Vehicle influence on potassium replacement effectiveness in hypokalemic rats.

INTRODUCTION Patients who undergo cardiac surgery are commonly treated with diuretic therapy for the management of volume overload. The concern of hypokalemia important in the adult population submitted to cardiac surgery has been described. Intravenous potassium (K+) replacement dilution is only recommended with sodium chloride 0.9% solution (SF0.9%), likely due to the putative effects of glucose solution 5% (SG5%) on insulin secretion, which influence K+ replacement quality. However, it is not yet experimentally proved the influence of SF0.9% and SG5% on K+ replacement quality. OBJECTIVES To evaluate the effects of different vehicles of K+ replacement on blood K+ levels in furosemide hypokalemic rats. METHODS Male Wistar rats divided into four groups: K++SF, K++SG, SF and SG. Jugular vein was cannulation for K+ replacement and femoral vein was cannulated for blood analysis were performed. Furosemide (50mg/kg) was injected S.C. to induce hypokalemia. It was analyzed potassium plasmatic levels 24 hours before furosemide injection, 24 hours after furosemide injection and 30 minutes after post-replacement. RESULTS There was no significative difference in blood K+ levels when compared to the basal values (pre-furosemide) in all groups. However, the levels [K+] returned to baseline in both groups receiving K++SF or K++SG, which was not observed in groups receiving only SF and SG. Only K+SF presented increased after K+ replacement (P<0.05). CONCLUSION K+ replacement diluted both in SF and SG did not affect blood K+ levels in rats.