心脏瓣膜手术中低脑氧发生情况及其对早期预后的影响

Occurrence of hypoxia in heart valve surgery and its effect on early prognosis

目的探讨心脏瓣膜手术中低脑氧发生情况及其对早期预后的影响。方法纳入2017年8月至2018年5月于四川大学华西医院在浅低温体外循环(CPB)下行择期心脏瓣膜手术的患者190例。术中监测患者双侧局部脑组织氧饱和度(rScO_(2)),定义患者术中出现rScO_(2)<55%持续5 min为低脑氧事件,根据是否发生低脑氧事件分为低脑氧组(L组)和正常脑氧组(N组)。比较两组临床资料,分析低脑氧的发生情况及其对预后的影响。结果纳入患者中有99例发生了低脑氧,在发生低脑氧的患者中,73例患者发生于CPB期间。L组术前血糖水平低于N组,脑钠肽水平高于N组,差异均有统计学意义(P<0.05)。两组术后ICU停留时间、总住院时间、术后急性肾损伤(AKI)发生率、术后最高脑钠肽水平、CPB后最高乳酸水平的差异均有统计学意义(P<0.05)。二分类logistic回归分析显示年龄>65岁(OR=5.557,95%CI:1.660~18.604,P<0.05)和CPB时间>120 min(OR=4.178,95%CI:2.046~8.530,P<0.05)是术中发生低脑氧的危险因素,基础rScO_(2)>60%(OR=0.400,95%CI:0.269~0.962,P<0.05)为发生低脑氧的保护因素。结论心脏瓣膜手术中有一半患者发生低脑氧,多发生于CPB期间。低脑氧可增加AKI发生率、血乳酸水平,延长患者ICU停留时间和总住院时间。

Objective To investigate the incidence of hypoxia in heart valve surgery and its impact on early prognosis.Methods A total of 190 patients who underwent elective heart valve surgery using mild hypothermic extracorporeal circulation(CPB)at West China Hospital of Sichuan University from August 2017 to May 2018 were included.The oxygen saturation(rScO_(2))of bilateral brain tissue was monitored during the operation.A low cerebral oxygen event was defined as rScO_(2)<55%for 5 minutes during the operation.According to the occurrence of hypoxic events,the participants were divided into two groups:the hypoxic group(group L)and the normal cerebral oxygenated group(group N).The clinical data of the two groups were compared,and the incidence of hypoxia and its impact on prognosis were analyzed.Results Hypoxemia occurred in 99 patients,and of those cases,73 cases occurred during CPB.The preoperative blood glucose in the group L was lower than group N,and brain natriuretic peptide was higher than group N(P<0.05).There were statistically significant differences in the following variables between the two groups:postoperative ICU stay time,total hospitalization time,incidence of postoperative acute kidney injury(AKI),brain natriuretic peptide after surgery,and peak lactic acid after CPB(P<0.05).Dichotomous logistic regression analysis showed that being over 65 years old(OR=5.557,95%CI:1.660-18.604,P<0.05)and having a CPB time over 120 minutes(OR=4.178,95%CI:2.046-8.530,P<0.05)were risk factors for intraoperative hypoxia,while having a basic rScO_(2) level above 60%(OR=0.400,95%CI:0.269-0.962,P<0.05)was a protective factor against hypoxia.Conclusion Hypoxia occurs in half of the patients undergoing heart valve surgery,primarily during CPB.Low cerebral oxygen levels can increase the inci dence of AKI,blood lactic acid levels,and prolong the length of stay for patients in ICU and total hospitalization time.