title: Precordial compression without airway management induces lung injury in the rodent cardiac arrest model with central apnea.
abstract: To investigate whether the lung injury induced by precordial compression without ventilation or not, in the cardiac-arrest animal model with central apnea. Thirty male Sprague-Dawley rats were anesthetized with halothane. The cardiac arrest was induced by 100 mg/kg ketamine (IV) and accompanied with central apnea. They were allocated to four groups by means of resuscitation. Group A was treated with only precordial compression without the other treatments. In group B with tracheotomy and precordial compression. In group C was performed tracheotomy, oxygenation, and precordial compression. The animals in group D were treated with tracheotomy, oxygen administration, artificial ventilation, and precordial compression. Four minutes after cardiac arrest, the resuscitation was started and continued for 20 min. PaCO(2) in the group without mechanical ventilation increased significantly after the start of the resuscitation. All animals were sacrificed after resuscitation procedure. The wet/dry weight ratio of lung in group A (6.9+/-0.8) was significantly higher than that of the other groups B, C and D (5.9+/-0.6, 5.7+/-0.4 and 5.6+/-0.4, P<0.05 in each). The pathological findings also demonstrated the lung injuries, such as edema, migration, and destruction of structure in group A. The precordial compression alone did not improve CO(2) elimination in the gasping-less cardiac arrest model, as well as maybe inducing more severe lung injury than that with the protective management. This experimental model raises the possibility that chest compressions without airway management might result in lung injury.
authors.affiliation: Department of Emergency Medicine and Anesthesiology, Fukushima Medical University School of Medicine, 1 Hikarigaoka, Fukushima, Fukushima plefecture 960-1247, Japan. kkawamae@fmu.ac.jp
authors.forename: K
authors.initials: K
authors.lastname: Kawamae
authors.forename: M
authors.initials: M
authors.lastname: Murakawa
authors.forename: M
authors.initials: M
authors.lastname: Otsuki
authors.forename: Y
authors.initials: Y
authors.lastname: Matsumoto
authors.forename: C
authors.initials: C
authors.lastname: Tase
mesh_terms: D000818:Animals; D002245:Carbon Dioxide / Q000097:blood; D016887:Cardiopulmonary Resuscitation / Q000009:adverse effects* / Q000379:methods*; D006324:Heart Arrest, Induced; D008297:Male; D023421:Models, Animal; D010100:Oxygen / Q000097:blood; D011659:Pulmonary Gas Exchange; D051381:Rats; D017207:Rats, Sprague-Dawley; D012128:Respiratory Distress Syndrome / Q000097:blood / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology*; D020182:Sleep Apnea, Central / Q000097:blood / Q000150:complications* / Q000503:physiopathology
chemical_list: D002245:Carbon Dioxide; D010100:Oxygen