Aim: To investigate the effectiveness of insulin on decreasing serum potassium concentration during anhepatic stage of orthotopic liver transplantation.
Methods: 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.
Results: 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.
Conclusion: 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.