Effect of dexmedetomidine on perioperative cardiac function in patients with mild cardiac dysfunction undergoing laparoscopic surgery

Abstract

Objective To investigate the effect of dexmedetomidine on perioperative cardiac function in patients with mild cardiac dysfunction undergoing laparoscopic radical resection of rectal cancer. Methods Sixty patients scheduled with laparoscopic radical resection of rectal cancer with mild heart failure were selected, with New York Heart Association (NYHA) cardiac function gradingⅠ to Ⅱ, American Association of Anesthesiologists (ASA) grading Ⅱ to Ⅲ, and age from 63 to 72 years. The patients were divided into dexmedetomidine group (group D) and control group (group C) according to the random digits table method with 30 cases each. At the beginning of induction, the patients in group D were given intravenous infusion a loading dose of dexmedetomidine at 0.5 μg/kg for more than 10 min. Then continuous intravenous infusion of dexmedetomidine was given at 0.3 μg/(kg·h) for 60 min. The patients in group C were given 0.9% sodium chloride with the same method. The small vessel resistance (SVR), left ventricular end-diastolic volume (LVEDV), left ventricular ejection fraction (LVEF), cardiac output (CO) and myocardial working index (Tei index) before induction (T0) and after administration of 20 min (T1), 40 min (T2), 60 min (T3) were measured by color Doppler ultrasound, and the heart rate (HR) and mean arterial pressure (MAP) were recorded at the same times. The time from the end of operation to extubation and incidences of agitation during recovery period were recorded. Results The T1 to T3 SVR in group D were significantly lower than those of T0: (883 ± 30), (827 ± 36) and (804 ± 38) dyn·s·cm-5 vs. (1 075 ± 37) dyn·s·cm-5, and there were statistical differences (P 0.05); compared with those in group D, the T1 to T3 CO in group C were significantly lower: (3.4 ± 0.6) L/min vs. (4.4±1.0) L/min, (3.2 ± 0.7) L/min vs. (4.3 ± 0.8) L/min and (3.3 ± 0.9) L/min vs. (4.4 ± 0.9) L/min, and there were statistical differences (P 0.05); compared with those in group D, the T1 to T2 LVEF in group C were significantly lower, and there were statistical differences (P 0.05); compared with group D, the T1 to T2 Tei index in group C were significantly higher, and there were statistical differences (P 0.05). In group D, the T1 to T3 HR were significantly lower than T0: (68.1 ± 12.8), (67.3 ± 11.9) and (65.4 ± 11.7) times/min vs. (88.2 ± 15.1) times/min, and there were statistical differences (P 0.05). The incidence of agitation during recovery period in group D was significantly lower than that in group C. Conclusions Dexmedetomidine can effectively promote the perioperative cardiac function recovery in patients with cardiac dysfunction undergoing laparoscopic radical resection of rectal cancer, suggesting that it has a certain myocardial protection effect. Key words: Laparoscopy; Dexmedetomidine; Cardiac dysfunction