Effects of left stellate ganglion block on cardiac function in patients undergoing coronary artery bypass grafting

Abstract

Objective To investigate the effects of left stellate ganglion block (SGB) on the cardiac function in patients undergoing coronary artery bypass grafting (CABG). Methods Thirty-eight ASA Ⅱ or Ⅲ patients of both sexes aged 42-64 yr undergoing CABG were randomly divided into 2 groups ( n = 19 each) : control group (C) and SGB group. The patients were premedicated with intransuscular midazolam 5 mg, morphine 10 mg, premethazine 25 nag and penehyclidine 1 mg. Radial artery was cannulated. Swan-Ganz catheter was placed via right internal jugular vein. SGB was performed via anterior approach. 1% fidocaine 10 ml was injected. Successful block was verified by development of Homer syndrome. EGG, SpO2, MAP, HR, cardiac output (CO), CVP, mean pulmonary arterial pressure (MPAP) and pulmonary artery wedge pressare (PAWP) were monitored during anesthesia. Cardiac index (CI), stroke index (SI), systemic vascular resistance (SVR), pulmonary vascular resistance (PVR), and left and right ventricular stroke work index (LVSWI, RVSWI) were calculated. CO, HR, MAP, CVP, MPAP, PAWP, EI, SI, SVR, PVR, LVSWI, and RVSWI were recorded before SGB (T0) and 5, 10 and 15 min after SGB (T1-3). Results CO and CI at T1,2, RVSWI at T2 were significantly higher while CVP at T1-3 and PAWP at T3 were significantly lower in SGB group than in control group. RVSWI was significantly increased as compared with the baseline at To in SGB group. Conclusion Left SGB can increase cardiac output and improve cardiac function in patients undergoing CABG. Key words: Nerve block; Stellate ganglion; Heart function tests; Coronary artery bypass