Pablo E. Brockmann

Myth: Gastroesophageal reflux is a pathological entity in the preterm infant

There is concern about possible consequences of gastroesophageal reflux (GER) in preterm infants. GER is perceived to be a frequent condition in these infants, often causing an exhaustive investigation and expensive therapy. We review current evidence for and against an association between GER and apnea, failure to thrive, wheezing and respiratory diseases. Although there are some limitations to the methodologies currently used for detecting GER, there is clearly a lack of unequivocal evidence supporting a causal relationship between GER and its assumed consequences, particularly in preterm infants. Despite physiologic data that stimulation of laryngeal efferents by GER may induce apnea, there is little evidence for a causal relationship between GER and apnea. Studies on preterm infants with failure to thrive have also not demonstrated an association between the latter and GER in most cases, and there is equally little evidence for a casual relationship with respiratory problems. Therefore, we believe that GER in preterm infants is only rarely associated with serious consequences and existing evidence does not support the widespread use of anti-reflux medications for treatment of these signs in this age group. An improvement of methods to identify the few preterm infants at risk for developing serious consequences of GER is urgently needed.

Influence of asthma on sleep disordered breathing in children: A systematic review

UNLABELLED The objective of this study was to perform a systematic review for the association between asthma and sleep disordered breathing (SDB) in children. We performed an electronic search in Medline, Embase, CINAHL, LILACS and Cochrane databases. Study selection criteria: children <18 y of age with diagnosis of asthma and SDB. PRIMARY OUTCOMES odds ratios (OR) and 95% confidence intervals [95%CI] of asthma for SDB were calculated. There were n = 968 citations identified, of them n = 17 studies were selected, which included n = 45 155 (53% males) children. All included studies defined asthma and SDB based on questionnaires, and only two performed a sleep study for diagnosing obstructive sleep apnea. Mean age was 8.6 ± 2.5 y. SDB was significantly more frequent in children with asthma compared with non-asthmatics: 23.9% vs 16.7% respectively, p < 0.0001. Children with asthma had a significantly higher risk for SDB: OR 1.9 [1.7; 2.2]. This systematic review showed evidence of a significant association between asthma and SDB in children. Asthma seems to be a significant risk factor for developing SDB. However, the minority of the studies based the diagnosis of SDB on polysomnography, considered the current gold standard for SDB. The physiological and temporal relationships between both conditions should be addressed in future cohort studies.

Prevalence of habitual snoring and associated neurocognitive consequences among Chilean school aged children.

OBJECTIVE To assess the prevalence of habitual snoring and symptoms of sleep disordered breathing (SDB) and their association with neurocognitive consequences in school-aged children. METHODS A population based cross-sectional study was carried out in a low income urban setting in Santiago, Chile. A parental SDB-questionnaire was adapted and applied to a community based sample of children aged 7-17 years. Hyperactive/inattentive behavior was assessed using the Conners rating scale. School grades were obtained and the associations between questionnaires results and risks for poor academic performance were investigated. RESULTS Of 700 questionnaires sent; 523 (75%) returned correctly filled in. Mean age of the subjects was 11.0±2.5 years; 246 (47%) were boys. Prevalence of habitual snoring was 18%. The Conners rating scale correlated significantly with the SDB-questionnaires score (r(s)=0.47). Children with habitual snoring showed significantly lower (mean±standard deviation) school grades in Spanish language (5.6±1.2 vs. 5.4±0.9, p-value=0.04) and general average school grades (5.9±0.6 vs. 5.7±0.6, p-value=0.05). After adjustment for possible confounding factors, children with an abnormal SDB questionnaire score had significantly higher risk for poor academic performance in Spanish language, odds ratio (95% confidence interval): 1.82 (1.01-3.27) and physical education 1.85 (1.05-3.26). DISCUSSION There was a high prevalence of habitual snoring and symptoms of SDB in this survey of Chilean children, being among the highest reported. The presence of habitual snoring and an abnormal SDB questionnaire were associated with poor academic performance and hyperactive behavior.

Reference values for pulse oximetry recordings in healthy term neonates during their first 5 days of life

Objective To determine reference values for pulse oximeter saturation (SpO2) variables and desaturation event indices in healthy term neonates during their first 5 days of life, and to compare two definitions for the identification of desaturation events. Design Observational study (case series). Setting Maternity ward, Department of Neonatology, University Childrens Hospital, Tuebingen, Germany. Patients 209 healthy term neonates (50% boys), median (minimum–maximum) age 2 (0–5) days. Main outcome measures SpO2 variables (eg, median SpO2) and desaturation events obtained by motion-resistant pulse oximetry (VitaGuard 310; Getemed, incorporating Masimo SET). Desaturation events were identified based either on a good signal quality (SIQ) provided by the device or on the combination of a good SIQ and an undisturbed pulse waveform (SIQ+PW). Desaturation event indices were calculated as desaturation events divided by hour of artefact-free recording time. Results The mean (SD) of the obtained median SpO2 was 97.3% (1.4%). There were 36 (17%) subjects with desaturation events to <80% SpO2 based on SIQ, and 26 (12%) based on SIQ+PW. Median desaturation event rate to <80% SpO2/h (75th centile; 95th centile; maximum) was 0 (0; 0.6; 2.3) based on SIQ, and 0 (0; 0.4; 1.7) based on SIQ+PW. Conclusions Desaturation events to <80% SpO2 were rare in our sample of healthy term neonates during their first 5 days of life. Analysis of SIQ alone could be a quick and simple alternative to traditional analysis of PW. The presented reference values may be used for clinical decision making.

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.

Sleep-disordered breathing in children with asthma: a systematic review on the impact of treatment

Background The objective was to perform a systematic review in order to describe the relationship between asthma and sleep-disordered breathing (SDB) in children, especially regarding the impact of treatment and management. Methods We performed an electronic search in MEDLINE, EMBASE, and LILACS database. Study inclusion criteria were the following: 1) studies that examined the relationship between asthma/wheezing and SDB/obstructive sleep apnea (OSA); and 2) studies conducted in children <18 years of age. Primary outcomes were the prevalence of asthma and SDB, the tests used for diagnosis, and the influence of their treatment and management. Results One thousand and twenty studies were identified, among which 32 were selected (n=143,343 children; 51% males; age [mean ± standard deviation] 8.4±2.5 years). Most studies (n=26) diagnosed SDB using questionnaires or clinical history. Nine studies performed a sleep study for diagnosing OSA. The diagnosis of asthma was based on clinical history (n=16), previous medical diagnosis (n=4), questionnaires (n=12), and spirometry (n=5). Children with asthma were more likely to develop habitual snoring and OSA, and children with SDB were more likely to develop asthma. Moreover, asthma was associated with more severe OSA, and the presence of SDB was associated with severe asthma. Treatment of SDB with adenotonsillectomy was associated with significant asthma improvement. Conclusion The relationship between asthma and SDB appears to be bidirectional, and adenotonsillectomy appears to improve asthma control. Future trials on how asthma treatment could impact on SDB are needed.

Elevated IL-3 and IL-12p40 levels in the lower airway of infants with RSV-induced bronchiolitis correlate with recurrent wheezing.

Respiratory Syncytial Virus (RSV) is the first cause of hospitalization due to bronchiolitis in infants. RSV bronchiolitis has been linked to asthma and recurrent wheezing, however the mechanisms behind this association have not been elucidated. Here, we evaluated the cytokine and chemokine profiles in the airways in infants with RSV bronchiolitis. Nasopharyngeal Aspirates (NPA) and Bronchoalveolar Lavage Fluids (BALF) from infants hospitalized due to RSV bronchiolitis and healthy controls were analyzed for cytokine and chemokine production. We observed elevated levels of Th2 cytokines (IL-3, IL-4, IL-10 and IL-13), pro-inflammatory cytokines and chemokines (IL-1β, IL-6, TNF-β, MCP-1/CCL2, MIP-1α/CCL3 and IL-8/CXCL8) in BALF from infants with RSV bronchiolitis, as compared to controls. We found a direct correlation of IL-3 and IL-12p40 levels with the development of recurrent wheezing later in life. These results suggest that IL-3 and IL-12p40 could be considered as molecular predictors for recurrent wheezing due to RSV infection.

Treatment of Obstructive Sleep Apnea in Infants with Trisomy 21 Using Oral Appliances

Objective To perform a retrospective study to evaluate the effect of oral appliances, aimed at increasing the pharyngeal space, on obstructive sleep apnea (OSA) in infants with trisomy 21 (TS21). Design and Setting Retrospective study in a tertiary referral center. Intervention We analyzed data from 51 consecutive infants (mean age, 2.7 months) who underwent polysomnography (PSG) and were offered our treatment concept. Primary study variable was the mixed-obstructive apnea index (MOAI); OSA was defined as a MOAI ≥ 1. Results Twenty-seven infants (53%) had OSA. Their median MOAI improved from 2.3 (1 to 13) to 0 (0 to 0.2; P < .05). Seven of these infants were treated with an appliance that included some type of velar extension to move the tongue base forward. Of the 24 infants without OSA at admission, follow-up PSG results were available for 13. Three infants from this group had developed OSA by the time of a repeat PSG. Conclusion In patients with TS21, OSA may already develop in infancy. Early treatment may improve OSA. Oral appliances with some type of velar extension may be considered as an alternative to other treatment procedures.

Sleep-Disordered Breathing in Adolescents and Younger Adults: A Representative Population-Based Survey in Chile

BACKGROUND Prevalence and potential risk contributors of sleep-disordered breathing (SDB) in adolescents and younger adults remain unclear. We hypothesized that SDB prevalence in younger Hispanic adults is higher than the limited evidence indicates. METHODS This is a population-based study of Hispanic subjects surveyed as part of the Chilean National Health Survey database. For this study, only subjects aged 15 to 40 years were included. Sleep and demographic questionnaires were used to assess SDB prevalence and its risk factors. Anthropometric measurements were performed in each subject. Prevalence was calculated for each SDB-related symptom. A regression model was constructed to investigate demographic risk factors of SDB. RESULTS A total of 2,147 subjects were included. Mean age (± SD) was 27.2 ± 7.2 years, n = 899 (42%) were men. Habitual snoring was highly prevalent, with an average of 53.8% in men and 38.3% in women. Snoring, witnessed apneas, and daytime somnolence increased continuously with age, with an abnormal SDB questionnaire score detected in 2.5%. Reported sleep duration was 7.61 ± 1.67 hours during weekdays and 8.27 ± 2.11 hours during weekends. Snoring frequency was significantly higher in men than women at nearly all age groups, and an adjusted regression model (OR [95% CI]) identified male sex (2 [1.6-2.5]; P < .001) and BMI (1.08 [1.03-1.12]; P < .001) as independent risk factors for snoring. CONCLUSION The risk of SDB is highly prevalent in younger adults, even in females, and increases with age and BMI. The high prevalence and low awareness justify active screening and treatment of SDB in this population.

Diagnostic accuracy of the Spanish version of the Pediatric Sleep Questionnaire for screening of obstructive sleep apnea in habitually snoring children

OBJECTIVES We aimed to determine the diagnostic test accuracy of the Spanish version of the respiratory symptoms scale of the Pediatric Sleep Questionnaire (PSQ) in habitually snoring children for identifying obstructive sleep apnea (OSA). METHODS Habitually snoring children referred for polysomnography (PSG) were recruited. Parents answered the PSQ prior to PSG. Based on an apnea-hypopnea index (AHI) >1.0 in PSG, children were divided into OSA and primary snorers. Correlations to PSG indices and diagnostic test accuracy measures were calculated. RESULTS Of the 83 (n = 53 males, mean age 9.5 ± 3.6 years) habitually snoring children included, 35 had OSA. The previously validated PSQ cutoff value of 0.33 showed a specificity of 0.72 and sensitivity of 0.78. The PSQ score correlated significantly with the AHI rs = 0.313 (p-value = 0.004). Six items of the PSQ were significantly different between cases and controls. A subscale constructed on these six PSQ items concerning respiratory symptoms showed a good sensitivity (0.886) and an excellent negative likelihood ratio (0.261). PSQ was able to identify 89% of the children with OSA correctly. CONCLUSIONS This version of the PSQ was able to identify children with OSA, separating them from those with primary snoring. The use of this simple, standardized questionnaire tool seems to be helpful and may improve clinical decision making in habitually snoring children.