Lurie K G, Coffeen P, Shultz J, McKnite S, Detloff B, Mulligan K
Cardiac Arrhythmia Center, University of Minnesota, Minneapolis.
Circulation. 1995 Mar 15;91(6):1629-32. doi: 10.1161/01.cir.91.6.1629.
Active compression-decompression (ACD) cardiopulmonary resuscitation (CPR) has recently been demonstrated to provide significantly more blood flow to vital organs during cardiac arrest. To further enhance the effectiveness of this technique, we tested the hypothesis that intermittent impedance to inspiratory gas exchange during the decompression phase of ACD CPR enhances vital organ blood flow.
ACD CPR was performed with a pneumatically driven automated compression-decompression device in a porcine model of ventricular fibrillation (VF). Nine pigs were randomized to receive ACD CPR alone, while 8 pigs received ACD CPR plus intermittent impedance to inspiratory gas exchange with a threshold valve set to 40 cm H2O. Results comparing 2 minutes of ACD CPR alone versus ACD CPR with the inspiratory impedance threshold valve (ITV) revealed significantly higher mean (+/- SEM) coronary perfusion pressures (diastolic aortic minus diastolic right atrial pressures) in the ITV (31.0 +/- 2.3 mm Hg) group versus with ACD CPR alone (21 +/- 3.6 mm Hg) (P < .05). Total left ventricular and cerebral blood flows, determined by radiolabeled microspheres, were 0.77 +/- 0.095 and 0.47 +/- 0.06 mL/min per gram, respectively, with ACD CPR plus the ITV versus 0.45 +/- 0.1 and 0.32 +/- 0.016 mL/min per gram, respectively, with ACD CPR alone (P < .05). Similar improvements in the ITV group were observed after 7 minutes of ACD CPR. After 16 minutes of VF and 13 minutes of ACD CPR, 6 of 8 pigs in the ITV group were successfully resuscitated with less than three successive 150-J shocks, whereas only 2 of 9 pigs with ACD CPR alone were resuscitated with equivalent energy levels (P < .02). With up to three additional and successive 200-J shocks, all pigs in the ITV group and 7 of 9 pigs with ACD CPR alone were resuscitated (P = .18).
Intermittent impedance to inspiratory flow of respiratory gases during ACD CPR significantly improves coronary perfusion pressures and vital organ blood flow and lowers defibrillation energy requirements in a porcine model of VF.
最近有研究表明，主动压缩-减压（ACD）心肺复苏（CPR）在心脏骤停期间能为重要器官提供显著更多的血流。为进一步提高该技术的有效性，我们检验了以下假设：在ACD CPR的减压阶段对吸气气体交换施加间歇性阻力可增强重要器官的血流。
在猪心室颤动（VF）模型中，使用气动驱动的自动压缩-减压装置进行ACD CPR。9头猪被随机分配仅接受ACD CPR，而8头猪接受ACD CPR加对吸气气体交换的间歇性阻力，阈值阀设定为40 cm H₂O。比较单独进行2分钟ACD CPR与使用吸气阻抗阈值阀（ITV）的ACD CPR的结果显示，ITV组（31.0±2.3 mmHg）的平均（±SEM）冠状动脉灌注压（舒张期主动脉压减去舒张期右心房压）显著高于单独进行ACD CPR组（21±3.6 mmHg）（P<.05）。通过放射性微球测定，使用ACD CPR加ITV时，左心室总血流量和脑血流量分别为0.77±0.095和0.47±0.06 mL/（min·g），而单独进行ACD CPR时分别为0.45±0.1和0.32±0.016 mL/（min·g）（P<.05）。在进行7分钟ACD CPR后，ITV组也观察到了类似的改善。在VF持续16分钟和ACD CPR持续13分钟后，ITV组的8头猪中有6头用少于三次连续150 J的电击成功复苏，而单独进行ACD CPR的9头猪中只有2头用相同能量水平复苏（P<.02）。再施加多达三次连续200 J的电击后，ITV组的所有猪和单独进行ACD CPR的9头猪中有7头被复苏（P=.18）。
在猪VF模型中，ACD CPR期间对呼吸气体吸气流量施加间歇性阻力可显著改善冠状动脉灌注压和重要器官血流，并降低除颤能量需求。
