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Old 10-18-2010
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Lungs query on lung physiology

what is radial traction on airways? and how will this be affected in restrictive and obstructive diseases of lung?
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Old 10-18-2010
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Because of the fibrotic nature of restrictive lung diseases, there's a radial traction on the walls of the bronchioles on expiration. This traction pulls on the walls of the bronchioles in a circumferential manner, in a direction opposite to the lumen, so they become dilated, increasing the forced expiratory volume (FEV1). This is why FEV1/FVC ratio is above 80% in restrictive lung diseases, although total lung capacity and residual volume are small.
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Quote:
Originally Posted by Haisook View Post
Because of the fibrotic nature of restrictive lung diseases, there's a radial traction on the walls of the bronchioles on expiration. This traction pulls on the walls of the bronchioles in a circumferential manner, in a direction opposite to the lumen, so they become dilated, increasing the forced expiratory volume (FEV1). This is why FEV1/FVC ratio is above 80% in restrictive lung diseases, although total lung capacity and residual volume are small.
why is this radial traction present in fibrosis??can u elaborate further and simplify it?
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