[Home cardiorespiratory sleep study in children. Will it be feasible?]

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.

Utility of the pediatric sleep questionnaire and pulse oximetry as screening tools in pediatric patients with suspected obstructive sleep apnea syndrome

Objective. To assess the screening tools in snoring patients. Material and Methods. A retrospective review of data was conducted from children between 2 and 15 years old who were referred on suspicion of obstructive sleep apnea-hypopnea (OSAH) between June 2008 and June 2011. We excluded patients with significant comorbidities. Pediatric Sleep Questionnaire (PSQ), physical exam (PE), and pulse-oximetry data were collected and correlated with the results of the nightly polygraph at home. Results. We selected 98 patients. The 22-item version of the PSQ had sensitivity of 96% and specificity of 36.8%. The overall value of the clinic predictor of OSAH (PSQ and PE together) exhibited an increased specificity 57.6% with 94.6% of sensitivity. The nocturnal home oximetry method used alone was very specific, 92.1%, but had a lower sensitivity, 77.1%. The set of clinical assessment tools used together with pulse-oximetry screening provided excellent specificity 98.1% and a positive predictive value 94.1% globally. The performance of this screening tool is related with the severity of OSAH and accuracy is better in moderate and severe cases. Conclusion. The combination of clinical assessment and pulse-oximetry screening can provide a sufficient diagnostic approach for pediatric patients with suspected OSAH at least in moderate and severe cases.

[Diagnostic utility of nocturnal in-home respiratory polygraphy]

INTRODUCTION

Sleep apnea-hypopnea syndrome (SAHS) is relatively frequent in children. The gold standard for diagnosis is polysomnography. However, because of technical difficulties and the cost of this method, new alternatives have become available, such as respiratory polygraphy (RP) performed at home or in hospital, which have provided satisfactory results in children with clinical suspicion of SAHS.

OBJECTIVE

The aim of this study was to analyze the diagnostic utility of in-home RP in the diagnosis of SAHS in a sample of boys and girls referred to the pediatric respiratory care department for suspected sleep apnea, snoring, or both.

MATERIAL AND METHODS

In all patients, a history and physical examination were performed; X-ray of the chest and cavum and RP were carried out. The following qualitative variables were analyzed: place where RP was performed, the result, sex, the reason for consulting, place of residence, results of otorhinolaryngological examination, and treatment. The quantitative variables analyzed were age, total number of apneas, total number of hypopneas, apnea index/hour, hypopnea index/hour, mean and minimum SpxO2, number of snores per hour and the snore index/hour. Statistical analysis was performed using Pearson's chi-square test and Student's t-test.

RESULTS

A total of 132 patients were studied, 44 (33.3 %) through in-home RP (group 1) and 88 (66.6 %) through in-hospital RP (group 2). In group 1, two recordings (4.5 %) were considered nonvalid. The mean age of the patients was 8.3 years (SD 3.02). The results [means (standard deviation)] of in-home RP were as follows: apnea-hypopnea index (AHI)/h: 3.4 (4.3); mean SpxO2: 97.3 (1.8); minimum SpxO2: 87.7 (10.3). In group 2, four recordings (4.5 %) were nonvalid. The mean age of the patients was 7.4 years (SD 3). The results of in-hospital RP were as follows: AHI/h: 4.45 (5.4); mean SpxO2: 96.8 (1.8); minimum SpxO2: 87 (11). No significant differences were found between the validity of in-home and in-hospital RP. Likewise, no significant differences were found between AHI/h, SpxO2 and in-home and in-hospital RP.

CONCLUSION

In conclusion, in our sample, the diagnostic utility of in-home RP was equal to that of in-hospital RP. In-home RP allows the possibility of performing a more physiological sleep study and, by eliminating the cost of hospitalization, is more cost-efficient. Therefore, in-home RP is a valid and reliable technique for the diagnosis of childhood SAHS.

Obstructive Sleep Apnea-Hypopnea Syndrome in Children Is Not Associated With Obesity

OBJECTIVE

The prevalence of obstructive sleep apnea-hypopnea syndrome (OSAHS) in the general pediatric population ranges from 1% to 3%. However, its prevalence in an unselected population of obese children is unknown. We studied the association between obesity and OSAHS in children diagnosed with the syndrome in a cohort of boys and girls (age range, 2-14 years) referred to the pediatric respiratory medicine outpatient clinic at our hospital for suspected apnea, snoring, or both over the past 5 years.

PATIENTS AND METHODS

The medical history of each patient was recorded and all patients underwent a physical examination, chest and nasal cavities radiography, and 8-channel respiratory polygraphy during sleep. The following variables were evaluated: sex, reason for consultation, source of referral, findings during upper airway examination, age, weight z-score (reflecting how much a finding differs from the mean and in what direction in a normally distributed sample), height z-score, body mass index (BMI) z-score, number of apneas, number of hypopneas, apnea index, hypopnea index, apnea-hypopnea index (AHI), oxygen saturation (mean and minimum) measured by pulse oximetry, number of snores, and snore index.

RESULTS

Of the 400 patients studied, 242 (60.5%) were male and 158 (39.5%) female. The mean age was 4.95 years. OSAHS (AHI> or =3) was diagnosed in 298 cases (74.5%) and these patients were then studied to determine the relation between OSAHS and obesity. The anthropometric distribution (expressed as mean [SD]) was as follows: weight z-score, 0.37 (1.31); height z-score, 0.23 (1.19); BMI, 17.063 kg/m(2) (2.51); and BMI z-score, 0.39 (1.36). The respiratory polygraph during sleep recorded an AHI of 6.56 (7.56).

CONCLUSIONS

No differences were observed between the height z-score, weight z-score, BMI z-score, age, and AHI. No association between obesity and OSAHS was found in this series. However, studies of larger, unselected populations are needed to determine if obesity is a risk factor for OSAHS in children.

[Obstructive sleep apnea-hypopnea syndrome]

We analyzed a cohort of 400 patients referred from the otorhinolaryngology department (40.05 %), primary care (PC) (36.52 %), and the pediatric pulmonary unit (17.63 %). The children were referred for clinical suspicion of apneas in 191 (47.87 %), snoring and apneas in 101 (25 %), and snoring in 87 (21.80 %). Adenotonsillar hypertrophy was found in 211 patients (52.75 %), tonsillar hypertrophy in 87 (21.75 %), and adenoid hypertrophy in 73 (18.25 %). All patients underwent respiratory polygraphy (RP) during sleep. Obstructive sleep apnea-hypopnea syndrome (OSAHS) was diagnosed in 298 patients (74.5 %). OSAHS was mild in 96 patients (24 %), moderate in 148 (37 %), and severe in 54 (13.5 %). The results of RP expressed in means plus standard deviation were as follows: number of apneas 21.38 (24.47), number of hypopneas 19.81 (20.74), apnea-hypopnea index per hour (AHI/h) 5.29 (7.10), mean oxygen saturation 94.60 (11.80), minimal saturation 83.14 (13.45), number of snores 98.27 (254.55), and snoring index per hour 5.68 (6.5). Significant differences were found between oxygen saturation and AHI/h per hour. No differences were found among age, mean oxygen saturation, area of residence, reason for consulting, and AHI/h. Adenotonsillectomy was performed in 289 patients (72.25 %) of the initial cohort. In conclusion, OSAHS in childhood is frequent. RP during sleep aids diagnosis. The main cause of OSAHS in children is adenotonsillar hypertrophy.