High-Flow Nasal Oxygen Shows Promise for Safer Surgery and Recovery

High-flow nasal cannula (HFNC) oxygen therapy represents a significant advancement in perioperative respiratory care, offering a non-invasive solution that bridges the gap between standard oxygen delivery and mechanical ventilation. This technology delivers precisely conditioned oxygen at flow rates up to 80 L/min, maintaining constant inspired oxygen concentrations while providing physiological benefits through continuous airway flushing and positive end-expiratory pressure generation.

The review synthesizes evidence from multiple randomized controlled trials demonstrating HFNC's superiority over conventional oxygen therapy across various perioperative scenarios. During procedural sedation for gastrointestinal endoscopy, HFNC reduced hypoxemia incidence from 21.2% to 2.0% in obese patients and decreased desaturation episodes by 20% even at comparable oxygen concentrations. The technology proves particularly valuable during bronchoscopy and other "shared airway" procedures where traditional ventilation methods are impractical.

A specialized application called THRIVE (transnasal humidified rapid-insufflation ventilatory exchange) extends safe apneic time during laryngoscopy and intubation, enabling tubeless pharyngeal surgery while maintaining adequate oxygenation. In postoperative care, HFNC reduces pulmonary complications, decreases reintubation rates, and facilitates smoother recovery transitions.

The physiological mechanisms underlying HFNC's effectiveness include dead space washout (improving by 1.8 mL/s per 1 L/min flow increase), PEEP generation (approximately 1.16 cmH2O per 10 L/min), and enhanced mucociliary clearance through optimal gas conditioning. These effects collectively improve ventilation-perfusion matching, reduce breathing work, and maintain alveolar recruitment.

Despite promising results, current evidence shows heterogeneity in protocols and inconsistent outcomes, particularly in high-risk populations. The technology's efficacy remains difficult to predict, potentially leading to delayed intubation decisions. Future research priorities include developing standardized protocols, creating reliable efficacy prediction models, and conducting large-scale multicenter trials to optimize clinical applications and advance perioperative respiratory management toward greater safety and effectiveness.