Abstract 18031: Effects of Rapid Intravenous Ice-Cold Fluids for Patients Treated with Therapeutic Hypothermia

Abstract

BACKGROUND Animal data has demonstrated that the sooner cooling is initiated after return of spontaneous circulation (ROSC) from cardiac arrest (CA), the better the outcome. Although rapid infusion of ice-cold intravenous (IV) fluids is feasible, safe, and simple method for induction of hypothermia, it is unclear whether technique of ice-cold IV fluids for induction of hypothermia can increase neurological benefit in patients with ROSC after out-of-hospital CA due to shockable rhythm and non-shockable rhythm. METHODS The J-PULSE-Hypo was conducted a multi-center observational registry to investigate the effects of therapeutic hypothermia. In this study, we investigated the effects of ice-cold IV fluids in patients divided into initial CA rhythm (shockable rhythm and non-shockable rhythm). The primary endpoint was favorable neurological outcome at hospital discharge. RESULTS Of the 452 unconscious adult patients who were treated with therapeutic hypothermia after out-of-hospital CA due to cardiac etiology, 435 who were cooled from 32°C to 34°C using external devices or extracorporeal devices were included; 228 received induction of cooling using rapid infusion of ice-cold IV fluids, including 185 shockable CA and 43 non-shockable CA, and 215 did not receive ice-cold IV fluids, including 156 shockable CA and 59 non-shockable CA. The time interval from ROSC to induction of cooling was shorter in the IV group than in the non-IV group in each CA rhythm (median; 28 minutes vs. 133 minutes in the shockable CA, p<0.0001, 21 minutes vs. 81 min in the non-shockable CA, p<0.0001). The IV group had higher frequency of favorable neurological outcome than the non-IV group in the patients with shockable CA (68.6% vs.57.7%, p=0.036), but the two groups had similar frequency of favorable neurological outcome in the patients with non-shockable CA. Adjusted odds ratios for favorable neurological outcome after the IV group was 1.66 (95% CI, 1.04-2.65) in the patients with shockable CA, and 0.53 (95% CI, 0.20-1.40) in the patients with non-shockable CA. CONCLUSION Rapid infusion of ice-cold IV fluids for induction of hypothermia had neurological benefit for patients with shockable CA, but it had not neurological benefit for patients with non-shockable CA.