Therapeutic hypothermia (TH) is a commonly applied therapy for comatose patients who are hospitalized following out-of-hospital cardiac arrest (OHCA).
We hypothesized that rates of TH at individual hospitals are proportional to the annual volume of patients hospitalized following OHCA.
This was a retrospective chart review of patients with OHCA admitted to 21 medical centers between 2007 and 2011. A standardized clinical protocol and educational program promoting the use of TH was in place at all study hospitals during this time period. Only patients who were admitted without planned limitations of care were considered for study inclusion. Abstractors determined standard pre-hospital predictors of outcome, as well as TH application and eligibility for TH as defined by the standardized clinical protocol. Hospitals were divided into grouped quartiles based on annual volume of patients admitted following OHCA. A test of multiple proportions was applied to assess for differences between hospital quartiles.
A total of 913 patients met study inclusion criteria: 55.2% (504 of 913) patients were eligible for TH at the time of hospital admission, and 46.8% (236 of 504) of these patients received TH. There were no significant differences in the rates of TH provided at hospitals in the top three quartiles (from highest to lowest volume quartiles, rates of TH were 47.1%, 46.3% and 57.0%, overall chi square = 2.71 with alpha = 0.26). However, rates of TH were much lower at hospitals in the lowest volume quartile (less than 3 study cases per year) as compared to all other quartiles (15.4%, overall chi square = 13.6 with alpha = 0.004).
We conclude that, except among hospitals with the very least experience, rates of TH application are similar regardless of annual volume of patients admitted following OHCA.