Breathing Systems Blueprint Flashcards
(113 cards)
1
Q
what are the 4 general principles of breathing systems
A
Resistance
Rebreathing
Compliance
Common Components
2
Q
what are the two types of resistance
A
laminar
turbulent
3
Q
what is the significance of resistance
A
it imposes strain and work of breathing (especially in patients that are independently breathing)
4
Q
changes in breathing are proportional to
A
changes in work of breathing
5
Q
what is the greater source of resistance in the breathing system
A
Tracheal tube
6
Q
is regards to resistance, what should the anesthesia provider aim to do
A
minimize resistance such as minimize
- CONNECTIONS
- Connectors
- kinks
7
Q
what is poiseulles law
A
the relationship between airway resistance and the diameter of the tube (viscosity flow rate / rate 4th)
8
Q
in laminar flow, where is flow the highest
A
middle/center of the tube, due to less friction
9
Q
in poiseulles law, airway resistance is
A
airway resistance is inversely proportionate to the radius to the 4th power
10
Q
with resistance, a change in pressure will
A
signify the resistance
11
Q
define turbulent flow
A
can be either GENERALIZED or LOCALIZED
–flow is going in multiple directions
12
Q
define laminar flow
A
flow is smooth and parallel to the walls of the tube (the more resistance, the slower gas delivery and less efficient)
13
Q
changes in direction such as sharp turns/bends will result in
A
increase resistance
14
Q
describe generalized turbulent flow
A
when the flow of gas through a tube exceeds a certain value called a CRITICAL FLOW RATE (basically the flow is bouncing completely around in the tube)
15
Q
describe localized turbulent flow
A
when gas flow is below the critical flow rate but encounters constrictions, curves, valves or an area of localized turbulence (basically the flow meets resistance d/t kink or connectors causing turbulence)
16
Q
turbulent flow will need _____ due to resistance
A
more PRESSURE
17
Q
what is the one factor that is more import in the formulas for laminar and turbulent
A
laminar: viscosity of gas
turbulent: gas density
18
Q
when considering resistance and the size of an ETT, the anesthesia provider should
A
use the minimal length with the maximal internal diameter
19
Q
give examples of how anesthesia providers can minimize resistance
A
- shorten circuit length
- minimize kinks, turns
- shorten length of tube and wider diameter
- minimize connections
- minimize the amount of VALVES
20
Q
when does resistance become excessive
A
when the patient cannot overcome it (you will not be able to deliver gas and more invasive ventilator modes will be have be implemented)
21
Q
what is compliance
A
- the measure of the change in volume / the change in pressure
- MEASURE OF DISTENSIBILITY (the amount of pressure needed to generate that volume to distend lungs)
22
Q
what are the most distensible components of the breathing system
A
> reservoir bag
>breathing tubes
23
Q
compliance plays a role in the determination of
A
TIDAL VOLUME (bc its an inverse relation, more compliance more volume and less compliance less volume)
24
Q
less compliance, ____ resistance and ___ volume
more compliance, _____ resistance
A
- more resistance and lesser volume
- less resistance and higher volume
- *inverse relationship**
25
what is rebreathing
inhale previously respired gases from which CO2 MAY or MAY NOT have been removed
26
rebreathing has a ______ relationship with fresh gas flow
inverse
- low FGF = more rebreathing
- high FGF = less rebreathing
27
rebreathing will ____ and the fresh gas flow _____
- increases
| - decreases
28
what are the three factors affecting rebreathing
1. Fresh gas flow
2. mechanical dead space
3. breathing system design
29
the volume in a breathing system that is occupied by gases that are rebreathed without any change in composition
mechanical dead space (ventilation without perfusion)
30
How can mechanical dead space be minimized
separating the inspiratory and expiratory gas streams as close to the patient as possible
31
anatomical dead space plus the alveolar dead space
physiological dead space
32
consists of the patients conducting airway down to the alveoli
anatomical dead space
33
the volume of the alveoli ventilated but not perfused
alveolar dead space
34
why do we want to decrease dead space
we cannot effectively change the composition of inhaled gas composition
35
if dead space is increased without exchange of gases what occurs
rebreathing will be increased b/c increase dead space will decrease oxygen amount, increase CO2, and decrease volatile agents
36
with no rebreathing, the composition of inspired gas is ______ to that of the fresh gas delivered
identical
37
what are the benefits of rebreathing
- heat and moisture retention
- altered inspired gas tensions
- decreases costs
- decrease risk of exposure to OR personnel
38
what may patients under anesthesia rebreathe
oxygen, nitrous, CO2, volatile agents
39
oxygen rebreathing alveolar gas will have a _____ inspired oxygen tension
reduced
40
what are the common components of the breathing system
1. connectors and adaptors
2. reservoir bag
3. breathing tubes- long circuits
4. ALP Valve "pop off valve"
5. PEEP
6. filters
41
connectors will increase _____
dead space
42
fitting intended to joint together two or more similar components
connectors
43
a specialized connector that establishes functional continuity between otherwise incompatible components
adaptors
44
Connectors and adaptors can be differentiated by
shape, component attached to, added feature (nipple), size and type of fitting
45
______ increase the number of areas disconnections can occur
connectors
46
Connectors add ______ if positioned between the breathing system and the patient
dead space
47
describe the shape and size of the connector of the reservoir bag
ellipsoidal
| 22mm female
48
what are the 2 purposes of a reservoir bag
1. to allow gas to accumulate during exhalation permitting rebreathing
2. to protect the patient from excessive pressure
49
the reservoir bag serves as a visual or tactile observation to monitor _____
spontaneous respirations
50
the reservoir bag is the most ____
distendible, it will protect the patient from EXCESS PRESSURE
51
what is the standard set by the American society for testing and material (ASTM) for reservoir bags
<>1.5L bag (the pressure should 30-50 cm H2O)
<>bags larger than 1.5L (pressure should be 35-60 cm H2O)
<> typically a 3L is used in adults
52
the reservoir bag must be able to distend how many times its normal capacity
4X
| assess bags compliance when performing machine checkout
53
breathing tubes are large bore _____ tubing, which provides ____ and _____
CORREGATED
| flexibility and low resistance
54
what is the purpose of corrugated tubing in breathing tubes
prevents kinking and increases flexibility
55
_____ is an adjustable valve used to release gases to a scavenging system
APL valve "spill valve" "pop off valve" "pressure relief valve"
56
what is the purpose of the APL valve
to control the pressure in the breathing system
57
PEEP valves can be
unidirectional or bidirectional
58
what type of PEEP valves are primarily used today
BIDIRECTIONAL (these valves have a second flow channel with its own one way valve)
59
where should the PEEP valve be located
between the ventilator and breathing system
60
PEEP valves are marked with an arrow to display
the proper direction of gas flow (can also be marked with inlet and outlet arrow)
61
using PEEP in a spontaneously breathing patient will cause
an increase in work of breathing
62
what will occur if the PEEP valve is occluded
barotrauma
63
_____ is used to protect the patient from microorganisms and airborne particulate
filters
64
what are the benefits and downfalls of using a filter
Benefits: increases inspired humidity, increase rebreathing
Downfall: increases dead space, increase ETCO2
65
list the 4 classifications of breathing circuits
1. open
2. semi open
3. semi closed
4. closed
66
breathing circuits are classified by what two things
reservoir and rebreathing
| the only one that does not have a reservoir is open
67
give examples of an open breathing circuit and the classification
no reservoir and no rebreathing
| insufflation, open drop, NASAL CANULA or SIMPLE FACE MASK
68
give examples of an semi-open breathing circuit and the classification
has a reservoir and no rebreathing
| Mapleson (FGF > Minute Ventilation
69
give examples of an semi-closed breathing circuit and the classification
Has a reservoir and partial rebreathing
Circle system (FGF, APL)
( FGF < minute ventilation)
70
give examples of an closed breathing circuit and the classification
has a reservoir and complete rebreathing
CIRCLE SYSTEM (APL will be closed in this system)
( FGF VERY LOW)
71
what are the downfalls of using insufflation
1. ventilation is not well controlled d/t mask lacking direct contact with patients face
2. takes longer time to put child to sleep
3. entrained room air is breathed in rather than just gas
72
what open system is not utilized in anesthesia today
open drop (chloroform and either)
73
in the draw over technique, what is the carrier gas that would carry anesthetic agent to the patient through the cloth
ambient air
74
for a draw over open system, what is used at the carrier gas
ambient air
75
in a draw over system, spontaneous breathing room air is drawn over a vaporizer by
negative pressure while inhaling
76
in a draw over, the _____ bag encompasses a valve preventing retrograde flow which is then delivered to the patient via
self inflating bag (NOT THE SAME AS A RESERVOIR)
via nonrebreathing valve (AMBU)
77
in an open system, what happens to the CO2 the patient exhales
vented out to the room
78
what are the advantages and disadvantages of open systems
advantage:
- -simple, easy to use, not expensive
disadvantage:
- -cannot control inspired concentration b/c of entrained room air
- -cannot ASSIST ventilate patient b/c no reservoir bag
- -will not be able to conserve heat humidity (heat loss)
- -increases OR pollution
79
describe the characteristics of the mapelson systems
1. Absence of UNIDIRECTIONAL valves
2. No means to absorb exhales CO2 (fresh gas flow washes out the excess CO2)
3. not able to separate inspired and exhaled gases
4. monitoring CO2 is the best method to determine optimal FGF
80
what are the advantages of using a mapelson system
1. lightweight, simple, inexpensive
| 2. work of breathing is low and resistance is low d/t no valves being present)
81
in mapelsons, the lower FGF _____ and the higher FGF ______
lower (higher rebreathing)
| higher (lower rebreathing)
82
list the components of the mapelson system
1. FGF-inlet
2. APL
3. Reservoir bag
4. breathing tubes (Corrugated tubing)
5. face mask
83
list the ranking from best to worse (spontaneous)
A > DEF > CB
84
list the ranking from best to worse (controlled)
DEF > BC > A
85
what size is the breathing tube (corrugated) for mapelsons
22MM
86
in mapelsons, what is the biggest determinant of tidal volume
breathing tube (corrugated tubing)
87
what is the purpose of the APL valve in mapelsons
a spring/disk/valve
- - controls the flow of gas and allows for adjustment of pressure in circuit and system
- - can be used for manual or assisted breaths
88
when the ventilator is used, the APL valve is bypassed resorting to a
spill valve
89
what is the range for the APL valve
0 to 70 (totally open to totally closed)
90
as the APL valve is open or closed, what is exiting the breathing system
ONLY GAS
91
is the APL valve a unidirectional valve
NO - - it is an adjustable valve
92
since the reservoir bag is the most distensible, this can cause
volu or barotrauma
93
what is the ceiling effect for a reservior bag
2-3L bag options
if the bag is too full due to it being closed, it will divert gas and oxygen to scavenging system once it has reached this effect
94
what mapelsons can you not scavenge with
E (Arye T piece) because there is no reservoir bag present
95
what are the two components not present in mapelsons
no CO2 absorber and no unidirectional valves
96
_____ is the best method to determining the amount of FGF required to prevent rebreathing
ETCO2
97
list the advantages and disadvantages of mapelsons
Advantages:
- - less airway resistance
- - convenient
- - EASILY SCAVENGED
- - bain prevents heat loss
Disadvantages:
- - increases dead space and high FGF to prevent rebreathing
- - loss heat and humidity
- - inefficient use of inhaled agents
- - environmental pollution
- - unrecognized kinking in Bain Circuit
98
what is the primary benefit of Bain circuit
warms inhaled air (coaxial adjustment, which provided tubing inserted in the back of corrugated but ends close to the patient where FGF is released
99
what is the downfall of using bain
- kinking
| - at risk for hypercarbia
100
list the components of a circle system
1. Fresh Gas inlet
2. unidirectional Valves (inspiratory and expiratory)
3. Y-piece connector
4. APL valve
5. Reservoir bag
6. canister containing carbon dioxide absorbent
7. bag/vent selector switch
8. mechanical anesthesia ventilator
9. breathing tubes
101
if unidirectional valves become incompetent or jammed what will occur
incompetent: less resistance resulting in rebreathing
jammed: obstruction
102
the Y-piece connector is what size
15mm ETT and 22mm breathing tube
| dead space ends at y-piece
103
When is the APL valve open and closed
open: spontaneous breathing
closed: controlled ventilation
104
used to turn on when bagging a patient or off when the ventilator is in use
bag/vent selector switch
105
where is the most common area for disconnections to occur in the circle system
y-piece
106
list the arrangements of components for the circle system (9)
1. minimize absorbent desiccation (place FGF after your absorber to prevent wearing out absorber) leads to carbon monoxide formation
2. maximize FGF in the inspired mixture and maximum venting of alveolar gas
3. minimal consumption of absorbent (do not want to absorb the gases being vented through APL valve)
4. accurate reading from respirometer placed in the system
5. maximal humidification of inspired gas
6. minimal dead space
7. low resistance
8. minimal pull on ETT, LMA
9. convenience (tubes and wires should be organized)
107
what is the goal of the circle system
to minimize DEAD SPACE and MINIMIZE RESISTANCE
| NOT REBREATHING!
108
list the advantages of the circle system
- - Decreases OR pollution
- -heat moisture conserved
- -less FGF
- -LESS RESISTANCE
- -inspired concentration is fixed and constant
- -can be used in semi-open, semi-closed and closed system
109
list the disadvantages of the circle system
--INCREASES DEAD SPACE
--complex and not portable
--MISSED CONNECTIONS!
--malfunctioning unidirectional valves
stuck Open: rebreathing. stuck Closed: obstruction
110
the circle system prevents _____ rebreathing but permits rebreathing of _____
CO2 rebreathing
| permits anesthetic gases and oxygen rebreathing
111
in a closed breathing system, APL is _____ and what must the FG Flow be
APL closed
| --FGF must meet metabolic demand (150-250 ml/minute under anesthesia)
112
what is one Main benefit of a closed breathing system
Uses LOW FGF (d/t total rebreathing)
113
in a closed breathing system, during inspiration and expiration, where is the gas/O2 coming from
inspiration: FGF and some recycled gases from reservoir
expiration: fills reservoir and ALP then absorber
