To intubate or not to intubate?:

Duration of exposure to a prehospital advanced airway and neurological outcome for out-of-hospital cardiac arrest: A retrospective cohort study

BACKGROUND

Out-of-hospital cardiac arrest (OHCA) studies have focused on the benefits and harms of placing an intra-arrest advanced airway, but few studies have evaluated the benefits and harms after successful placement. We hypothesize that increased time in the tumultuous prehospital environment after intra-arrest advanced airway placement results in reduced patient survival.

METHODS

This was a secondary analysis of adult, non-traumatic, OHCA patients with an advanced airway placed in the PRIMED trial. The exposure variable was the time interval between successful advanced airway placement and Emergency Department (ED) arrival. The outcome was cerebral performance category (CPC) 1 or 2 at hospital discharge. Multivariable logistic regression, adjusted for Utstein variables and resuscitation-associated time intervals, was used to estimate adjusted odds ratios (aOR).

RESULTS

The cohort of complete cases included 4779 patients. The median time exposed to a prehospital advanced airway was 27 min (IQR 20-35). The total prehospital time was 39.4 min (IQR 32.3-48.1). An advanced airway was placed intra-arrest in 3830 cases (80.1%) and post-return of spontaneous circulation (post-ROSC) in 949 cases (19.9%). Overall, 486 (10.2%) of the cohort achieved the CPC outcome, but this was higher in the post-ROSC (21.7%) versus intra-arrest (7.5%) cohort. CPC was not associated with the time interval from advanced airway placement to ED arrival in the intra-arrest airway cohort (aOR 0.98, 95%CI 0.94-1.01).

CONCLUSIONS

In OHCA patients who receive an intra-arrest advanced airway, longer time intervals exposed to a prehospital advanced airway are not associated with reduced patient survival.

Effects of Bag Mask Ventilation and Advanced Airway Management on Adherence to Ventilation Recommendations and Chest Compression Fraction: A Prospective Randomized Simulator-Based Trial

The role of advanced airway management (AAM) in cardiopulmonary resuscitation (CPR) is currently debated as observational studies reported better outcomes after bag-mask ventilation (BMV), and the only prospective randomized trial was inconclusive. Adherence to CPR guidelines ventilation recommendations is unknown and difficult to assess in clinical trials. This study compared AAM and BMV with regard to adherence to ventilation recommendations and chest compression fractions in simulated cardiac arrests. A total of 154 teams of 3–4 physicians were randomized to perform CPR with resuscitation equipment restricting airway management to BMV only or equipment allowing for all forms of AAM. BMV teams ventilated 6 ± 6/min and AAM teams 19 ± 8/min (range 3–42/min; p < 0.0001 vs. BMV). 68/78 BMV teams and 23/71 AAM teams adhered to the ventilation recommendations (p < 0.0001). BMV teams had lower compression fractions than AAM teams (78 ± 7% vs. 86 ± 6%, p < 0.0001) resulting entirely from higher no-flow times for ventilation (9 ± 4% vs. 3 ± 3 %; p < 0.0001). Compared to BMV, AAM leads to significant hyperventilation and lower adherence to ventilation recommendations but favourable compression fractions. The cumulative effect of deviations from ventilation recommendations has the potential to blur findings in clinical trials.