Estimating the diameter of airways susceptible for collapse using crackle sound

Arnab Majumdar, Zoltán Hantos, József Tolnai, Harikrishnan Parameswaran, Robert Tepper, Béla Suki

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Airways that collapse during deflation generate a crackle sound when they reopen during subsequent reinflation. Since each crackle is associated with the reopening of a collapsed airway, the likelihood of an airway to be a crackle source is identical to its vulnerability to collapse. To investigate this vulnerability of airways to collapse, crackles were recorded during the first inflation of six excised rabbit lungs from the collapsed state, and subsequent reinflations from 5, 2, 1, and 0 cmH2O end-expiratory pressure levels. We derived a relationship between the amplitude of a crackle sound at the trachea and the generation number (n) of the source airway where the crackle was generated. Using an asymmetrical tree model of the rabbit airways with elastic walls, airway vulnerability to collapse was also determined in terms of airway diameter D. During the reinflation from end-expiratory pressure = 0 cmH2O, the most vulnerable airways were estimated to be centered at n = 12 with a peak. Vulnerability in terms of D ranged between 0.1 and 1.3 mm, with a peak at 0.3 mm. During the inflation from the collapsed state, however, vulnerability was much less localized to a particular n or D, with maximum values of n = 8 and D = 0.75 mm. Numerical simulations using a tree model that incorporates airway opening and closing support these conclusions. Thus our results indicate that there are airways of a given range of diameters that can become unstable during deflation and vulnerable to collapse and subsequent injury.

Original languageEnglish
Pages (from-to)1504-1512
Number of pages9
JournalJournal of Applied Physiology
Volume107
Issue number5
DOIs
StatePublished - Nov 2009

Fingerprint

Respiratory Sounds
Economic Inflation
Rabbits
Pressure
Trachea
Lung
Wounds and Injuries

Keywords

  • Avalanche
  • Inflation
  • Pressure-volume curve
  • Trapped gas

ASJC Scopus subject areas

  • Physiology
  • Physiology (medical)

Cite this

Estimating the diameter of airways susceptible for collapse using crackle sound. / Majumdar, Arnab; Hantos, Zoltán; Tolnai, József; Parameswaran, Harikrishnan; Tepper, Robert; Suki, Béla.

In: Journal of Applied Physiology, Vol. 107, No. 5, 11.2009, p. 1504-1512.

Research output: Contribution to journalArticle

Majumdar, Arnab ; Hantos, Zoltán ; Tolnai, József ; Parameswaran, Harikrishnan ; Tepper, Robert ; Suki, Béla. / Estimating the diameter of airways susceptible for collapse using crackle sound. In: Journal of Applied Physiology. 2009 ; Vol. 107, No. 5. pp. 1504-1512.
@article{19f42c248a6d4507a984617334fd4d02,
title = "Estimating the diameter of airways susceptible for collapse using crackle sound",
abstract = "Airways that collapse during deflation generate a crackle sound when they reopen during subsequent reinflation. Since each crackle is associated with the reopening of a collapsed airway, the likelihood of an airway to be a crackle source is identical to its vulnerability to collapse. To investigate this vulnerability of airways to collapse, crackles were recorded during the first inflation of six excised rabbit lungs from the collapsed state, and subsequent reinflations from 5, 2, 1, and 0 cmH2O end-expiratory pressure levels. We derived a relationship between the amplitude of a crackle sound at the trachea and the generation number (n) of the source airway where the crackle was generated. Using an asymmetrical tree model of the rabbit airways with elastic walls, airway vulnerability to collapse was also determined in terms of airway diameter D. During the reinflation from end-expiratory pressure = 0 cmH2O, the most vulnerable airways were estimated to be centered at n = 12 with a peak. Vulnerability in terms of D ranged between 0.1 and 1.3 mm, with a peak at 0.3 mm. During the inflation from the collapsed state, however, vulnerability was much less localized to a particular n or D, with maximum values of n = 8 and D = 0.75 mm. Numerical simulations using a tree model that incorporates airway opening and closing support these conclusions. Thus our results indicate that there are airways of a given range of diameters that can become unstable during deflation and vulnerable to collapse and subsequent injury.",
keywords = "Avalanche, Inflation, Pressure-volume curve, Trapped gas",
author = "Arnab Majumdar and Zolt{\'a}n Hantos and J{\'o}zsef Tolnai and Harikrishnan Parameswaran and Robert Tepper and B{\'e}la Suki",
year = "2009",
month = "11",
doi = "10.1152/japplphysiol.91117.2008",
language = "English",
volume = "107",
pages = "1504--1512",
journal = "Journal of Applied Physiology",
issn = "8750-7587",
publisher = "American Physiological Society",
number = "5",

}

TY - JOUR

T1 - Estimating the diameter of airways susceptible for collapse using crackle sound

AU - Majumdar, Arnab

AU - Hantos, Zoltán

AU - Tolnai, József

AU - Parameswaran, Harikrishnan

AU - Tepper, Robert

AU - Suki, Béla

PY - 2009/11

Y1 - 2009/11

N2 - Airways that collapse during deflation generate a crackle sound when they reopen during subsequent reinflation. Since each crackle is associated with the reopening of a collapsed airway, the likelihood of an airway to be a crackle source is identical to its vulnerability to collapse. To investigate this vulnerability of airways to collapse, crackles were recorded during the first inflation of six excised rabbit lungs from the collapsed state, and subsequent reinflations from 5, 2, 1, and 0 cmH2O end-expiratory pressure levels. We derived a relationship between the amplitude of a crackle sound at the trachea and the generation number (n) of the source airway where the crackle was generated. Using an asymmetrical tree model of the rabbit airways with elastic walls, airway vulnerability to collapse was also determined in terms of airway diameter D. During the reinflation from end-expiratory pressure = 0 cmH2O, the most vulnerable airways were estimated to be centered at n = 12 with a peak. Vulnerability in terms of D ranged between 0.1 and 1.3 mm, with a peak at 0.3 mm. During the inflation from the collapsed state, however, vulnerability was much less localized to a particular n or D, with maximum values of n = 8 and D = 0.75 mm. Numerical simulations using a tree model that incorporates airway opening and closing support these conclusions. Thus our results indicate that there are airways of a given range of diameters that can become unstable during deflation and vulnerable to collapse and subsequent injury.

AB - Airways that collapse during deflation generate a crackle sound when they reopen during subsequent reinflation. Since each crackle is associated with the reopening of a collapsed airway, the likelihood of an airway to be a crackle source is identical to its vulnerability to collapse. To investigate this vulnerability of airways to collapse, crackles were recorded during the first inflation of six excised rabbit lungs from the collapsed state, and subsequent reinflations from 5, 2, 1, and 0 cmH2O end-expiratory pressure levels. We derived a relationship between the amplitude of a crackle sound at the trachea and the generation number (n) of the source airway where the crackle was generated. Using an asymmetrical tree model of the rabbit airways with elastic walls, airway vulnerability to collapse was also determined in terms of airway diameter D. During the reinflation from end-expiratory pressure = 0 cmH2O, the most vulnerable airways were estimated to be centered at n = 12 with a peak. Vulnerability in terms of D ranged between 0.1 and 1.3 mm, with a peak at 0.3 mm. During the inflation from the collapsed state, however, vulnerability was much less localized to a particular n or D, with maximum values of n = 8 and D = 0.75 mm. Numerical simulations using a tree model that incorporates airway opening and closing support these conclusions. Thus our results indicate that there are airways of a given range of diameters that can become unstable during deflation and vulnerable to collapse and subsequent injury.

KW - Avalanche

KW - Inflation

KW - Pressure-volume curve

KW - Trapped gas

UR - http://www.scopus.com/inward/record.url?scp=72749086025&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=72749086025&partnerID=8YFLogxK

U2 - 10.1152/japplphysiol.91117.2008

DO - 10.1152/japplphysiol.91117.2008

M3 - Article

VL - 107

SP - 1504

EP - 1512

JO - Journal of Applied Physiology

JF - Journal of Applied Physiology

SN - 8750-7587

IS - 5

ER -