Maternal blood-gas tensions (PAO2-PaO2), physiological shunt and Vd/Vt during general anaesthesia for Caesarean

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Instrumentation of Near-term Fetal Sheep for Multivariate Chronic Non-anesthetized Recordings
14:40

Instrumentation of Near-term Fetal Sheep for Multivariate Chronic Non-anesthetized Recordings

Published on: October 25, 2015

G Lyons, M E Tunstall

    British Journal of Anaesthesia
    |November 1, 1979
    PubMed

    Measurements of maternal blood-gas tensions, (PAO2-PaO2), calculated pulmonary venous admixture (physiological shunt) and deadspace/tidal volume ratio (VD/VT) were made in 14 patients undergoing Caesarean section. Measurements were carried out after induction of general anaesthesia, and before delivery, with the patient tilted to the left. With a mean inspired oxygen concentration of 67.5% mean PaO2 was 44.3 kPa, mean (PAO2-PaO2) 18.4 kPa, mean Vd/Vt 32% and mean physiological shunt 9.5%. The findings are compared with published values for non-anesthetized pregnant patients.

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