Sex-Specific Outcomes of Patients Treated With Extracorporeal Cardiopulmonary Resuscitation

Patients after cardiac arrest (CA) treated with extracorporeal cardiopulmonary resuscitation (eCPR) evidence high mortality. Recently, women were reported to evidence even worse outcomes after CA. However, sex-specific data on CA patients treated with eCPR are lacking. We therefore aimed to evaluate potential sex differences in risk distribution, management, and outcomes in patients treated with eCPR.

Sixty-four patients - 16 females (25%) and 48 males (75%) - were included in this retrospective analysis. Two propensity scores were calculated on sex using multivariable logistic regression. Propensity score 1 included baseline characteristics only, and propensity score 2 included the previous variables plus pH as well as lactate concentration. Univariable and multivariable logistic regression models were used to assess associations with the endpoints.

The distribution of risk factors and baseline characteristics showed no sex-specific differences. Sex was neither associated with mortality nor with bad neurological outcomes, and remained so after adjustment for both propensity scores. Baseline lactate (adjust odds ratio [aOR], 1.18; 95% confidence interval [CI], 1.02-1.38; P=.03), lactate after 6 hours (aOR, 1.23; 95% CI, 1.04-1.45; P=.01), and lactate clearance at 6 hours (aOR, 0.979; 95% CI, 0.959-0.999; P=.04) were independently associated with 30-day mortality. Higher lactate clearance after 6 hours was associated with lower rates of bad Glasgow Outcomes Scale both in univariable (OR, 0.967; 95% CI, 0.941-0.991; P=.02) and multivariable logistic regression models (aOR, 0.967; 95% CI, 0.941-0.994; P=.02).

There were no sex-specific outcome differences in patients treated with eCPR. Both lactate concentration and lactate clearance could help with the selection of patients for inclusion in eCPR trials.