Mechanisms of functional loss in patients with chronic lung disease.


Journal Article (Review)

Functional loss (often quantified as exercise limitation) is common in patients with chronic lung disease. The factors involved are multiple and many may be present together in a given patient. Ventilatory factors involve an imbalance in load/capacity relationships. Specifically, breathing loads from abnormal respiratory-system mechanics and/or excessive ventilatory demand cannot be handled by respiratory muscles that are dysfunctional or malpositioned. Gas-exchange factors involve impaired ventilation-perfusion relationships that lead to hypoxemia, impaired oxygen delivery, and pulmonary hypertension. Cardiovascular factors involve coexisting intrinsic heart disease, right-ventricular overload from pulmonary vascular abnormalities, and simple deconditioning. Skeletal muscle (both respiratory and limb) factors involve direct inflammatory mediator effects on muscle function, malnutrition, blood-gas abnormalities, compromised oxygen delivery from right-heart dysfunction, electrolyte imbalances, drugs, and comorbid states. Other less well understood factors include excessive dyspnea, impaired motivation, orthopedic issues, and psychiatric issues.

Full Text

Duke Authors

Cited Authors

  • MacIntyre, NR

Published Date

  • September 2008

Published In

Volume / Issue

  • 53 / 9

Start / End Page

  • 1177 - 1184

PubMed ID

  • 18718036

Pubmed Central ID

  • 18718036

International Standard Serial Number (ISSN)

  • 0020-1324


  • eng

Conference Location

  • United States