Effects of a single-lung recruitment maneuver on the systemic release of inflammatory mediators.

Abstract

To study the hypothesis, that systemic levels of pro-inflammatory and anti-inflammatory cytokines may be affected by a single recruitment maneuver in mechanically ventilated patients. Prospective, interventional clinical trial. Intensive care unit of a university hospital. Sixteen mechanically ventilated patients with clinical and radiological signs of atelectasis. A single recruitment maneuver (RM) was performed by elevating the airway pressure to 40 cmH(2)O for 7s. Plasmatic concentrations of interleukin (IL)-1beta, IL-6, IL-8, IL-10, IL-12p70 and tumor necrosis factor (TNF-alpha), arterial blood gases and hemodynamic parameters were measured immediately before and 5-360 min after the RM. The RM caused a minor, nevertheless significant improvement of oxygenation (p = 0.02) and carbon dioxide elimination (p=0.006) as well as a moderate drop of the mean arterial pressure (p=0.025). In contrast, plasma concentrations remained unaffected by the RM in all six mediators measured. A single inflation with an airway pressure of 40cmH(2)O for 7 s improved gas exchange only slightly and did not modify systemic levels of inflammatory mediators in mechanically ventilated patients with radiological evidence of atelectasis.