| Autor: |
Chatziefthimiou A, Makris D, Gourgoulianis K, Triantaris A, Aidonidis I, Zakynthinos G |
| Rok vydání: |
2020 |
| Předmět: |
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| DOI: |
10.21203/rs.3.rs-34407/v1 |
| Popis: |
BackgroundThe effect of elevated PCO2 in the pulmonary vasculature during mechanical ventilation is not clear. Previous studies in ARDS patients have shown that elevated PaCO2 may be associated with pulmonary hypertension however in models of spontaneously breathing animals results were contradictory.Results In this respect, we aimed to investigate the effect of increased PaCO2 on the pulmonary vasculature of rabbits using different levels of tidal volumes during mechanical ventilation. We conducted an experiment using two groups of adult male rabbits (n=30). Animals were randomly allocated in two groups of different tidal volumes either 6 ml/Kgr (LowVt group) or 9 ml/Kgr (HighVt group) and were ventilated with FiO2 0.3 (Normocapnia-1). Subsequently, animals in each Vt group inhaled an enriched in CO2 gas mixture (FiCO2 0.10.) in order to develop hypercapnia (Hypercapnia-1) and were then re-ventilated with the same conditions to develop subsequent phases of normocapnia and hypercapnia (Normocapnia-2,Hypercapnia-2). Pulmonary arterial pressures were measured with a catheter introduced in the pulmonary artery connected to piezo pressure transducers integrated in a polygraphic system.During hypercapnic conditions , both groups showed increase in PAPsyst, PAPdiast and PAPmean compared to their baseline values. PAPmean pressures increased significantly from Normocapnia-2 to Hypercapnia-2 whereas PAPmean at Hypercapnia-2 was found significantly increased compared to Hypercapnia-1.Conclusions These findings suggests that hypercapnia may augment the pressures in pulmonary vasculature during mechanical ventilation an effect that was observed either, using low or, higher tidal volumes. An effect of preconditioning of arterial pulmonary vessels in hypercapnia merits further investigation. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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