应用胸腔阻抗法评估手术和麻醉对患者血流动力学的影响

Evaluation of operation and anesthesia on hemodynamic variables in patients undergoing elective abdominal surgery by noninvasive thoracic bioimpedance technique

目的 通过无创心排血量监测仪 ,评价手术和麻醉对腹部择期手术患者血流动力学的影响。方法 应用 He Mo 6 0 1生物阻抗系统 ,分别于术前 1d、术后 4～ 6 h和 2 4 h对 32例腹部择期手术患者进行血流动力学监测 ,并比较心排血量 (CO)、心排指数 (CI)、每搏心排血量 (SV)、每搏心脏做功 (SW)、心脏每分做功(CW、)左室舒张末压 (L VEDP)和心率 (HR)的变化。结果 CO、CI、CW和 L VEDP在术后 2 4 h内的改变与术前比较均无显著性差异 (P均 >0 .0 5 )。术后 4～ 6 h的 SV和 SW比术前有明显降低 (P均 <0 .0 5 ) ,而术后 2 4 h的 SV和 SW与术前相比则无显著性差异 (P均 >0 .0 5 )。术后 4～ 6 h HR明显快于术前 (P<0 .0 5 ) ,但术后 2 4h HR与术前相比无显著性差异 (P>0 .0 5 )。结论 术后 4～ 6 h SV和 SW值的降低可能与麻醉使心肌收缩力减弱有关 ,HR明显增快则是 SV和 SW降低后机体产生代偿机制的结果。最大程度地保证术中及术后充足的输液量 ,对维持 CO、CI以及维护组织血液灌注具有重要意义。

Objective To analyse and discuss the effects of elective abdominal operation and anaesthesia on patients' cardiac output via noninvasive thoracic bioimpedance technique. Methods Noninvasive monitoring system HeMo-601 was applied to detect the hemodynamic variables of 32 elective abdominal surgery patients.The clinical data of cardiac output(CO), cardiac index(CI), cardiac working per minute(CW), left ventricular end-diastolic pressure(LVEDP), stroke volume(SV), cardiac stroke working(SW)and heart rate (HR) were analysed at 1 hour before operation, 4-6 hours after operation and 24 hours after operation, respectively. Results No significant differences were found in CO, CI, CW and LVEDP between various time points and preoperation(all P>0.05). SV and SW at 4-6 hours after operation were significant lower than those before operation(all P<0.05). Whereas, SV and SW at 24 hours after operation were no significant differences compared with those before operation(all P>0.05). As compared with preoperation, HR at 4-6 hours after operation was significantly faster(P<0.05). However, there was no significant difference in HR between 24 hours after operation and preoperation(P>0.05). Conclusion The reductions in SV and SW at 4-6 hours after operation might be a result of anaesthesia that could weaken the contraction of heart. The presence of rapidness of HR at 4-6 hours after operation might be a compensatory mechanism for the decreases in SV and SW. Therefore, optimizing adequate infusion by the greatest extent during and after operation is very crucial for the maintenance of CO, CI and tissue perfusion.