A prospective comparative study of the effect of supine and prone position on respiratory mechanics in patients undergoing elective surgery in prone position under general anesthesia

Background: The prone position is associated with compromised compliance of the respiratory system. As the abdomen is compressed and the movement of the chest wall is restricted. In spine surgery, patients may face problems with ventilation. For surgeons and for anesthesiologists, the prone position is a problem. Cardiac function may be affected. Objective: The objective of this study was to study the effect of supine and prone position on respiratory mechanics in patients undergoing elective surgery in the prone position under general anesthesia. Materials and Methods: Hospital-based, prospective-comparative study was conducted on 60 patients. Baseline values of oxygen saturation (SpO 2 ), end tidal carbondioxide (ETCO 2 ), systolic blood pressure, diastolic blood pressure, mean arterial pressure, heart rate (HR), peak airway pressure (P peak ), peak mean pressure (P mean ), and dynamic lung compliance (DLC) were measured in supine position. Same parameters were measured after changing position from supine to prone recorded at different time intervals and then measured after positioning patient from prone to supine at 5 and 10 min. Results: P peak was 18.7. P mean was 8.1. Mean HR was 82.3/min. P peak , P mean , DLC, significantly increased while change from supine to prone position at 5 and 30 min. But not increased significantly while change from prone to supine position. ETCO 2 remained same while change from supine to prone position at 5 and 30 min. But significantly decreased while change from prone to supine position. SpO 2 decreased at all times in all position changes. Conclusion: The present study found a significant effect of the positioning of patients on respiratory mechanics in patients undergoing elective surgery in the prone position under general anesthesia.