Carbon Monoxide Disposition and Permeability-Surface Area Product in the Foetal Circulation of the Perfused Term Human Placenta

• Published in: Placenta (Eastbourne) 2003-01, Vol.24 (1), p.8-11
• Main Authors: Sangalli, M.R., Mclean, A.J., Peek, M.J., Rivory, L.P., Le Couteur, David G.
• Format: Article
• Language: English
• Subjects: Adult; Biological and medical sciences; Capillary Permeability - physiology; Carbon Monoxide - metabolism; Female; Fetus - blood supply; Fundamental and applied biological sciences. Psychology; Humans; Maternal-Fetal Exchange - physiology; Models, Biological; Mother. Fetoplacental unit. Mammary gland. Milk; Perfusion; Placenta - blood supply; Placenta - metabolism; Pregnancy; Pregnancy. Parturition. Lactation; Surface Properties; Vertebrates: reproduction
• ISSN: 0143-4004; 1532-3102
• DOI: 10.1053/plac.2002.0877

In order to estimate the placental barrier to gas transfer, a novel carbon monoxide (CO) wash-in method was used to estimate the permeability-surface area (PS) product for the transfer of gas across the foetal circulation in the perfused human term placenta. The PS product for CO was 0.0096±0.006ml/s/g or 0.012±0.007ml/s/g using compartmental or Crone–Renkin analysis, respectively. Using this result and a published estimate of the placental capillary surface area, the permeability coefficient to CO across the foetal circulation was found to be approximately 4×10−5cm/s. This result is compatible with the hypothesis that the foetal circulation of the human placenta imposes a potentially significant barrier to gas transfer.