Figure 5.
Relationship between the inspiratory change in normalized gas and blood volumes dependent upon fraction of the mass of the entire lung that was atelectatic in expiration (FAMexp). For FAMexp less than 20% minimal relationship was seen; however, within the other two groups there was a clear negative relationship: those regions with the least ventilation received an increase in blood volume and those with the most ventilation a decrease, suggestive of an inspiration-related redistribution that worsened ventilation-perfusion matching.