. Author manuscript; available in PMC: 2010 Sep 1.

Published in final edited form as: Clin Chest Med. 2009 Sep;30(3):495–viii. doi: 10.1016/j.ccm.2009.05.008

Table 1.

Changes in respiratory mechanics and pulmonary function tests in obesity

RESPIRATORY MECHANICS
Total respiratory compliance		Decreased
	Pulmonary (lung) compliance	Decreased
	Chest wall compliance	Decreased
Total respiratory resistance		Increased
	Airway resistance	Increased
	Additional pulmonary (lung) resistance	Increased
	Chest wall resistance	Increased or unchanged
PULMONARY FUNCTION TESTS
	FVC	Decreased or unchanged
	FEV1	Decreased or unchanged
	FEV1/FVC	Decreased or unchanged
	VC	Decreased or unchanged
	FRC	Decreased
	ERV	Decreased
	TLC	Decreased or unchanged
	D_LCO	Increased or unchanged

FVC = forced vital capacity; FEV1 = forced expiratory volume in one second; VC = vital capacity; FRC = functional residual capacity; ERV = expiratory reserve volume; TLC = total lung capacity; D_LCO = diffusion capacity for carbon monoxide