On most pulmonary function testing machines, after the patient inspires to total lung capacity
with the test gas, a manual or automatic valve can be selected to close so that the patient's held breath rests tightly against a valve or obstruction.
Pulmonary function tests were as follows: FVC, 1970 mL (72%); FEVI, 930 mL (40%); FEV1/FVC, 47%; residual volume (RV), 2780 (165%); the ratio of residual volume to total lung capacity
1 mL/mmHg/min (81%); and diffusion capacity for CO corrected for total lung capacity
by single breath, 4.
Hypoxemia, hypercarbia, low total lung capacity
, and DLCO were all related to obesity, hypoventilation, and sleep disorders, she noted.
Total lung capacity
drops about 10 percent by age 70, and residual volume increases approximately 20 percent by age 60.
Their FVC was 68%, total lung capacity
was 70%, and diffusing capacity was 47%.