The effect of patient positioning on dynamic lung compliance.
BACKGROUND
Side-stream spirometry offers a non-invasive method to monitor continuously respiratory mechanics in intubated patients. We studied the effects of different positions on dynamic lung compliance during anaesthesia.


METHODS
The study consisted of 56 patients, operated in supine, prone, kneeling or lateral park-bench position. Dynamic lung compliance and inspiratory peak pressure were recorded after induction of anaesthesia, 15 min and 1 h after posturing the patient.


RESULTS
The first measured compliances were comparable in all groups. The compliance in the lateral and the prone positions was significantly lower than in the supine position at 15 min (P < 0.01) and 1 h (P < 0.001) after the posture change. The peak inspiratory pressure was significantly lower in the kneeling position than in the other groups (P < 0.01 at the first measurement, P < 0.001 at the later measurements). No correlation was found between body mass index and compliance.


CONCLUSIONS
We found that dynamic lung compliance decreased significantly upon change of posture from supine to lateral or prone position, whereas in the kneeling position no change in compliance was observed. We suggest that the kneeling position might be preferable to the prone position.
Tanskanen
P
P
Department of Anaesthesia, Helsinki University Central Hospital, Finland.
Kyttä
J
J
Randell
T
T
D000328:Adult; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008161:Lumbosacral Region / Q000601:surgery; D008170:Lung Compliance / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D011187:Posture / Q000502:physiology*; D016684:Prone Position / Q000502:physiology; D015656:Respiratory Mechanics / Q000502:physiology