Gastric intramucosal pH and hepatic venous oximetry after cardiopulmonary bypass in valve replacement patients.

To determine splanchnic perfusion after cardiopulmonary bypass, gastric intramucosal pH (pH(i)) and hepatic venous oxygen saturation (SHVO2) 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 pH(i) increased significantly (P < 0.01) from 7.21 at 6 h to 7.31 at 12h and increased to 7.37 at 24 h while SHVO2 increased significantly (P < 0.05) from 48% at 6 h to 57% at 12 h and 24 h. Cardiac index was > 4 l/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 pH(i) and SHVO2 are useful parameters for monitoring postoperative splanchnic perfusion in patients with open-heart surgery.