Prediction of defibrillation success from a single defibrillation threshold measurement with sequential pulses and two current pathways in humans

• Published in: Circulation (New York, N.Y.) N.Y.), 1988-11, Vol.78 (5), p.1144-1149
• Main Authors: JONES, D. L, KLEIN, G. J, GUIRAUDON, G. M, SHARMA, A. D, YEE, R, KALLOK, M. J
• Format: Article
• Language: English
• Subjects: Adult; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Arrhythmias, Cardiac - surgery; Biological and medical sciences; Electric Countershock - methods; Emergency and intensive cardiocirculatory care. Cardiogenic shock. Coronary intensive care; Evaluation Studies as Topic; Female; Humans; Intensive care medicine; Intraoperative Period; Male; Medical sciences; Middle Aged; Prognosis; Random Allocation; Ventricular Fibrillation - therapy
• ISSN: 0009-7322; 1524-4539
• DOI: 10.1161/01.CIR.78.5.1144

The ultimate aim of defibrillation testing is to predict consistent defibrillation. This study tested the hypothesis that defibrillation success could be predicted from a single measurement of defibrillation threshold. We measured defibrillation threshold by using three patch electrodes and a standard protocol intraoperatively in 49 patients undergoing arrhythmia surgery. Each patient was then assigned to one of five energy subgroups (0.5, 1.0, 1.5, 2.0, or 2.5 times defibrillation threshold) for a single shock (followed by a rescue shock if necessary) for a subsequent ventricular fibrillation episode. A curve relating percent success to energy was then constructed for the group. Defibrillation threshold averaged 4.7 +/- 2.98 J for the group (mean +/- SD). There was a curvilinear relation between the energy of the defibrillation threshold ratio test shock and percent success: 33.3%, 58.3%, 81.8%, 91.7%, and 100% at mean defibrillation threshold ratios of 0.56 +/- 0.14, 1.02 +/- 0.07, 1.53 +/- 0.14, 1.88 +/- 0.09, and 2.60 +/- 0.14, respectively. We conclude that consistent defibrillation is predictable from a single measurement of defibrillation threshold. Furthermore, for an individual patient, a safety margin of 2.6 times defibrillation threshold should approximate 100% successful defibrillation for a single test shock.