Tacheal intubation vs. supraglottic airway devices during mechanical intra-arrest-ventilation with volume-controlled-ventilation in out-of-hospital cardiac arrest: a cohort study

Comprehensive Summary

Eickelmann et al. conducted a retrospective cohort study comparing supraglottic airway devices (SGA) versus tracheal intubation (TI) for ventilation effectiveness during mechanical intra-arrest resuscitation in adult out-of-hospital cardiac arrest (OHCA). Real-world ventilation data from emergency ventilators used by EMS in the Gütersloh district of Germany were linked with patient data from the German Resuscitation Registry (January 2019 to August 2023). All patients received volume-controlled ventilation (VCV) during intra-arrest care. The primary outcome was the difference between set tidal volume (VTset) and measured expiratory tidal volume (VTe), with leakage volume (VLeak) as a secondary outcome. Among 27 patients receiving intra-arrest VCV, TI demonstrated significantly smaller deviation between VTset and VTe and substantially lower leakage compared to SGA in adjusted analyses controlling for age, sex, and cardiac arrest etiology.

Outcomes and Implications

Optimal airway management during OHCA remains highly controversial, with ongoing debate about whether advanced airways improve outcomes or simply interrupt critical chest compressions. Recent large trials have suggested supraglottic airways may be non-inferior or even superior to tracheal intubation for overall survival, potentially due to faster placement and fewer compression interruptions. This study contributes physiologic data to this debate by demonstrating that tracheal intubation delivers more accurate tidal volumes with less air leakage compared to SGAs during volume-controlled mechanical ventilation. However, the clinical significance of these physiologic differences remains uncertain. Better ventilation effectiveness does not necessarily translate to improved survival, particularly if achieving TI requires prolonged intubation attempts that interrupt chest compressions, which are the most critical determinant of OHCA survival. The study's major limitation is its very small sample size of only 27 patients, which substantially limits the precision and generalizability of findings. The single-center design in one German EMS system may not reflect practices or outcomes elsewhere. Critically, the study provides no data on patient outcomes such as return of spontaneous circulation or survival, making it impossible to know whether the observed physiologic advantages of TI matter clinically. The study also cannot account for important confounders such as the time required to achieve airway placement, number of intubation attempts, interruptions in chest compressions, or provider skill level, all of which influence real-world airway management decisions. Additionally, the reasons why patients received TI versus SGA were not standardized and may reflect selection bias, with providers choosing TI for cases where they anticipated better conditions for intubation. For prehospital providers, these findings suggest that when TI can be achieved rapidly and without significant compression interruptions, it may provide superior ventilation quality. However, given the small sample size and lack of outcome data, this study alone should not change current practice patterns that prioritize minimizing compression interruptions. Future research should examine whether TI-associated improvements in ventilation effectiveness translate to better neurologic outcomes in adequately powered randomized trials that measure time to airway placement, compression interruptions, and patient-centered outcomes. Until such data exist, airway management strategies should continue to prioritize high-quality chest compressions and minimize interruptions, with device selection based on provider experience and first-pass success likelihood.