Long term outcomes of participants in the PARAMEDIC2 randomised trial of adrenaline in out-of-hospital cardiac arrest

Aims: We recently reported early outcomes in patients enrolled in a randomised trial of adrenaline in out-of-hospital cardiac arrest: the PARAMEDIC2 (Prehospital Assessment of the Role of Adrenaline: Measuring the Effectiveness of Drug Administration in Cardiac Arrest) trial. The purpose of the present paper is to report long-term survival, quality of life, functional and cognitive outcomes at 3, 6 and 12-months.

Methods: PARAMEDIC2 was a pragmatic, individually randomised, double blind, controlled trial with an economic evaluation. Patients were randomised to either adrenaline or placebo. This paper reports results on the modified Rankin Scale scores at 6-months, survival at 6 and 12-months, as well as other cognitive, functional and quality of life outcomes collected at 3 and 6 months (Two Simple Questions, the Mini Mental State Examination, the Informant Questionnaire on Cognitive Decline Evaluation for Cardiac Arrest, Hospital Anxiety and Depression Scale, the Post Traumatic Stress Disorder Checklist - Civilian Version, Short-Form 12-item Health Survey and the EuroQoL EQ-5D-5L).

Results: 8014 patients were randomised with confirmed trial drug administration. At 6-months, 78 (2.0%) of the patients in the adrenaline group and 58 (1.5%) of patients in the placebo group had a favourable neurological outcome (adjusted odds ratio 1.35 [95% confidence interval: 0.93, 1.97]). 117 (2.9%) patients were alive at 6-months in the adrenaline group compared with 86 (2.2%) in the placebo group (1.43 [1.05, 1.96], reducing to 107 (2.7%) and 80 (2.0%) respectively at 12-months (1.38 [1.00, 1.92]). Measures of 3 and 6-month cognitive, functional and quality of life outcomes were reduced, but there was no strong evidence of differences between groups.

Conclusion: Adrenaline improved survival through to 12-months follow-up. The study did not find evidence of improvements in favourable neurological outcomes. (ISCRTN 73485024).