Outcome and adverse events with 72-hour cooling at 32°C as compared to 24-hour cooling at 33°C in comatose asphyxial arrest survivors

Abstract

Purpose: Studies suggest that the current therapeutic hypothermia (TH) protocol does not improve outcomes in adult asphyxial arrest survivors. We sought to compare the effect of 24-hour cooling at 33°C vs that of 72-hour cooling at 32°C on outcomes and the incidence of adverse events in unconscious asphyxial arrest survivors.

Methods: Retrospectively collected data on 79 consecutive asphyxial arrest patients treated with TH from January 2006 to March 2013 were analyzed. Forty-one patients who presented between January 2006 and January 2011 formed the 33°C-24 h group, whereas 38 patients who presented between February 2011 and March 2013 formed the 32°C-72 h group. The primary outcome was neurologic outcome at 30 days following arrest. The secondary outcomes were all-cause mortality at 30 days following arrest and the incidence of adverse events.

Results: The Kaplan-Meier curve showed no significant difference in survival over time during the 30 days after arrest between the 2 groups (P = .608). Good neurologic outcome was achieved in only 2 patients (2.5%) of the overall cohort, despite TH. One of the 32°C-72 h group (2.6%; 95% confidence interval, 4.7%-13.5%) had a good neurologic outcome, as did one of the 33°C-24 h group (2.4%; 95% confidence interval, 4.3%-12.6%) (P = 1.000). There were no significant differences in the rates of adverse events between the 2 groups.

Conclusion: The present study did not demonstrate an advantage of 72-hour cooling at 32°C in unconscious asphyxial arrest patients compared with 24-hour cooling at 33°C.