Impact of hypotension after return of spontaneous circulation on survival in patients of out-of-hospital cardiac arrest.

OBJECTIVE

To investigate the relationship between hypotension in the first 3h after return of spontaneous circulation (ROSC) in patients with out-of-hospital cardiac arrest.

METHOD

This retrospective cohort study occurred at two regional hospitals and included adult OHCA patients who experienced ROSC from July 1, 2014 to December 31, 2015. Hemodynamic and inotrope administration data were retrieved for 3h after ROSC. We calculated the hypotensive exposure index (HEI) as the surrogate marker of the exposure of hypotension. The area under the ROC curve and multivariate logistic regression models were performed to analyze the effect of HEI on survival. Mean arterial pressure (MAP) was explored in the surviving and non-surviving patient groups using repeated measures MANCOVA, adjusted for the use of inotropes and down time.

RESULTS

A total of 289 patients were included in the study, and 29 survived. The median 1-hour HEI and 3-hour HEI were significantly lower in the survival group (p<0.001). The area under the ROC curve for 3-hour HEI was 0.861. The repeated measures MANCOVA indicated that an interaction existed between post-ROSC time and downtime [F(5,197)=2.31, p=0.046]. No significant change in the MAP was observed in the 3h after ROSC, except in the group with a prolonged down time. According to the tests examining the effects of the use of inotropes on the survival outcomes of the different subjects, the MAP was significantly higher in the surviving group [F(1,201)=4.11; p=0.044; ηp2=0.020].

CONCLUSION

Among the patients who experienced ROSC after OHCA, post-ROSC hypotension was an independent predictor of survival.