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1. COPD
 The third leading cause of death
 Progressive course
 No cure yet

2. Management Of COPD

3. Surgical Lung Volume Reduction
In LVRS, 20 percent to 35 percent of the most damaged
regions of each lung is removed, helping the remaining lung
to function better, thereby easing symptoms associated
with advanced emphysema

4. The mechanisms by which LVRS might provide benefit
1. reduces the size mismatching between the hyperinflated lungs and the
chest cavity,  increasing elastic recoil and improving expiratory airflow
2. Improvement in the mechanical function of the diaphragm and intercostal
muscles by decreasing the functional residual capacity
3. Improved left ventricular filling
4. Reduction in lung volumes during exercise (ie, reduced dynamic
hyperinflation), which is associated with reduced exertional dyspnea
Leading to :
• Improved forced expiratory volume in 1 second
• Improved gas transfer
• Improved exercise tolerance and quality of life

5. LVRS is contraindicated
in such patients
16% 0%
2.2%
0.2%
the 30-day mortality 2years, total mortality
Improvement in exercise capacity at 24 months compared with the post-rehabilitation
baseline
indications :
Age < 75 years
Severe dyspnea despite optimal medical therapy and maximal pulmonary
rehabilitation
> 6 months of smoking cessation
FEV1 < 45 % predicted and > 20%
(DLCO) that is NOT less than 20 % predicted
hyperinflation and heterogeneously distributed emphysema
( predominantly upper lung zone emphysema are more likely to benefit ).
Post-rehabilitation, a six-minute walk distance greater than 140 meters

6. Bronchoscopic Lung Volume Reduction

8. The beneficial effects following valve insertion have varied a lot but
include:
• Improved forced expiratory volume in 1 second
• Improved gas transfer
• Improved exercise tolerance and quality of life
• Reduction in dynamic hyperinflation.

9. Why should only a proportion of patients
develop atelectasis after valve insertion?
One possibility is simply  leaking valves
The other possibility is that variability in the amount of
collateral ventilation
IN OTHER WORDS , CV PREVENTS ATALECTASIS AND
IT’S THE MAIN CAUSE OF BLVR FAILURE

11. Definition :
“the ventilation of alveolar structures through passages or channels that
bypass the normal airways”
And these are :
•Inter-bronchiolar
•Inter-alveolar
•Bronchiolo-alveolar.
•Interlobar “ through
fissues “

12. What’s the significance of CV ?
The resistance to collateral flow in human lungs has been measured and found
to be 50 times greater than the resistance to flow through the normal airways.
It therefore seems that collateral ventilation has NO SIGNIFICANCE in subjects
with NORMAL AIRWAYS.
However, the resistance to collateral flow is markedly reduced certain
conditions including emphysema due to :
1. Destruction of terminal bronchioles  opening of CV
2. Significant expiratory airflow obstruction by “collapse + mucus plugging”
And This reduces Atalectasis and
improve Gas Exhange …………… how ??

13. In an area of lung that is completely obstructed, without collateral ventilation
alveolar gas tensions
within the obstructed
area rapidly equilibrate
with mixed venous
blood
no further gas exchange occurs alveolar gas is absorbed
 atelectasis develops
In an rea of complete obstruction with collateral ventilation
collateral ventilation can prevent atelectasis in the setting of airflow
obstruction and they found thagases t the PaO2 was higher and the
PaCO2 lower than concurrent arterial blood in the absence of CV
In other words, areas of lung that are only collaterally ventilated
can still carry out useful gas exchange—that is, collateral channels
allow obstructed areas to maintain a useful degree of function

14. Influence of parenchymal diseases on collateral
ventilation
Emphysema
The increase of FRC due to the loss of elastic recoil can also increase the size
of the collateral channels in emphysema
Fibrosis
collateral resistance increases in fibrotic segments because lung volume
decreases, and
because the collateral pathways are involved directly in the fibrotic process
Atelectasis
the poor collateral ventilation of the human middle lobe explains why
atelectasis of the middle lobe occurs after airways obstruction or infection

15. MEASURING COLLATERAL
VENTILATION

16. •Resistance can be measured
directly via a wedged bronchoscope
with selected bronchi occluded

17. collateral resistance may be
inferred from the
distribution of inhaled gas
during a single breath :
xenon and ventilation
scintigraphy
hyperpolarized helium MRI