signal artifact and minimum recording time. The limited data comparing type 2 studies with in-laboratory PSG have shown no significant differences in respiratory parameters. The results pertaining to diagnostic accuracy of type 3 home sleep apnea testing devices are conflicting. Although more research is needed, home testing with at least a type 3 portable monitor offers a viable alternative in the diagnosis of otherwise healthy children with moderate to severe OSA, particularly in settings where access to polysomnography is scarce or unavailable. Of note, since most studies have been performed in habitually snoring healthy children, home sleep apnea testing may not be applicable to children with other comorbid conditions. In particular, CO2 monitoring is important in children in whom there is concern regarding nocturnal hypoventilation, such as children with neuromuscular disease, underlying lung disease, or obesity hypoventilation, and most home testing devices do not include a transcutaneous or end-tidal CO2 channel.

Predicting poor school performance in children suspected for sleep-disordered breathing

OBJECTIVE

Habitually snoring children are at a greater risk of poor school performance (PSP). We investigated the ability of conventional sleep-disordered breathing (SDB) measures for predicting PSP in habitually snoring children.

METHODS

The dataset of Hannover Study on Sleep Apnea in Childhood (HASSAC), a large community-based study in primary school children, was retrospectively analyzed. All habitual snorers were included. Based on their grades, children were grouped into good and poor school performers. SDB measures obtained by a parental questionnaire, a home pulse oximetry, and a home polysomnography were evaluated for their accuracy in predicting poor school performance by calculating receiver operating characteristic curves and area under this curve (AUC). The most predictive single factors were identified and entered into a prediction model.

RESULTS

Of 114 habitual snorers (mean age 9.6 years, 51 boys), 59 had PSP. All investigated SDB measures showed low accuracy (ie, AUC <0.8). The highest AUC observed was 0.686 for a questionnaire score, 0.565 for an oximetry factor, and 0.624 for a polysomnography factor. Of 20 single significant predictors for PSP, five were selected for inclusion into a prediction model. The model reached an unadjusted AUC of 0.826 and an adjusted AUC of 0.851.

CONCLUSIONS

Conventional SDB measures obtained with questionnaire, oximetry, or polysomnography may not be sufficiently predictive of PSP in children suspected for SDB. However, combining factors in a clinical prediction model may improve prediction. Results of such a model may be used to assess the risk of developing neurocognitive impairment and to decide whether a child suspected for SDB might benefit from treatment.

Reliability of home respiratory polygraphy for the diagnosis of sleep apnea in children

OBJECTIVE

The objective of this study was to evaluate the diagnostic reliability of home respiratory polygraphy (HRP) in children with a clinical suspicion of OSA-hypopnea syndrome (OSAS).

METHODS

A prospective blind evaluation was performed. Children between the ages of 2 to 14 years with clinical suspicion of OSAS who were referred to the Sleep Unit were included. An initial HRP followed by a later date, same night, in-laboratory overnight respiratory polygraphy and polysomnography (PSG) in the sleep laboratory were performed. The apnea-hypopnea index (AHI)-HRP was compared with AHI-PSG, and therapeutic decisions based on AHI-HRP and AHI-PSG were analyzed using intraclass correlation coefficients, Bland-Altman plots, and receiver operator curves (ROCs).

RESULTS

Twenty-seven boys and 23 girls, with a mean age of 5.3 ± 2.5 years, were studied, and 66% were diagnosed with OSAS based on a PSG-defined obstructive respiratory disturbance index ≥ 3/h total sleep time. Based on the availability of concurrent HRP-PSG recordings, the optimal AHI-HRP corresponding to the PSG-defined OSAS criterion was established as ≥ 5.6/h The latter exhibited a sensitivity of 90.9% (95% CI, 79.6%-100%) and a specificity of 94.1% (95% CI, 80%-100%).

CONCLUSIONS

HRP recordings emerge as a potentially useful and reliable approach for the diagnosis of OSAS in children. However, more research is required for the diagnosis of mild OSAS using HRP in children.

Update on the use of portable monitoring system for the diagnosis of sleep apnea in specific population

The prevalence and severity of obstructive sleep apnea (OSA) is higher in specific population: children, elderly, obese and patients with pulmonary and cardiovascular diseases, compared to the general population. OSA is associated with greater morbidity and mortality in these patients. Although full-night polysomnography is still the gold standard diagnostic sleep study for OSA, it is a time consuming, expensive and technically demanding exam. Over the last few years, there is growing evidence on the use of portable monitors (PM) as an alternative for the diagnosis of OSA. These devices were developed specially for sleep evaluation at home, at a familiar environment, with easy self-application of monitoring, unattended. The use of PM is stablished for populations with high pre-test probability of OSA. However, there is a lack of studies on the use of PM in age extremes and patients with comorbidities. The purpose of this review is to present the studies that evaluated the use of PM in specific population, as well as to describe the advantages, limitations and applications of these devices in this particular group of patients. Although the total loss rate of recordings is variable in different studies, the agreement with full-night polysomnography justifies the use of PM in this population.

Exploring the spectral information of airflow recordings to help in pediatric Obstructive Sleep Apnea-Hypopnea Syndrome diagnosis

This work aims at studying the usefulness of the spectral information contained in airflow (AF) recordings in the context of Obstructive Sleep Apnea-Hypopnea Syndrome (OSAHS) in children. To achieve this goal, we defined two spectral bands of interest related to the occurrence of apneas and hypopneas. We characterized these bands by extracting six common spectral features from each one. Two out of the 12 features reached higher diagnostic ability than the 3% oxygen desaturation index (ODI3), a clinical parameter commonly used as screener for OSAHS. Additionally, the stepwise logistic regression (SLR) feature-selection algorithm showed that the information contained in the two bands was complementary, both between them and with ODI3. Finally, the logistic regression method involving spectral features from the two bands, as well as ODI3, achieved high diagnostic performance after a bootstrap validation procedure (84.6±9.6 sensitivity, 87.2±9.1 specificity, 85.8±5.2 accuracy, and 0.969±0.03 area under ROC curve). These results suggest that the spectral information from AF is helpful to detect OSAHS in children.

Statistical and nonlinear analysis of oximetry from respiratory polygraphy to assist in the diagnosis of Sleep Apnea in children

Obstructive Sleep Apnea-Hypopnea Syndrome (OSAHS) is a sleep related breathing disorder that has important consequences in the health and development of infants and young children. To enhance the early detection of OSAHS, we propose a methodology based on automated analysis of nocturnal blood oxygen saturation (SpO(2)) from respiratory polygraphy (RP) at home. A database composed of 50 SpO(2) recordings was analyzed. Three signal processing stages were carried out: (i) feature extraction, where statistical features and nonlinear measures were computed and combined with conventional oximetric indexes, (ii) feature selection using genetic algorithms (GAs), and (iii) feature classification through logistic regression (LR). Leave-one-out cross-validation (loo-cv) was applied to assess diagnostic performance. The proposed method reached 80.8% sensitivity, 79.2% specificity, 80.0% accuracy and 0.93 area under the ROC curve (AROC), which improved the performance of single conventional indexes. Our results suggest that automated analysis of SpO(2) recordings from at-home RP provides essential and complementary information to assist in OSAHS diagnosis in children.

Overnight polysomnography versus respiratory polygraphy in the diagnosis of pediatric obstructive sleep apnea

BACKGROUND

Substantial discrepancies exist in the type of sleep studies performed to diagnose pediatric obstructive sleep apnea (OSA) in different countries. Respiratory polygraphic (RP) recordings are primarily performed in sleep laboratories in Europe, whereas polysomnography (PSG) constitutes the majority in the US and Australia. Home RP show consistent apnea-hypopnea index (AHI) underscoring, primarily because the total recording time is used as the denominator when calculating the AHI compared to total sleep time (TST). However, laboratory-based RP are less likely affected, since the presence of sleep technicians and video monitoring may enable more accurate TST estimates. We therefore examined differences in AHI in PSG and in-lab RP, and whether RP-based AHI may impact clinical decision making.

METHODS

Of all the children assessed for possible OSA who underwent PSG evaluation, 100 were identified and divided into 4 groups: (A) those with AHI < 1/h TST (n = 20), (B) 1 ≤ AHI < 5/h TST (n = 40), (C) 5 ≤ AHI < 10/h TST (n = 20), and (D) AHI ≥ 10/h TST (n = 20). Electroencephalography, electrooculography, and electromyography channels were deleted from the original unscored recordings to transform them into RP, and then rescored in random sequence. AHI-RP were compared to AHI-PSG, and therapeutic decisions based on AHI-RP and AHI-PSG were formulated and analyzed using clinical details derived from the patient's clinic letter.

RESULTS

Bland Altman analysis showed that in lab RP underestimated the AHI despite more accurate estimates of TST. This underestimation was due to missed hypopneas causing arousals without desaturation. Basing the therapeutic management decision on RP instead of PSG results changed the clinical management in 23% of all patients. The clinical management for patients in groups A and D was unaffected. However, 27.5% of patients in group B would have been given no treatment, as they would be diagnosed as having no OSA (AHI < 1/h TST) when they should have received a trial of anti-inflammatory therapy or been referred for ear, nose, and throat (ENT) review. Sixty percent of patients in group C would have received either a trial of medical treatment to treat mild OSA or no treatment, instead of referral to ENT services or commencement of continuous positive airway pressure.

CONCLUSION

Apnea-hypopnea index (AHI) is underestimated in respiratory polygraphy (RP), and the disparity in AHI-RP and AHI-polysomnography can significantly affect clinical management decisions, particularly in children with mild and moderate obstructive sleep apnea (1 < AHI < 10/h total sleep time).

Feasibility of unattended home polysomnography in children with sleep-disordered breathing

OBJECTIVE

To investigate the technical feasibility of unattended polysomnography (HPSG) for diagnosis of obstructive sleep apnea (OSA) in children.

METHODS

A single-night HPSG was performed on children referred to the pediatric respiratory laboratory. Non-interpretable HPSGs were defined as: recordings with (i) loss of ≥2 of the following channels: nasal flow, or thoraco-abdominal belts, or (ii) HPSG with less than 4 h of artifact-free recording time or (iii) less than 4 h SpO2 signal.

RESULTS

Of n = 101 included HPSGs, n = 75 were ambulatory and n = 26 in hospitalized subjects. Median (minimum-maximum) age was 2.8 (0-15.4) years. Interpretable and technically acceptable recordings were obtained in 94 subjects (93%). Only 7 recordings (4 at home versus 3 in hospitalized subjects, p-value = 0.254) were classified as non-interpretable and had to be repeated. Artifact-free recording time was 461 (23-766)min. Complete artifact-free pulse oximetry signal was obtained in 14% of the included subjects. Neither age, gender, AHI, nor place of performance was significantly associated with the interpretability of recordings.

DISCUSSION

HPSG showed a high rate of interpretability and technical acceptance. The high technical feasibility obtained by HPSG may help to improve simple screening tests for OSA in children.

Screening for symptoms of obstructive sleep apnea in children with severe craniofacial anomalies: assessment in a multidisciplinary unit

OBJECTIVE

To assess the incidence of airway obstruction symptoms and the presence of obstructive sleep apnea in children with severe craniofacial anomalies by a proactive screening program using a standard questionnaire and cardiorespiratory polygraphy.

PATIENTS AND METHODS

Children with severe craniofacial anomalies referred to our paediatric airway unit from February 2001 to June 2011 were eligible to be included in this retrospective, single centre study. Symptoms of airway obstruction were proactively investigated using the shorter version of the Pediatric Sleep Questionnaire (PSQ). Obstructive sleep apnea was assessed by means of cardiorespiratory polygraphy. Demographic data and reason for referral were also recorded. Primary outcomes were the prevalence of symptoms of airway obstruction and OSA.

RESULTS

44 children (24 girls) with severe craniofacial anomalies (15 Crouzon, 13 Apert, 9 Goldenhar, 5 Treacher-Collins, 2 Pfeiffer) were included, at a mean age of 5 years (range 8 months to 14 years). Reason for referral was routine follow up in 30 patients and overt OSA symptoms and signs in the remaining 14. PSQ results showed symptoms of airway obstruction in 82% of patients, being snoring the most frequent symptom (64.1%) followed by apneas (33.3%). Polygraphic studies showed inconclusive results in 8 children (18.2%), normal apnea-hypopnea index (AHI) in 16 (36.4%), mild obstructive sleep apnea in 9 (20.4%), moderate in 4 (9.1%) and severe obstructive sleep apnea in 7 (15.9%).

CONCLUSIONS

Children with craniofacial anomalies have a high prevalence of symptoms of airway obstruction and obstructive sleep apnea that support a proactive screening strategy in this highly selected population.

Respiratory polygraphy for follow-up of obstructive sleep apnea in children

OBJECTIVES

(1) To evaluate the effectiveness of adenotonsillectomy for the treatment of Obstructive Sleep Apnea Hypopnea Syndrome (OSAHS) in children. (2) To evaluate the usefulness of respiratory polygraphy (RP) for controlling post-adenotonsillectomy effects.

METHODS

The children studied were referred to the Burgos Sleep Unit (SU) with clinical suspicion of OSAHS before undergoing adenotonsillectomy. For all patients, a clinical history was taken and a general physical examination, as well as a specific ear, nose, and throat examination was done. RP before adenotonsillectomy, and seven months afterwards, was also done. OSAHS was diagnosed if the Apnea Hypopnea Index (AHI) was ≥ 4.6.

RESULTS

Of the 100 children studied, 68 were male and 32 female, with an age of 4.17 ± 2.05 years. Using RP, 86 of them were diagnosed with OSAHS before undergoing adenotonsillectomy. There was a significant improvement in all clinical and polygraphic variables after adenotonsillectomy. The pre and post surgery AHI index was 11.9 ± 11.0 and 2.6 ± 1.5, respectively, with a significant mean difference (9.4 ± 10.9, p<0.01). The residual OSAHS was 11.6% (CI 95%: 4.3-19%).

CONCLUSIONS

Respiratory polygraphy is a useful tool for monitoring the effectiveness of surgical treatment and the detection of residual OSAHS in children with adenotonsillar hypertrophy.