全麻复合硬膜外阻滞对老年人单肺通气的影响

目的：观察全麻复合胸段硬膜外阻滞对老年人单肺通气期间动脉血气及肺内分流的影响。方法：选择ASA Ⅰ-Ⅱ级择期开胸手术老年患者82例，随机分为两组，全麻复合硬膜外阻滞（GEA）组和全麻（GA）组，每组41例。两组患者在开胸前双肺通气15min（T1）时及开胸后单肺通气（OLV）10min（T2）、30rain（T3）、60min（T4）时，分别采动脉血及混合静脉血，观察患者动静脉血气情况并计算肺内分流率（Qs／Qt）值，记录血流动力学数据。结果：两组患者麻醉后手术中心率（HR）和平均动脉压（MAP）均较稳定，GEA组平均动脉压、心率麻醉后较麻醉前明显下降（P〈0．05），各对应时点也明显低于GA组（P〈0．05），末梢血氧饱和度（SpO2）麻醉插管后较麻醉前上升，单肺通气后无明显下降趋势；所有患者pH值、PO。、PaCO：均在正常范围内；PaO2插管后明显上升（P〈0．05），但单肺通气后各时点较通气前明显下降，GEA组较GA组下降更明显（P〈0．05）；QS／QT值单肺通气后各时点较通气前明显上升（P〈0．05），GEA组较GA组升高更明显（P〈0．05）。结论：全麻复合硬膜外阻滞用于老年患者单肺通气期间可增加肺内分流，使PaO2有所下降，但在正常范围内，围术期应严密加强血气监测，维持好血流动力学的稳定以提高手术麻醉的安全性。

Influence of General Anesthesia Combined with Epidural Block on the Aged during One-lung Ventilation in Patients Undergoing Thoracic Surgery

Objective：To evaluate the influence of general anesthesia combined with thoracic epidural block on arterial blood gas and intrapulmonary shunt during one-lung ventilation in patients undergoing thoracic surgery. Methods：Eighty-two patients with ASA grade Ⅰ -Ⅱ and undergoing elective thoracic surgery were randomly divided into two groups the general anesthesia combined with thoracic epidural block group（group GEA,n = 41）and single general anesthesia group（group GA,n = 41）. Arterial blood gas and mixed vein blood gas were analyzed and Qs/Qt was calculated in both groups at 15min（T~ ） after two-lung ven- tilation and 15 rain （T2）. 30min（T3 ） and 60 min（T4） after one-lung ventilation and record the data of hemodynamics. Results： Blood pressure and heart rate after anesthesia descended significantly in GEA group（P〈0.05）, the same was between GEA and GA（P〈0.05）. No significant change was found in arterial blood PaCO2, pH and PO2 during one-lung ventilation. PaO2 increased significantly after intubation（P〈0.05）. Qs/Qt increased while PaO2 decreased significantly（P〈0. 05） after one-lung ventilation was performed in both groups. Compared to group GA, Qs/Qt were significantly higher and PaO2 were markedly lower in group GEA at T2-4 and decreased significantly （P%0.05） after one-lung ventilation was performed in both groups.Conclusion： During one lung ventilation,general anesthesia combined with thoracic epidural block increases Qs/Qt and decreases PaO2 but still in normal range. In this case, blood gas should be monitored carefully and maintain stead hemodynamic during surgery to improve the safety of anesthesia.