Linked Life Data

6706781

Source:http://linkedlifedata.com/resource/pubmed/id/6706781

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1984-5-24
pubmed:abstractText
The use of sonomicrometry to study the mechanical properties of the diaphragm in vivo is presented. This method consists of the implantation of piezoelectric transducers between muscle fibers to measure the fibers' changes in length. Ultrasonic bursts are produced by one transducer upon electrical excitation and sensed by a second transducer placed 1-2 cm away. The time elapsed between the generation of the ultrasound burst and its detection is used to calculate the intertransducer distance. Excitation and sampling are done at 1.5 kHz and the output is a DC signal proportional to the length change between the transducers. Neither irreversible injury to the diaphragm nor regional differences within an anatomical part or segment were noted. Measurements were stable within the physiological range of temperature. We measured costal and crural length and velocity of contraction in anesthetized dogs during spontaneous breathing, occluded inspirations, passive lung inflation, and supramaximal phrenic nerve stimulation. We found that shortening during spontaneous breathing was 11 and 6% for crural and costal, respectively. The crural leads the costal in velocity of shortening. Supramaximal stimulation results in a velocity of shortening of 5 resting lengths X s-1. During an occluded inspiration crural shortens as much as in the nonoccluded breath, whereas costal shortens less. During passive lung inflation there is a nearly linear relationship between lung volume and diaphragm length; however, the relationships of chest wall dimensions with diaphragm length are nonlinear and cannot be described by any simple function. Some of the implications of these data on the present understanding of diaphragmatic mechanics are discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0161-7567
pubmed:author
pubmed:issnType
Print
pubmed:volume
56
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
753-64
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Respiratory muscle length measured by sonomicrometry.
pubmed:publicationType
Journal Article, Comparative Study, In Vitro, Research Support, Non-U.S. Gov't