Effect of patient position on intra-thoracic pressure during general anesthesia

AIMS. Change in position during general anesthesia may accompany hemodynamic and mechanical complications. In this study effect of change in position on intra-thoracic pressure during general anesthesia has been studied. METHODS. In this cross-sectional descriptive study, 115 adult patients were evaluated. Peak and plateau intra-thoracic pressures were measured with spirometer in supine position and then peak and plateau intra-thoracic pressure during one to 60 minutes of anesthesia were measured and registered in Trendelenburg, left hemi lateral, right hemi lateral or prone positions in 10 minute intervals. RESULTS. The highest peak and plateau intra-thoracic pressures were registered in supine position and before changing position (33.7±5.5 and 20.5±5.1) that had not significant change during general anesthesia (p > 0.05). Highest intra-thoracic pressure after changing position was registered in right hemi lateral group, and least change of pressure was seen in group who were changed to prone position. CONCLUSION. Change in position of patients during general anesthesia and complete muscle relaxation from supine position to prone, right hemi lateral, left hemi lateral or Trendelenburg positions don’t cause significant clinical change in intra-thoracic pressure.