HEMODYNAMIC TOLERANCE OF SHORT-DURATION PRONE VENTILATION IN MECHANICALLY VENTILATED ARDS PATIENTS

Abstract

Background: Acute Respiratory Distress Syndrome is a critical pulmonary condition characterized by severe hypoxemia and impaired respiratory mechanics requiring intensive ventilatory support. Prone positioning has gained importance as an adjunctive intervention in ARDS because of its beneficial effects on pulmonary recruitment and ventilation–perfusion matching. While its role in improving oxygenation is well recognized, information regarding the cardiovascular response to short-duration prone ventilation remains limited. Aim: To assess the hemodynamic alterations occurring during 8-hour prone ventilation in mechanically ventilated patients with ARDS. Methodology: This prospective observational study was conducted among 95 invasively ventilated ARDS patients admitted to the Intensive Care Unit of a tertiary care hospital. Patients fulfilling the Berlin criteria for ARDS were recruited consecutively during the study period. Baseline hemodynamic variables and oxygenation parameters were recorded in the supine position prior to prone positioning. Patients were subsequently maintained in the prone position for eight hours under continuous monitoring and standard ICU care. Pulse rate, systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) were assessed at predefined intervals during proning and after repositioning to supine. Oxygen saturation and arterial oxygenation parameters were also evaluated. Statistical analysis was performed using paired t-test, and a p value <0.05 was considered statistically significant. Results: Eight-hour prone ventilation resulted in significant improvement in oxygenation parameters. Mean SpO₂ increased from 90.89 ± 1.67% to 93.35 ± 1.83% (p < 0.001), while arterial oxygenation also demonstrated favorable improvement following proning. Hemodynamic evaluation revealed a mild increase in pulse rate during prone positioning. SBP, DBP, and MAP showed gradual reductions over the observation period; however, these changes remained within clinically acceptable limits without evidence of major cardiovascular instability or interruption of prone ventilation. The MAP trend demonstrated progressive decline during proning followed by stabilization after returning to the supine position. Conclusion: Short-duration prone ventilation significantly improves oxygenation while maintaining acceptable hemodynamic stability in mechanically ventilated ARDS patients. The findings support the safety, feasibility, and clinical utility of 8-hour prone positioning as an adjunctive therapeutic strategy in critical care settings when appropriate monitoring is ensured.