2012-Nov – CCM Exit Exam Dissertation Abstract: Therapeutic Hypothermia after Cardiac Arrest – A Survey of Practice in ICUs in Hong Kong

Dr Alwin WT Yeung, ICU, Pamela Youde Nethersole Eastern Hospital, Hong Kong

Background

Previous studies showed that therapeutic hypothermia after out-of-hospital ventricular fibrillation arrest significantly improved neurological outcome and survival. This retrospective case series aims to examine the practice of therapeutic hypothermia in resuscitated post cardiac arrest patients in Hong Kong.

Methods

Post cardiac arrest patients with therapeutic hypothermia in eight local ICUs from January 2007 to June 2012 were identified. Baseline demographic characteristics, clinical data on the cardiac arrest, cooling profile and patient outcomes were recorded. Statistical analyses were performed to identify factors associated with good neurological outcome at hospital discharge.

Results

124 patients underwent therapeutic hypothermia within the aforesaid time period. Majority was out-of-hospital arrest (73.4%) and male (71.8%). The median age was 59. The initial presenting cardiac rhythm was shockable in 58.1%. 33.3% of the patients enjoyed good neurological outcome. The hospital mortality was 48.4%. The median cooling rate and time from ROSC to target temperature were 0.48°C/hour and 7 hours respectively. The median actual duration of mild hypothermia was 16.5 hours. Multivariate logistic regression analysis revealed that an older age, a longer downtime and a higher blood glucose range during therapeutic hypothermia had a reduced odds ratio for good neurological outcome while a shockable presenting rhythm was the strongest independent predictor for good neurological outcome (OR 38.54, 95% CI 6.07-244.48, p<0.001).

Conclusions

Therapeutic hypothermia is probably underutilized in Hong Kong. It is most beneficial for patients with an initial shockable rhythm. More studies are to be done to identify optimal ways to attain rapid cooling and maintain hypothermia.

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