Effect of insulin on hyperkalemia during anhepatic stage of liver transplantation

To investigate the effectiveness of insulin on decreasing serum potassium concentration during anhepatic stage of orthotopic liver transplantation.

Sixteen patients with serum potassium concentrations greater than 4.0 mmol/L at the onset of anhepatic stage were randomized into two groups. The patients in control group (n = 8) received no treatment, while those in treatment group (n = 8) received an intravenous bolus injection of regular insulin (20 U) 10 min into the anhepatic stage, followed by a glucose infusion (500 mL 50 g/L dextrose) over 15 min.

In control group, potassium concentration underwent no changes whereas in treatment group, it decreased from 4.8+/-0.48 mmol/L to 4.19+/-0.55 mmol/L (mean+/-SD) within 15 min and to 3.62+/-0.45 mmol/L 60 min after the therapy. The potassium concentration was lower in treatment group than in control group within 30 min of treatment (3.94+/-0.57 vs 4.47+/-0.42 mmol/L, respectively; P<0.05), and increased similarly 30 s after graft reperfusion in both groups of patients, but remained lower in treatment group (5.81+/-1.78 vs 7.44+/-1.75 mmol/L, respectively; P<0.05). The potassium concentration returned to pre-reperfusion levels within 5 min after graft reperfusion.

In patients undergoing orthotopic liver transplantation, the administration of insulin rapidly decreases serum potassium concentration even in the absence of the liver, suggesting an important contribution by extrahepatic tissues in insulin-stimulated uptake of potassium.