ABSTRACT
Objective To evaluate the effect of dexmedetomidine on left ventricular function in patients undergoing coronary artery bypass grafting (CABG) by transesophageal echocardiography (TEE).Methods The study was a prospective,randomized and placebo-control clinical trial.Eighty patients undergoing CABG with cardiopulmonary bypass (CPB) were divided into dexmedetomidine group (group D)and control group (group C) by random digits table method with 40 cases each.A loading dose of dexmedetomidine 0.5 μg/kg was injected intravenously 10 min after induction followed by infusion at 0.4 μ g/(kg· h) until the end of operation in group D,while equal volume of normal saline was given in group C.Left ventricular function was assessed by transesophageal echocardiography before the infusion of dexmedetomidine (T1),at the end of the infusion of loading dose (T2),before CPB (T3) and at the end of the operation (T4).Results Compared with those at T1,left ventricular ejection fraction and fractional area change decreased significantly [(58.0 ± 12.0)％,(60.0 ± 9.6)％ vs.(63.0 ± 8.6)％ and (46.0 ± 9.3)％,(48.0 ± 8.4)％ vs.(51.0 ± 6.7)％] (P ＜ 0.05 or ＜ 0.01),E/A ratio increased significantly (1.05 ± 0.27,1.07 ±0.31 vs.0.98 ±0.19)(P ＜0.05 or ＜0.01) and myocardial performance index (MPI) decreased significantly (0.46 ± 0.14,0.45 ± 0.12 vs.0.51 ± 0.14) (P ＜ 0.05) at T2 and T3 in group D,while stroke volume was not significantly changed (P＞ 0.05).Compared with that in group C,E/A ratio and rapid filling fraction in group D was significantly higher [1.06 ± 0.18 vs.0.97 ± 0.18,(62.0 ± 7.1)％ vs.(58.0 ± 7.3)％],and S/D ratio and MPI was significantly lower at T4(1.17 ± 0.21 vs.1.29 ± 0.22,0.43 ± 0.15 vs.0.50 ± 0.15),and there were significant differences (P ＜ 0.05).There was no difference in the parameters indicating left ventricular systolic function (P ＞ 0.05).Conclusions Dexmedetomidine restrains left ventricular systolic function in the patients undergoing CABG,but does not decrease the cardiac output,and improve relaxation dysfunction of left ventricular diastolic function.Global left ventricular function is improved by dexmedetomidine after CABG.
ABSTRACT
ObjectiveDiabetes is an independent risk factor for coronary artery bypasss grafting(CABG). Off pump coronary artery bypasss (OPCAB) experience in 251 cases was reviewed to determine whether diabetes wou ld be applicable in OPCAB procedures.MethodsConsecutive 251 patients underwent OPCAB over 12 month period. This study included 71 diebetic patients (DM group) and 180 nondiabetic patients (NDM group). Preoperative v ariables were compared between the two groups by univariate analysis.R esultsNo differences were found regarding the length of stay in cardio intensive care unit [DM group(2.4?0.3)d; NDM group (2.4?0.3) d;P=0. 386], and sternal complication (DM group: 5.7%;NDM group: 3.9%;P=0.511) . In hospital complications were as follows: death rate(DM group: 2.8%; NDM gr oup: 1.1%; P=0.680); stroke (DM group: 2 8%; NDM group: 1 7%; P=0 623 ); hemofiltratioin renal failure (DM group: 2.8%; NDM group: 0.5%; P=0.194); myocardial infarction(DM group: 0%; NDM group: 0.5%;P=1.000); blood using were more frequent in DM group comparied with NDM group (P=0.111). ConclusionOPCAB in diabetic patients is as safe as in non diabetic patients.