Collateral ventilation demonstrated by helium transfer

1969 ◽  
Vol 26 (3) ◽  
pp. 321-325 ◽  
Author(s):  
D. H. Baker ◽  
W. J. Daly
Keyword(s):  
Collateral Ventilation

Collateral ventilation and the sloping alveolar plateaus of He and SF6: A model study

1992 ◽  
Vol 90 (2) ◽  
pp. 145-158 ◽  
Author(s):  
D.P.J. Six ◽  
W.R. de Vries ◽  
S.C.M. Luijendijk
Keyword(s):  
Model Study ◽  
Collateral Ventilation

Interventional Bronchoscopy in the Management of Chronic Obstructive Lung Disease

2019 ◽  
Vol 15 (2) ◽  
pp. 133-139 ◽  
Author(s):  
Semra Bilaçeroğlu
Keyword(s):  
Management Strategies ◽  
Chronic Obstructive Lung Disease ◽  
Lifestyle Changes ◽  
Airflow Limitation ◽  
Chronic Obstructive ◽  
Interventional Bronchoscopy ◽  
Obstructive Pulmonary Disease ◽  
Mucosal Regeneration ◽  
Therapeutic Modalities ◽  
Collateral Ventilation

Background: Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation, hyperinflation and reduced gas exchange that lead to progressive dyspnea. Pulmonary rehabilitation, lifestyle changes, pharmacotherapy, long-term oxygen therapy, noninvasive ventilation and surgical therapeutic approaches are the basic management strategies. Purpose: In the last 15 years, various bronchoscopic therapeutic modalities have emerged for severe COPD. The aim of this review is to summarize the effects of these bronchoscopic treatments compared with lung rehabilitation and pharmacological therapies. Methods: A PubMed search for the eligible studies and reviews on interventional bronchoscopy and COPD has been conducted. Results: Bronchoscopic lung volume reduction (LVR) techniques are targeted to reduce hyperinflation. The efficacy of reversible valve implantation has been confirmed in several randomized controlled trials. It provides clinical benefit in the absence of interlobar collateral ventilation. Nonblocking bronchoscopic LVR with coils, thermal vapor or sealants is independent of collateral ventilation but has not been studied sufficiently. Partially irreversible coil implantation leads to parenchymal compression while irreversible LVR with thermal vapor or sealants induce an inflammatory reaction. Targeted lung denervation ablates parasympathetic pulmonary nerves in COPD for sustainable bronchodilation, and liquid nitrogen metered cryospray destroys hyperplastic goblet cells and excessive submucous glands in the central airways to induce mucosal regeneration in chronic bronchitis. Conclusion: The best-examined bronchoscopic LVR method is the valve therapy. The data from the other modalities are still limited. Further studies are required to select the patients that will optimally benefit from a particular treatment and to predict and treat the procedure-related complications.

Size of pores of Kohn: influence of transpulmonary and vascular pressures

1981 ◽  
Vol 51 (3) ◽  
pp. 739-745 ◽  
Author(s):  
R. W. Mazzone ◽  
S. Kornblau
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Pore Size ◽  
Minimum Diameter ◽  
Transmission Electron ◽  
Zone Ii ◽  
The Mean ◽  
Alveolar Septa ◽  
Collateral Ventilation

We investigated the influence of transpulmonary (Ptp) and vascular pressures on the size of the pores of Kohn in primary alveolar septa. Dogs lungs, perfused and ventilated in situ, were rapidly frozen with Freon 22 in zone II or III conditions following deflation to Ptp of 5, 15, or 25 cmH2O. Frozen samples were freeze-substituted for transmission electron microscopy. Five fields containing at least one pore each were selected randomly from each section of tissue, and the minimum diameter visible in the cut section was measured. For both zone II and III conditions, as Ptp increased, mean pore size increased. The mean pore size under zone III conditions was 1.2015, 1.788, and 2.249 micrometer for Ptp of 5, 15, and 25 cmH2O, respectively. For zone 2 conditions, the corresponding values were 1.1438, 1,8757, and 2.08 micrometer. For both zones II and III, increasing capillary hydrostatic pressure had no significant effect on pore size. The results support the notion that alveolar pores can increase collateral ventilation by dynamically stretching as Ptp increases. Capillary pressure does not influence pore size probably because of collagen fibers, which surround the pore lumen. Presumably, these fibers resist encroachment of capillaries on the pore lumen as vascular pressures increase.

scholarly journals SOME PHYSIOLOGIC AND PHARMACOLOGIC ASPECTS OF COLLATERAL VENTILATION

1965 ◽  
Vol 49 (6) ◽  
pp. 1015-1025 ◽  
Author(s):  
Edward P. Call ◽  
Gustaf E. Lindskog ◽  
Averill A. Liebow
Keyword(s):  
Collateral Ventilation

scholarly journals Collateral Ventilation to Congenital Hyperlucent Lung Lesions Assessed on Xenon-Enhanced Dynamic Dual-Energy CT: an Initial Experience

2011 ◽  
Vol 12 (1) ◽  
pp. 25 ◽  
Author(s):  
Hyun Woo Goo ◽  
Dong Hyun Yang ◽  
Namkug Kim ◽  
Seung Il Park ◽  
Dong Kwan Kim ◽  
...  
Keyword(s):  
Dual Energy ◽  
Dual Energy Ct ◽  
Initial Experience ◽  
Lung Lesions ◽  
Hyperlucent Lung ◽  
Collateral Ventilation

scholarly journals The dynamic nature of collateral ventilation

1970 ◽  
Vol 59 (4) ◽  
pp. 518-529 ◽  
Author(s):  
Chihsing Chen ◽  
Will C. Sealy ◽  
Anthony V. Seaber
Keyword(s):  
Dynamic Nature ◽  
Collateral Ventilation

Effects of methacholine and hypocapnia on airways and collateral ventilation in dogs

1979 ◽  
Vol 46 (5) ◽  
pp. 966-972 ◽  
Author(s):  
L. J. Smith ◽  
C. R. Inners ◽  
P. B. Terry ◽  
H. A. Menkes ◽  
R. J. Traystman
Keyword(s):  
Time Constant ◽  
Fiber Optic ◽  
Small Airways ◽  
Before And After ◽  
Airways Resistance ◽  
Lung Deflation ◽  
Collateral Ventilation

We studied the effects of hypocapnia and methacholine on small airways resistance (Rsaw) and collateral ventilation in anesthetized paralyzed dogs. The animals were ventilated with air while either 10% CO2 or air (hypocapnia) was infused through a segment obstructed with a fiber-optic bronchoscope. Measurements were made before and after instillation of methacholine into the obstructed segment. Collateral resistance (Rcoll) and Rsaw increased with hypocapnia and methacholine. The time constant for collateral ventilation increased with hypocapnia, but did not change with methacholine because of decreases in the compliance of the obstructed segment. We conclude that collateral channels respond to methacholine and hypocapnia in a manner similar to small airways and that local parasympathomimetic stimulation, unlike lung deflation does not increase the time constant for collateral ventilation.

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