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

Abstract

Objective: To study the hypothesis, that systemic levels of proinflammatory and anti-inflammatory cytokines may be affected by a single recruitment maneuver in mechanically ventilated patients. Design: Prospective, interventional clinical trial. Setting: Intensive care unit of a university hospital. Patients: Sixteen mechanically ventilated patients with clinical and radiological signs of atelectasis. Interventions: A single recruitment maneuver (RM) was performed by elevating the airway pressure to 40 cmH(2)O for 7 s. Measurements and main results: Plasmatic concentrations of interleukin (IL)-1 beta, 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. Conclusion: A single inflation with an airway pressure of 40 cmH(2)O for 7s improved gas exchange only slightly and did not modify systemic levels of inflammatory mediators in mechanically ventilated patients with radiological evidence of atelectasis.