Therapeutic hypothermia beneficial for postcardiac arrest care

Therapeutic hypothermia (TH) improves neurological outcomes for patients who had sustained cardiac arrests, reports a recent meta-analysis.

Eight randomized controlled trials (RCTs) were retrieved from online databases, corresponding to 2,026 patients who received either TH (n=1,025) or placebo (n=1,001). All studies investigated neurological outcomes as an endpoint. Pooled analysis revealed that TH led to a significantly attenuated risk (risk ratio [RR], 0.87, 95 percent confidence interval [CI], 0.77–0.98; p=0.02).

Mortality, in comparison, was assessed in seven studies, with a cumulative sample size of 1,972 patients. A total of 1,167 deaths were reported. TH had a nonsignificant protective effect against death risk relative to controls (RR, 0.94, 95 percent CI, 0.85–1.03; p=0.17).

However, in the subgroup pf patients with initial shockable rhythm, evaluated in four trials, hypothermia significantly reduced the risk of mortality (RR, 0.85, 95 percent CI, 0.73–0.99). Similarly, its efficacy against poor neurological outcomes remained significant (RR, 0.81, 95 percent CI, 0.67–0.99; p=0.04).

In contrast, TH showed no significant reduction in the risk of mortality (RR, 0.98, 95 percent CI, 0.92–1.04; p=0.50) and poor neurological outcomes (RR, 0.97, 95 percent CI, 0.92–1.01; p=0.15) in patients with initial nonshockable rhythm.

“Our meta-analysis is the largest to date including both shockable and nonshockable cardiac arrest patients. The results confirm improved neurological outcomes noted in other RCTs of TH thus further supporting the current guidelines,” the researchers said, referring to the standards of care that recommend TH for postcardiac arrest patients.