Twitch transdiaphragmatic pressure depends critically on thoracoabdominal configuration.

Détails

ID Serval
serval:BIB_72C56123DE21
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Twitch transdiaphragmatic pressure depends critically on thoracoabdominal configuration.
Périodique
Journal of Applied Physiology
Auteur(s)
Chen R., Kayser B., Yan S., Macklem P.T.
ISSN
8750-7587 (Print)
ISSN-L
0161-7567
Statut éditorial
Publié
Date de publication
2000
Volume
88
Numéro
1
Pages
54-60
Langue
anglais
Résumé
We measured the effect of thoracoabdominal configuration on twitch transdiaphragmatic pressure (Pdi, t) in response to supramaximal, transcutaneous, bilateral phrenic nerve shocks in three thin normal men. Pdi, t was measured as a function of lung volume (VL) in the relaxation configuration, at functional residual capacity (FRC), and at the same end-tidal VL 1) during relaxation; 2) with the abdomen (Ab) expanded and the rib cage (RC) in its relaxed FRC configuration; 3) with RC expanded and Ab in its relaxed FRC configuration; and 4) in configuration 3 with an active transdiaphragmatic pressure similar to that required to produce configuration 2. In increasing VL from FRC to configuration 1, Pdi, t decreased by 3.6 cmH(2)O; to configuration 2 by 14.8 cmH(2)O; to configuration 3 by 3.7 cmH(2)O; and to configuration 4 by 2.7 cmH(2)O. We argue that changes in velocity of shortening and radius of curvature are unlikely to account for these effects and suggest that changes in diaphragmatic fiber length (L(di)) are primarily responsible. If so, equivolume displacements of Ab and RC change L(di) in a ratio of approximately 4:1. We conclude that Pdi, t is exquisitely sensitive to abdominal displacements that must be rigorously controlled if Pdi, t is to be used to assess diaphragmatic contractility.
Mots-clé
Abdomen/anatomy & histology, Abdomen/physiology, Adult, Diaphragm/cytology, Diaphragm/innervation, Elasticity, Electric Stimulation, Humans, Kinetics, Lung Volume Measurements, Male, Muscle Contraction, Muscle Fibers, Skeletal/physiology, Phrenic Nerve/physiology, Pressure, Ribs/anatomy & histology, Ribs/physiology, Tidal Volume
Pubmed
Web of science
Création de la notice
19/09/2013 10:58
Dernière modification de la notice
03/03/2018 18:18
Données d'usage