Gastric Intramucosal pH and Hepatic Venous Oximetry after Cardiopulmonary Bypass in Valve Replacement Patients

Abstract

To determine splanchnic perfusion after cardiopulmonary bypass, gastric intramucosal pH (pH₁) and hepatic venous oxygen saturation (S_HVO₂) were measured in 14 patients with cardiac valve replacement. Blood samples were analysed at 6, 12 and 24 h after admission to an intensive care unit. Gastric pH₁ increased significantly (P <0.01) from 7.21 at 6h to 7.31 at 12 h and increased to 7.37 at 24 h while S_HVO₂ increased significantly (P <0.05) from 48% at 6 h to 57% at 12 h and 24 h. Cardiac index was >41/min per m² and mixed venous oxygen saturation >70%. Despite sufficient cardiac output, splanchnic perfusion decreased after cardiopulmonary bypass and recovered within 24 h after admission to the intensive care unit. It is concluded that gastric pH₁ and S_HVO₂ are useful parameters for monitoring postoperative splanchnic perfusion in patients with open-heart surgery. Copyright © 1996 The International Society for Cardiovascular Surgery.