Length and curvature of the dog diaphragm

Aladin M. Boriek, Ben Black, Rolf Hubmayr, Theodore A. Wilson

Research output: Contribution to journalArticle

20 Citations (Scopus)

Abstract

Transdiaphragmatic pressure is a result of both tension in the muscles of the diaphragm and curvature of the muscles. As lung volume increases, the pressure-generating capability of the diaphragm decreases. Whether decrease in curvature contributes to the loss in transdiaphragmatic pressure and, if so, under what conditions it contributes are unknown. Here we report data on muscle length and curvature in the supine dog. Radiopaque markers were attached along muscle bundles in the midcostal region of the diaphragm in six beagle dogs of ∼8 kg, and marker locations were obtained from biplanar images at functional residual capacity (FRC), during spontaneous inspiratory efforts against a closed airway at lung volumes from FRC to total lung capacity, and during bilateral maximal phrenic nerve stimulation at the same lung volumes. Muscle length and curvature were obtained from these data. During spontaneous inspiratory efforts, muscle shortened by 15-40% of length at FRC, but curvature remained unchanged. During phrenic nerve stimulation, muscle shortened by 30 to nearly 50%, and, for shortening exceeding 52%, curvature appeared to decrease sharply. We conclude that diaphragm curvature is nearly constant during spontaneous breathing maneuvers in normal animals. However, we speculate that it is possible, if lung compliance were increased and the chest wall and the diameter of the diaphragm ring of insertion were enlarged, as in the case of chronic obstructive pulmonary disease, that decrease in diaphragm curvature could contribute to loss of diaphragm function.

Original languageEnglish (US)
Pages (from-to)794-798
Number of pages5
JournalJournal of Applied Physiology
Volume101
Issue number3
DOIs
StatePublished - 2006

Fingerprint

Diaphragm
Dogs
Functional Residual Capacity
Muscles
Phrenic Nerve
Pressure
Lung
Total Lung Capacity
Lung Compliance
Muscle Tonus
Thoracic Wall
Chronic Obstructive Pulmonary Disease
Respiration

Keywords

  • Chest wall
  • Mechanics
  • Respiration
  • Transdiaphragmatic pressure

ASJC Scopus subject areas

  • Endocrinology
  • Physiology
  • Orthopedics and Sports Medicine
  • Physical Therapy, Sports Therapy and Rehabilitation

Cite this

Boriek, A. M., Black, B., Hubmayr, R., & Wilson, T. A. (2006). Length and curvature of the dog diaphragm. Journal of Applied Physiology, 101(3), 794-798. https://doi.org/10.1152/japplphysiol.00865.2004

Length and curvature of the dog diaphragm. / Boriek, Aladin M.; Black, Ben; Hubmayr, Rolf; Wilson, Theodore A.

In: Journal of Applied Physiology, Vol. 101, No. 3, 2006, p. 794-798.

Research output: Contribution to journalArticle

Boriek, AM, Black, B, Hubmayr, R & Wilson, TA 2006, 'Length and curvature of the dog diaphragm', Journal of Applied Physiology, vol. 101, no. 3, pp. 794-798. https://doi.org/10.1152/japplphysiol.00865.2004
Boriek, Aladin M. ; Black, Ben ; Hubmayr, Rolf ; Wilson, Theodore A. / Length and curvature of the dog diaphragm. In: Journal of Applied Physiology. 2006 ; Vol. 101, No. 3. pp. 794-798.
@article{14e7e29630044239b9a85363f46c7eda,
title = "Length and curvature of the dog diaphragm",
abstract = "Transdiaphragmatic pressure is a result of both tension in the muscles of the diaphragm and curvature of the muscles. As lung volume increases, the pressure-generating capability of the diaphragm decreases. Whether decrease in curvature contributes to the loss in transdiaphragmatic pressure and, if so, under what conditions it contributes are unknown. Here we report data on muscle length and curvature in the supine dog. Radiopaque markers were attached along muscle bundles in the midcostal region of the diaphragm in six beagle dogs of ∼8 kg, and marker locations were obtained from biplanar images at functional residual capacity (FRC), during spontaneous inspiratory efforts against a closed airway at lung volumes from FRC to total lung capacity, and during bilateral maximal phrenic nerve stimulation at the same lung volumes. Muscle length and curvature were obtained from these data. During spontaneous inspiratory efforts, muscle shortened by 15-40{\%} of length at FRC, but curvature remained unchanged. During phrenic nerve stimulation, muscle shortened by 30 to nearly 50{\%}, and, for shortening exceeding 52{\%}, curvature appeared to decrease sharply. We conclude that diaphragm curvature is nearly constant during spontaneous breathing maneuvers in normal animals. However, we speculate that it is possible, if lung compliance were increased and the chest wall and the diameter of the diaphragm ring of insertion were enlarged, as in the case of chronic obstructive pulmonary disease, that decrease in diaphragm curvature could contribute to loss of diaphragm function.",
keywords = "Chest wall, Mechanics, Respiration, Transdiaphragmatic pressure",
author = "Boriek, {Aladin M.} and Ben Black and Rolf Hubmayr and Wilson, {Theodore A.}",
year = "2006",
doi = "10.1152/japplphysiol.00865.2004",
language = "English (US)",
volume = "101",
pages = "794--798",
journal = "Journal of Applied Physiology",
issn = "8750-7587",
publisher = "American Physiological Society",
number = "3",

}

TY - JOUR

T1 - Length and curvature of the dog diaphragm

AU - Boriek, Aladin M.

AU - Black, Ben

AU - Hubmayr, Rolf

AU - Wilson, Theodore A.

PY - 2006

Y1 - 2006

N2 - Transdiaphragmatic pressure is a result of both tension in the muscles of the diaphragm and curvature of the muscles. As lung volume increases, the pressure-generating capability of the diaphragm decreases. Whether decrease in curvature contributes to the loss in transdiaphragmatic pressure and, if so, under what conditions it contributes are unknown. Here we report data on muscle length and curvature in the supine dog. Radiopaque markers were attached along muscle bundles in the midcostal region of the diaphragm in six beagle dogs of ∼8 kg, and marker locations were obtained from biplanar images at functional residual capacity (FRC), during spontaneous inspiratory efforts against a closed airway at lung volumes from FRC to total lung capacity, and during bilateral maximal phrenic nerve stimulation at the same lung volumes. Muscle length and curvature were obtained from these data. During spontaneous inspiratory efforts, muscle shortened by 15-40% of length at FRC, but curvature remained unchanged. During phrenic nerve stimulation, muscle shortened by 30 to nearly 50%, and, for shortening exceeding 52%, curvature appeared to decrease sharply. We conclude that diaphragm curvature is nearly constant during spontaneous breathing maneuvers in normal animals. However, we speculate that it is possible, if lung compliance were increased and the chest wall and the diameter of the diaphragm ring of insertion were enlarged, as in the case of chronic obstructive pulmonary disease, that decrease in diaphragm curvature could contribute to loss of diaphragm function.

AB - Transdiaphragmatic pressure is a result of both tension in the muscles of the diaphragm and curvature of the muscles. As lung volume increases, the pressure-generating capability of the diaphragm decreases. Whether decrease in curvature contributes to the loss in transdiaphragmatic pressure and, if so, under what conditions it contributes are unknown. Here we report data on muscle length and curvature in the supine dog. Radiopaque markers were attached along muscle bundles in the midcostal region of the diaphragm in six beagle dogs of ∼8 kg, and marker locations were obtained from biplanar images at functional residual capacity (FRC), during spontaneous inspiratory efforts against a closed airway at lung volumes from FRC to total lung capacity, and during bilateral maximal phrenic nerve stimulation at the same lung volumes. Muscle length and curvature were obtained from these data. During spontaneous inspiratory efforts, muscle shortened by 15-40% of length at FRC, but curvature remained unchanged. During phrenic nerve stimulation, muscle shortened by 30 to nearly 50%, and, for shortening exceeding 52%, curvature appeared to decrease sharply. We conclude that diaphragm curvature is nearly constant during spontaneous breathing maneuvers in normal animals. However, we speculate that it is possible, if lung compliance were increased and the chest wall and the diameter of the diaphragm ring of insertion were enlarged, as in the case of chronic obstructive pulmonary disease, that decrease in diaphragm curvature could contribute to loss of diaphragm function.

KW - Chest wall

KW - Mechanics

KW - Respiration

KW - Transdiaphragmatic pressure

UR - http://www.scopus.com/inward/record.url?scp=33748472632&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33748472632&partnerID=8YFLogxK

U2 - 10.1152/japplphysiol.00865.2004

DO - 10.1152/japplphysiol.00865.2004

M3 - Article

C2 - 16902068

AN - SCOPUS:33748472632

VL - 101

SP - 794

EP - 798

JO - Journal of Applied Physiology

JF - Journal of Applied Physiology

SN - 8750-7587

IS - 3

ER -