Salbutamol Worsens the Autonomic Nervous System Dysfunction of Children With Sickle Cell Disease.

Background: Sickle cell disease (SCD) patients with asthma have an increased rate of vaso-occlusive crisis (VOC) and acute chest syndrome (ACS) episodes when compared to those without asthma. We hypothesized that either asthma diagnosis or bronchodilator treatment might aggravate SCD via their modulating effect on the autonomic nervous system (ANS).

Methods: Cross-sectional evaluation of heart rate variability (HRV) during pulmonary function tests, including salbutamol administration, in children with SCD receiving asthma treatment or not when compared to asthmatic children without SCD matched for ethnicity.

Cross-sectional study of loop gain abnormalities in childhood obstructive sleep apnea syndrome.

Study Objectives: We aimed to assess ventilatory control in typically developing children with and without obstructive sleep apnea (OSA).

Methods: Otherwise healthy children referred for suspicion of OSA were recruited. In addition to polysomnography, we analyzed loop, controller and plant gains (ie, LG, CG, and PG), which reflect the stability of control, chemoreceptor sensitivity and the pulmonary control of blood gases in response to changes in ventilation, respectively, from tidal breathing recordings during wakefulness.

Cross-sectional phenotyping of small airway dysfunction in preschool asthma using the impulse oscillometry system.

Asthma is a chronic inflammatory airway disorder known to induce small airways dysfunction (SAD). It is important to develop tools to assess the presence and extent of SAD in daily clinical practice. An Impulse Oscillometry System (IOS) might detect SAD, but the validity of the underlying model (serial Resistive airway and Compliant tissue model: RC model) in diseased lungs remains questionable.

The utility of acoustic pharyngometry and rhinometry in pediatric obstructive sleep apnea syndrome.

Objective: Our objective was to evaluate the usefulness of acoustic pharyngometry and rhinometry in assessing obstructive sleep apnea (OSA) syndrome in children.

Patients/methods: Patients who were hospitalized for polysomnography underwent acoustic pharyngometry and rhinometry in sitting and supine positions to measure anatomical (pharyngeal and nasopharyngeal) volumes and collapsibility characteristics (reduction of pharyngeal volume, estimated pharyngeal compliance, and reduction of nasopharyngeal volume).

Results: In this study, we prospectively enrolled 103 children (median age, 10.

Pulse wave amplitude reduction as a surrogate for cortical arousal during sleep hypopnea in children.

Objectives: The accuracy of respiratory polygraphy (RP) is limited because of the absence of electroencephalography (EEG). Pulse wave amplitude (PWA) reduction has been shown to be a marker of autonomic activation during arousal, and may represent a substitute for obstructive respiratory-related cortical arousal (RRCA). This study tested the hypothesis that PWA could be a surrogate for RRCA in detecting obstructive hypopnea (OH) in a pediatric population.