Comparative evaluation of the usability of 2 different methods to perform mild hypothermia in patients with out-of-hospital cardiac arrest.
BACKGROUND
Several studies have shown that mild hypothermia (32-34°C) markedly mitigates brain damage after cardiac arrest (CA). This study aimed to compare the efficacy of the non-invasive cooling device Hilotherm Clinic (Hilotherm GmbH, Germany) with conventional cooling to induce and maintain mild hypothermia in patients after out-of-hospital CA.


METHODS
50 adult patients with an indication for controlled mild hypothermia were prospectively assigned to conventional cooling (n=20) or cooling with the Hilotherm system (n=30). Patients receiving a cooling therapy by Hilotherm were treated either with 0.35 m(2) (n=20) or with 0.7 m(2) (n=10) surface area of cooling sleeves.


RESULTS
The speed of cooling was significantly higher in both Hilotherm groups compared to conventional cooling (Hilotherm 0.7 m(2): 0.91 ± 0.08°C/h, Hilotherm 0.35 m(2): 0.47 ± 0.04°C/h, and conventional: 0.3 ± 0.04°C/h, p ≤ 0.003). Temperature deviation from the target temperature of 33°C was significantly higher in the conventional group compared to both Hilotherm groups. During induction of mild hypothermia a significant reduction of the mean arterial blood pressure and the heart rate was observed without significant differences between the groups. However, the speed of cooling (range 0.3-0.91°C/h) did not correlate to the decrease of blood pressure and heart rate. Norepinephrine dosing during induction of mild hypothermia and re-warming (1st-2nd day) was significantly increased compared to the 3rd day after admission in all groups. Dobutamine dosing and 30 days in-hospital mortality did not differ significantly between the groups.


CONCLUSIONS
Rapid and reliable mild hypothermia can be better achieved by the non-invasive cooling system Hilotherm compared to conventional cooling with ice packs and cold infusion.
Rana
Majeed
M
Department of Oral and Maxillofacial Surgery, Medical School Hannover, Hannover, Germany. rana.majeed@mh-hannover.de
W Schröder
Jörg
J
Saygili
Erol
E
Hameed
Umer
U
Benke
Dirk
D
Hoffmann
Rainer
R
Schauerte
Patrick
P
Marx
Nikolaus
N
Rana
Obaida R
OR
D001794:Blood Pressure / Q000502:physiology; D005260:Female; D006339:Heart Rate / Q000502:physiology; D017052:Hospital Mortality / Q000639:trends; D006801:Humans; D007036:Hypothermia, Induced / Q000379:methods*; D008297:Male; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000401:mortality / Q000503:physiopathology* / Q000628:therapy*