Lung mechanics, histology, oxygenation and type-III procollagen (PCIII) mRNA were studied aiming to evaluate the need to readjust ventilatory pattern when going from two- to one-lung ventilation (OLV). Wistar rats were assigned to three groups: the left lung was not ventilated while the right lung received: (1) tidal volume (V T)=5ml/kg and positive end-expiratory pressure (PEEP)=2cm H 2O (V5P2), (2) V T=10ml/kg and PEEP=2cm H 2O (V10P2), and (3) V T=5ml/kg and PEEP=5cm H 2O (V5P5). At 1-h ventilation, V5P2 showed hypoxemia, alveolar collapse and impaired lung function. Higher PEEP minimized these changes and prevented hypoxemia. Although high V T prevented hypoxemia and maintained a higher specific compliance than V5P2, a morphologically inhomogeneous parenchyma and higher PCIII expression resulted. In conclusion, the association of low V T and an adequate PEEP level could be useful to maintain arterial oxygenation without inducing a possible inflammatory/remodeling response.
- Extracellular matrix expression
- One-lung ventilation
- Procollagen type-III
- Protective ventilator strategies
- Shear stress
ASJC Scopus subject areas
- Pulmonary and Respiratory Medicine