Physiology Review Case Scenarios

Question 1

RC He Test in Obstructive Diseases

Answer 1

Might underestimate RC bc not absorbed well in diseased lung

Question 2

Fixed Upper Airway Obstruction

Answer 2

Problem with both insp and exp - flattening on both in flow-volume loop. Can be intra or extrathoracic

Question 3

Variable Extrathoracic Upper Airway Obstruction

Answer 3

Like loss of cartilage. Problem w/ insp (flattened), not exp bc P in airway decreases during insp and no cartilage to hold it open

Question 4

Variable Intrathoracic Upper Airway Obstruction

Answer 4

Problem w/ expiration (flattened), not insp

Question 5

Acute Acidosis/Alkalosis

Answer 5

For every acute 10 mmHg change in pCO2 there is a 0.07-0.08 pH change in opposite direction