Anesthesia Principles 613, Exam #2

Front 1

Boyle's Law

Back 1

Under constant temp, there is an inverse relationship b/t the volume and pressure for an ideal gas eg:squeezing ambu bag

Front 2

Charle's Law

Back 2

Under constant pressure, there is a direct relationship b/t volume and temp eg:inflatable cuff of LMA expands when placed in an autoclave

Front 3

Gay-Lussac Law

Back 3

At constant volume, the pressure of a fixed amt of gas is directly proportional to temp eg:as N2O cylinder empties, the pressure in the tank decreases even when N2O liquid is present
When full cylinder of gas is moved from outside temp 0*C to OR where temp is 20*C the pressure in the cylinder increases

Front 4

Dalton's Law

Back 4

The mixture of gases is the sum of their individual partial pressure must=total pressure eg: Pa+Pb+Pc=P total

Front 5

Fick's Law of Gas Diffusion

Back 5

Diffusion rate of gas is directly proportional to:
1. partial pressure gradient
2. membrane area
3. solubility of gas in membrane

Diffusion rate of gas is inversely proportional to:
1. membrane thickness
2. Square root of the molecular weight

Front 6

Graham's Law

Back 6

The rate at which gases diffuse is inversely proportional to the square root of the gram molecular weight
eg: release helium and oxygen in a closed room at the same time helium is smaller will achieve greater randomness faster
In short BIG molecules diffuse slower than smaller molecules

Front 7

Henry's Law

Back 7

The amt of gas dissolved in a liquid is directly proportional to the partial pressure of the gas over the liquid
eg: Coke bottle
AND indirectly proportinal to the temp eg: hypothermic pts remain anesthetized longer and febrile pts require more anesthetics

Front 8

Pouiseuilles's Law (FLOW)

Back 8

Flow is directly proportional to Radius
Double radius=increase flow x 16
Triple radius=increase flow x 81
Half radius=decrease flow by 1/16
Flow is directly proportional to hydrostatic pressure gradient
eg:raising IV pole increases hydrostatic pressure and increases flow to pt
Flow is inversley proportional to viscosity
eg: polycythemic pts blood has more viscosity so flow reduced
Anemic pts blood low voscosity increased flow
Flow inversely proprotinal to length
eg: reducing length by 1/2 increase flow x2 the orginal flow
BOTTOM LINE SHORT AND FAT IVS ARE THE BEST

Front 9

Pouiseuilles's Law (RESISTANCE)

Back 9

Resistance is inversely proportional to (r4) greater the radius the smaller the resistance
Resistance is directly proportional to viscosity greater blood viscosity the greater the resistance
Resistance is directly proportional to the tube length the longer the tube the greater the resistance
eg:Running unit of blood quickly with 16g(r4), pressure bag and add NS (decreasae viscosity)

Front 10

Bernoulli's Principle

Back 10

Flow through a constricted tube the velocity of flow increased and the lateral pressure on the walls of the tube decreases

Front 11

Venturi Effect and Bernoulli's Principle

Back 11

When fluid flows through a constricted region of a tube (Venturi tube) the velocity of flow increases and the lateral pressure(pressure by fluid on walls) decreases (Bernoulli effect)

Front 12

Laminar Flow

Back 12

Governed by Pouiseuilles's Law
The greater the inflow is on one side of the tube (pressure gradient) than the outflow pressure is on the opposite side of the tube the greater the flow
Radius has the most dramatic effect on flow
doubling radius results in 16 fold increase of flow
tripling radius results in 81 fold increase of flow
halving radius decreases flow by 1/16
Viscosity increased flow decreased
Length increased flow decreased

Front 13

Turbulent Flow

Back 13

Governed by Reynold's Number
flow changes from laminar to turbulent when reynold's number >2000
Results when molecules of a solution encounter the walls of the tube in a rough tumbling pattern, velocity of flow is high, kinks and bends exist in system, angle > 25 degrees, density of solution increased, radius of tube large,.
Turbulent flow occurs in medium to large airways

Front 14

Reynold's Number

Back 14

Directly proportinal to density of solution, linear velocity of flow ,tube diameter
Inversely to viscosity of fluid

Front 15

Squeezing amb bag

Back 15

Boyle's Law

Front 16

Inflatable cuff of LMA in autoclave
What law?

Back 16

Charle's Law
Volume and temp directly proportional
Pressure constant

Front 17

Full cylinder of gas outside in cold to warmer OR pressure in cylinder increases
What law?

Back 17

Gay-Lussac's Law
Pressure and temp directly proportional
Volume constant

Front 18

Coke Bottle
Hypothermic pts remain anesthetized
Hyperthermic(febrile)pts require more anesthetic
What law?

Back 18

Henry's Law

Front 19

Venturi Mask, nebulizer, jet ventilator
What law?

Back 19

Venturi Effect and Bernoulli's Principle

Front 20

Release of helium and oxygen at the same time in small room, helium achieves greater randomness faster
Big molecules diffuse slower than small molecules

Back 20

Grahams's Law
Duffusion rate of gas or liquid is inversely proportional to the square root of it's molecular weight