Ischemic liver dysfunction after elective repair of infrarenal aortic aneurysm: Incidence and outcome

Objective: To assess the frequency of early postoperative liver dysfunction in patients undergoing elective infrarenal aortic aneurysm repair, their hospital course, and outcome. Design: A retrospective case- control study. Setting: A single tertiary referral center. Participants: A review of medical records of 942 consecutive asymptomatic patients with normal preoperative liver function test results who had elective infrarenal aortic aneurysm repair with infrarenal aortic cross-clamping. The authors selected all patients who had an acute increase in serum hepatic enzyme levels (minimum fivefold increase in aspartate aminotransferase [AST] and twofold increase in lactate dehydrogenase [LDH] levels) within the first 7 perioperative days (study patients). The control group consisted of 42 patients with normal postoperative liver function test results, matched by age, sex, and year of surgery to study patients. Interventions: None. Measurements and Main Results: Aortic cross-clamping times, lowest intraoperative blood pressure, duration of hypotension (systolic blood pressure ≤95 mmHg), lowest intraoperative base deficit, and estimated blood loss were compared between control and study patients. The study also analyzed perioperative metabolic, hemostatic, hepatic, and renal function variables; the intraoperative course; postoperative complications; and inhospital outcome. Fourteen of 942 patients (1.5%) comprised a study group. In 11 patients (1.2%), AST and LDH levels moderately increased, and three patients (0.3%) developed changes consistent with a diagnosis of acute ischemic hepatitis (AIH). In all patients, the serum liver enzyme levels peaked between 24 and 72 postoperative hours. Three patients with AIH developed concomitant acute renal failure; one had associated disseminated intravascular coagulation (DIC) and died. Of 11 patients with moderate increases, one subsequently developed multisystem organ failure and died. The overall in-hospital mortality rate for patients with postoperative liver dysfunction was 14% (2/14) and for the control group it was 2.3% (1/42). The duration of hypotension and metabolic acidosis were more pronounced in patients who postoperatively developed liver dysfunction (both p < 0.001); however, study and control patients did not differ in the duration of aortic cross-clamping, lowest intraoperative blood pressure, or estimated blood loss. Conclusion: Liver enzyme levels acutely increased in 1.5% of patients after elective infrarenal aortic aneurysm repair with infra renal cross- clamping. In patients with moderately elevated serum liver enzyme levels, postoperative recovery was relatively uncomplicated, whereas all three patients with AIH developed acute renal failure and had a more complicated postoperative course. Those with postoperative liver dysfunction had a longer duration of intraoperative hypotension and more pronounced metabolic acidosis.