Mader Timothy J, Kellogg Adam R, Smith Jeremy, Hynds-Decoteau Rachael, Gaudet Claudia, Caron John, Murphy Brett, Paquette Allie, Sherman Lawrence D
The Department of Emergency Medicine, Baystate Medical Center/Tufts University School of Medicine, Springfield, MA, United States.
Resuscitation. 2008 Jun;77(3):387-94. doi: 10.1016/j.resuscitation.2008.01.007. Epub 2008 Mar 4.
An impedance threshold device (ITD) has been designed to enhance circulation during CPR. A recent study suggests that the ITD does not improve hemodynamics and that it may actually worsen outcomes. We sought to independently assess the effect of the ITD on coronary perfusion pressure (CPP) and passive ventilation (PaCO(2) and PaO(2)) during standard CPR (S-CPR), and its impact on the return of spontaneous circulation (ROSC) and short-term survival in a blinded fashion.
Thirty male swine were instrumented under anesthesia. Ventricular fibrillation (VF) was electrically induced. CPP was continuously recorded. After 8 min of untreated VF, baseline characteristics were documented and S-CPR initiated. After 3 cycles of S-CPR, an ABG was drawn and drugs were given. Following 6 additional cycles of S-CPR, an ABG was drawn and the first rescue shock was delivered. Group comparisons were assessed using descriptive statistics. Proportions with 95% confidence intervals were calculated for outcomes.
Baseline characteristics between the two groups were the same. The mean CPP in the ITD group was 51.2 mmHg [95% CI: 37.7, 64.7] compared to 50.2 mmHg [95% CI: 37.0, 63.4] in the sham group. The PaCO(2) and PaO(2) were 68 Torr [95% CI: 55.7, 79.5] and 103 Torr [95% CI: 76, 129] in the ITD group and 59 Torr [95% CI: 49.1, 68.5] and 137 Torr [95% CI: 83, 191] in the sham group. The rate of ROSC was 14/15 in both groups and 13 animals in each groups survived.
In this independent blinded study, use of the active ITD had no significant impact on CPP, passive ventilation, or outcomes compared to the sham device.
阻抗阈值装置（ITD）旨在在心肺复苏（CPR）期间增强循环。最近的一项研究表明，ITD并不能改善血流动力学，实际上可能会使结果恶化。我们试图以盲法独立评估ITD对标准心肺复苏（S-CPR）期间冠状动脉灌注压（CPP）和被动通气（PaCO₂和PaO₂）的影响，及其对自主循环恢复（ROSC）和短期生存的影响。
30只雄性猪在麻醉下进行仪器植入。通过电诱导心室颤动（VF）。持续记录CPP。未经治疗的VF持续8分钟后，记录基线特征并开始S-CPR。在3个周期的S-CPR后，抽取动脉血气（ABG）并给予药物。在另外6个周期的S-CPR后，抽取ABG并给予首次抢救电击。使用描述性统计进行组间比较。计算结果的95%置信区间的比例。
两组之间的基线特征相同。ITD组的平均CPP为51.2 mmHg [95% CI：37.7, 64.7]，而假手术组为50.2 mmHg [95% CI：37.0, 63.4]。ITD组的PaCO₂和PaO₂分别为68 Torr [95% CI：55.7, 79.5]和103 Torr [95% CI：76, 129]，假手术组分别为59 Torr [95% CI：49.1, 68.5]和137 Torr [95% CI：83, 191]。两组的ROSC率均为14/15，每组有13只动物存活。
在这项独立的盲法研究中，与假装置相比，使用活性ITD对CPP、被动通气或结果没有显著影响。
