米力农联合多巴胺用于重症心内直视术停机过程

Milrinone Combined with Dopamine for Weaning from Cardiopulmonary Bypass in Severe Cardiac Surgical Patients

目的 :观察米力农联合多巴胺对重症瓣膜置换术后脱离体外循环 (CPB)过程全身血流动力学及氧供需平衡影响 ,以评价联合用药对这类病人的治疗效果。方法 :重症瓣膜置换手术病人 2 0例 ,随机分成两组 ,于心脏复跳、建立稳定的自主心律后 ,分别应用小剂量 (A组 )或较大剂量 (B组 )米力农联合多巴胺 ,停机过程经人工心肺机输血、补液维持PADP相对稳定。结果 :A、B两组停机后 ,CI分别较基础值增加 5 0 %和 80 %。B组用药后SVRI的下降幅度明显超过A组 ,同时MAP显著降低 ,多数病人因MAP <8kPa需单次静注去氧肾上腺素治疗。HR变化均不明显 ,PVRI、MPAP及PAWP虽显著降低 ,但两组间差异无显著性。停机后两组病人DO2 I显著增加 ,VO2 I无明显变化 ,而VO2 /DO2 显著降低。结论 :米力农与多巴胺联合应用可明显改善重症心脏手术后心肌收缩功能 ,提高氧的利用率而对全身氧耗无明显影响。但考虑到对MAP的影响 ,在脱离CPB过程 。

Objective:To examine the effects of combination of milrinone and dopamine on systemic hemodynamics and oxygen balance and evaluate its effectiveness during weaning from CPB in severe cardiac surgical patients.Methods:20 patients scheduled for valve replacement were randomly divided to two groups.After aortic cross clamp was removed and adequate cardiac rhythm established,on the basis of dopamine (5μg·kg -1 ·min -1 )infusion,either a low dose of milrinone (group A) or a compared high dose of milrinone (group B)was administered.Patients were transfused from the CPB reservoir to maintain pulmonary artery end diastolic pressure relatively stable during weaning.Results:Patients receiving high dose milrinone had a greater increase of 80% in cardiac index (CI) at 30min after weaning versus 50% in the low dose milrinone group.Group B had a larger decrease in SVRI and MAP than group A after weaning and the majority of patients in group B required intravenous phenylephrine because of MAP lowere than 9kPa.There were no significant changes in HR compared to the baseline between two groups.MPAP,PAWP and PVRI all decreased significantly,but there were no differences between two groups.In all patients, DO 2I increased markedly but VO 2I was unchanged,VO 2I/DO 2I ratio decreased significantly after weaning.Conclusion:Combination of milrinone and dopamine can improve hemodynamics and myocardial contractile function after weaning from CPB in severe cardiac surgical patients without greatly affecting systemic oxygen consumption.As the effect on MAP is concemed,using low dose of milrinone may be safer during weaning.