Chang Yun-Te, Tang Wanchun, Wang Jinglan, Brewer James E, Freeman Gary, Sun Shijie, Weil Max Harry
Weil Institute of Critical Care Medicine, Rancho Mirage, CA, USA.
Crit Care Med. 2006 Dec;34(12):3024-8. doi: 10.1097/01.CCM.0000248881.15376.B4.
The effects of two clinically available biphasic waveforms on the success of defibrillation and postresuscitation myocardial dysfunction after prolonged ventricular fibrillation were compared with two newly designed dual-path sequential and simultaneous rectilinear biphasic waveforms. Defibrillation via sequential pulses and encircling, overlapping multiple pathway may depolarize a larger myocardial mass and facilitate transthoracic defibrillation.
Animal study.
Experimental laboratory.
Thirty-two 40 +/- 3 kg pigs.
Ventricular fibrillation was ischemically induced in 32 pigs. After 7 mins of untreated ventricular fibrillation, cardiopulmonary resuscitation was initiated and continued for 5 mins. Animals were then randomized to receive up to three shocks with a) single-path rectilinear biphasic waveform; b) single-path biphasic truncated exponential waveform; c) dual-path rectilinear biphasic sequential defibrillation; or d) dual-path rectilinear biphasic simultaneous defibrillation.
Rectilinear biphasic, dual-path sequential defibrillation, and simultaneous defibrillation had significantly fewer shocks (1.1 +/- 0.4, 1.4 +/- 0.5, 1.3 +/- 0.7, respectively) before restoration of spontaneous circulation than biphasic truncated exponential waveform (2.6 +/- 1.4, p < .005) and less postresuscitation myocardial dysfunction (p < .05). Also, dual-path sequential defibrillation had higher postresuscitation ejection fraction than rectilinear biphasic and dual-path simultaneous defibrillation (p < .005).
The energy requirements for terminating ischemically induced ventricular fibrillation were significantly lower and minimized early postresuscitation myocardial dysfunction in the rectilinear biphasic, dual-path sequential defibrillation, and simultaneous defibrillation than the biphasic truncated exponential waveform. Dual-path sequential defibrillation had less postresuscitation myocardial dysfunction than rectilinear biphasic and dual-path simultaneous defibrillation, but at 72 hrs these differences were no longer significant.
将两种临床可用的双相波与两种新设计的双路径顺序和同步直线双相波进行比较，观察其对长时间室颤后除颤成功率和复苏后心肌功能障碍的影响。通过顺序脉冲和环绕、重叠多路径进行除颤可能会使更大面积的心肌去极化，并有助于经胸除颤。
动物研究。
实验实验室。
32头体重40±3千克的猪。
对32头猪进行缺血性诱导室颤。未经治疗的室颤持续7分钟后，开始进行心肺复苏并持续5分钟。然后将动物随机分组，分别接受以下最多三次电击：a）单路径直线双相波；b）单路径双相截尾指数波；c）双路径直线双相顺序除颤；或d）双路径直线双相同步除颤。
与双相截尾指数波相比，直线双相波、双路径顺序除颤和同步除颤在恢复自主循环前所需的电击次数显著减少（分别为1.1±0.4、1.4±0.5、1.3±0.7），复苏后心肌功能障碍也更少（p<0.05）。此外，双路径顺序除颤的复苏后射血分数高于直线双相波和双路径同步除颤（p<0.005）。
与双相截尾指数波相比，直线双相波、双路径顺序除颤和同步除颤终止缺血性诱导室颤所需的能量显著更低，且能最大程度减少复苏后早期心肌功能障碍。双路径顺序除颤的复苏后心肌功能障碍比直线双相波和双路径同步除颤更少，但在72小时时这些差异不再显著。
