Effects of abnormal hemoglobin concentration in human blood on membrane diffusing capacity of the lung and on pulmonary capillary blood volume

Respiration. 1978;36(1):10-8. doi: 10.1159/000193920.


In 13 patients with chronic anemia or polycythemia but normal lung function, and in 7 healthy students a statistically significant correlation between hemoglobin concentration and membrane diffusing capacity of the lung for CO was found. A membrane diffusing constant resulting from extrapolation for hemoglobin concentration 0 g/ was 13.4% of the predicted value (100% for Hb = 14.5 g%). A change of 1 g hemoglobin/100 ml changes membrane diffusing capacity for 6.3% of the predicted value. This result confirms the theory of Koyama and Mochizuki that the diffusing capacity of the pulmonary membrane is a function of the hemoglobin concentration of pulmonary capillary blood. In 3 healthy subjects with normal hemoglobin concentration the effect of DL/VA inhomogenities in the lung on single-breath diffusing capacity and its subdivisions was examined. An increase of DLCO for 20% of predicted normal at decreasing apnea time (tA = 5 sec) resulted from an increased pulmonary capillary blood volume for 50--90% of the predicted value (at tA = 10 sec), whereas membrane diffusing capacity remained unchanged over the range of apnea times. The reasons for this finding are still unknown; alteration of pulmonary perfusion at changing apnea time is taken into account.

MeSH terms

  • Anemia / blood*
  • Apnea
  • Capillaries
  • Carbon Monoxide
  • Hemoglobins*
  • Humans
  • Male
  • Polycythemia / blood*
  • Pulmonary Circulation*
  • Pulmonary Diffusing Capacity*


  • Hemoglobins
  • Carbon Monoxide