Document Detail


Effect of slowly increasing elastic load on breathing in conscious humans.
MedLine Citation:
PMID:  2032994     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Because the detection of added loads is a function of the step change in load relative to background level of load (Weber's law), we reasoned that detection may be delayed if the load is increased in very small steps over a protracted period. This would permit the study of subliminal load responses over a greater range than would otherwise be possible. In 13 healthy males, an external elastic load (delta E) was added in very small steps (load increased every few seconds) such that delta E increased from zero to 6.0 cmH2O/l in 18 min. Each subject underwent a control study in which an identical protocol was followed but no load was added. Five subjects sensed the load after a variable period of load application. Their results were discarded. In the remaining eight subjects, there was no perception of increased load throughout the 18 min. By comparison with the control studies in the same subjects, there was a progressive reduction in tidal volume and breath duration with loading. To assess the response to an increase in load associated with perception, in five of the eight "nonsensers" the load was suddenly doubled (delta E = 6 cmH2O/l) at the end of the 18 min of progressive nonsensed loading. This evoked perception in all subjects and was associated with highly variable responses in tidal volume and breath duration. We conclude that tachypnea associated with elastic loading in conscious humans is a reflex response that is facilitated by consciousness but does not require perception.
Authors:
A Puddy; M Younes
Related Documents :
19596464 - Breathing mechanics during exercise with added dead space reflect mechanisms of ventila...
11960944 - Determinants of exercise performance in normal men with externally imposed expiratory f...
8376294 - Laryngeal and pump muscle activities during co2 breathing in neonates.
6802664 - Effect of oxygen on breathing during exercise in patients with chronic obstructive lung...
12783774 - Influence of prolonged endurance cycling and recovery diet on intramuscular triglycerid...
24663334 - Cardiopulmonary fitness and heart rate recovery as predictors of mortality in a referra...
Publication Detail:
Type:  Journal Article; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Journal of applied physiology (Bethesda, Md. : 1985)     Volume:  70     ISSN:  8750-7587     ISO Abbreviation:  J. Appl. Physiol.     Publication Date:  1991 Mar 
Date Detail:
Created Date:  1991-06-24     Completed Date:  1991-06-24     Revised Date:  2013-09-26    
Medline Journal Info:
Nlm Unique ID:  8502536     Medline TA:  J Appl Physiol (1985)     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  1277-83     Citation Subset:  IM; S    
Affiliation:
Department of Medicine, University of Manitoba, Winnipeg, Canada.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adult
Airway Resistance / physiology
Biomechanics
Elasticity
Humans
Lung Diseases, Obstructive / physiopathology
Male
Reflex / physiology
Respiratory Mechanics / physiology*
Sensation / physiology
Tidal Volume / physiology
Grant Support
ID/Acronym/Agency:
HL-32030/HL/NHLBI NIH HHS

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Restraining hamsters alters their breathing pattern.
Next Document:  Inspiratory resistive load detection in conscious dogs.