Predictors of death among cardiac arrest patients after therapeutic hypothermia: A non-tertiary care center's initial experience

Abstract

Introduction and objectives: Therapeutic hypothermia (TH) is recommended for patients with return of spontaneous circulation (ROSC) after cardiac arrest (CA). There is still uncertainty about management, target temperature and duration of TH. In the present study we aim to describe the initial experience of a non-tertiary care center with TH after CA and to determine predictors of mortality.

Methods: During the period 2011-2014, out of 2279 patients hospitalized in the intensive care unit, 82 had a diagnosis of CA with ROSC. We determined predictors of mortality and neurological outcome in comatose patients with ROSC after CA treated by TH.

Results: A total of 15 patients were included, mean age 47.3±14 years, 10 (67.0%) male. CA occurred out-of-hospital (n=11; 73.3%) or in-hospital (n=4; 26.7%), in initial shockable (n=10; 66.7%) or non-shockable (n=5, 33.3%) rhythm. The mean time from CA to ROSC (CA-ROSC) was 44.7±36.5 min. All patients met the 24-hour TH target temperature of 33°C. The mean neuron-specific enolase (NSE) level was 93.7±109.0 μg/l. Seven patients (46.7%) were discharged with good cerebral performance and eight (53.3%) died. Patients who survived had lower median age (p=0.032), shorter CA-ROSC (p=0.048), lower NSE levels (p=0.020) and initial ventricular fibrillation rhythm (p=NS).

Conclusions: The effectiveness of TH appears to be related to younger age, shockable initial rhythm and shorter CA-ROSC time. This results indicates some lines of inquiry that should be developed in appropriate prospective studies. The role of biomarkers as predictors of prognosis is an open question, with NSE potentially playing an important role.

Keywords: Cardiac arrest; Enolase específica dos neurónios; Hipotermia terapêutica; Neuron-specific enolase; Paragem cardíaca; Therapeutic hypothermia.