Hypotensive anesthesia and its safety limit. Centering on lung gas exchange.

Controlled gas exchange in whole lung bioreactors.

In cellular, tissue-level or whole organ bioreactors, the level of dissolved oxygen is one of the most important factors requiring control. Hypoxic environments may lead to cellular apoptosis, while hyperoxic environments may lead to cellular damage or dedifferentiation, both resulting in loss of overall tissue function. This manuscript describes the creation, characterization and validation of...

How does lung structure affect gas exchange?

The lung is characterized morphologically by establishing a very large surface and an exceedingly thin barrier between air and blood. A model for relating these structural features to the lung's gas exchange function is first developed. It is then shown that DO2 estimated by morphometry is about two times larger than that estimated by physiology; there are possible reasons for this. Comparing a...

Hypotensive epidural anesthesia for total hip

Hypotensive epidural anesthesia provides arterial hypotension to maintain a mean arterial pressure of 50 mmHg and it can be used to reduce blood loss during total hip replacement. The technique combines an extensive epidural blockade with an intravenous infusion of low-dose epinephrine. This results in arterial hypotension, but with preservation of central venous pressure, heart rate, stroke vo...

Gas exchange and its effect on blood gas concentrations in the amphibian, Xenopus laevis.

Gas exchange and ventilation-perfusion relationships in the lung.

This review provides an overview of the relationship between ventilation/perfusion ratios and gas exchange in the lung, emphasising basic concepts and relating them to clinical scenarios. For each gas exchanging unit, the alveolar and effluent blood partial pressures of oxygen and carbon dioxide (PO2 and PCO2) are determined by the ratio of alveolar ventilation to blood flow (V'A/Q') for each u...