Document Detail

Ventilatory and cardiovascular responses to hypercapnia after 20 days of head-down bed rest.
MedLine Citation:
PMID:  15086120     Owner:  NLM     Status:  MEDLINE    
INTRODUCTION: Few studies have attempted to investigate the influence of prolonged head-down bed rest (HDBR) on hypercapnic ventilatory chemosensitivity, and there are no data available regarding associated changes in arterial BP and heart rate (HR). The aim of this study was to clarify the influence of prolonged HDBR on ventilatory and cardiovascular responses to hypercapnia. METHODS: There were five healthy men who participated in this study. Resting ventilatory and cardiovascular responses to hypercapnia were measured by means of Read's CO2 rebreathing method 4 d before and on the 19th day of HDBR. Measured variables included systolic and diastolic BP (SBP and DBP, respectively), inspired minute ventilation (VI), and end-tidal partial pressure of CO2 (PETCO2). RESULTS: Ventilatory response to hyperoxic hypercapnia (deltaVI/ deltaPETCO2) decreased significantly on the 19th day of HDBR (1.42 +/- 0.65 to 0.90 +/- 0.41 L x min(-1) x torr(-1), p < 0.05). On the other hand, SBP, DBP, and HR responses (deltaSBP/deltaPETCO2, deltaDBP/deltaPETCO2, and deltaHR/deltaPETCO2) were unchanged. DISCUSSION: The results from this study suggest that prolonged HDBR leads to diminished central hypercapnic ventilatory chemosensitivity.
Keisho Katayama; Kohei Sato; Hiroshi Akima; Koji Ishida; Toshio Yanagiya; Hiroaki Kanehisa; Hideoki Fukuoka; Tetsuo Fukunaga; Miharu Miyamura
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Aviation, space, and environmental medicine     Volume:  75     ISSN:  0095-6562     ISO Abbreviation:  Aviat Space Environ Med     Publication Date:  2004 Apr 
Date Detail:
Created Date:  2004-04-16     Completed Date:  2004-08-02     Revised Date:  2004-11-17    
Medline Journal Info:
Nlm Unique ID:  7501714     Medline TA:  Aviat Space Environ Med     Country:  United States    
Other Details:
Languages:  eng     Pagination:  312-6     Citation Subset:  IM; S    
Research Center of Health, Physical Fitness and Sports, Nagoya University, Nagoya, Japan.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Bed Rest*
Cardiovascular System / physiopathology*
Hypercapnia / complications*,  physiopathology
Prone Position / physiology*
Respiratory System / physiopathology*

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

Previous Document:  Display color affects motion sickness symptoms in an optokinetic drum.
Next Document:  Back muscle EMG of helicopter pilots in flight: effects of fatigue, vibration, and posture.