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 six 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: 117 patients underwent therapeutic hypothermia within the aforementioned time period. Majority was out-of-hospital arrest (75.2%) and male (70.1%). The median age was 59. The initial presenting cardiac rhythm was shockable in 59.0%. Thirty-two point two percents of the patients enjoyed good neurological outcome. The hospital mortality was 49.6%. The median cooling rate and time from regain of spontaneous circulation (ROSC) to target temperature were 0.50°C/hour and 6.5 hours respectively. 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 34.25, 95% CI 5.30-221.22, p<0.001).
Conclusions: Therapeutic hypothermia is probably underutilized in Hong Kong. It is most beneficial for patients with an initial shockable rhythm. In future practice, more attention should be paid in attaining rapid cooling, maintaining tight temperature and glucose control.