Lo Bruce M, Quinn Stephen M, Hostler David, Callaway Clifton W
Department of Emergency Medicine, University of Pittsburgh, Pittsburgh, PA, USA.
Resuscitation. 2007 Dec;75(3):469-75. doi: 10.1016/j.resuscitation.2007.06.003. Epub 2007 Jul 17.
Questions remain about the optimal timing and method for treating ventricular fibrillation (VF) during out-of-hospital cardiac arrest, and a variety of treatment protocols are used. Detailed description of rescue shock outcomes during actual patient care under different protocols would allow rational comparison of treatment strategies. The purpose of this study is to describe rescue shock outcomes in a single system using a specific defibrillation protocol.
Patient care records were examined for all adult (age> or =18 years) out-of-hospital cardiac arrest cases treated by an urban paramedic system during a 52-month interval. The immediate outcomes of monophasic rescue shocks were determined from the record and were classified as asystole, VF, restoration of organized electrical activity (ROEA), or restoration of spontaneous circulation (ROSC).
Among 1496 cases of cardiac arrest, 654 received a median of 3 (IQR 1,5) rescue shocks. Of these cases, 408 (28%) had an initial rhythm of VF whereas VF developed later during resuscitation in the remainder. For an initial series of three escalating rescue shocks, most cases of ROSC (9%) and ROEA (12%) occurred after the first shock. The likelihood that a rescue shock would result in ROSC or ROEA increased with witnessed collapse, and rescue shock number. An initial rhythm of asystole was associated with a decreased likelihood that a rescue shock would result in ROEA.
Witnessed collapse and an initial rhythm other than asystole were associated with an increased likelihood of rescue shock success. There is a small but real incremental gain in ROSC and ROEA from delivering three rescue shocks in rapid succession. The greater incidence of rescue shock success with later rescue shocks suggests that VF responds favorably to ongoing resuscitation.
院外心脏骤停时室颤（VF）治疗的最佳时机和方法仍存在疑问，且使用了多种治疗方案。对不同方案下实际患者护理期间的抢救电击结果进行详细描述，将有助于对治疗策略进行合理比较。本研究的目的是使用特定的除颤方案描述单一系统中的抢救电击结果。
检查了城市护理急救系统在52个月期间治疗的所有成人（年龄≥18岁）院外心脏骤停病例的患者护理记录。从记录中确定单相抢救电击的即时结果，并将其分类为心搏停止、室颤、恢复有组织的电活动（ROEA）或恢复自主循环（ROSC）。
在1496例心脏骤停病例中，654例接受了中位数为3次（四分位间距1,5）的抢救电击。在这些病例中，408例（28%）初始心律为室颤，其余病例在复苏后期出现室颤。对于最初一系列三次递增的抢救电击，大多数ROSC（9%）和ROEA（12%）病例发生在第一次电击后。抢救电击导致ROSC或ROEA的可能性随着目击心脏骤停和抢救电击次数的增加而增加。初始心律为心搏停止与抢救电击导致ROEA的可能性降低相关。
目击心脏骤停和初始心律不是心搏停止与抢救电击成功的可能性增加相关。连续进行三次抢救电击可使ROSC和ROEA有微小但实际的增加。后期抢救电击时抢救电击成功的发生率更高，这表明室颤对持续复苏反应良好。
