Factors affecting DLCO

Primary purpose of measuring diffusion capacity is to assess
the barrier for gas transfer at alveolar capillary membrane.
Before we can ascribe a given dicrease in diffusion to AC block
we have to make corrections for variables that can affect
diffusion.
  • Hemoglobin: DLCO CORR
  • Lung volume: DL/VA
  • V/Q mismatch:
  • Pulmonary capillary bed:
  • Alveolar capillary membrane thickness: