intrapulmonary shunt [L, intra + pulmoneus, relating to the lung] , (in respiratory therapy) a condition in which a region of the lungs is perfused with little or no ventilation. It is indicated by a low ratio of QS/QT, in which QS represents the difference between end capillary oxygen content and mixed venous oxygen content and QT represents cardiac output. The condition may occur in atelectasis, pneumonia, pulmonary edema, and adult respiratory distress syndrome.
