Document Detail


Use of a triaxial magnetometer for respiratory measurements.
MedLine Citation:
PMID:  1864809     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
We describe a triaxial magnetometer (Tri-mag) system, which consists of a transmitter, four sensors, a processing unit, and a personal computer (PC). The Tri-mag processing unit outputs the position of each sensor relative to the transmitter in three orthogonal coordinates, and this information is communicated to the PC. First, we demonstrated that within a defined octant of a sphere in which the center is the transmitter, we can measure radial distances with an accuracy of +/- 1 mm over a range extending from 10 to 70 cm from the transmitter. Second, we recorded the three-dimensional movement of sensors on the anterior and posterior surfaces of the chest wall during maximum voluntary ventilation in four normal men; all sensors were placed in the midsagittal plane of the body. Anterior sensors were located on the sternum at the level of the third intercostal space and at 2 cm above the umbilicus, whereas posterior sensors were located on the posterior spine at the same vertical levels as the anterior sensors. In all subjects the following was found. 1) Both anterior sensors moved anterior and cephalad during inspiration. The anterior thoracic sensor showed greater vertical than anteroposterior (A-P) movement, whereas the anterior abdominal sensor showed greater A-P than vertical movement. 2) Inspiration was associated with spinal extension, whereas expiration was associated with spinal flexion. Third, we used Tri-mag information to 1) measure tidal volume (VT) over a range extending from 500 ml to inspiratory capacity and 2) measure the change in end-expiratory lung volume (EELV) over a range extending from FRC to FRC plus a minimum of 1.5 liters. Our results indicate that greater than 96% of the changes in VT and greater than 82% of the changes in EELV can be accounted for by changes in A-P, vertical, and lateral dimensions of the chest wall.
Authors:
S Levine; D Silage; D Henson; J Y Wang; J Krieg; J LaManca; S Levy
Related Documents :
9475359 - Computerised analysis of fetal behaviour.
3721039 - Animal models to study fetal behaviour.
6127249 - Automatic detection of fetal movement by doppler ultrasound during non-stress testing.
9493709 - Ultradian movements of shoots of two species of soybeans glycine soja (sieb. and zucc.)...
16326989 - Standardization of the pqrst waveform and analysis of arrhythmias in the fetus using ve...
15090929 - Botulinum toxin in a case of hemimasticatory spasm with severe worsening during pregnancy.
22672289 - Obstetric outcome in donor oocyte pregnancies: a matched-pair analysis.
23754329 - Male adiposity impairs clinical pregnancy rate by in vitro fertilization without affect...
16232179 - An outpatient regimen of combined oral mifepristone 400 mg and misoprostol 400 microg f...
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of applied physiology (Bethesda, Md. : 1985)     Volume:  70     ISSN:  8750-7587     ISO Abbreviation:  J. Appl. Physiol.     Publication Date:  1991 May 
Date Detail:
Created Date:  1991-09-09     Completed Date:  1991-09-09     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:  2311-21     Citation Subset:  IM    
Affiliation:
Pulmonary and Critical Care Section, Philadelphia Veterans Administration Medical Center, Pennsylvania.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adult
Evaluation Studies as Topic
Humans
Lung Volume Measurements / instrumentation
Magnetics / instrumentation*
Male
Middle Aged
Models, Biological
Respiratory Mechanics*
Respiratory Muscles / physiology
Tidal Volume

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


Previous Document:  Exercise training elevates RMR during moderate but not severe dietary restriction in obese male rats...
Next Document:  Effect of denervation or unweighting on GLUT-4 protein in rat soleus muscle.