摘要目的：评价不同机械通气模式对后路腰椎椎体间植骨融合术（PLIF）患者术中及术后失血量的影响。方法选取择期接受PLIF的患者共88例，按照随机数字表法分为压力控制通气组（PCV组，n=44）和容量控制通气组（VCV组，n=44）两组，分别采用压力控制通气模式和容量控制通气模式进行机械通气。分别于麻醉诱导即刻（T0）、仰卧位改为俯卧位后10 min（T1）、皮肤缝合即刻（T2）、俯卧位改为仰卧位后10 min（T3）及气管导管拔管时（T4）连续监测平均动脉压（MAP）、心率（HR）及中心静脉压（CVP），并于上述时间点分别测定两组患者血红蛋白（Hb）及红细胞压积（Hct）。记录T0～T3时的呼吸参数。记录两组患者术中失血量、术后72 h失血量、异体输血情况、补液量及二次手术止血率。结果与VCV组比较，PCV组于T1～T3时的气道峰压（PIP）均明显降低（P<0.05）。VCV组和PCV组间不同时点的MAP、HR、潮气量、RR、PaO2/FiO2及PaCO2差异均无统计学意义（P>0.05）。两组间患者各时点Hb及Hct差异均无统计学意义（P>0.05）。与VCV组比较，PCV组术中失血量、血浆输注量及红细胞输注量均明显降低（P<0.05）。结论术中给予PCV通气模式可降低接受PLIF术患者术中的失血量，其原因可能与术中更低的气道峰压有关。

abstractsObjectiveTo investigate the effect mechanical ventilation mode on intra-and postoperative blood loss in patients undergoing posterior lumbar interbody fusion (PLIF) surgery.Methods According to the random number table method, a total of 88 patients scheduled to undergo lumbar spine surgery were randomly divided into two groups. Patients were received pressure controlled ventilation and volume controlled ventilation in pressure controlled ventilation (PCV group,n=44) and volume controlled ventilation (VCV group,n=44). Mean arterial pressure (MAP), heart rate (HR) and central venous pressure (CVP) were monitored at the onset of anesthesia induction (T0), 10 min after supine position to prone position (T1) and skin closure immediately (T2), 10 min after prone position to supine position (T3) and when tracheal extubation (T4) respectively, and were determined at the above time points of two groups of hemoglobin (Hb) and hematocrit (Hct).The respiration parameters were recorded from T0 to T3. The indicators were recorded in the two groups as following: the volume of intranperative blood loss, 72 h postoperative blood loss, the volume of allogeneic blood transfusion, the volume of fluid input and the rate of re-operation for stopping the bleeding.Results Compared with VCV group, peak inspiratory pressure (PIP) were all lower increasingly from T1 to T3 in PCV group (P<0.05). There was no statistical significance in MAP, HR, tidal volume, RR, PaO2/FiO2 and PaCO2 at different time points between VCV group and PCV group (P>0.05). The differences of Hb and Hct at different time points between the two groups have no statistical significance (P>0.05). Compared with VCV group, the volume of intranperative blood loss, the amount of transfused plasma and red blood cells were all notably lower in PCV group (P>0.05).Conclusion Intraoperative PCV can decrease intraoperative blood loss in patients undergoing PLIF, which may be related to lower intraoperative peak inspiratory pressure.