کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
3011163 | 1181553 | 2007 | 11 صفحه PDF | دانلود رایگان |

SummaryIntroductionAlthough the concept of intermittent airway occlusion with the inspiratory impedance threshold valve (ITV) is a well-recognised strategy for improving efficiency of cardiopulmonary resuscitation (CPR), little is known about possible pulmonary side effects.MethodsAfter a baseline chest CT-scan, 24 pigs with beating hearts undergoing apnoeic oxygenation received an injection of a contrast medium and were then assigned randomly to either active compression–decompression CPR with ITV (ACD ITV CPR), ACD CPR alone, or standard-CPR with ITV (standard-ITV CPR), or standard-CPR alone. After a maximum of 5 min of chest compressions or if oxygen saturation dropped below 70%, the experiment was stopped, haemodynamic variables and blood gas values were measured, and another CT-scan was performed; all animals underwent a 30 min recovery-period and a third subsequent CT-scan.ResultsAt baseline arterial oxygen saturation by pulse oxymetry was 99% in all four groups; in both the ACD ITV CPR and the standard-ITV CPR groups, arterial oxygen saturation dropped below 70% within 126 ± 9 s, whereas chest compressions in all ACD CPR and standard-CPR pigs were performed over 5 min (P < 0.001). Before stopping chest compressions arterial oxygen pressure decreased in the ACD ITV CPR group from 426 ± 96 to 42 ± 8 mmHg while it decreased in the ACD CPR group only from 415 ± 116 to 197 ± 127 mmHg (P < 0.001 between groups); in the standard-ITV CPR group arterial oxygen partial pressure decreased from 427 ± 109 to 34 ± 5 mmHg while oxygen partial pressure decreased only from 467 ± 44 to 144 ± 98 mmHg in the standard-CPR group (P < 0.004 between groups). After the second CT scan arterial oxygen partial pressure decreased further to 19 ± 2 mmHg in the ACD ITV CPR versus 210 ± 41 mmHg in the ACD CPR group; to 20 ± 2 mmHg in the standard-ITV CPR versus 148 ± 33 mmHg in the standard-CPR group. Lung-density values (Hounsfield units) were significantly higher in the ACD ITV CPR versus ACD CPR group (−134 ± 54 versus −330 ± 77) and standard-ITV CPR versus standard-CPR group (−98 ± 50 versus −387 ± 42). After a 30 min recovery-period, there were no significant differences in arterial oxygen partial pressure (ACD ITV CPR 275 ± 110 mmHg versus ACD CPR 379 ± 111 mmHg and standard-ITV CPR 265 ± 138 mmHg versus standard CPR 367 ± 55 mmHg). Furthermore, there were no differences in lung density values between groups after 30 min of recovery.ConclusionIn this animal model with a beating heart, intermittent airway obstruction through an ITV combined with apnoeic oxygenation and without active ventilation resulted in hypoxaemia due to transiently impaired lung function.
Journal: Resuscitation - Volume 72, Issue 3, March 2007, Pages 466–476