14. Pulmonary vascular resistance Flashcards Preview

Respiratory > 14. Pulmonary vascular resistance > Flashcards

Flashcards in 14. Pulmonary vascular resistance Deck (10):
1

PVR

pulmonary vascular resitance

2

pulmonary vascular resistance ( PVR) - equation

( Ppulm arter - Pleft atrium )/ cardiac output

3

resistance - equation

(8 x viscosity x vessel length) / πr4

4

pulmonary circulation resistance - low or high

low

5

pulmonary circulation - compliance - low or high

high

6

• How is pulmonary vascular resistance calculated?

PVR = pressure in the pulmonary artery - pressure in the left atrium)/cardiac output

7

• How is left atrial pressure measured?

It is approximated by pulmonary wedge pressure

8

• How do you measure pulmonary vascular resistance using flow and the difference in pressure across it?

R = ΔP/Q, where R is resistance, P is pressure, Q is flow

9

• Pulmonary vascular resistance is ____ (directly/inversely) related to vessel length and ____ (directly/inversely) related to vessel radius.

Directly; inversely—R = (8ηl)/(πr4), where η = viscosity of blood, l = vessel length, and r = vessel radius

10

• A patient's cardiac output is 5 L/min. Ppulm artery is 10 mmHg, & PL atrium is 5 mmHg. What is the pulmonary vascular resistance?

PVR = (Ppulm artery - PL atrium)/cardiac output = ([10 mmHg - 5 mmHg])/5 L/min) = 1 (mmHg × min)/L