Athanasios G. Kaditis

Adenotonsillectomy outcomes in treatment of obstructive sleep apnea in children: a multicenter retrospective study.

RATIONALE The overall efficacy of adenotonsillectomy (AT) in treatment of obstructive sleep apnea syndrome (OSAS) in children is unknown. Although success rates are likely lower than previously estimated, factors that promote incomplete resolution of OSAS after AT remain undefined. OBJECTIVES To quantify the effect of demographic and clinical confounders known to impact the success of AT in treating OSAS. METHODS A multicenter collaborative retrospective review of all nocturnal polysomnograms performed both preoperatively and postoperatively on otherwise healthy children undergoing AT for the diagnosis of OSAS was conducted at six pediatric sleep centers in the United States and two in Europe. Multivariate generalized linear modeling was used to assess contributions of specific demographic factors on the post-AT obstructive apnea-hypopnea index (AHI). MEASUREMENTS AND MAIN RESULTS Data from 578 children (mean age, 6.9 +/- 3.8 yr) were analyzed, of which approximately 50% of included children were obese. AT resulted in a significant AHI reduction from 18.2 +/- 21.4 to 4.1 +/- 6.4/hour total sleep time (P < 0.001). Of the 578 children, only 157 (27.2%) had complete resolution of OSAS (i.e., post-AT AHI <1/h total sleep time). Age and body mass index z-score emerged as the two principal factors contributing to post-AT AHI (P < 0.001), with modest contributions by the presence of asthma and magnitude of pre-AT AHI (P < 0.05) among nonobese children. CONCLUSIONS AT leads to significant improvements in indices of sleep-disordered breathing in children. However, residual disease is present in a large proportion of children after AT, particularly among older (>7 yr) or obese children. In addition, the presence of severe OSAS in nonobese children or of chronic asthma warrants post-AT nocturnal polysomnography, in view of the higher risk for residual OSAS.

Obstructive sleep disordered breathing in 2- to 18-year-old children: Diagnosis and management

This document summarises the conclusions of a European Respiratory Society Task Force on the diagnosis and management of obstructive sleep disordered breathing (SDB) in childhood and refers to children aged 2–18 years. Prospective cohort studies describing the natural history of SDB or randomised, double-blind, placebo-controlled trials regarding its management are scarce. Selected evidence (362 articles) can be consolidated into seven management steps. SDB is suspected when symptoms or abnormalities related to upper airway obstruction are present (step 1). Central nervous or cardiovascular system morbidity, growth failure or enuresis and predictors of SDB persistence in the long-term are recognised (steps 2 and 3), and SDB severity is determined objectively preferably using polysomnography (step 4). Children with an apnoea–hypopnoea index (AHI) >5 episodes·h−1, those with an AHI of 1–5 episodes·h−1 and the presence of morbidity or factors predicting SDB persistence, and children with complex conditions (e.g. Down syndrome and Prader–Willi syndrome) all appear to benefit from treatment (step 5). Treatment interventions are usually implemented in a stepwise fashion addressing all abnormalities that predispose to SDB (step 6) with re-evaluation after each intervention to detect residual disease and to determine the need for additional treatment (step 7). Management of obstructive sleep disordered breathing in childhood should follow a stepwise approach http://ow.ly/SdKwD

Algorithm for the diagnosis and treatment of pediatric OSA: A proposal of two pediatric sleep centers

There is currently no consensus on the best method of managing of obstructive sleep apnea (OSA) in childhood. In the present paper, an algorithm for the diagnosis and treatment of the disorder is proposed. Sleep apnea is suspected when parents report relevant symptoms or when there are abnormalities that predispose to OSA such as adenotonsillar hypertrophy, obesity, craniofacial anomalies, or neuromuscular disorders. OSA-associated morbidity including elevated blood pressure, daytime sleepiness or learning problems, growth failure, and enuresis should be recognized. Severity of intermittent upper airway obstruction during sleep can be determined objectively by polysomnography or, if polysomnography is not available, by nocturnal pulse oximetry. Risk factors predicting persistence of OSA in adolescence (male gender, development of obesity) need to be identified. Children with moderate-to-severe OSA, or with mild OSA, but accompanied by morbidity, or by risk factors predicting persistence of the disorder should have priority for treatment. An individualized and multifaceted therapeutic approach which addresses in a step-by-step fashion all abnormalities that contribute to upper airway obstruction during sleep is necessary.

Urine levels of catecholamines in Greek children with obstructive sleep-disordered breathing†

Adults with obstructive sleep apnea have increased sympathetic activity. It was hypothesized that in children with symptoms of obstructive sleep‐disordered breathing (SDB), morning urine levels of catecholamines correlate with severity of nocturnal hypoxemia.

Absence of blood pressure, metabolic, and inflammatory marker changes after adenotonsillectomy for sleep apnea in Greek children.

Pediatric studies revealed associations of obstructive sleep‐disordered breathing (SDB) with inflammation, metabolic dysfunction, and elevated blood pressure. Evidence about effects of adenotonsillectomy on these abnormalities is scarce. Aim of this investigation was to assess changes in C‐reactive protein (CRP), circulating intercellular adhesion molecule‐1 (cICAM‐1), insulin and blood pressure levels after adenotonsillectomy for SDB in Greek children.

Urine Concentrations of Cysteinyl Leukotrienes in Children With Obstructive Sleep-Disordered Breathing

BACKGROUND Adenotonsillar tissue of children with obstructive sleep-disordered breathing (SDB) has increased content of cysteinyl leukotrienes (CysLTs) and expression of CysLTs receptors. Furthermore, CysLTs concentrations in the nasal exhaled breath condensate of children with sleep apnea are elevated. OBJECTIVE To investigate the relationship between urine levels of CysLTs and severity of SDB in children. METHODS Morning urine concentrations of CysLTs were measured in children with symptoms of SDB and in control subjects with recurrent tonsillitis and without snoring who underwent polysomnography and were expressed in pg/mL per mg/dL of urine creatinine. RESULTS Nineteen children with moderate-to-severe SDB (mean [+/- SD] age, 5.4 +/- 1.6 years; obstructive apnea-hypopnea index [OAHI]: 14.4 +/- 9.6 episodes/h), 29 subjects with mild SDB (5.1 +/- 1.5 years; OAHI: 2.9 +/- 0.8 episodes/h), 26 children with primary snoring (PS) [7 +/- 2.6 years; OAHI: 1.1 +/- 0.3 episodes/h], and 18 control subjects (6.4 +/- 2.5 years; OAHI: 0.7 +/- 0.3 episodes/h) were studied. Children with moderate-to severe SDB had higher log-transformed urine CysLTs levels than those with mild SDB, PS, or control subjects (2.39 +/- 0.51 vs 2.06 +/- 0.26 vs 2.11 +/- 0.25 vs 1.86 +/- 0.28; p < 0.05). Log-transformed CysLTs concentration, tonsillar size, and body mass index z score were significant predictors of log-transformed OAHI (p < 0.01). CONCLUSIONS Urine excretion of CysLTs is related to SDB severity in children. This finding indicates that 5-lipoxygenase pathway products participate in the pathogenesis of obstructive sleep apnea in childhood or alternatively that SDB promotes CysLTs biosynthesis.

Cysteinyl Leukotriene Receptors Are Expressed by Tonsillar T Cells of Children With Obstructive Sleep Apnea

BACKGROUND Increased expression of cysteinyl leukotriene receptors (cysteinyl leukotriene receptor-1 [LT1-R]; cysteinyl leukotriene receptor-2 [LT2-R]) has been detected in adenotonsillar tissue from children with sleep-disordered breathing (SDB) compared to control subjects. LT1-R has been localized in myeloperoxidase-positive cells. This phenomenon possibly contributes to lymphoid tissue enlargement and may be related to systemic inflammation. OBJECTIVE To characterize cells expressing LT1-R and LT2-R in tonsillar tissue and assess serum C-reactive protein (CRP) levels in children with and without SDB. METHODS Immunohistochemistry with LT1-R and LT2-R antibodies was used to examine tonsils from children who had tonsillectomy (with or without adenoidectomy) for SDB and from control subjects operated for recurrent tonsillitis/otitis. All participants underwent preoperative polysomnography and measurement of morning serum CRP. RESULTS Fifteen children with SDB (mean age +/- SD, 6.4 +/- 2.1 years; apnea-hypopnea index, 9.6 +/- 5.6 episodes per hour) and 11 control subjects (age, 7.5 +/- 2.8 years; apnea-hypopnea index, 7 +/- 0.3/h) were examined. Immunoreactivity for LT1-R and LT2-R was detected in tonsillar extrafollicular areas of all subjects with SDB but not of control subjects. Cells expressing leukotriene receptors were CD3+ lymphocytes. Children with SDB and control subjects were similar regarding CRP levels: 0.11 +/- 0.15 mg/dL vs 0.09 +/- 0.15 mg/dL, respectively (p > 0.05). CONCLUSIONS Tonsils of children with SDB but not of control subjects have enhanced expression of cysteinyl leukotriene receptors in T lymphocytes without an associated increase in serum CRP concentration. Up-regulation of LT1-R and LT2-R could potentially promote tonsillar enlargement in children with obstructive sleep apnea.

Early gastrostomy reduces the rate of ventilator-associated pneumonia in stroke or head injury patients.

Presence of a nasogastric tube is a risk factor for the development of ventilator-associated pneumonia (VAP). Alternatively, gastrostomy can be used for administration of enteral feedings. To determine whether early performance of gastrostomy affects frequency of VAP, a randomised, controlled study was carried out in patients mechanically ventilated for stroke or head injury. In the gastrostomy group, patients underwent the procedure within 24 h of intubation. A nasogastric tube was inserted in controls. Individual subjects were studied for 3 weeks. In total, 20 subjects (mean age 48±15.2 yrs) were allocated to the gastrostomy group, and 21 to the control group (46.6±15.4 yrs). Of these groups, two (10%) and eight (38.1%) developed VAP, respectively. Four patients with gastrostomy and three controls did not complete the study (due to weaning from ventilatory support or death). After excluding these subjects, difference in VAP frequency persisted: two out of 16 subjects with gastrostomy had VAP (12.5%) versus eight out of 18 controls (44.4%). There were no differences in duration of hospitalisation or mortality between the two groups. In conclusion, in patients mechanically ventilated for stroke or head injury early gastrostomy is associated with a lower frequency of ventilator-associated pneumonia compared with a nasogastric tube.

Obesity and Persisting Sleep Apnea After Adenotonsillectomy in Greek Children

BACKGROUND The relative importance of obesity and adenotonsillar hypertrophy in the pathogenesis of obstructive sleep-disordered breathing (SDB) in childhood is unclear. Adenotonsillectomy (AT) for SDB is not always curative, and obese children are at increased risk for residual disease postoperatively. OBJECTIVE The aim of this investigation was to assess the efficacy of AT as treatment for SDB in obese and nonobese children. METHODS Children with adenoidal and/or tonsillar hypertrophy who underwent AT for the treatment of SDB underwent polysomnography preoperatively and postoperatively. A body mass index (BMI) z score of > 1.645 was used to define obesity. The achievement of a postoperative obstructive apnea-hypopnea index (OAHI) of less than one episode per hour (ie, the cure of SDB) was the primary outcome measure. RESULTS Twenty-two obese children (mean [+/- SD] age, 5.8 +/- 1.8 years; mean BMI z score, 2.6 +/- 0.8; mean OAHI, 9.5 +/- 9.7 episodes per hour) and 48 nonobese children (mean age, 6.9 +/- 2.6 years; mean BMI z score, 0.09 +/- 1.1; OAHI, 6 +/- 5.4 episodes per hour) were recruited. After surgery, obese and nonobese subjects did not differ in the efficacy of AT (postoperative OAHI of less than one episode per hour, 22.7% vs 25% of subjects, respectively; p > 0.05). The presence of obesity, adenoidal or tonsillar hypertrophy, gender, and postoperative BMI change were not significant predictors of SDB cure. CONCLUSIONS Obesity does not necessarily predict an unfavorable outcome of AT as treatment for SDB.

Pediatric OSAS: Oximetry can provide answers when polysomnography is not available

Overnight polysomnography is the gold standard tool for the diagnosis of obstructive sleep apnea syndrome (OSAS) in habitually snoring children, but it is expensive and not always available. Nocturnal oximetry has been proposed as an abbreviated and low-cost testing modality for the diagnosis of OSAS. In this systematic review, 25 original articles were evaluated to: (i) summarize reference values of nocturnal oximetry parameters in healthy children; (ii) identify abnormal oximetry patterns that predict OSAS in habitually snoring children; (iii) delineate abnormalities in oximetry that can predict responses to treatment interventions for OSAS and potential complications. Nocturnal SpO2 drops <90%, more than two clusters of desaturation events (≥4%) and oxyhemoglobin desaturation (≥4%) index (ODI4) >2.2 episodes/h are unusual in children without OSAS. At least three clusters of desaturation events, and at least three SpO2 drops below 90% in a nocturnal oximetry recording are indicative of moderate-to-severe OSAS. An ODI4 >2 episodes/h combined with OSAS symptoms also exhibits high positive predictive value for apnea-hypopnea index >1 episode/h. Children without clusters of desaturation events have low risk of major respiratory complications following adenotonsillectomy. Thus, nocturnal oximetry emerges as a valuable tool that can facilitate treatment decisions when polysomnography is not available.