Certain antiarrhythmic drugs improve the chances of patient survival when administered by paramedics to patients with out-of-hospital cardiac arrest who had failed electric shock treatment, a study published in the New England Journal of Medicine has found.

Previous data have shown that only ~10% of patients who suffer an out-of-hospital cardiac arrest survive. Treatments such as CPR and defibrillation can increase a patient’s chance of survival, and now the study’s findings add the possibility of added benefit from some antiarrhythmics.

RELATED: Xenon Shows Promising Improvements in Out-of-Hospital Cardiac Arrests

For the study, Peter Kudenchuk, MD, the principal study author, and colleagues followed the patients from hospital admission to discharge. A total of 3,026 patients with out-of-hospital cardiac arrest caused by ventricular fibrillation and ventricular tachycardia were randomized in the 3-year study. Patients were assigned amiodarone, lidocaine, or placebo by rapid injection along with all the other standard resuscitation treatments.

Continue Reading

Among the 1,900 patients whose cardiac arrest was bystander-witnessed, survival improved significantly from about 23% to 28% by either drug. This finding suggests that “treating patients as soon as possible after their collapse might be a critical determinant of whether drugs like amiodarone or lidocaine will have a significant clinical effect,” Dr. Kudenchuk noted.

The two study drugs, amiodarone and lidocaine, did not statistically significantly improve overall rate of survival to hospital discharge though amiodarone demonstrated a favorable trend in that direction (3%). Survival to discharge was defined as the point at which a patient is discharged from the hospital.

The study was conducted by the Resuscitation Outcomes Consortium.

For more information visit NIH.gov.