Unexplained intraoperative hypotension, acute ischemic hepatitis, and pancreatitis associated with aortorenal bypass surgery

Abstract

A 69-year-old male smoker who had severe atherosclerotic renovascular disease associated with progressive deterioration of kidney function, poorly controlled hypertension, and a 5-cm solid fight renal mass was scheduled for partial nephrectomy and hepatorenal bypass. He had no history of other cardiovascular disease or prior abdominal surgery. The physical examination was unremarkable except for a blood pressure of 170/90 mmHg. Laboratory studies included normal white blood cell count, hematocrit, platelet count, liver function tests, and clotting characteristics. The blood urea nitrogen concentration was 25 mg/dL (normal, 8 to 25 mg/dL); creatinine, 2.2 mg/dL (normal, 0.7 to 1.4 mg/dL); and creatinine clearance, 25 mL/min. Carbon dioxide arteriography was performed 1 month before the surgery and showed bilateral proximal 80% renal artery stenosis. A lateral aortogram showed a mild proximal celiac trunk stenosis with patent splenic, hepatic, and superior mesenteric arteries, and occluded inferior mesenteric artery. The right hepatic artery originated from the superior mesenteric artery and had a 50% to 60% osteal stenosis. The preoperative electrocardiogram and thallium stress test were normal; a carotid duplex ultrasound showed a 40% to 59% stenosis of the fight internal carotid artery. Under general endotracheal anesthesia (induction and endotracheal intubation with 150 mg of propofol and 10 mg of vecuronium, and maintenance with oxygen, nitrous oxide, and isoflurane), a bilateral subcostal incision was made, and a Bookwalter retractor was positioned. At exploration, a decreased pulse was noted in the porta hepatis area; therefore, an aortorenal rather than a hepatorenal bypass was performed. After resection of the kidney mass under cold ischemia (duration, 45 minutes), the anterolateral side of the aorta was clamped, and an aortorenal bypass with a reversed greater saphenous vein graft was performed with warm ischemia time of 25 minutes. The patient received no systemic heparinization and only regional arterial heparin flushes (up to 1,000 U) were used during the revascularization. The operation lasted about 4 hours. During the first 2 hours, the systolic blood pressure was between 100 and ll0 mmHg, and a continuous intravenous dopamine drip (dose, 1 to 3 ~tg/kg/min) was administered. The central venous pressure was 15 to 18 mmHg. During the last 2 hours of the surgery, the systolic blood pressure was maintained between 90 to 100 mmHg (despite relatively low blood loss and light anesthesia with 0.2% to 0.3% isoflurane) with increased fluid administration, and dopamine and epinephrine infusions at 12 ~g/kg/min and 0.03 to 0.07 pg/kg/min, respectively. The estimated blood loss during the entire operation was 1,500 mL, and the patient received 2 U of packed red blood cells. In