Effect of stomach inflation during cardiopulmonary resuscitation on return of spontaneous circulation in out-of-hospital cardiac arrest patients: A retrospective observational study

Background: Gastric inflation caused by excessive ventilation is a common complication of cardiopulmonary resuscitation. Gastric inflation may further compromise ventilation via increases in intrathoracic pressure, leading to decreased venous return and cardiac output, which may impair out-of-hospital cardiac arrest (OHCA) outcomes. The purpose of this study was to measure the gastric volume of OHCA patients using computed tomography (CT) scan images and evaluate the effect of gastric inflation on return of spontaneous circulation (ROSC).Methods: In this single-center, retrospective, observational study, CT scan was conducted after ROSC or immediately after death. Total gastric volume was measured. Primary outcome was ROSC. Achievement of ROSC was compared in the gastric distention group and the no gastric dis-tention group; gastric distension was defined as total gastric volume in the >= 75th percentile. Additionally, factors associated with gastric distention were examined.Results: A total of 446 cases were enrolled in the study; 120 cases (27%) achieved ROSC. The median gastric volume was 400 ml for all OHCA subjects; 1068 ml in gastric distention group vs. 287 ml in no gastric distention group. There was no difference in ROSC between the groups (27/112 [24.1%] vs. 93/334 [27.8%], p = 0.440). Gastric distention did not have a significant impact, even after adjustments (adjusted odds ratio 0.73, 95% confidence interval [0.42-1.29]). Increased gastric volume was associated with longer emergency medical service activity time.Conclusions: We observed a median gastric volume of 400 ml in patients after OHCA resuscitation. In our setting, gastric distention did not prevent ROSC.