Acid-base changes during liver transplantation using Stewart's physicochemical approach: living related donor vs. cadaveric donor

ABSTRACT

BACKGROUND: Intraoperative acid-base imbalance frequently occurs during liver transplantation (LT). The purpose of this study was to compare the acid-base changes between cadaveric whole LT and a LT from a living relative using a strong ion approach. METHODS: Twenty-four patients undergoing LT were allocated to a group receiving a LT from a brain dead donor (BD group, n = 12) or a LT from a living, related donor (LD group, n = 12) according to the surgical technique required. Acid-base parameters such as PaCO2, pH, base excess, and serum concentrations of bicarbonate, albumin, lactate, phosphate, and other electrolytes were measured at 30 min after skin incision (T1), 30 min after reperfusion (T2), and 1 h after the arrival at the intensive care unit (T3). The apparent strong ion difference (SIDa), the effective strong ion difference (SIDe), and the strong ion gap (SIG) were calculated using the Stewart equation. RESULTS: There were no significant differences in pH, PaCO2, base excess, SIDa, and SIG between the two groups throughout the entire period of investigation. pH was decreased from T1 to T2, and increased significantly from T2 to T3 in both groups. The serum concentration of lactate was significantly increased from T1 to T2 and T3 in both groups without any intergroup differences. The strong ion gap was significantly increased from T1 to T2 only in the BD group. CONCLUSIONS: During LT from both cadaveric and living related donors, there is a biphasic acid-base change that is characterized by an initial metabolic acidosis and then a metabolic alkalosis, with no significant intergroup differences in acid-base variables.