The protective effect of dexmedetomidine on erythrocyte in patients undergoing cardiac valve replacement during perioperative period

Abstract

Objective To investigate the protective effect of intraoperative and postoperative dexmedetomidine(Dex) on erythrocyte glucose metabolism and lipid peroxidation in patients undergoing heart valve replacements with cardiopulmonary bypass(CPB). Methods Sixty patients undergoing elective heart valve replacements with CPB were randomly divided into control group (group C, n=30) and Dex group (group D, n=30) by random number table method. The patients in group D were intravenously infused 0.5-1.0 μg/kg Dex 15 min before operation, followed by an infusion at a rate of 0.5 μg·kg-1·h-1 until the end of the operation. In group C, Dex was not administered during or after surgery but the same dose of normal saline was injected at the same time and through the same route. The patient-controlled intravenous analgesia (PCIA) was used for postoperative analgesia. PCIA solution in group D contained sufentanil 2 μg/kg+Dex 4 μg/kg in 100 ml of normal saline. PCIA solution in group C contained sufentanil 2 μg/kg in 100 ml of normal saline. Infusion rates in both groups were 2 ml/h. The blood glucose, erythrocyte phosphofructokinase (PFK), glucose-6-phosphate dehydrogenase(G-6PD), aldose reductase(AR) activity, erythrocyte lipid peroxidation(ELPO) and glutathione (EGSH) were detected before induction of anesthesia(T1), at the time of leaving operation room (T2), at the time of the first postoperative day (T3) and at the time of the second postoperative day(T4). Results Compared with values of these parameters at T1, the levels of blood glucose, G-6PD, AR and ELPO in group C were significantly increased at the time points of T2 and T4 (P<0.05). The levels of PFK and EGSH in erythrocytes were significantly decreased at the time points of T2 and T4 (P<0.05). Compared with group C, the blood glucose, G-6PD, AR, ELPO were significantly decreased (P<0.05). The erythrocyte PFK and EGSH levels were significantly increased in group D(P<0.05). Conclusions Intraoperative and postoperative Dex therapy can significantly improve erythrocyte glucose metabolism and enhance the antioxidant capacity of erythrocytes after cardiac valve replacement with CPB. Key words: Dexmedetomidine; Cardiopulmonary bypass; Erythrocytes; Glucose metabolism disorders; Lipid peroxidation