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Flashcards in Physics And Math Deck (82)
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1
Q

Molecular theory of matter

A

States that matter is made of minute particles called molecules that exists in liquid, solid, and gaseous states

2
Q

Kinetic theory of matter

A

Molecules are in constant random motion and have a degree of attraction between them called van der waals forces

3
Q

Critical temperature

A

Temp above which a gas cant be liquefied regardless of how much pressure is applied

4
Q

Avogadros hypothesis

A

If you have 2 diff containers containing 2 diff gases at same temp and pressure then they contain same number of molecules

5
Q

One mole is what

A

One gram multiplied by molecular weight

6
Q

One mole occupies what volume

A

22.4 l

7
Q

Calibration of vaporizers done using what

A

Avogadros hypothesis. Sevo weighs 200, so 200g sevo is 1 mol and occupies 22.4 l

8
Q

Bowles law

A

PV

9
Q

Charles law

A

V/T

10
Q

Bowles law

A

Volume of an ideal gas is inversely proportional to the pressure

V= 1/P

11
Q

Application of Boyles law

A

Reservoir bag. Applying pressure causes volume to decrease

12
Q

How boyles law applies to spontaneous breathing and bellows

A

When intrapulmonary pressure becomes negative, intrapulmonary volume increases

As pressure increases the volume in the bellows decreases

13
Q

Charles law

A

Volume is directly proportional to temperatiure.

V/T (kelvin)

14
Q

Gay lussacs law

A

At a constant volume the pressure of a gas sample is directly proportional to the kelvin temperature

15
Q

Application of gay lussacs law

Full cylinder moved from 70 to 100 degrees f. What happens to p

A

P increases

16
Q

Constants for the gas laws

A

Pressure, charles
Temperature, boyles
Volume, guy lussacs

17
Q

How ideal gas law applies to cylinders

A

As compressed gas empties, pressure falls. Cylinder has constant vol, the moles decreases as gas exits, so pressure decreases

18
Q

Daltons law

A

Total pressure of a gas in a mixture is the sum of the partial pressures of each gas

19
Q

Daltons law states that in a mix of gases the pressure of each is gas ____ as what it would exert if it alone occupied the container

A

Same

20
Q

What is ficks law of diffusion

A

rate of diffusion of substance across a membrane is r/t: concentration gradient, surface area of a membrane, solubility, thickness of membrane, molecular weight

21
Q
How diffusion r/t:
Concentration gradient
Surface area
Solubility 
Thickness of membrane 
Molecular weight
A
Directly 
Directly
Directly
Inversely 
Inversely
22
Q

Vgas=

A

Area x solubility x partial pressure difference
/
Molecular weight x distance

23
Q

Clinical applications of ficks law

A

2nd gas effect
Uptake of high vol n20 concentrates remaining 2nd gas
Diffusion hypoxia

24
Q

What is 2nd gas effect

A

High inspired conc of n20 accelerates uptake of a companion gas (ficks law)

25
Q

How ficks law r/t concentration

A

Uptake of high volumes of n20 concentrates the remaining 2nd gas

26
Q

Diffusion hypoxia

A

Diffusion of gases across the alveolo capillary membrane

27
Q

How ficks law r/t transfer of air pockets, ett cuff, and drug transfer

A
  1. When n20 in use, 34x more soluble in blood than n2, vol n20 in > than n out
  2. Ett cuff expands when n20 in use
  3. Placental transfer of drugs and o2
28
Q

Grahams law

A

A gas diffuses at a rate that’s inversely proportional to sq root of its molecular weight

29
Q

As molecular weight increases what happens to diffusion

A

Decreases

30
Q

What is Henry’s law

A

Amt of gas dissolved in a liquid is directly proportional to the partial pressure of the gas in contact w the solution

31
Q

Constants for co2 and o2

A
O2= .003 ml/100mlblood/mmHg partial pressure
CO2= .067ml/100mlblood/mmHg partial pressure
32
Q

How do you estimate pao2 using Henry’s law

A

Multiply fio2 by 5

33
Q

Critical temp

A

Temp above which a substance goes into gaseous form in spite of how much pressure is applied

34
Q

A gas cant be liquefied if ambient t is ___ than critical temp

A

Greater

35
Q

A gas can be liquified if sufficient ___ applied at ambient temp ___ the critical temp

A

Pressure, below

36
Q

Critical temp of 02

A

-119 degree c

37
Q

O2 cant be liquified at __ __ no matter how much pressure applied

A

Room temp

38
Q

A gas can be liquified if sufficient pressure applied at ambient temp ____ critical temp

A

Below

39
Q

Critical temp n20

A

39.5 degree c

40
Q

Temp of n20 at room temp

A

25 degree c

41
Q

Pressure ___ be applied to liquefy n2o at room temp

A

Can

42
Q

What is adiabatic cooling

A

Occurs when matter changes phase. Implies change in temp of matter w/o gain or loss of heat

43
Q

What applies to n20 cylinder regarding adiabatic cooling

A

When n20 opened fully frost can form at outlet due to cooling

44
Q

Joule thompson effect and example

A

Expansion of a gas causes cooling

As gas leaves a cylinder the expansion cools surrounding air causing condensation on cylinder

45
Q

What is poiseuilles law applied w laminar flow

A

Relationship of rate of flow and: pressure gradient across length of tube (direct), radius^4 of the tube (d), length of tube (inverse), viscosity of fluid (i)

46
Q

Poisuilles eqn

A
Q (flow) = pi x r^4 x change P
/
8 n (viscosity) x l (length of tube)
47
Q

What does poisuilles law apply to

A

Iv flow (large bore)
Airways (large ett_
Vascular flow (polycythemia and anemia)
Thorpe tubes- at low flows

48
Q

Viscosity

A

Determinant of flow when flow is laminar (low flow rate)

49
Q

How does density impact flow

A

When flow is turbulent. Density= mass/vol. determines rate of flow in flow meters when rate of gas flow high through variable orifice flow meter. Ex Helios

50
Q

How to calc reynolds number

A

Velocity x density x diameter
/
Viscosity

51
Q

When reynolds flow = turbulent

A

Greater than 2000

52
Q

Thorpe tube determinants

A

At low flows- annular orifice tubular- flow governed by viscosity

At high flows- wider top of float- more of an orifice- density governs flow

53
Q

Factors that change flow from laminar to turbulent

A

Increased velocity
Bend >20 degrees
Irregularity in tube

54
Q

Bernoullis theorem relates what

A

Pressure and velocity. Lateral wall pressure is least at pt of greatest constriction and speed is greatest.

Flow faster through constricted pts, slower at wider pts

55
Q

Narrow diameter= __ lateral wall pressure= __ speed

A

Decreased

Increased

56
Q

Wider diameter= __ lateral wall pressure = __ speed

A

Increased,

Decreased

57
Q

How bernoulli relates to venturi tubes

A

As fluid goes through narrow pts, velocity increases, pressure drops

Velocity of fluid can be found by measuring pressure

58
Q

3 ex of bernoulli in constricted tube with subatmospheric p and sidearm used to aspirate fluid

A

Nebulizers
Venturi o2 masks (24-40% o2)
Jet ventilation

59
Q

What is beers law

Beer part

A

Absorption of radiation by a given thickness of a solution of a given concentration is the same as 2x the thickness of a solution 1/2 the concentration (beer)

60
Q

What is lambert part of beers law

A

Each layer of equal thickness absorbs an equal fraction of the radiation that passes through it

61
Q

How pulse ox works

A

2 led lights. One red emits 660 nm light (detects deoxyhgb). One infrared emits light at 940 nm (oxyhgb). Measures absorption

62
Q

Errors in pulse ox

A

Artifact (ambient light, low perfusion, motion)
Alternate species of hgb (carboxy, etc)
Polycythemia (no effect)
Methylene and Isosulfan (false low)
Indocyanide green and indigo carmine (slight decrease)
Blue nail polish- low

63
Q
How carboxyhgb
Methgb
Hgbf 
Hgbs
Effect pulse ox
A

False high
Sat >85 false low, sat <85 false high
No effect
No effect

64
Q

Law of la place

A

Pressure gradient against wall of a sphere or tube/cylinder (vessel, ventricle, alveolus) r/t wall tension directly and radius inversely
T= pr

65
Q

Wall tension increases with vessel ___

A

Radius

66
Q

Applications of la places law

A
  1. Normal alveoli and need for surfactant in expiration
  2. Vascular pathology- aneurysm rupture d/t inc wall tension
  3. Ventricular vol and work of heart- dilated ventricle has more tension in wall (end diastolic p rises)
67
Q

Ohms law

A

Resistance that allows one ampere of current to flow under the influence of a potential of one volt
W (resistance)= volt (potential) / current (ampere)
Or e (volt)= i (amp/current) x r (resistance)

68
Q

Clinical applications of ohms law

A

Strain gauges in pressure transducers

Thermistors

69
Q

4 impacts of electricity in or

A
  1. Metal bed- bleeding- electrical equip- burn risk to pt
  2. Macro shock: current thru body from faulty wiring, improper grounding
  3. Microshock: current in or near heart from pacing wires or fault of equipment in cardiac cath
  4. Electrocautery
70
Q
Macroshock s/s from 
1 ma
5
10-20
50
100-300
6000
A
Skin tingling 
Max harmless current 
Let go source
Pain, loc, mechanical injury
V fib, resp intact 
Complete physiologic damage
71
Q

Microshock

50-100 ma leads to what

A

Vfib

72
Q
Macroshock 
Skin tingling 
Max harmless current 
Let go source
Pain, loc,mechanical injury 
V fib, resp intact 
Complete physiologic damage
A
1 ma 
5
10-20
50
100-300
6000
73
Q

Microshock

for vfib

A

50-100 micro amps

74
Q

How to calc
2% lidocaine
What it equals
How many mg per ml

A

2 gms in 100 ml

20 mg 1 ml

75
Q

1% lidocaine

1 ml= how many mg

A

1%= 1 gm per 100 ml
1000 mg in 100 ml
10 mg in 1 ml

76
Q

0.75 bupivicaine

How many mg in 1 ml

A

0.75 g per 100 ml
750 mg in 100 ml
7.5 mg in 1 ml

77
Q

Grams per __ c

1:100,000 epi

A

1 g

78
Q

1:100000 epi

Conc in 1 ml

A
1 g in 100000 ml 
1000 mg in 100000 ml
1 mg in 100 ml
1000 mcg in 100 ml 
10 mcg in 1 ml
79
Q

1:1000 neostigmine = what per ml

A

1 g 1000 ml
1000 mg in 1000 ml
1 mg per ml

80
Q

Epi 1:10,000

How many mg per ml

A
1 g in 10,000 ml 
1000 mg in 10,000 ml 
1 mg in 10 ml 
1000 mcg in 10 ml 
100 mcg per ml 
Or 0.1 mg per ml
81
Q

Epi 1:200,000

How to calc mcg per ml

A
1 g 200,000 ml 
1000 mg per 200,000 ml 
1 mg per 200 ml 
1000 mcg per 200 ml 
10 mcg per 2 ml 
5 mcg per ml
82
Q

2% lidocaine w epi 1:200,000

What is in each ml

A

2%= 2 g per 100 ml
2000 mg per 100 ml= 20 mg per ml

1:200,000 means 1 g per 200,000 ml. 5 mcg per ml