| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 Respiratory Muscle
Laboratory,
The effect of stimulus frequency on the in vivo pressure generating capacity of the human diaphragm is unknown at lung volumes other than functional residual capacity. The transdiaphragmatic pressure (Pdi) produced by a pair of phrenic nerve stimuli may be viewed as the sum of the Pdi elicited by the first (T1 Pdi) and second (T2 Pdi) stimuli. We used bilateral anterior supramaximal magnetic phrenic nerve stimulation and a digital subtraction technique to obtain the T2 Pdi at interstimulus intervals of 999, 100, 50, 33, and 10 ms in eight normal subjects at lung volumes between residual volume and total lung capacity. The reduction in T2 Pdi that we observed as lung volume increased was greatest at long interstimulus intervals, whereas the T2 Pdi obtained with short interstimulus intervals remained relatively stable over the 50% of vital capacity around functional residual capacity. For all interstimulus intervals, the total pressure produced by the pair decreased as a function of increasing lung volume. These data demonstrate that, in the human diaphragm, hyperinflation has a disproportionately severe effect on the summation of pressure responses elicited by low-frequency stimulations; this effect is distinct from and additional to the known length-tension relationship.
hyperinflation; paired phrenic nerve stimuli
This article has been cited by other articles:
|
|
 |
|
  I. Vogiatzis, O. Georgiadou, I. Giannopoulou, M. Koskolou, S. Zakynthinos, K. Kostikas, E. Kosmas, H. Wagner, E. Peraki, A. Koutsoukou, et al. Effects of exercise-induced arterial hypoxaemia and work rate on diaphragmatic fatigue in highly trained endurance athletes J. Physiol., April 15, 2006; 572(2): 539 - 549. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W.D-C. Man, J. Moxham, and M.I. Polkey Magnetic stimulation for the measurement of respiratory and skeletal muscle function Eur. Respir. J., November 1, 2004; 24(5): 846 - 860. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. J. Rice, H. C. Nakayama, H. C. Haverkamp, D. F. Pegelow, J. B. Skatrud, and J. A. Dempsey Controlled versus Assisted Mechanical Ventilation Effects on Respiratory Motor Output in Sleeping Humans Am. J. Respir. Crit. Care Med., July 1, 2003; 168(1): 92 - 101. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G Dimitriou, A Greenough, L Pink, A McGhee, A Hickey, and G F Rafferty Effect of posture on oxygenation and respiratory muscle strength in convalescent infants Arch. Dis. Child. Fetal Neonatal Ed., May 1, 2002; 86(3): F147 - F150. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. Fauroux, J. Cordingley, N. Hart, A. Clement, J. Moxham, F. Lofaso, and M. I. Polkey Depression of Diaphragm Contractility by Nitrous Oxide in Humans Anesth. Analg., February 1, 2002; 94(2): 340 - 345. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G Dimitriou, A Greenough, A Endo, S Cherian, and G F Rafferty Prediction of extubation failure in preterm infants Arch. Dis. Child. Fetal Neonatal Ed., January 1, 2002; 86(1): F32 - 35. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. I. Polkey and J. Moxham Clinical Aspects of Respiratory Muscle Dysfunction in the Critically Ill Chest, March 1, 2001; 119(3): 926 - 939. [Full Text] [PDF]
|
|
|
|
|
|
M. I. POLKEY, Y. LUO, R. GULERIA, C.-H. H. ÅRD, M. GREEN, and J. MOXHAM Functional Magnetic Stimulation of the Abdominal Muscles in Humans Am. J. Respir. Crit. Care Med., August 1, 1999; 160(2): 513 - 522. [Abstract] [Full Text]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
