A Low Tilt Waveform in the Transthoracic Defibrillation of Ventricular Arrhythmias during Cardiac Arrest
Resuscitation, 05/11/2012
Darragh KM et al. – The low tilt waveform used in this study demonstrated first shock success rates in keeping with a commercially available high tilt defibrillator which could result in less myocardial damage due to reduced energy requirements.
Methods- Patients in cardiac arrest who experienced ventricular arrhythmias received shocks from a novel low tilt waveform defibrillator at 120J or a standard tilt waveform defibrillator at 150J.
- Resuscitation guidelines were followed as per Resuscitation Council UK, 2005.
- A shock was successful when the ventricular arrhythmia was terminated for ≥5seconds following shock delivery.
- A total of 113 cardiac arrest cases were included.
- The low tilt device was used for 56 cases and the standard tilt device for 57 cases.
- The presenting rhythm was ventricular fibrillation (VF) in 71.7% (81/113), pulseless electrical activity (PEA) in 15.9% (18/113), ventricular tachycardia (VT) in 9.7% (11/113), asystole in 1.8% (2/113) and narrow complex rhythm in 0.9% (1/113).
- The low tilt device resulted in first shock success in 86% (48/56 cases) versus the standard tilt device first shock success of 77% (44/57 cases).
- There was no significant difference in first shock success between the two devices (p=0.36).



