Factors influencing resuscitation outcomes in obese out-of-hospital cardiac arrest patients

Given limited prehospital emergency human resources, emergency transfer of obese out-of-hospital cardiac arrest (OHCA) patients is often associated with great difficulties. This study aims to identify and weigh factors influencing outcomes of emergency transfer in obese OHCA patients.

We conducted a retrospective analysis of 172 OHCA patients treated by emergency medical services (EMS). Spearman correlation analysis was used to examine the correlation between factors. Least absolute shrinkage and selection operator (LASSO) regression was employed to screen for significant factors. A multifactorial logistic risk regression model was then established. The influencing factors were evaluated using an odds ratio (OR) forest plot, and the predictive efficacy of the model was assessed using a working curve.

After conducting Spearman correlation analysis and LASSO regression screening, body mass index (BMI), age, cardiopulmonary resuscitation (CPR) grade, timely detection and defibrillation, and bystander CPR duration were found to be correlated with return of spontaneous circulation (ROSC). Logistic regression analysis indicated that obese OHCA patients with a BMI above 22.5 have a 9.25 times higher risk (95% confidence interval [CI] 1.23–82.13, p = 0.009) than those without obesity. Similarly, individuals above the age of 35 faced a 7.67 times higher risk (95%CI 1.07–98.4, p = 0.043) compared to those aged 35 or below. Additionally, the risk of low-quality CPR was 16.45 times higher (95%CI 2.45–207.39, p = 0.009) than high-quality CPR. Failing to defibrillate in a timely manner resulted in 8.15 times higher risk (95%CI 1.24–76.23, p = 0.036) compared to timely detection and defibrillation. Moreover, having a bystander CPR time exceeding 10 min carried a 2.36 times higher risk (95%CI 0.20–28.67, p = 0.047) compared to a bystander CPR time of 10 min or less. The logistic regression indicated a high predictive efficacy of the model.

The ROSC rate of obese patient after OHCA is much lower compared to that of nonobese patients. It is crucial to prioritize high-quality CPR especially during the transfer of obese OHCA patients.