Anesthetic solubility coefficients for maternal and fetal blood.

Solubility coefficients for seven inhalation anesthetic agnets were determined in maternal and fetal blood at 37 C. Halothane, isoflurane, diethyl ether, and nitrous oxide were significantly more soluble in maternal than in fetal blood, while methoxyflurane, fluroxene, and cyclopropane were significantly less soluble. Reasons for these differences cannot be accounted for by differences in the type or amount of hemoglobin present.