Comparison between biphasic quasisinusoidal and truncated waveforms in a swine model of VF

Abstract

Purpose of the study: To compare the effectiveness of biphasic quasisinusoidal (BQ – Gurvich – Venin) waveform (5 ± 1/6 ± 2 ms) and biphasic truncated exponential (BTE) waveform (4.5 ± 0.45/4.5 ± 0.45 ms) in the termination of VF. Materials and methods: This is a controlled experimental study on piglets (n = 14) weighing 25.2 ± 0.73 kg. After induced anesthesia, animals were placed in a supin position, and the trachea was intubated. After intubation, piglets were ventilated with volume – controlled ventilator. VF was induced by drug administration (adrenalin 4 mg and potassium 7.5% – 5 ml intravenously). Induced VF was shocked at 40 s after onset. Two groups were compared (1. BQ waveform by defibrillator DKI – N – 02; 2. BTE waveform by defibrillator DKI – N – 15Ct Biphasic, Metekol, Ukraine). Results: Impedans was no difference between the two groups (59.25 ± 3.7 Ohms vs 58.5 ± 4.5 Ohms). BTE waveform were more safety than BQ – injury threshold 16.7 ± 0.8 amps vs 12.24 ± 1.2 amps and energy injury threshold 50.9 J ± 1.5 vs 23.2 ± 1.6 J. ROSC was achieved in 100% in both groups. Defibrillation threshold was below in BTE waveform group (12.75 ± 1.4 amps vs 21.87 ± 0.8 amps), as and energy defibrillation threshold (22.5 ± 1.7 J vs 57.5 ± 1.3 J). Gurvich electrotherapeutical index1 (correlation between thresholds injury and defibrillation) for BTE waveform 1.30 ± 0.36 vs 0.56 ± 0.29 for BQ waveform. Conclusion: In a swine model VF BTE waveform were more effective and safety than BQ waveform.