Risk Factors for Agitation and Hyperactive Delirium in Adult Postcardiotomy Patients with Extracorporeal Membrane Oxygenation Support: an Observational Study

Agitation and delirium in critically ill patients after cardiac surgery carry poor in-hospital prognosis. Identifying risk factors may promote its prevention and management. Accordingly, this study aimed to evaluate the incidence of agitation and hyperactive delirium in postcardiotomy patients during the extracorporeal membrane oxygenation support and to identify the risk factors for its development.

This single center, retrospective study was conducted at Beijing Anzhen Hospital, Capital Medical University. Data were extracted from the prospective institutional registry database of extracorporeal membrane oxygenation patients. Univariate and multivariate logistic regression analyses were performed to predict risk factors.

A total of 170 consecutive adult patients underwent extracorporeal membrane oxygenation in our hospital from January 2016 to December 2017. Ninety-four patients were included in the final analysis. The incidence of agitation and hyperactive delirium was 35% in our population of extracorporeal membrane oxygenation–supported postcardiotomy patients. Agitation and delirium usually occurred within the first 3 days of extracorporeal membrane oxygenation. Multivariable analysis showed that history of previous stroke (without preoperative cognitive dysfunction; odds ratio, 4.425, 95% confidence interval: 1.171-16.716; p = 0.028) and mean arterial pressure reduction (before extracorporeal membrane oxygenation initiation) ⩾ 49 mmHg (odds ratio, 7.570, 95% confidence interval: 2.366-24.219, p = 0.001) were independent risk factors for agitation and hyperactive delirium during extracorporeal membrane oxygenation support. The areas under the receiver operating characteristic curve for the prediction of agitation and hyperactive delirium was 0.704 (95% confidence interval 0.589-0.820, p = 0.001). There was more severe arrhythmia in the agitation patients.

Our results suggest that the prevalence of agitation and hyperactive delirium in postcardiotomy patients with extracorporeal membrane oxygenation support is high. In addition, previous stroke and severe mean arterial pressure reduction before extracorporeal membrane oxygenation initiation is predictive of agitation and hyperactive delirium.