| 释义 | DictionarySeezone lung zone
 lung zoneA hypothetical region of the lung defined by the relationship between the degree of alveolar ventilation and pulmonary blood flow (perfusion). Three lung zones have been identified: I, ventilation exceeds perfusion; II, ventilation and perfusion are equal; and III, perfusion exceeds ventilation. Zone I is found in the upper lung field, where gravity impedes perfusion, and zone III in the inferior portion of the lung, where gravity assists perfusion. See also: zoneFinancialSeeZone |