Wu Jun-Yuan, Li Chun-Sheng, Liu Zhao-Xia, Wu Cai-Jun, Zhang Gui-Chen
Emergency Department, affiliated Chao Yang Hospital of Capital Medical University, Chao yang district, Beijing 100020, China.
Am J Emerg Med. 2009 Sep;27(7):823-9. doi: 10.1016/j.ajem.2008.07.001.
Chest compressions performed by some medical workers are of poor quality, which are too few and shallow with incomplete release. This study was designed to compare the effects of these clinical quality chest compressions with standard manual chest compressions in a porcine model of cardiac arrest.
Ventricular fibrillation was induced in 18 pigs by programed electrical stimulation. Then, 40 mg methylene blue was injected into right atrium after 4 minutes of untreated ventricular fibrillation (VF), followed by cardiopulmonary resuscitation for 9 minutes. Defibrillation was attempted at 13 minutes of cardiac arrest. Animals of no restoration of spontaneous circulation after 4 times of defibrillations were announced dead and dissected immediately to observe the cerebral perfusion with methylene blue coloration. Resuscitated animals were executed to remove the tissues of pallium, cardiac muscle, kidney, and liver for histopathology after evaluating a porcine Cerebral Performance Category score at 24 hours after cardiac arrest. All animals were randomized to the following 2 groups: (1) standard manual chest compressions group (n = 9)-chest compression rates were kept at 100 +/- 5 cpm and compression depth at 50 +/- 1 mm with complete release by Heartstart MRx Monitor; (2) clinical quality chest compressions group (n = 9)-chest compression rates were kept at 80 +/- 5 cpm and compression depth at 37 +/- 1 mm with incomplete release.
Compared with clinical quality chest compressions, standard manual chest compressions produced greater restoration of spontaneous circulation, neurologically normal 24-hour survival, and histopathologic findings.
High-quality chest compressions improve outcomes of resuscitation, especially postresuscitation brain damage.
一些医护人员进行的胸外按压质量较差，按压次数过少、按压过浅且放松不完全。本研究旨在比较在猪心脏骤停模型中这些临床质量的胸外按压与标准徒手胸外按压的效果。
通过程控电刺激在18头猪身上诱发心室颤动。然后，在心室颤动（VF）未治疗4分钟后，向右心房注射40mg亚甲蓝，随后进行9分钟的心肺复苏。在心脏骤停13分钟时尝试除颤。4次除颤后仍未恢复自主循环的动物宣布死亡并立即解剖，观察亚甲蓝染色的脑灌注情况。复苏的动物在心脏骤停后24小时评估猪脑功能分类评分后处死，取出大脑皮质、心肌、肾脏和肝脏组织进行组织病理学检查。所有动物随机分为以下2组：（1）标准徒手胸外按压组（n = 9）——通过Heartstart MRx监护仪将胸外按压频率保持在100±5次/分钟，按压深度保持在50±1mm，并完全放松；（2）临床质量胸外按压组（n = 9）——胸外按压频率保持在80±5次/分钟，按压深度保持在37±1mm，放松不完全。
与临床质量胸外按压相比，标准徒手胸外按压能使自主循环恢复得更好，24小时神经功能正常存活，且组织病理学结果更佳。
高质量的胸外按压可改善复苏结局，尤其是复苏后脑损伤。
