Effect of median sternotomy on respiratory system compliance in humans: evaluation without sophisticated instrumentation.

To evaluate the effect of median sternotomy on the static compliance of the respiratory system (C(RS)) in humans, we used a new technique for pressure-volume (PV) curve tracing without sophisticated instrumentation. The accuracy and the reproducibility of the new technique were tested in a lung simulator, while its agreement with multiple-occlusion (MO) technique (the technique most often used in the ICU for C(RS) measurement) was evaluated in 12 mechanically ventilated patients. Finally, the NCI technique was used in 13 cardiosurgical patients to measure C(RS) before and after median sternotomy.