Lung injury in brain ischemia/reperfusion is exacerbated by mechanical ventilation with moderate tidal volume in rat.
Am J Physiol Regul Integr Comp Physiol. 2020 May 27;:
Authors: Naseh M, Dehghanian A, Keshtgar S, Ketabchi F
INTRODUCTION: Ischemic stroke is one of the most frequent causes of injury in the central nervous system which may lead to multi-organ dysfunction, including the lung. The aim of this study was to investigate whether brain ischemia/reperfusion with or without mechanical ventilation leads to lung injury.
METHOD: Male Sprague Dawley rats were assigned to 4 groups of Sham, 1-hour brain ischemia (MCAO)/24 hours reperfusion (I/R), mechanical ventilation with moderate tidal volume (MTV), and I/R+MTV. The pulmonary capillary permeability (Kfc) was measured in the isolated perfused lung. Mean arterial blood pressure (MAP), heart rate (HR), blood gas variables, histopathological parameters, lungs’ GPx and TNF-α were measured.
RESULTS: Kfc in the groups of I/R, MTV, and I/R+MTV were higher than that in the Sham group. In the I/R, MTV, and I/R+MTV groups, PaO2 and PaO2/FIO2 were lower, whereas, PaCO2 were higher than those in the Sham group. The histopathological score in the I/R group was more than that in the Sham group, and in the MTV and I/R+MTV groups were higher than those in the Sham and I/R groups. Furthermore, there were stepwise rises of TNF-α in the I/R, MTV and I/R+MTV groups, respectively. There was no significant difference in MAP between groups. However, HR in the MTV group was higher than that in the Sham group.
CONCLUSION: Brain ischemia/reperfusion leads to pulmonary capillary endothelial damage and the impairment of gas exchange in the alveolar-capillary barrier, which is exacerbated by mechanical ventilation with moderate tidal volume partially linked to inflammatory reactions.
PMID: 32459970 [PubMed – as supplied by publisher]