Comparison of Intra-Abdominal Pressure Among 3 Prone Positional Apparatuses After Changing From the Supine to the Prone Position and Applying Positive End-Expiratory Pressure in Healthy Euvolemic Patients: A Prospective Observational Study

Abstract

Positional apparatuses used for the prone position can affect intra-abdominal pressure (IAP). In this study, we compared the IAP after changing to the prone position and applying various positive end-expiratory pressure (PEEP) levels among 3 prone positional apparatuses. A total of 108 healthy euvolemic patients undergoing elective prone spinal surgery were divided into 3 groups based on the positional apparatus used: the Jackson spinal table was used in group J (n=36), the Wilson frame in group W (n=36), and chest rolls in group C (n=36). The IAP was measured 2 minutes after application of 0, 3, 6, and 9 cm H2O of PEEP. The IAP in the supine position was 6.4±3.0, 5.9±2.8, and 7.1±2.5 mm Hg in groups J, C, and W, respectively. After the supine-to-prone positional change, the IAP in the prone position was significantly lower in group J than in groups C and W (2.7±2.9 vs. 8.9±4.0 and 12.9±4.3 mm Hg, P<0.01). In the prone position, a PEEP of 9 cm H2O increased the IAP from baseline (zero PEEP) by 1.5±1.3, 1.6±1.3, and 1.7±1.0 mm Hg in groups J, C, and W, respectively. The IAP in the prone position was significantly lower using the Jackson table compared with the Wilson frame and chest rolls. A PEEP up to 9 cm H2O can be safely used in healthy euvolemic patients undergoing prone spinal surgery without a clinically significant increase in IAP, irrespective of the type of prone positional apparatus.