Clinical research on predicting outcome of difficult-to-wean by central venous oxygen saturation

WANG Wei-jie; XU Lei; FENG Quan-sheng; GAO Xin-jing; LI Zhi-bo; SUN Li-xiao

doi:10.3969/j.issn.1002-266X.2014.20.004

Abstract：Objective To evaluate the value of central venous oxygen saturation ( ScvO2 ) in predicting weaning out-come in difficult-to-wean patients .Methods Totally 184 patients took 214 cases of weaning .According to the weaning re-sults, they were divided into the weaning success group and weaning failure group , and also were stratified as cardiac dys-function group and non-cardiac dysfunction group .The ScvO2 at the moment of disconnecting the ventilator and at the 30th min of spontaneous breathing trial (SBT) and their difference of ΔScvO2 were observed, meanwhile, the relationship be-tween these three parameters and weaning outcome were analyzed in this study .Results The ScvO2 of SBT and ΔScvO2 of the 214 cases at the 30th min in the weaning success group and weaning failure group were respectively 74.6%±6.6%, 2.76 ±4.16 and 71.4%±5.5%, 4.63 ±3.71, (all P<0.05).The cut off value of ΔScvO2 in predicting weaning failure was 3.65%, the sensitivity was 73.3%and the specificity was 60.3%.Stratified analysis showed that:among the cardiac dysfunction patients , the ScvO2 of SBT and ΔScvO2 at the 30th min were 73.6%±5.2%and 2.61 ±3.13 in the weaning success group, while 70.4%±5.2%and 5.08 ±2.38 in the weaning failure group (P<0.05 or P<0.01).The cut off value ofΔScvO2 in predicting weaning failure of the cardiac dysfunction patients was 4.0%, the sensitivity was 85.0%and the specificity was 73.6%, but no difference was found in the non-cardiac dysfunction group .Conclusions The ScvO2 of SBT and ΔScvO2 at the 30 th min could predict weaning outcome of difficult-to-wean patients, and ΔScvO2≥4.0% could be regarded as a predictive factor of weaning failure in patients with cardiac dysfunction .