小剂量瑞芬太尼降低心脏手术血流动力学反应的研究

Low-dose remifentanil to suppress haemodynamic responses to noxious stimuli in cardiac surgery

目的:探索国产瑞芬太尼用于心脏手术的较低的有效剂量。方法:选择68例首次接受择期心脏直视手术患者,ASA≤Ⅲ级,根据4个不同剂量的瑞芬太尼0.1,0.2,0.3或0.4μg/(kg.min),随机分为四组(即R1,R2,R3或R4组)。以脑电双频指数(BIS)监测指导和调控依托咪酯的恒速输注,分别复合不同剂量的瑞芬太尼持续泵注的全凭静脉麻醉,研究心脏手术转流前各种伤害性刺激(气管插管、切皮、锯胸骨3个事件点)对血流动力学的影响,并分别记录各事件点前后的平均动脉压(MAP)、心率(HR)、心脏指数(CI)、每搏指数(SI)、外周血管阻力指数(SVRI)、加速度指数(ACI)以及BIS值。MAP、HR或二者同时增加超过基础值的20%,视为有临床意义,表明这些患者对伤害性刺激有反应。结果:四组间及各事件点前后的CI、SI、SVRI、ACI和BIS值无统计学意义。R3和R4组的剂量能较好地预防MAP和HR的增加(P(0.05)。结论:瑞芬太尼0.3或0.4μg/(kg.min)复合依托咪酯恒速输注在体外循环转流前可以减轻应激刺激的血流动力学反应,并可等同于来自相关文献的更高剂量瑞芬太尼而不影响心脏泵的功能。

Objective ： To search for an optimal low dose of remifentanil that may cause fewer adverse events and effectively suppress haemodynamic responses to typical stressful stimuli. Methods： Sixtyeight patients （ ASA ≤Ⅲ ） undergoing cardiac surgery were assigned to 4 dose groups （ R1, R2, R3 and R4） and received total i.v. anaesthesia of constant administration of etomidate with continuous infusion of remifentanil at the dose of 0.1,0.2, 0.3 or 0.4 μg/（ kg · min）, respectively. Subsequently, changes in MAP, HR, CI, SI, SVRI and ACI were recorded for 5 minutes. A 20% increase over the baseline in MAP and / or HR was considered to be of clinical significance, showing the patient to be a responder to noxious stimuli. And the brain information service （BIS） was monitored and directed to show the level of anesthesia. Results： CI, SI, SVRI, ACI and BIS values showed no significant differences among the four dose groups at different time points. There were fewer responders in the latter two groups （P 〈 0.05 ）. Conclusion ： Remifentanil at 0.3 or 0.4 μg/（ kg . min） in combination with continuous infusion of etomidate in the pre-bypass period may mitigate potentially hazardous haemodynamic responses to stressful stimuli, which can be as effective as the higher doses of remifentanil reported in relevant literature.