Pv-aCO_(2)在非体外循环冠状动脉旁路移植术后低血容量患者液体复苏中的应用价值

Clinical value of Pv-aCO_(2) in fluid resuscitation of hypovolemic patients after off-pump coronary artery bypass grafting

目的探讨混合静脉-动脉血二氧化碳分压差(Pv-aCO_(2))在非体外循环冠状动脉旁路移植(OPCABG)术后低血容量患者液体复苏中的应用价值。方法选择北部战区总医院2019年5月至2020年8月择期行OPCABG后低血容量冠心病患者120例为研究对象。入ICU后立即给予早期目标导向治疗(EGDT),并2小时记录1次PvaCO_(2),根据术后12小时Pv-aCO_(2)均值分为Pv-aCO_(2)≥6mmHg(高Pv-aCO_(2)组,n=52)和Pv-aCO_(2)<6mmHg(低Pv-aCO_(2)组,n=68)两组。比较两组患者入ICU后0h(T0)、6h(T6)及12h(T12)三个时间点的中心静脉压(CVP)、平均动脉压(MAP)、心脏指数(CI)、乳酸(Lac)和术后机械通气辅助时间、ICU停留时间及并发症。分析Pv-aCO_(2)与CI、Lac的相关性。结果两组患者OPCABG术后T6、T12时CVP、MAP、CI均高于T0时,Lac低于T0时,且低PvaCO_(2)组MAP、CI水平高于高Pv-aCO_(2)组,差异均具有统计学意义(P<0.05)。两组间CVP、Lac比较差异无统计学意义(P>0.05)。低Pv-aCO_(2)组患者机械通气时间、ICU停留时间明显缩短(18.36±5.89hvs 16.07±3.77h,P=0.033;26.22±3.49hvs 22.11±4.58h,P=0.001),术后发生低心排血量综合征、急性肾损伤、呼吸机相关性肺炎及脑梗死并发症的发生率无统计学差异(P>0.05)。T0、T6、T12时Pv-aCO_(2)与CI均呈负相关(r=-0.751、-0.735、-0.742,P<0.01),与Lac均无相关性(r=0.156、0.209、0.185,P=0.125、0.085、0.106)。结论Pv-aCO_(2)有助于判定CI能否作为机体清除外周组织产生的二氧化碳的指标,可指导OPCABG术后患者早期的容量复苏。

Objective To investigate the application value of mixed venous-arterial carbon dioxide partial pressure(Pv-aCO_(2))in fluid resuscitation of hypovolemic patients after off-pump coronary artery bypass grafting(OPCABG).Methods A total of 120hypovolemic patients who were admitted to ICU after elective OPCABG from May 2019to August 2020in the Northern Theater General Hospital were selected as the research objects.Early goal-directed therapy(EGDT)was given immediately after admission to ICU,and Pv-aCO_(2)was recorded once every 2hours.According to the average value of Pv-aCO_(2)at 12hours after surgery,the patients were divided into Pv-aCO_(2)≥6mmHg group(high Pv-aCO_(2)group,n=52)and Pv-aCO_(2)<6mmHg group(low Pv-aCO_(2)group,n=68).The central venous pressure(CVP),mean arterial pressure(MAP),cardiac index(CI)and lactate(Lac)at 0h(T0),6h(T6)and 12h(T12)of ICU admission and postoperative mechanical ventilation time,ICU stay time,complications were compared between the two groups.Analyze the correlation between Pv-aCO_(2)and CI,Lac.Results The CVP,MAP,HR,and CI at T6and T12in the two groups after OPCABG were higher than those at T0,Lac was lower than that at T0,and the levels of MAP and CI in the low Pv-aCO_(2)group were better than those in the high Pv-aCO_(2)group(all P<0.05).There was no significant difference in CVP and Lac between the two groups(P>0.05).Compared with the high Pv-aCO_(2)group,the mechanical ventilation time and ICU stay time in the low Pv-aCO_(2)group were significantly shortened(18.36±5.89hvs 16.07±3.77h,P=0.033;26.22±3.49hvs 22.11±4.58h,P=0.001)and the incidence of postoperative complications in low cardiac output syndrome,acute kidney injury,ventilator-associated pneumonia and cerebral infarction was not significant difference(P>0.05).Pv-aCO_(2) was negatively correlated with CI at T0,T6,and T12(r=-0.751,-0.735,-0.742,P<0.01),but not with Lac(r=0.156,0.209,0.185,P=0.125,0.085,0.106).Conclusion Pv-aCO_(2)can help determine whether CI is sufficient to remove carbon dioxide produced by the peripheral tissues of the body and guide the early volume resuscitation of patients after OPCABG.