Ventilation

Question 1

Define minute ventilation

Answer 1

Volume flowing into or out of the lungs in a minute. Includes alveolar ventilation.

Question 2

Define alveolar ventilation

Answer 2

Volume flowing into or out of the alveolar space in a minute.

Question 3

What are the five factors that influence ventilation?

Answer 3

1) Bronchodilators and constrictors (chemical effectors of resistance)
2) Exercise (meeting CO2 production demands)
3) Altitude (meet O2 demand)
4) Obstructive and restrictive diseases (alter compliance and resistance)
5) Gravity (regional differences)

Question 4

What factors make up work of breathing?

Answer 4

Respiratory rate and tidal volume. As part of tidal volume, compliance and resistance influence WOB.
Include work against elastic recoil and against resistance

Question 5

Define anatomic deadspace

Answer 5

Air that doesn’t reach the alveoli (remains in conducting pathways)

Question 6

Define alveolar deadspace

Answer 6

Alveoli that don’t participate in gas exchange despite ventilation (no perfusion)

Question 7

Define physiologic deadspace

Answer 7

The sum of anatomic and alveolar deadspace

Question 8

What is the PFT pattern in obstructive disease?

Answer 8

Low FEV/FVC
High FRC, RV
Increased resistance

Question 9

What is the PFT pattern in restrictive disease?

Answer 9

Slightly high FEV/FVC

Low TLC