European journal of anaesthesiology
-
To investigate the clinical application of a mathematical model of pulmonary gas exchange, which ascribes hypoxaemia to shunt and ventilation/perfusion mismatch. Ventilation/perfusion mismatch is quantified by deltaPO2, which is the drop in oxygen pressure from alveoli to lung capillaries. Shunt and deltaPO2 were used to describe changes in oxygenation after coronary artery bypass grafting. ⋯ Ventilation/perfusion mismatch (deltaPO2), rather than shunt, explains the changes in postoperative oxygenation. The model of pulmonary gas exchange may serve as a useful and potentially non-invasive clinical tool for monitoring patients at risk of postoperative hypoxaemia.
-
Comparative Study
Postoperative changes in the full-field electroretinogram following sevoflurane anaesthesia.
We tested the hypothesis that disturbances of the visual pathway persist following general anaesthesia, even after normal clinical discharge criteria have been met. ⋯ Postoperative electroretinogram abnormalities are consistently present in patients who have undergone N2O/sevoflurane anaesthesia. These abnormalities persist beyond the time at which standard clinical discharge criteria have been met.
-
The kneeling prone position is often used for low back surgery in order to decrease intraoperative bleeding and increase the surgical exposure of the vertebral canal. The aim of this study was to assess effects of the kneeling prone position on respiratory gas exchange focusing on oxygen consumption and early changes in oxygenation. ⋯ The present study demonstrates that the kneeling prone position improves oxygenation and that the mechanisms involved are fast in onset. Furthermore, the prone position does not change oxygen consumption although alveolar ventilation is significantly reduced. The changes in alveolar ventilation could possibly be the result of circulatory changes caused by the prone position, but further studies are needed to clarify that hypothesis.