Dual Defibrillation is Highly Variable: An Analysis of Pulse Interval Delivered in Dual Defibrillation

Area of Science:

• Cardiology
• Emergency Medicine
• Medical Devices

Background:

• Dual defibrillation (DD) is used for refractory ventricular fibrillation (RVF).
• DD can be dual simultaneous (DSiD) or dual sequential (DSD) based on pulse intervals.
• Current manual DD techniques lack standardization, and their impact on pulse intervals is unstudied.

Purpose of the Study:

• To measure timing of four DD methods.
• To determine inter-shock intervals and classify shocks as DSiD or DSD.
• To assess if delivered pulse intervals align with previously reported optimums.

Main Methods:

• Prospective evaluation of four DD techniques (SOSI, TOSI, SOSE1, SOSE2) by physicians, nurses, and paramedics.
• Utilized two defibrillator types in a simulation center.
• Single-blinded study design.

Main Results:

• Pulse intervals varied widely (0–1800 msec) across methods and defibrillators.
• 85.9% of attempts were DSD, 14.1% were DSiD.
• 49.4% of attempts delivered previously reported optimum pulse intervals.

Conclusions:

• Current manual DD methods produce highly variable pulse intervals.
• The efficacy of DD is difficult to ascertain without measuring delivered pulse intervals.
• Reproducible methods for precise pulse intervals are needed for effective DD.