Exam 2 Basic Of Breathing Part 2

Front 1

Spontaneous ventilation depends on low resistance of light-weight mica discs

Back 1

Should be no more than 1.5 cmH2O

Front 2

Increased resistance occurs with
3 types

Back 2

Excessive moisture build-up
Electrostatic build-up
Heavier than normal disc

Front 3

Incompetent Expiratory Valve
Capnograph shows

Back 3

‘elevated baseline’
Baseline should always return to zero if you have no re-breathing
Re-breathing occurring on expiratory limb of waveform

Front 4

Incompetent Inspiratory Valve
Capnograph

Back 4

Capnograph shows abnormal ‘beta angle’
Normal beta angle approximately 90°
Re-breathing occurring during inspiration
Shows on inspiratory side of waveform
Shaded area represents approximately 180° beta

Front 5

Back 5

Capnograph shows ‘elevated baseline’
Baseline should always return to zero if you have no re-breathing
Re-breathing occurring on expiratory limb of waveform
Anatomic dead space exhaled at baseline
Also look at inspired CO2 numeric – FiCO2

Front 6

Back 6

Incompetent Inspiratory Valve

Capnograph shows abnormal ‘beta angle’
Normal beta angle approximately 90°
Re-breathing occurring during inspiration
Shows on inspiratory side of waveform
Shaded area represents approximately 180° beta

Front 7

Tubes of Breathing Circuit
corrugations

Back 7

to permit flexibility without kinking

Front 8

Tubes of Breathing Circuit
internal volume approx.

Back 8

internal volume approx. 400-500ml per meter

Front 9

Breathing Tubes Always test circuit pressure

Back 9

maintain 30 cm H2O pressure in circuit

Front 10

Longer tube =

Back 10

longer diffusion time

Front 11

Dead space is space in

Back 11

circuit occupied by gases that are rebreathed without any change in composition

Front 12

Dead space begins at

Back 12

Y piece and extends to any adaptors distal to Y piece (distal limb of Y piece and any ETT or mask between it and patient’s airway)

Front 13

Any increase in dead space should be accompanied by

Back 13

an increase in TV if alveolar ventilation is to remain unchanged (not usually clinically significant)

Front 14

Always put extension tubing at

Back 14

at inspiratory & expiratory check valves

Front 15

FGF entry point

Back 15

between absorber and inspiration valve

Front 16

FGF attachment to prevent detachment

Back 16

anti disconnect device

Front 17

3 functions Reservoir bag

Back 17

1. reservoir for anesthetic gases from which patient can inspire
2. provide visual/tactile means of existence and of volume of ventilation
3. serve as means for manual ventilation

Front 18

Adjustable Pressure-Limiting Valve (when open)

Back 18

fully open during spontaneous vent

Front 19

Adjustable Pressure-Limiting Valve
(partially closed with)

Back 19

partially closed during manual/assisted vent.
(until desired inspiratory press. is achieved)

Front 20

this allows reservoir bag to fill

Back 20

Adjustable Pressure-Limiting Valve
valve will open after bag has become distended during expiration
if valve open too much, bag won’t fill; if closed too much, rise in pressure could result in barotrauma (pneumothorax)
usually requires fine adjustments

Front 21

APL valves upper limit is

Back 21

70-80 cm H2O
can never be completely closed

Front 22

manometer

Back 22

1. always used to measure circuit pressure between expir./inspir. valves

2. usually reflects airway pressure if measured close to patient’s airway

Front 23

manometer rise in pressure may signal

Back 23

worsening pulmonary compliance; increase in TV; obstruction in circuit, tracheal tube or airway

Front 24

manometer drop in pressure
3

Back 24

1.indicate improvement in compliance;
2. decrease in TV;
3. leak in circuit

Front 25

Spirometers

Back 25

used to measure exhaled TV in circuit (usually near exhalation valve)
newer machines measure inspiratory TV near inspiratory valve
flow of gas across vanes within spirometer causes their rotation which is measured electronically

Front 26

Spirometers prone to error 3x

Back 26

inertia, friction, and water condensation

Front 27

when manual bagging do not push above

Back 27

20 cm, may go into the belly

Front 28

Heat and Humidity
4 points

Back 28

medical gas delivery systems supply dehumidified gases to circuit at room temp
high flows allow lower humidity, low flows allow greater water saturation
humidifiers are available
absorbent granules provide significant source of heat and humidity

Front 29

4 Disadvantages of circle system

Back 29

greater size
less portable
increased complexity, resulting in higher risk of disconnect or malfunction
increased resistance, difficulty of predicting inspired gas concentrations during low FGF’s

Front 30

Resuscitation Breathing Systems
AMBU bags or bag-valve-mask units
contains a_____________ (unlike a Mapleson or circle system)

Back 30

nonrebreathing valve
rebreathing is prevented by venting exhaled gas to atmosphere through exhalation ports

Front 31

BREATHING CIRCUITS
3 sizes
Manual Resuscitators

Back 31

adult, child and infant
adult-TV over 600ml
infant-TV 20-50 ml

Front 32

Manual Resuscitators intake valve in bag allows ___________ because it closes during compression

Back 32

PPV

Front 33

Manual Resuscitators and PEEP

Back 33

may connect a PEEP valve to expiratory port

Front 34

Manual Resuscitators
ASTM standard:

Back 34

capable of delivering at least 40% oxygen when connected to source supplying not more than 15 L/min

Front 35

Manual Resuscitators
3. Disadvantages

Back 35

1. require high FGF to achieve high FiO2
2. moisture in valves can cause them to stick
3. considerable loss of heat and humidity

Front 36

Patient Safety 2 errors

Back 36

breathing circuit disconnections and unintentional changes in gas flow

Front 37

FRESH GAS DECOUPLING
modern ventilators compensate

Back 37

delivered TV for the FGF

Front 38

with traditional ventilators, delivered TV is

Back 38

sum of volume delivered from vent and FGF during inspiratory phase


(if FGF increases, TV increases (significant in pediatrics)
if FGF decreases, TV decreases (increases ETCO2))

Front 39

ventilators that use fresh gas decoupling

Back 39

Drager Julian, Narkomed 600, Fabius GS

Front 40

fresh gas compensation
2 vents

Back 40

Aestiva and S/5 ADU

volume and flow sensors allow ventilator to adjust delivered TV so it matches set TV despite FGF

Front 41

1

Back 41

ventilator

Front 42

2

Back 42

APL bypass

Front 43

3

Back 43

APL valve

Front 44

4

Back 44

absorber

Front 45

5

Back 45

scavenger

Front 46

1

Back 46

to volume sensor

Front 47

2

Back 47

to oxygen sensor interface

Front 48

3

Back 48

expiratory valve

Front 49

4

Back 49

apl valve

Front 50

5

Back 50

fresh gas hose

Front 51

6

Back 51

absorber pole with scavenger terminal

Front 52

1

Back 52

expiration port

Front 53

2

Back 53

expiratory valve

Front 54

3

Back 54

peep max val connection port

Front 55

4

Back 55

selection knob for man and spont pressure limiting valve

Front 56

5

Back 56

APL bypass valve connection port

Front 57

6

Back 57

inspiratory valve

Front 58

7

Back 58

carbon dioxide absorber

Front 59

8

Back 59

inspiratory port

Front 60

9

Back 60

connector for breathing bag

Front 61

Closed Circuit Anesthesia
3 problems

Back 61

hypoxia or recall if nitrous is administered
induction is difficult

unpredictability of dosage of anesthesia for each patient
induction may be prolonged when using low flows

Front 62

Closed Circuit Anesthesia
once adequate depth is established

Back 62

there is little need for agent or nitrous oxide as they are rebreathed (O2 needs replenished due to its metabolism)

Front 63

Closed Circuit Anesthesia
open circuit every

Back 63

1-3 hours and run at higher flows for 5-10 min to washout nitrogen eliminate harmful substances

Front 64

Closed Circuit Anesthesia
not used frequently due to

Back 64

empirical calculations and fear of morbidity and mortality

Front 65

Insufflation
Complexity

Back 65

Very simple

Front 66

Insufflation
Control of anesthetic depth

Back 66

Poor

Front 67

Insufflation
Ability to scavenge

Back 67

Very poor

Front 68

Insufflation
Conservation of heat and humidity

Back 68

No

Front 69

Insufflation
Rebreathing of exhaled gases

Back 69

No

Front 70

Mapleson
Complexity

Back 70

Simple

Front 71

Mapleson
Control of anesthetic depth

Back 71

Variable

Front 72

Mapleson
Ability to scavenge

Back 72

Variable

Front 73

Mapleson
Conservation of heat and humidity

Back 73

No

Front 74

Mapleson
Rebreathing of exhaled gases

Back 74

No1
1These properties depend on the rate of fresh gas flow.

Front 75

Circle
Complexity

Back 75

Complex

Front 76

Circle
Control of anesthetic depth

Back 76

Good

Front 77

Circle
Ability to scavenge

Back 77

Good

Front 78

Circle
Conservation of heat and humidity

Back 78

Yes1
1These properties depend on the rate of fresh gas flow.

Front 79

Circle
Rebreathing of exhaled gases

Back 79

Yes1
1These properties depend on the rate of fresh gas flow.

Front 80

circle system from Mapleson

4 differences

Back 80

1. Inclusion of absorber canisters beneficial
2. Not necessary to use high flowrate
3. More economical to recycle mixed gases
4. Retention of heat and humidity

Front 81

When water dissociates or separates it forms

Back 81

H+ and OH-.

Front 82

When water dissociates or separates the process is known as

Back 82

process is known as ionization

Front 83

The hydrogen ion

Back 83

H+, has a positive charge because it lost an electron

Front 84

The hydroxide ion,

Back 84

OH-, has a negative charge due to its gaining an electron

Front 85

When another substance that ionizes is added

Back 85

acids and bases are formed

Front 86

An acid is created when

Back 86

when excess hydrogen ions are present

Front 87

A base is formed due to

Back 87

extra hydronium ions

Front 88

To determine if a substance is acidic or basic

Back 88

the pH should be determined.

Front 89

Neutralize CO2

Back 89

Granules Chemically
Chemical reaction between acid & base
Weak acid reacts with strong base

Front 90

CO2 + H2O =

Back 90

H2CO3
Carbonic acid

Front 91

Carbonic acid neutralized by

Back 91

base

Front 92

3 strong bases

Back 92

Sodium hydroxide
Potassium hydroxide
Calcium hydroxide

Front 93

Weak acid reacts with strong base
Products are

Back 93

carbonates, water & heat

Front 94

Acids are

Back 94

Substances produce H+ in aqueous solution
Proton donor

Front 95

Strong acids dissociate

Back 95

100% in water
Every molecule breaks apart
pH very low (0 – 3)

Front 96

Weak acids dissociates

Back 96

at lower %
Not every molecule breaks apart
pH closer to 7 (3 –6)
i.e.
Citric acid in lemons, acetic acid in vinegar

Front 97

Bases or Alkali are

Back 97

Substance produces OH- in aqueous solution

Able to accept an H+ (proton acceptor)

Front 98

Strong base dissociates

Back 98

100% in water
Every molecule breaks apart
High pH (10 –14)
Na, K & Ca hydroxides reactive & caustic to skin

Front 99

Weak base dissociates

Back 99

to lesser degree
Not every molecule breaks apart
pH closer to 7 (8 – 10)
Baking soda

Front 100

Minerals react w/ acid to form

Back 100

water & salt
Oxides, hydroxides & carbonates of metals

Front 101

Acid + Base =

Back 101

H2O + Salt

Front 102

Acid + Base reaction is always
(amount produced)

Back 102

Always exothermic
57.7 kj per mole H+

Front 103

Granules (metal hydroxides) are the

Back 103

base

Front 104

Carbon dioxide + water is

Back 104

carbonic acid

Front 105

Neutralization Reaction products are and adds

Back 105

Products are heat and water
Adds “heat and humidity”
Chemically absorbs carbon dioxide

Front 106

Required for chemical reaction (absorber)
3 parts required

Back 106

Patient’s carbon dioxide
Water in granules
Carbonic acid is acid for base to absorb

Front 107

Water ON & IN Granules
3 points

Back 107

Required for chemical reaction
Prevents agent absorption into granule
(If dry, pores open & more agent absorbed)
Percent water depends on formula

Front 108

USP requires Water (amount)

Back 108

14-19%
standard

Front 109

Baralyme (octahydrate) performs

Back 109

worse than Soda sorb when dry

Front 110

Requirements for CO2 Absorbers
3 points

Back 110

1 Should not be toxic itself or when mixed with inhalation agents
2 Low resistance to airflow
3 100% efficiency

Front 111

CARBON DIOXIDE ABSORPTION
4 points

Back 111

CO2 absorption makes rebreathing of exhalations possible
conserves agent and gases while preventing respiratory acidosis
rebreathing gas conserves heat & humidity
CO2 must be eliminated to prevent hypercapnia

Front 112

CARBON DIOXIDE ABSORPTION
and FGF

Back 112

FGF’s 0.3-0.5 L/min provide near-total rebreathing with full reliance on CO2 absorption
FGF’s greater than 4-5 L/min have little reliance on absorbent

Front 113

CO2 chemically combines with H2O to form

Back 113

carbonic acid

Front 114

CO2 absorbents contain

Back 114

hydroxide salts that neutralize carbonic acid

Front 115

H2CO3 + 2NaOH =

Back 115

Na2CO3 + 2H2O + heat (fast)
unstable compond
2nd equation not finished

Front 116

Na2CO3 + Ca(OH)2 =

Back 116

CaCO3 + 2NaOH (slow)
more stable compond
3rd and final