Diaphragm atrophy is present in children on mechanical ventilation for acute respiratory failure. Diaphragm contractility, measured as thickening fraction, is strongly correlated with spontaneous breathing fraction. The combination of exposure to neuromuscular blockade infusion with low overall spontaneous breathing fraction is associated with a greater degree of atrophy.

Objectives: Diaphragm atrophy is evident during invasive ventilation for pediatric acute respiratory failure, but with unknown significance. We hypothesized that diaphragm atrophy in pediatric acute respiratory failure is associated with prolonged noninvasive positive pressure ventilation following extubation. Design: Prospective observational study. Setting: Single-center academic PICU. Patients: Invasively ventilated children with acute respiratory failure. Interventions: Diaphragm ultrasound was performed within 36 hours after intubation and repeated within 48 hours preceding extubation. Rapid shallow breathing index at 15 and 30 minutes of a spontaneous breathing trial and negative inspiratory force were collected in a subset of patients concurrently with the ultrasound measurements. Measurements and Main Results: Diaphragm thickness at end-expiration was measured to assess for diaphragm atrophy during mechanical ventilation. Percentage change in diaphragm thickness at end-expiration was defined as baseline diaphragm thickness at end-expiration minus final, preextubation diaphragm thickness at end-expiration divided by baseline diaphragm thickness at end-expiration. The primary outcome measure was duration of noninvasive positive pressure ventilation following extubation with prolonged use defined as noninvasive positive pressure ventilation use for greater than 24 hours postextubation. Among 56 children, 47 (median age, 15.5 mo; interquartile range, 6–53 mo) had diaphragm thickness at end-expiration measured within 48 hours prior to extubation. Fourteen (30%) had prolonged noninvasive positive pressure ventilation use with median duration 110 hours (interquartile range, 52–130 hr). The median percentage change of diaphragm thickness at end-expiration from baseline among those with and without prolonged noninvasive positive pressure ventilation use was –20% (interquartile range, –32% to –10%) versus –7% (interquartile range, –21% to 0%) (p = 0.04). Conclusions: Diaphragm atrophy is associated with prolonged postextubation noninvasive positive pressure ventilation in children with acute respiratory failure. Serial bedside diaphragm ultrasound may identify children at risk for prolonged noninvasive positive pressure ventilation use after extubation.

Point-of-care ultrasound is currently widely used across the landscape of pediatric care. Ultrasound machines are now smaller, are easier to use, and have much improved image quality. They have become common in emergency departments, ICUs, inpatient wards, and outpatient clinics. Recent growth of supportive evidence makes a strong case for using point-of-care ultrasound for pediatric interventions such as vascular access (in particular, central-line placement), lumbar puncture, fluid drainage (paracentesis, thoracentesis, pericardiocentesis), suprapubic aspiration, and soft tissue incision and drainage. Our review of this evidence reveals that point-of-care ultrasound has become a powerful tool for improving procedural success and patient safety. Pediatric patients and clinicians performing procedures stand to benefit greatly from point-of-care ultrasound, because seeing is believing.