Hypothermia Treatment Helps Cardiac Arrest Victims

A new study reveals that therapeutic hypothermia (TH) improves survival and neurological outcomes after cardiac arrest in patients with initially non-shockable rhythms.

Researchers at Thomas Jefferson University (Philadelphia, PA, USA), the University of Colorado School of Medicine (Aurora, USA; medschool.ucdenver.edu), and other institutions conducted a retrospective cohort study involving 519 post cardiac-arrest patients with initial non-shockable rhythms to determine whether TH improved their neurologic outcome and survival. Patient and arrest characteristics were used to estimate the propensity to receive TH, including age, sex, location and duration of arrest, and if the arrest was witnessed. To determine the association between TH and outcomes, 201 propensity score matched pairs were compared.

The results showed that TH patients were significantly younger, had longer durations of arrest, and had a higher incidence of asystole as their primary rhythm. Survival to hospital discharge was higher after TH (29%) than after not receiving TH (15%), and cerebral performance was significantly higher for patients who underwent TH (21%) than for patients who did not undergo TH (10%). In all, TH was associated with a 3.5-fold increased likelihood of favorable neurological outcome and 2.8-fold increased likelihood of survival to hospital discharge. The study was published on November 16, 2015, in Circulation.

“Our findings provide further support for the use of TH in patients with initial nonshockable rhythms, given the lack of randomized controlled trial data, and should encourage its use in this patient population while awaiting data from randomized trials,” concluded lead author Sarah Perman, MD, of Thomas Jefferson University, and colleagues. “Regardless of the location of the cardiac arrest, patients who underwent TH were significantly more likely than those who did not receive TH to survive to hospital discharge neurologically intact.”

Therapeutic cooling is among the most potent interventions for hypoxic-ischemic injury, a broad constellation of conditions ranging from cardiac and respiratory arrest to carbon monoxide (CO) and other poisonous gas exposure, and appears to limit tissue damage by reducing oxygen metabolism and inflammation, while maintaining cell membrane integrity. Other studies have shown that HT after cardiac arrest increases patients’ chances of survival by 31% and quality of survival by 41%.

Related Links:
Thomas Jefferson University
University of Colorado School of Medicine