Prevalence and Potential Impact of Gastrointestinal Insufflation During Cardiopulmonary Resuscitation

<b>Background/Objectives:</b> Insufflation of the gastrointestinal tract, as a side effect of improper ventilation, is a known complication in resuscitation patients. As animal studies have shown, this can be associated with an increase in intra-abdominal pressure with adverse effects on hemodynamics and respiratory mechanics. In this study, we investigated the prevalence and severity of insufflation and discussed the potential impact on the outcome of resuscitation. <b>Methods:</b> This study was based on computed tomography (CT) images from two university hospitals in Munich, Germany, which were taken as part of the trauma room care of out-of-hospital cardiac arrest (OHCA) patients. According to local resuscitation protocol, CT performed during ongoing cardiopulmonary resuscitation or after the return of spontaneous circulation (ROSC) was archived to determine the potentially reversible cause of cardiac arrest. CT images from 2014 to 2018 were analyzed in this study. Using an advanced visualization and analysis platform for medical image data, the gas volume within the gastrointestinal tract was determined and compared between resuscitations with lethal and secondary survival outcomes. <b>Results:</b> A total of 92.44% of included OHCA patients (<i>n</i> = 172) showed signs of increased gastrointestinal gas volume in comparison to the physiologically prevalent gas volume. In OHCA patients with a lethal outcome, significantly more gas was detected in the gastrointestinal tract with a median of 757.40 mL compared to 380.65 mL in resuscitations with secondary survival (<i>p</i> ≤ 0.05; W = 4278). Furthermore, Cohen's r was used to calculate the effect size, indicating a weak association with the outcome of resuscitation (r = 0.24). In addition, a logistic regression analysis was performed to examine the influence of age, gender (female), and the gas volume of the intestines and stomach on the dependent variable "death". The analysis shows that the model, as a whole, is significant (Chi² = 17.67; <i>p</i> 0.02; <i>n</i> = 172) and supports the hypothesis that intestinal insufflation correlates with a lethal outcome from resuscitation (b = 0.001; OR 1.001 (95% CI [1.000-1.002]; <i>p</i> = 0.021). <b>Conclusions:</b> Insufflation in resuscitation patients is a common phenomenon with potential consequences for the outcome. Even if the effect we have shown appears small, the outcome of resuscitation patients can possibly be improved by preventing or correcting insufflation. To understand its potential impact on resuscitation outcomes fully, further work must be performed to investigate causality.