Module 7

Question 1

Any material that has the ability to flow

Answer 1

fluid

Question 2

Hydrostatics definition

Answer 2

study of fluids that are not moving (density & pressure)

Question 3

Hydrodynamics definition

Answer 3

study of fluids in motion

Question 4

(T/F) Fluids can be either liquids or gases

Answer 4

True

Question 5

(T/F) Hydrostatic pressure does not depend on volume, container shape, or total mass

Answer 5

True

Question 6

(T/F) Hydrostatic pressure only depends on the depth of fluid, its density, and the acceleration of gravity

Answer 6

True

Question 7

Used to measure the specific gravity of liquids

Answer 7

hydrometer

Question 8

Smooth and orderly flow of fluid

Answer 8

laminar flow

Question 9

Chaotic and abruptly changing flow of fluid

Answer 9

Turbulent flow

Question 10

A mixture of laminar flow along the walls and turbulent flow in the center

Answer 10

Transitional flow

Question 11

volume of fluid that flows past a point per unit time

Answer 11

Flow rate

Question 12

SI unit for flow rate

Answer 12

m^3/s (cubic meters per second)

Question 13

In laminar flow, the flow velocity at the center is ____ times the velocity of the mean flow

Answer 13

2 times

Question 14

This type of flow predominates in the terminal bronchioles (smaller airways)

Answer 14

Laminar

Question 15

Blood flow is an example of ______ flow

Answer 15

laminar

Question 16

Large airway flow is an example of ______ flow

Answer 16

Turbulent

Question 17

Name 5 variables that can cause laminar flow to turn into turbulent flow

Answer 17

• increased velocity
• change in viscosity
• change in density
• change in diameter
• rough, irregular vessel walls
• kinked tubing angled >25 degrees
• medium to large airways
• coughing and phonation
• orifice constriction such as glottic closure

Question 18

As the speed of the fluid increases, the pressure of the fluid _______. This is explained by the _______ equation.

Answer 18

Decreases

Bernoulli equation

Question 19

The basis of the venturi effect when using venturi masks

Answer 19

Bernoulli equation - higher speeds = lower pressure

Question 20

Nebulizers use the ________ to deliver both humidification and medications such as albuterol.

Answer 20

venturi effect

Question 21

Explains the tendencies of fluid flow in a bifurcated tube after passing a constriction

Answer 21

Coanda effect

Question 22

During the coanda effect, the path with the _____ flow velocity will receive a higher volume of fluid or gas at the expense of the path with ______ flow velocity.

Answer 22

greater
lesser

(think about this almost like a vacuum. The faster velocity pathway will draw more of the fluid volume towards it)

Question 23

This law mathematically describes laminar flow

Answer 23

Poiseuille’s Law

Question 24

List the 4 components of Poiseuille’s Law

Answer 24

• Radius
• Viscosity
• Length
• Pressure

Question 25

This variable has the most dramatic effect on flow according to poiseuille's law

Answer 25

Radius

Question 26

Doubling the radius increases flow by ___ times

Answer 26

16

Question 27

Increased viscosity = ______ flow rate

Answer 27

decreased

Question 28

Increasing the radius = ______ flow rate

Answer 28

increased

Question 29

Increasing the length of tubing = ______ flow rate

Answer 29

decreased

Question 30

Increased pressure exerted on tubing = _____ flow rate

Answer 30

increased

Question 31

If tube length decreased by 1/2, then the flow rate increases by ____ times.

Answer 31

2 times

Question 32

This class of drug increases bronchial tube diameter, improving gas flow

Answer 32

B2 agonists

Question 33

Glottic closure & irregular wall or angles >25 degrees cause ______ flow in the medium to large airways

Answer 33

turbulent

Question 34

Increasing peak inspiratory pressures (PIPs) increases the pressure gradient, improving gas flow and tidal volume (Vt). However, this increases the risk of what?

Answer 34

converting laminar flow to turbulent flow

Question 35

Determines the presence of laminar, transitional, or turbulent flow

Answer 35

Reynold's number

Question 36

Re

Answer 36

Reynold's number

Question 37

Reynold's number equation incorporates factors of Poiseuille's Law and fluid ______

Answer 37

density

Question 38

Reynold's number is ______ related to viscosity

Answer 38

inversely

Question 39

Re < or = 2000 reflects ______ flow

Answer 39

laminar

Question 40

Re >2000 reflects _____ flow

Answer 40

turbulent

Question 41

In status asthmaticus pts., the addition of helium (heliox) to the breathing gas results in a decrease in the _____ of the gas and increases flow through airways

Answer 41

density

Question 42

Describes the relationship of wall tension (T) to pressure (P) and radius (r) in cylinders and spheres

Answer 42

Law of LaPlace

Question 43

stress force exerted over a given area

Answer 43

Tension

Question 44

Law of LaPlace equation for cylinders (blood vessels, aneurysms, ventricles)

Answer 44

T = Pr

Question 45

Law of LaPlace equation for spheres (alveoli)

Answer 45

2T = Pr

Question 46

In cylinders, wall tension increases with ______ radius

Answer 46

increasing

Question 47

This law shows why smaller capillaries don't burst during periods of hypertension, whereas larger vessels and aneurysms may

Answer 47

Law of LaPlace

Question 48

Increased pressure = ______ tension

Answer 48

increased

Question 49

Increased wall tension at end diastole = _____ stroke volume

Answer 49

increased

Question 50

Without surfactant, _____ alveoli would collapse, as they would require higher pressure to open compared to _____ alveoli.

Answer 50

smaller | larger

Question 51

If surface tension was the same, pressure is ______ in smaller alveoli than larger alveoli

Answer 51

greater

Question 52

Lack of surfactant _____ wall tension

Answer 52

increases

Question 53

what is the equation used for total pressure calculations of fluids on the bottom of cylinders when given height, atmospheric pressure and density of the fluid?

Answer 53

P2 = P1 + pgh ``` P1 = atmospheric pressure (in Pa) p = density in kg/m3 g = gravity constant (9.81 m/s2) h = height in m ```