Follow-up of primary snoring in children.

We reevaluated 13 children with primary snoring 3 years after their original polysomnograms were performed and compared them with healthy control subjects. As a group, the patients' snoring and polysomnographic findings did not change. There was no difference in any sleep-disordered breathing of the patients and control subjects. Only the youngest individual in the study developed frank obstructive sleep apnea. Children with primary snoring are not likely to develop polysomnography-confirmed obstructive sleep apnea, and it is safe to defer treatment.

Adenoid size is related to severity but not the number of episodes of obstructive apnea in children.

OBJECTIVE: The objective of this study was to determine the extent to which adenotonsillar hypertrophy contributes to the severity of obstructive sleep apnea (OSA) in children. STUDY DESIGN: Thirty-three consecutive children who were referred to a sleep disorders center for evaluation of suspected OSA had standard lateral neck roentgenography performed. Adenoid size was determined by measuring the adenoidal-nasopharyngeal (AN) ratio. Tonsil size was quantitated on physical examination. The severity of OSA was determined by full-night polysomnography in the sleep laboratory. RESULTS: All of the patients reported snoring with trouble breathing, apneas, or both problems witnessed by a parent. The patients' respiratory disturbance index ranged from 0 to 95.3 (mean +/- SD 12.5 +/- 9.1). The patients' AN ratio ranged from 0.48 to 0.98 (0.76 +/- 0.14); 30 (91%) of the 33 patients had AN ratios greater than published normal means, and 16 (48%) had AN ratios more than 2 standard deviations above published means. Although the AN ratio and tonsil size did not predict the number of apneas, a significant relationship was seen between the AN ratio and the duration of obstructive apneas (r = 0.48, p < 0.01). Obesity (percent ideal body weight) was the only independent predictor for the number of respiratory events per hour of sleep (r = 0.49, p < 0.01). Percent ideal body weight was also the major predictor of the lowest oxyhemoglobin saturation (r = -0.58, p < 0.0001), but the AN ratio also contributed to the variance in saturation, with a correlation coefficient (r) of 0.69 for the two factors (p < 0.0001). CONCLUSION: Lymphoid hyperplasia affects the severity of apnea more than the number of obstructive apneas. The pathophysiologic characteristics of OSA in children probably involve complex interactions between pharyngeal size and mechanics.

Vulnerability of respiratory control in healthy preterm infants placed supine.

OBJECTIVE: We tested the hypothesis that healthy preterm infants have attenuated ventilatory responses to hypercapnia, associated with a decreased rib cage contribution to ventilation, in the supine versus prone position. STUDY DESIGN: We elicited hypercapnic ventilatory responses from 19 healthy preterm infants (postconceptional age 35 +/- 1 weeks) who were being prepared for hospital discharge. The O2 saturation was continuously monitored. Before and during CO2 rebreathing, ventilation was measured with a nasal mask pneumotachygraph and was derived from chest wall motion as determined by respiratory inductance plethysmograph. This measuring method allowed us to compare both ventilation and the percentage rib cage contribution to ventilation between supine and prone positions. Statistical analysis employed analysis of variance with repeated measures. RESULTS: The supine position was associated with a higher respiratory rate (p < 0.02) and lower O2 saturation (p < 0.007) than the prone position. The increase in ventilation in response to hypercapnia was lower in the supine than in the prone position. This was statistically significant for the respiratory inductance plethysmograph (p < 0.008) but not the pneumotachygraph (p = 0.077), and was associated with a smaller rib cage contribution to ventilation in the supine than in the prone position (p < 0.0001). CONCLUSION: Respiratory control may be vulnerable when healthy preterm infants are placed supine. Widespread avoidance of the prone position may not be appropriate for such patients.

Use of nasal continuous positive airway pressure as treatment of childhood obstructive sleep apnea.

OBJECTIVE: To determine the safety and efficacy of nasal continuous positive airway pressure (CPAP) for obstructive sleep apnea (OSA) during childhood and the effects of growth and maturation on CPAP requirements. DESIGN: Retrospective study with use of a written questionnaire administered to pediatric practitioners treating sleep disorders. SETTING: Nine academic pediatric sleep disorders centers. RESULTS: Data were obtained for 94 patients. Three percent of patients receiving CPAP were less than 1 year, 29% were 1 to 5 years, 36% were 6 to 12 years, and 32% were 13 to 19 years of age; 64% were boys. The longest duration of CPAP use was 4 years. Indications for CPAP included OSA associated with obesity (27%), craniofacial anomalies (25%), idiopathic OSA persisting after adenoidectomy and tonsillectomy (17%), and trisomy 21 (13%). Continuous positive airway pressure was effective in 81 patients (86%), in one patient it was unsuccessful, and in 12 patients compliance was inadequate. The median pressure required was 8 cm H2O (range, 4 to 20 cm H2O); pressure requirements were independent of age or diagnosis. Twenty-two percent of patients eventually required a modification of CPAP levels. Complications of CPAP were minor. Sixty-four percent of centers reported difficulty in obtaining funding for CPAP. CONCLUSIONS: Continuous positive airway pressure is safe, effective, and well tolerated by children and adolescents with OSA. Experience in infants is limited. As pressure requirements change with patient growth, we recommend that CPAP requirements be regularly reevaluated over time. The marked center-to-center variability in CPAP use suggests that specific indications for this therapy require clarification.

A prospective randomized double-blind study to evaluate the effect of dexamethasone in acute laryngotracheitis.

To determine whether a single dose of dexamethasone (0.6 mg/kg) is useful in the treatment of acute laryngotracheitis (croup), 29 hospitalized patients with acute laryngotracheitis were randomly assigned in a double-blind fashion to receive either parenterally administered dexamethasone (n = 16) or a saline placebo (n = 13). Severity of the illness was assessed by a clinical croup score based on retractions, stridor, air entry, cyanosis, and level of consciousness. Twelve hours from the time of injection, the patients receiving the dexamethasone had a statistically significant decline in median croup score from 4.5 to 1.0 (p less than 0.001), whereas the patients receiving the placebo did not. By 24 hours, a decline of two or more points in the total croup score was noted in 85% of the patients in the dexamethasone group compared with 33% of the patients in the placebo group (p = 0.027). During this same period, only 19% of patients receiving dexamethasone required two or more racemic epinephrine treatments in comparison with 62% of patients who received the placebo (p less than 0.05). There was no statistical difference between the two groups in improvement in oxygen saturation, respiratory rates, or duration of hospitalization. We conclude that dexamethasone is beneficial in reducing the overall severity of moderate to severe acute laryngotracheitis during the first 24 hours after injection.