Effects of pre-hospital re-arrest on outcomes based on transfer to a heart attack centre in patients with out-of-hospital cardiac arrest

Aim: We aimed to investigate the interaction effects between transfer to a heart attack centre [HAC] and prehospital re-arrest on the clinical outcomes of patients with out-of-hospital cardiac arrest [OHCA].

Methods: We included adult patients with OHCA of presumed cardiac aetiology from January 2012 to December 2018. The main exposure variable was prehospital re-arrest, defined as recurrence of cardiac arrest with a loss of palpable pulse upon hospital arrival. The other exposure variable was the resuscitation capacity of the receiving hospital [HAC or Non-HAC]. The outcome variable was neurological recovery. A multivariable logistic regression was performed to determine the interaction effects.

Results: The final analysis included 6935 patients. Of these, 21.9% (n = 1521) experienced prehospital re-arrest, whereas 41.3% (n = 2866) were transferred to a non-HAC. The prehospital re-arrest group associated with poor neurological recovery (adjusted odds ratio [AOR], 0.25; 95% confidence interval [CI], 0.21-0.29;). Transfer to an HAC had beneficial effects on neurological recovery (AOR, 3.40 [95% CI, 3.04-3.85]. In the interaction model, wherein prehospital re-arrest patients who were transferred to a non-HAC were used as reference, the AOR of prehospital re-arrest patients who were transferred to an HAC, non-re-arrest patients who were transferred to a non-HAC, and non-re-arrest patients who were transferred to a non-HAC was 2.41 (95% CI, 1.73-3.35), 3.09 (95% CI, 2.33-4.10), and 11.07 (95% CI, 8.40-14.59) respectively (interaction p = 0.001).

Conclusion: Transport to a heart attack centre was beneficial to the clinical outcomes of patients who achieved prehospital ROSC after OHCA. The magnitude of that benefit was significantly modified by whether prehospital re-arrest had occurred.