Induced hypothermia after out-of-hospital cardiac arrest: one hospital's experience.
OBJECTIVE
Induced mild hypothermia has been shown to reduce in-hospital mortality and to improve neurological outcome in patients who remain comatose after out-ofhospital cardiac arrest (OHCA). We conducted a retrospective audit to assess whether induced hypothermia had been successfully incorporated into routine care at our hospital, and whether this improved patient outcomes.


METHODS
Retrospective audit of patients admitted to a Level III intensive care unit, Melbourne, Victoria, between 2001 and 2007. Patients treated with therapeutic hypothermia (introduced in 2004) were compared with those who did not receive this therapy.


METHODS
Patients admitted to the ICU comatose after OHCA with a presumed cardiac cause.


METHODS
Induction of mild hypothermia by rapid infusion of cold intravenous fluids.


METHODS
Hospital survival and neurological outcome at hospital discharge; time taken for core temperature to reach the target range (33 degrees +/-0.5 degrees C) and time temperature was maintained, determined from patient ICU records.


RESULTS
123 patients were admitted comatose after OHCA with a presumed cardiac cause: 75 were admitted after induced hypothermia was introduced into routine care and received this treatment; and 48 admitted earlier did not receive the treatment. For patients with the initial rhythm of ventricular fibrillation (VF) or unstable ventricular tachycardia (uVT), treatment with induced hypothermia was associated with a higher hospital survival rate (P=0.03; odds ratio [OR], 2.51; 95% CI, 1.06-5.95) and better neurological outcome (P=0.02; OR, 2.85; 95% CI, 1.19-6.86). In 90% of patients treated with induced hypothermia, core temperature reached the target range within 6 hours of hospital presentation; mean duration of in-hospital cooling was 25.5 hours (SD, 2.9 hours).


CONCLUSIONS
We found that induced hypothermia can be incorporated into routine care of patients admitted to an ICU after OHCA. For patients with an initial rhythm of VF or uVT, this seems to have significantly improved hospital survival and neurological outcome. We also found that rapid infusion of cold intravenous fluids was effective for inducing hypothermia.
Whitfield
Ann M
AM
Intensive Care Unit, Box Hill Hospital, Melbourne, VIC. Ann.Whitfield@easternhealth.org.au
Coote
Skye
S
Ernest
David
D
D000368:Aged; D000369:Aged, 80 and over; D006323:Heart Arrest / Q000401:mortality* / Q000628:therapy*; D006784:Hospitals, Teaching; D006801:Humans; D007036:Hypothermia, Induced; D007362:Intensive Care Units; D008485:Medical Audit; D008875:Middle Aged; D012189:Retrospective Studies; D015996:Survival Rate; D017180:Tachycardia, Ventricular / Q000453:epidemiology; D014693:Ventricular Fibrillation / Q000453:epidemiology; D014739:Victoria / Q000453:epidemiology