Intraoperative ventilation strategy during cardiopulmonary bypass attenuates the release of matrix metalloproteinases and improves oxygenation.

Background: Patients undergoing open heart surgery with cardiopulmonary bypass (CPB) often develop a systemic immune reaction, characterized by an increase of proinflammatory and anti-inflammatory mediators. We previously demonstrated that continued mechanical ventilation during CPB reduces this response. We hypothesized that this strategy may also impact on matrix metalloproteinase (MMP) release.

Bbeta(15-42) protects against acid-induced acute lung injury and secondary pseudomonas pneumonia in vivo.

Rationale: Acute lung injury (ALI) is a serious condition in critically ill patients that predisposes to secondary bacterial pneumonia. Vascular leak is a hallmark in the pathogenesis of ALI. The fibrin-derived peptide Bbeta(15-42) was shown to preserve endothelial barriers, thereby reducing vascular leak.