Pulmonary

Question 1

Alveolar ventilation

Answer 1

VA= (VT-VD) f

VT= tidal volume 
VD= dead space
f= respiratory rate

Question 2

Forces acting on the lung system

Answer 2

Lung volume = recoil / compliance

Question 3

FRC

Answer 3

Functional residual capacity: neutral equilibrium point (2700)
Gas in the lungs at the end of a passive expiration

Represent the point where the outward chest wall recoil is counterbalance by the inward recoil of the lung

Question 4

Intrapleural pressure IPP

Answer 4

The outward recoil of the chest and inward recoil of the lung creates a negative (su atmospheric)

Question 5

Transmural pressure gradient PTM

Answer 5

Pressure across any tube or sphere

Calculate as inside pressure minus outside pressure

+ net force pushing out against the walls
- net force pushing in against the walls

Therefore lung can colapse if PTM is negative or zero

Question 6

Relation between intra pleural pressure and transmular pressure gradient

Answer 6

Relación inversa

Question 7

Compliance

Answer 7

Compliance=volume/pressure

Question 8

Lung compliance

Answer 8

Recoil (elasticity) is inversely proportional to compliance

Question 9

Airway resistance

Answer 9

Resistance = 1/radius 4