Amiodarone, Lidocaine, or Placebo in Out-of-Hospital Cardiac Arrest

Multiple studies questioned use of adrenaline during out of hospital cardiac arrest, showing increased likelihood ROSC, at the expense of worse neurological outcomes (see here and here). 

This week sees the publication of another study, questioning utility (or possibly futility) of Amiodarone or Lignocaine for out-of-hospital cardiac arrest for shock-refractory ventricular fibrillation or pulseless ventricular tachycardia (open access here)

In this randomised, double-blind trial, researchers compared parenteral amiodarone, lidocaine, and saline placebo, along with standard care, in adults who had non-traumatic out-of-hospital cardiac arrest, shock-refractory ventricular fibrillation or pulseless ventricular tachycardia after at least one shock, and vascular access. Paramedics enrolled patients at 10 North American sites.

The primary outcome was survival to hospital discharge; the secondary outcome was favourable neurologic function at discharge.

3026 patients were randomly assigned to amiodarone (974), lidocaine (993), or placebo (1059). 24.4%, 23.7%, and 21.0%, respectively, survived to hospital discharge. Neurologic outcome at discharge was similar in the three groups.

There was some indication that giving drugs early was associated with improved outcomes (not statistically significant).

The authors conclude that overall, neither amiodarone nor lidocaine resulted in a significantly higher rate of survival or favourable neurologic outcome than the rate with placebo among patients with out-of-hospital cardiac arrest due to initial shock-refractory ventricular fibrillation or pulseless ventricular tachycardia.

However they did add the following comment - "Nonetheless, the suggestion that survival was improved by drug treatment in patients with witnessed out-of-hospital cardiac arrest, without evidence of harm in those with unwitnessed arrest, merits thoughtful consideration."

Food for thought for your next CPR case…

 

Further Reading

Kudenchuk PJ, Brown SP, Daya M, Rea T, Nichol G, Morrison LJ, Leroux B, Vaillancourt C, Wittwer L, Callaway CW, Christenson J, Egan D, Ornato JP, Weisfeldt ML, Stiell IG, Idris AH, Aufderheide TP, Dunford JV, Colella MR, Vilke GM, Brienza AM, Desvigne-Nickens P, Gray PC, Gray R, Seals N, Straight R, Dorian P; Resuscitation Outcomes Consortium Investigators. Amiodarone, Lidocaine, or Placebo in Out-of-Hospital Cardiac Arrest. N Engl J Med. 2016 Apr 4. [Free Full Text From NEJM]