PMID: 7978550May 1, 1994

Noninvasive recovery of acinar anatomic information from CO2 expirograms

Annals of Biomedical Engineering
J D SchwardtP W Scherer


A numerical single path model of respiratory gas exchange with distributed alveolar gas sources was used to estimate the anatomical changes in small peripheral airways such as occur in chronic obstructive pulmonary diseases (COPD). A previous sensitivity analysis of the single path model showed that decreasing total acinar airway cross-sectional area by an area reduction factor, R, results in computed gas expirograms with Phase III steepening similar to that observed in COPD patients. From experimental steady state CO2 washout data recorded from six healthy subjects and six COPD patients, optimized area reduction factors for the single path model were found that characterize peripheral airway anatomy for each subject. Area reduction factors were then combined with measured functional residual capacity data to calculate the normalized peripheral airspace diameters in a given subject, relative to the airspace diameters in the generations of an idealized standard lung. Mean area reduction factors for the patient subgroup were 63% of those for the healthy subgroup, which is related to the gas transport limitation observed in disease. Mean airspace sizes for the patient subgroup were 235% of the healthy subgroup, which characterizes...Continue Reading


Nov 1, 1976·Respiration Physiology·R W MazzoneL E Farhi
Apr 1, 1975·Journal of Applied Physiology·P W SchererA Bouhuys
Jun 1, 1975·Journal of Applied Physiology·J E Hansen, E P Ampaya
Jun 1, 1975·Computers and Biomedical Research, an International Journal·L BakerR A Rhoades
Jan 1, 1992·Diabetic Medicine : a Journal of the British Diabetic Association·R G Petty, J D Pearson
Jun 1, 1992·Respiration Physiology·G R NeufeldP W Scherer
Jan 1, 1991·Annals of Biomedical Engineering·J D SchwardtP W Scherer
Apr 1, 1991·Respiration Physiology·G R NeufeldP W Scherer
Feb 1, 1986·Journal of Pharmacokinetics and Biopharmaceutics·E A Lane, I Parashos
Mar 1, 1988·Journal of Applied Physiology·P W SchererG R Neufeld
Dec 1, 1985·Respiration Physiology·D M Drechsler ParksJames S Ultman
Nov 1, 1972·Journal of Applied Physiology·W HoggP T Macklem
Jan 1, 1973·Journal of Applied Physiology·K Prowse, G Cumming
Nov 1, 1971·Thorax·M C Jones, G O Thomas
Jun 20, 1968·The New England Journal of Medicine·J C HoggW M Thurlbeck
Jul 1, 1983·Preventive Medicine·H L MetznerJ House


Aug 18, 2004·Canadian Journal of Anaesthesia = Journal Canadien D'anesthésie·Gerardo TusmanElsio Turchetto
Jan 1, 1996·Respiration Physiology·P W SchererG R Neufeld
Jul 23, 2003·Respiratory Physiology & Neurobiology·J P WhiteleyC E W Hahn
Jul 1, 1997·American Journal of Respiratory and Critical Care Medicine·K YamaguchiE Koda
Jun 12, 2009·Journal of Clinical Monitoring and Computing·Gerardo TusmanFernando Clara
Oct 26, 2005·Toxicology and Applied Pharmacology·Adekemi TaylorJames S Ultman
Oct 1, 2005·Inhalation Toxicology·Wade H ReeserAbdellaziz Ben-Jebria
May 3, 2014·Current Opinion in Critical Care·Fernando Suarez-SipmannGerardo Tusman
Aug 15, 2019·Jornal brasileiro de pneumologia : publicaça̋o oficial da Sociedade Brasileira de Pneumologia e Tisilogia·Mônica Corso PereiraRosemeri Maurici
Aug 15, 2018·Frontiers in Physiology·Ramin GhorbaniFlorian M Schmidt
Apr 2, 2005·Journal of Applied Physiology·G TusmanS H Böhm

Related Concepts

Carbon Dioxide
In Silico
Computer Assisted Diagnosis
Lung Diseases, Obstructive
Lung Volume Measurements
Pulmonary Gas Exchange

Trending Feeds


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.

Alzheimer's Disease: MS4A

Variants within the membrane-spanning 4-domains subfamily A (MS4A) gene cluster have recently been implicated in Alzheimer's disease in genome-wide association studies. Here is the latest research on Alzheimer's disease and MS4A.

Pediculosis pubis

Pediculosis pubis is a disease caused by a parasitic insect known as Pthirus pubis, which infests human pubic hair, as well as other areas with hair including eye lashes. Here is the latest research.

Rh Isoimmunization

Rh isoimmunization is a potentially preventable condition that occasionally is associated with significant perinatal morbidity or mortality. Discover the latest research on Rh Isoimmunization here.

Genetic Screens in iPSC-derived Brain Cells

Genetic screening is a critical tool that can be employed to define and understand gene function and interaction. This feed focuses on genetic screens conducted using induced pluripotent stem cell (iPSC)-derived brain cells. It also follows CRISPR-Cas9 approaches to generating genetic mutants as a means of understanding the effect of genetics on phenotype.

Enzyme Evolution

This feed focuses on molecular models of enzyme evolution and new approaches (such as adaptive laboratory evolution) to metabolic engineering of microorganisms. Here is the latest research.

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.

Pharmacology of Proteinopathies

This feed focuses on the pharmacology of proteinopathies - diseases in which proteins abnormally aggregate (i.e. Alzheimer’s, Parkinson’s, etc.). Discover the latest research in this field with this feed.

Alignment-free Sequence Analysis Tools

Alignment-free sequence analyses have been applied to problems ranging from whole-genome phylogeny to the classification of protein families, identification of horizontally transferred genes, and detection of recombined sequences. Here is the latest research.