Bain A C, Swerdlow C D, Love C J, Ellenbogen K A, Deering T F, Brewer J E, Augostini R S, Tchou P J
Survivalink Corporation, Minneapolis, MN, USA.
Ann Emerg Med. 2001 Jan;37(1):5-12. doi: 10.1067/mem.2001.111690.
The efficacy of a shock waveform for external defibrillation depends on the waveform characteristics. Recently, design principles based on cardiac electrophysiology have been developed to determine optimal waveform characteristics. The objective of this clinical trial was to evaluate the efficacy of principles-based monophasic and biphasic waveforms for external defibrillation.
A prospective, randomized, blinded, multicenter study of 118 patients undergoing electrophysiologic testing or receiving an implantable defibrillator was conducted. Ventricular fibrillation was induced, and defibrillation was attempted in each patient with a biphasic and a monophasic waveform. Patients were randomly placed into 2 groups: group 1 received shocks of escalating energy, and group 2 received only high-energy shocks.
The biphasic waveform achieved a first-shock success rate of 100% in group 1 (95% confidence interval [CI] 95.1% to 100%) and group 2 (95% CI 94.6% to 100%), with average delivered energies of 201+/-17 J and 295+/-28 J, respectively. The monophasic waveform demonstrated a 96.7% (95% CI 89.1% to 100%) first-shock success rate and average delivered energy of 215+/-12 J for group 1 and a 98.2% (95% CI 91.7% to 100%) first-shock success rate and average delivered energy of 352+/-13 J for group 2.
Using principles of electrophysiology, it is possible to design both biphasic and monophasic waveforms for external defibrillation that achieve a high first-shock efficacy.
用于体外除颤的电击波形的疗效取决于波形特征。最近,基于心脏电生理学的设计原则已被开发出来以确定最佳波形特征。本临床试验的目的是评估基于原则的单相和双相波形用于体外除颤的疗效。
对118例接受电生理检查或植入式除颤器的患者进行了一项前瞻性、随机、盲法、多中心研究。诱发室颤,并尝试用双相和单相波形对每位患者进行除颤。患者被随机分为两组:第1组接受能量递增的电击,第2组仅接受高能量电击。
双相波形在第1组(95%置信区间[CI]95.1%至100%)和第2组(95%CI94.6%至100%)中首次电击成功率达到100%,平均释放能量分别为201±17J和295±28J。单相波形在第1组中的首次电击成功率为96.7%(95%CI89.1%至100%),平均释放能量为215±12J;在第2组中的首次电击成功率为98.2%(95%CI91.7%至100%),平均释放能量为352±13J。
利用电生理学原理,可以设计出用于体外除颤的双相和单相波形,使其首次电击疗效较高。