Abstract
INTRODUCTION: Acute respiratory distress syndrome (ARDS) manifests as acute pulmonary inflammation associated with high mortality. While intermittent prone positioning for 12-16 h is an essential intervention in managing severe ARDS, clinical challenges arise when patients exhibit immediate physiological deterioration during supine transitions. Also, the clinical utility of monitoring mechanical power (MP) as a surrogate for lung-protective ventilation during prone ventilation remains unclear. CASE PRESENTATION: We report a 55-years-old female patient with influenza A-associated severe ARDS. Despite an initial trial of high-flow nasal cannula (HFNC) therapy, the patient was intubated and initiated on invasive mechanical ventilation for refractory hypoxemia. Conventional 16-h prone positioning cycles were complicated by marked desaturation and MP instability upon transition to the supine position. We implemented a novel strategy of continuous ultra-prolonged prone positioning sustained for 5 consecutive days. The intervention resulted in a gradual improvement in oxygenation and was uniquely accompanied by a steady decline in MP from 18.14 to 12.33 J/min. Stabilization of both oxygenation and ventilatory mechanics subsequently allowed a safe return to the supine position, followed by successful ventilator weaning and extubation. CONCLUSION: Ultra-prolonged prone represented a potentially effective salvage strategy for the severe ARDS patient who was intolerant to standard intermittent cycles. Furthermore, longitudinal monitoring of MP may provide crucial physiological guidance, enabling a more individualized and lung-protective approach during prone ventilation.