Pulmonary arteriovenous fistulas: increase in shunt at high lung volume.
Intrapulmonary shunt measured in the sitting position by the oxygen breathing method increased at total lung capacity in 7 of 8 patients with pulmonary arteriovenous fistulas. This may explain the clinically noted increased murmur over a fistula on inspiration. The finding of an increased intrapulmonary shunt at total lung capacity might suggest the diagnosis in equivocal cases and provide a convenient test for follow-up after surgery.
D001164:Arteriovenous Fistula / Q000503:physiopathology*; D005652:Functional Residual Capacity; D006801:Humans; D008171:Lung Diseases / Q000503:physiopathology*; D008176:Lung Volume Measurements; D010100:Oxygen; D012119:Respiration; D014109:Total Lung Capacity
D010100:Oxygen