PMID: 3752714Sep 1, 1986Paper

In vivo human tracheal pressure-area curves using computerized tomographic scans. Correlation with maximal expiratory flow rates

The American Review of Respiratory Disease
R MorenoP D Paré

Abstract

In order to develop a simple technique to measure in vivo pressure-area (P-A) curves of the extrathoracic trachea in humans, we studied 14 normal male subjects. Valsalva and Mueller maneuvers were performed at FRC, and tracheal cross-sectional area (TXSA) was measured using computed tomography. Extrathoracic tracheal transmural pressure (TMP) was obtained as airway opening minus atmospheric pressure (Pat). Tracheal "compliance" (TC) was measured on the "inflation" limb of the P-A curve. Tracheal compliance was not a significant predictor of maximal expiratory flow rates, and TXSA at zero TMP was a significant predictor of peak expiratory flow rate but not of FEV1 or Vmax50. P-A curves showed an unexpected configuration characterized by a plateau or an increase in TXSA with TMP lower than -15 cm H2O. P-A curves obtained in 5 subjects using extrathoracic esophageal pressure as tracheal external pressure instead of atmospheric pressure did not show a plateau or an increase in TXSA with Mueller maneuvers. In these 5 subjects, TC using esophageal pressure rather than Pat did not aid in the prediction of flow. We conclude that extrathoracic tracheal external pressure is not Pat because this pressure is probably affected by transmissi...Continue Reading

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.