Hemodynamic and respiratory alterations with increased intra-abdominal pressure

Abstract

Respiratory and hemodynamic alterations produced by sequential increases in intra-abdominal pressure were studied in 10 dogs. Significant increases in end-inspiratory pressure required to deliver a fixed tidal volume were noted above 25 mm Hg. Despite a normal arterial pressure, there was a marked decline in cardiac output beginning at 10 mm Hg IAP. These findings were paralleled by a decreased inferior vena cava flow suggesting decreased venous return as the mechanism for the reduced cardiac output. There was a close correspondence between intra-abdominal pressure and pressure in the inferior vena cava (as measured through a femoral vein catheter) which suggests that monitoring pressure through the femoral vein may be a clinically useful technique for determining the level of IAP.