胸腔阻抗法对乌拉地尔治疗心力衰竭血流动力学变化的观察

目的：观察胸腔阻抗法对乌拉地尔治疗心力衰竭(心衰)的血流动力学变化。方法：16只健康杂种犬麻醉后，制成心衰模型。分为乌拉地尔组和生理盐水对照组，分别于用药前及用药后15、30、60、90和120min用无创血流动力学监测仪测定心率(HR)、每搏量(SV)、心排血量(CO)、射血前时间(PEP)、左室射血时间(LVET)、收缩时间比率(STR，PEP／LVET)、等容舒张时间(IRT)、肺毛细血管楔压(PCWP)、左室舒张末压(LVEI)P)、总外周阻力(TPR)、每搏左室作功(SW)和每分左室作功(CW)。结果：乌拉地尔较对照组明显增加CO和SV，缩短PEP和STR，降低PCWP、LVEDP和TPR，增加SW和CW，而对HR、LVET和IRT无影响。结论：胸腔阻抗法可作为无创、实时和准确的监测方法观察心衰治疗的血流动力学变化；乌拉地尔可以明显降低心脏前后负荷，增加CO和心肌收缩能力，具有改善心功能的作用。

Observation on the effects of urapidil on hemodynamics in heart dysfunction dogs by thoracic electrical bioimpedance

OBJECTIVE: To observe the effects of urapidil on hemodynamics in heart dysfunction dogs by thoracic electrical bioimpedance. METHODS: Sixteen health anesthesia dogs were taken pentobarbital till their hearts dysfunction. Then 10 dogs were taken urapidil injection (4 microg x kg(-1) x min(-1)) and 6 dogs were taken the same doses of normal saline, and heart rate (HR), stroke volume (SV), cardiac output (CO), pre-ejection period (PEP), left ventricular ejection time (LVET), systole time ratio (STR), isovolumic relaxation time (IRT), pulmonary capillary wedge pressure (PCWP), left ventricular end-diastolic pressure (LVEDP), total peripheral resistance (TPR), stroke work (SW) and cardiac work (CW) were continuously monitored by non-invasive hemodynamic monitoring system. Data were recorded at 15 minutes, 30 minutes, 60 minutes, 90 minutes and 120 minutes after dysfunction. RESULTS: Compared to the group of normal saline, urapidil could increase CO and SV, shorten PEP and STR, decrease PCWP, LVEDP and TPR, increase SW and CW. CONCLUSION: The change of hemodynamics in heart dysfunction dogs can be observed, non-invasively and accurately, by thoracic electrical bioimpedance. Urapidil can obviously decrease preload and postload of heart, increase CO and myocardial contract potentiality, and improve heart function.