Dorfsman M L, Menegazzi J J, Wadas R J, Auble T E
University of Pittsburgh Affiliated Residency in Emergency Medicine, Center for Emergency Medicine for Western Pennsylvania, Pittsburgh, PA 15213, USA.
Acad Emerg Med. 2000 Oct;7(10):1077-82. doi: 10.1111/j.1553-2712.2000.tb01255.x.
Previous experiments in the authors' swine lab have shown that cardiopulmonary resuscitation (CPR) using two-thumb chest compression with a thoracic squeeze (TT) produces higher blood and perfusion pressures when compared with the American Heart Association (AHA)-recommended two-finger (TF) technique. Previous studies were of short duration (1-2 minutes). The hypothesis was that TT would be superior to TF during prolonged CPR in an infant model.
This was a prospective, randomized crossover experiment in a laboratory setting. Twenty-one AHA-certified rescuers performed basic CPR for two 10-minute periods, one with TT and the other with TF. Trials were separated by 2-14 days, and the order was randomly assigned. The experimental circuit consisted of a modified manikin with a fixed-volume arterial system attached to a neonatal monitor via an arterial pressure transducer. The arterial circuit was composed of a 50-mL bag of normal saline solution (air removed) attached to the manikin chest plate and connected to the transducer with a 20-gauge intravenous catheter and tubing. Rescuers were blinded to the arterial pressure tracing. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) were recorded in mm Hg, and pulse pressures (PPs) were calculated. Data were analyzed with two-way repeated-measures analysis of variance. Sphericity assumed modeling, with Greenhouse-Geisser and Huynh-Feldt adjustments, was applied.
Marginal means for TT SBP (68.9), DBP (17.6), MAP (35.3), and PP (51.4) were higher than for TF SBP (44.8), DBP (12.5), MAP (23.3), and PP (32.2). All four pressures were significantly different between the two techniques (p< or =0.001).
In this infant CPR model, TT chest compression produced higher MAP, SBP, DBP, and PP when compared with TF chest compression during a clinically relevant duration of prolonged CPR.
作者在猪实验室之前的实验表明，与美国心脏协会（AHA）推荐的两指（TF）技术相比，采用双拇指胸部按压并胸部挤压（TT）进行心肺复苏（CPR）时可产生更高的血压和灌注压。之前的研究持续时间较短（1 - 2分钟）。本研究的假设是，在婴儿模型的长时间CPR过程中，TT技术优于TF技术。
这是一项在实验室环境中进行的前瞻性、随机交叉实验。21名获得AHA认证的救援人员进行两个10分钟时段的基础CPR，一个时段采用TT技术，另一个时段采用TF技术。两次试验间隔2 - 14天，顺序随机分配。实验回路由一个改良的人体模型组成，其具有一个固定容积的动脉系统，通过动脉压力传感器连接到新生儿监护仪。动脉回路由一袋50毫升的生理盐水溶液（已排空气）连接到人体模型胸板，并通过一根20号静脉导管和 tubing连接到传感器。救援人员对动脉压波形图不知情。以毫米汞柱记录收缩压（SBP）、舒张压（DBP）和平均动脉压（MAP），并计算脉压（PP）。数据采用双向重复测量方差分析进行分析。应用了假设球对称性的建模，并进行了Greenhouse - Geisser和Huynh - Feldt校正。
TT技术的SBP（68.9）、DBP（17.6）、MAP（35.3）和PP（51.4）的边际均值高于TF技术的SBP（44.8）、DBP（12.5）、MAP（23.3）和PP（32.2）。两种技术之间的所有四个压力均有显著差异（p≤0.001）。
在这个婴儿CPR模型中，在临床相关的长时间CPR期间，与TF胸部按压相比，TT胸部按压产生了更高的MAP、SBP、DBP和PP。
