长时间异丙酚麻醉不伴有血乳酸值的增加

背景乳酸酸中毒被认为是异丙酚输注综合征的一种早期信号。本次研究中，我们考察长时间异丙酚麻醉和吸入麻醉下血乳酸和pH的改变。方法选择长达8小时以上择期脊柱手术患者并对麻醉期间记录数据作回顾性分析。在麻醉时间（anesthesia time，AT）（±30分钟）与失血量（blood loss，BL）（±500m1）的前提下，异丙酚麻醉与吸入麻醉的患者人数匹配比为1：2。结果在合乎条件的246例患者中，50例患者接受异丙酚麻醉[AT=（10±2）小时，BL=（1955±1409）m1]，而匹配100例吸入麻醉患者[AT=（10±1）小时，BL=（1801±1543）ml]。其中分别有40例和72例患者具有完整的基础值和麻醉后8小时乳酸值，包含在主要的分析资料中。异丙酚组接受（8．8±2）mg·kg^-1·h^-1的异丙酚。吸入组患者年龄较异丙酚组大[（58±12）岁vs（51±15）岁，P=0．002]，但两组在性别、ASA分级、术中血流动力学改变和血管升压药物使用方面没有差异。8小时之后，吸入组血乳酸值比异丙酚组相对各自基础值水平上有较大的增加[高于基础值的改变：异丙酚，（0．48±0．72）mmol／L；吸入麻醉，（1．2±1．2）mmol／L。P=0．001]。结论在超过8小时的长时间脊柱手术中，吸入麻醉与异丙酚麻醉相比，更易伴有血乳酸值升高。需要前瞻性的研究以解释该发现的确切机制和临床意义。

BACKGROUND： Lactic acidosis is considered an early sign of propofol infusion syndrome. In this study, we investigated the changes in lactate and pH with propofol versus volatile anesthesia （VA） of long duration. METHODS： Demographic and intraoperative data were recorded retrospectively from the anesthesia records of patients who underwent elective spine surgery longer than 8 h. Propofol patients were matched 1 ： 2 to VA patients, based on anesthesia time （AT） （30 min） and blood loss （BL） （ ±500 ml）. RESULTS： Of 246 patients identified, 50 received propofol （AT = 10±2 h, BL = 1955±1409 ml） and were matched to 100 VA cases （AT = 10 ± 1 h, BL = 1801±1543 ml）, and of those, 40 and 72 patients, respectively, had complete lactate data at baseline and at 8 h after anesthesia and were included in the main analysis. The propofol group received 8.8±2mg·kg^-1·h^-1 of propofol. The VA group age was older than the propofol group （58±12 vs 51±15 yr, respectively, P = 0.002）, but there was no difference between the groups in gender, ASA grade, intraoperative hemodynamic variables, and use of vasopressors. After 8 h, the VA group had a larger increase in arterial lactate from baseline compared with the propofol group （change from baseline： propofol, 0. 48±0.72 mmol/L; VA, 1.2±1.2 mmol/L, P = 0.001 ）. CONCLUSIONS： During prolonged spine surgery 〉8 h, VA was associated with higher serum lactate, when compared with propofol infusion. Prospective studies are needed to elucidate the exact mechanisms and clinical implications of this finding.