TY - CHAP M1 - Book, Section TI - Ventilation-Perfusion Relationships A1 - Levitzky, Michael G. A2 - Levitzky, Michael A2 - McDonough, Kathleen A2 - Kaye, Alan David A2 - Hall, Stanley Y1 - 2021 N1 - T2 - Clinical Physiology in Anesthetic Practice AB - Alveolar ventilation brings inspired gas with a PO2 of about 150 mm Hg and a PCO2 of about 0.3 mm Hg into the alveoli. At the same time, the right ventricle pumps mixed venous blood with a PO2 of about 40 mm Hg and a PCO2 of about 45 mm Hg into the pulmonary capillaries. Oxygen diffuses from the alveoli into the pulmonary capillaries at the same time that carbon dioxide diffuses from the pulmonary capillaries. The PO2 and PCO2 of an alveolar-capillary unit are determined by the relative ventilation and perfusion of the unit. Increasing the ventilation relative to the perfusion increases the PO2 and decreases the PCO2 of the alveolus. Increasing the perfusion relative to the ventilation decreases the PO2 and increases the PCO2 of that alveolus. SN - PB - McGraw Hill CY - New York, NY Y2 - 2024/04/19 UR - accessanesthesiology.mhmedical.com/content.aspx?aid=1175535066 ER -