Analysis of the components of hypertransaminasemia after liver resection

Background. The increase in plasma aspartate (AST) and alanine (ALT) aminotransferase after liver resection is multifactorial, and a major problem is the difficult quantification of the impact of each involved factor. Methods. A large series of measurements obtained from 92 hepatectomized patients was processed by regression analysis to assess in detail the postoperative evolution of AST and ALT, together with the related components. Results. The best correlate of the increased AST and ALT at postoperative day 1 was the duration of surgery (T-surg) (r2=0.31 and 0.29, respectively), with a lesser contribution of intraoperative liver ischemia (T-isch) (r2=0.22 and 0.17, respectively)(p<0.001 for all). Subsequently AST decreased faster than ALT and both followed an inverse exponential pattern. T-surg, T-isch, distance from surgery and plasma bilirubin explained 77% and 51% of the variability of AST and ALT, respectively, in all postoperative measurements (p<0.001 for both). The best correlate of T-isch was a delayed increase in bilirubin, detected at postoperative day 7, attenuated by the use of intermittent liver ischemia. Conclusion. These data show that T-isch may not be the main determinant of increased transaminases after hepatectomy, and quantify the distinct impact of the trauma of liver resection, liver ischemia, and other factors on the postoperative evolution of transaminases.