Respiratory Support in Pediatric Critical and Near-Fatal Asthma: A Narrative Review

Pediatric asthma remains a leading cause of emergency department visits and hospitalizations worldwide. Patients with critical asthma represents a subset of patients requiring respiratory support beyond standard pharmacologic therapy. Management of respiratory support in these patients has evolved dramatically, with intubation rates decreasing from 6.9% to 3.4% between 2009 and 2019 while noninvasive ventilation use doubled and high-flow nasal cannula utilization increased from 11% to 52%. This narrative review examines current evidence and practical considerations for respiratory support strategies across the spectrum of pediatric critical asthma care. The pathophysiology of critical asthma creates unique challenges fundamentally different from other causes of respiratory failure. Dynamic hyperinflation from progressive air trapping and intrinsic positive end-expiratory pressure (PEEP) development represents the cornerstone derangement, requiring ventilation strategies that seems divergent from those utilized in acute respiratory distress syndrome. High-flow nasal cannula provides benefit primarily through dead space washout and gas conditioning, while noninvasive ventilation offers comprehensive support by augmenting ventilation and offsetting intrinsic PEEP effects. When mechanical ventilation becomes necessary, controlled hypoventilation with acceptance of hypercapnia while maintaining pH > 7.20 has dramatically reduced mortality compared with historical approaches targeting normocapnia. Pressure-controlled ventilation may offer physiologic advantages over volume-controlled modes by providing more uniform gas distribution in airways with varying degrees of obstruction. A structured three-phase ventilation approach emphasizes initial hyperinflation clearance, followed by acidosis resolution, then careful weaning with attention to dynamic hyperinflation monitoring. Current survival rates exceed 96% for children reaching medical care, representing substantial improvement from historical mortality rates of 20-30%. Optimal respiratory support in critical asthma requires understanding that mechanical ventilation strategies in asthma differs from other respiratory failure etiologies, with dynamic hyperinflation management taking precedence over traditional lung-protective strategies. Future research priorities include developing severity prediction tools, optimizing noninvasive protocols, and investigating personalized approaches on the basis of emerging understanding of asthma phenotypes and endotypes.