AH Anaesthesia Flashcards
(136 cards)
1
Q
What is ASA I classification?
A
Normal healthy animal
2
Q
What is ASA II classification?
A
Mild systemic disease
3
Q
What is ASA III classification?
A
systemic disease, well compensated or controlled by treatment
4
Q
What is ASA IV classification?
A
Severe uncompensated systemic disease
5
Q
What is ASA V classification?
A
Unlikely to survive 24 hours
6
Q
How long should cats fast for?
A
6-8 hours
7
Q
How long should dogs fast for?
A
8-10 hours
8
Q
How long should you fast rabbits for?
A
Dont need to - maybe 30 mins before
9
Q
What is anaesthesia?
A
Reversible production of a state of unconsciousness
10
Q
What is regional anaesthesia?
A
Lack of sensation caused by interruption of sensory nerve conduction in any region of the body
11
Q
What is sedation?
A
Allaying of irritability or excitement
12
Q
What is analgesia?
A
Reduced sensibility to pain
13
Q
What is narcosis/hypnosis?
A
Sleep like state
14
Q
What is the sequence of events of anaesthesia?
A
Owner conversation/consent Pre-op exam Check list/ASA classification Premedication Induction Maintenance Recovery and post-op care
15
Q
What is the anaesthesia triad?
A
Narcosis
Analgesia
Muscle relaxation
16
Q
What breed specific problem do boxers have relating to anaesthesia?
A
Cant have ACP (acepromazine)
17
Q
What breed specific problem do collies have relating to anaesthesia?
A
Multiple drug resistance gene - drugs build up in brain
Ivermectin
Butorphanol
Acepromazine
18
Q
What breed specific problems do greyhounds have relating to anaesthesia?
A
Low body fat and lack cytochrome P450 so need to use low dose
19
Q
What breed specific problem do dobermanns have relating to anaesthesia?
A
Von Willebrand factor
20
Q
What drugs are in schedule 2 of the misuse of drugs act?
A
Full mu agonists
eg. morphine, ketamine
21
Q
What drugs are in schedule 4 of the misuse of drugs act?
A
Benzodiazepines
22
Q
What are the two options for induction of anaesthesia?
A
Injectable anaesthesia
Inhalant anaesthesia
23
Q
What is are the two main IV injectable induction agents?
A
Propofol
Alfaxalone
24
Q
What is the murphy’s eye?
A
Safety hole in an endotracheal tube
25
What are the two different types of cuffs?
Low volume high pressure
| High volume low pressure
26
Which type of cuff is the best?
High volume low pressure - square, pressure spread over a larger SA
27
What is a V GEL used for?
Rabbits
28
What is the pilot balloon?
Small tube that allows us to inflate and deflate the cuff inside
29
What is the cuff for?
Prevents gas leaking - tight seal in trachea
30
How long should an endotracheal tube be?
Incisors to shoulder tip - not too long as increases deadspace
31
What is a species consideration in endotracheal intubation?
Local anaesthetic in cats - laryngospasm
32
Best way to confirm correct endotracheal tube placement?
Capnograph trace
| Then condensation in tube
33
What is the cylinder yolk?
Supports the cylinder, prevents wrong cylinder being attached
34
What system is used to prevent the cylinder being attached to the wrong inlet?
Pin index safety system - two protruding pins
35
What is the name of the seal in the cylinder yolk?
Bodok seal
36
What colour pipe signifies oxygen?
White
37
What colour pipe signifies nitrous?
Blue
38
What colour pipe signifies medical air?
Black with white collar
39
What is the name of the connection which prevent the wrong pipeline being attached?
Schrader sockets and schrader probe - wall
| Non-interchangeable screw thread (NIST) - machine
40
What stops hypoxia happening with nitrous oxide?
Hypoxic guard
| O2 failure alarm
41
What is the check valve?
Prevents backflow of gas to the machine - protects the machine from too much pressure
42
What measures the flow of gas?
Flowmeter
43
What is the minimum flow of O2?
200-300mL/min
44
What are the three parts of the flowmeter?
Flow control valve
Transparent tube
Floating bobbin/ball
45
What contains the volatile liquid anaesthetic agent?
Vaporiser
46
Where is the vaporiser located?
Downstream of the flowmeter
| On the back bar of the machine
47
Where do the two streams of gas go in the vaporiser?
The chamber above the liquid anaesthetic
The bypass channel
The ratio of gas can be adjusted
48
Where does the breathing system attach to on the machine?
The common gas outlet
49
What is scavenging?
Removal of environmental contaminants eg. anaesthetic gases
50
What are the two types of scavenging?
Active and passive
51
What is active scavenging?
Waste gases etc. are drawn outside of building by a fan and vent system
52
What is required for active scavenging?
An air break to prevent negative pressure to patients breathing system
53
What is passive scavenging?
Patients expiratory effort pushes gases out into tube going outside building or into a activated charcoal canister
54
How is oxygen supplied?
Liquid oxygen from a vacuum insulated evaporator - very cold
55
What are the two main maintenance inhalational agents?
Isoflurane
| Sevoflurane
56
What is the minimum alveolar concentration?
The effective dose that 50% of the population needs to prevent movement in response to pain
Helps determine potency of drugs
57
What does a high minimum alveolar concentration mean?
Low potency of volatile agent
58
What has an affect on the minimum alveolar concentration?
```
Hypothermia
Drugs
Pregnancy
Old age
Hypotension - low blood pressure
```
59
What has a higher blood solubility - iso or sevoflurane?
Isoflurane - longer to have effect and longer recovery as goes round in blood more but still good
60
What has a lower minimum alveolar concentration?
Isoflurane
61
Which is an irritant to mucous membranes - iso or sevo?
Isoflurane
| Sevo is non irritant so good for chamber induction of smallies
62
Do iso and sevo provide analgesia?
No
63
What effect does nitrous have on the body?
Good analgesic
64
What is the second gas effect from nitrous?
When the concentration gradient increases when there is more than one gas in the alveoli
65
What is diffusion hypoxia from nitrous?
Nitrous is very insoluble in blood rapidly diffuses back into the alveoli displacing O2 after nitrous is stopped
66
When are IM injections used for maintenance?
Quick procedures as they are difficult to control the depth, unpredictable and slow onset
67
What are the different types of IV maintenance?
Repeat IV injections - boluses
| TIVA - total intravenous anaesthesia - infusion
68
What does TIVA require?
Syringe drive/pump
| Technical skill - difficult calculations
69
How can heat be lost?
Convection
Conduction
Radiation
Evaporation
70
What stage of anaesthesia has 3 different planes?
Stage 3
71
What is the position of the eye in plane 1 and 2 of stage 3 of anaesthesia?
Ventromedial
72
What are the cranial nerve reflexes like in stage 2 of anaesthesia?
Present, may be hyperactive
73
What is stage 2 of anaesthesia?
Between onset of unconsciousness until rhythmic breathing
74
What is plane 1 of anaesthesia suitable for?
Minor procedures eg. skin suturing, lancing abcesses
75
What is present in plane 1 of anaesthesia?
Pinch reflex
| Palpebral reflex
76
What reflexes are present in plane 2 of anaesthesia?
Palpebral reflex barely
| Corneal reflex
77
What is the position of the eyeball in plane 3 of anaesthesia?
Central
78
What is the HR and BP like in plane 3 of anaesthesia?
Low
79
What procedures are plane 2 and 3 of anaesthesia suitable for?
All procedures
80
What is stage 4 of anaesthesia?
Overdose
81
What are the characteristics of stage 4 of anaesthesia?
```
Eye central swit hno palpebral reflex
Rapid/very slow weak pulse
Resp failure
Long capillary refill time
Twitching in the throat
```
82
What are some methods of monitoring anaesthesia without equipment?
```
Peripheral pulse
Resp rate
Eye position
Temperature
MM and CRT
```
83
What can be used to listen to the heart from inside the animal?
Oesophageal stethoscope
84
What does a palpebral reflex mean?
Anaesthesia is light
85
What do ventromedial eyes mean?
Adequate anaesthesia
86
What do central eyes mean?
If palpebral reflex present - light
| If no palpebral reflex present - deep
87
What is an arterial blood pressure measurement indicating?
Is an indirect indicator of blood flow
88
How do you measure blood pressure indirectly?
Doppler/oscillometric (cuff)
89
How do you measure blood pressure directly?
Catheter in artery
90
What is the best type of indirect arterial BP measurement?
Doppler
91
How is doppler different to oscillometric?
Only measures systolic, rather than both systolic and diastolic
92
What artery do you use for direct blood pressure monitoring?
Metatarsal/dorsal pedal artery
93
What does the doppler system use to detect blood pressure?
Ultrasonic signal which converts to an auditory signal depending on freq of RBCs
94
What does the direct blood pressure monitoring system use to detect BP?
Pressure waves in fluid filled tubing system
95
What drugs can affect blood pressure?
ACP
| Volatile gases - iso and sevo
96
What is the ideal blood pressure?
90mmhg systolic
97
How do you treat low blood pressure?
Reduce volatile agent and increase local blocks/analgesia
| Maybe fluids
98
What information does a capnograph give you?
Inspired CO2
Expired CO2
Respiratory rate
Capnograph - wave form
99
What should inspired CO2 be?
0
100
What are the two types of capnography?
Side stream
| Main stream
101
How does a side stream capnograph work?
Takes sample of expired air to analyse
102
What are the main advantages of side stream capnograph?
Cheaper, less likely to break
103
How does a main stream capnograph work?
Gas is analysed inside the connector using a infrared light source and a sensor
104
What are the pros and cons of main stream capnography?
Real time results
| Very expensive, easily damaged
105
What does the baseline of the capnograph trace represent?
The inspired gas - should be 0 CO2
106
What does the first angle in the capnograph trace represent?
Ventilation perfusion of the lungs
107
What does it mean if the first angle of the capnograph trace is greater than 90 degrees?
Ventilation perfusion mismath
108
What does the second angle of the capnograph trace assess?
Rebreathing
109
What does the flattening of the capnograph mean?
Alveolar plateau - last bit of the alveolar gas sample
110
What is the end tidal CO2 in dogs?
35-45mmhg
111
What could cause low end tidal CO2?
Hyperventilation - less CO2 build up
Low cardiac output
Hypothermia
Leak
112
What can cause a patient to rebreathe CO2 using a non-rebreathing system?
Too low fresh gas flow - CO2 not being pushed out of system
| Too much dead space
113
What can cause a patient to rebreathe CO2 using a rebreathing system?
Exhausted absorbent - soda lime
| Faulty/sticky valves
114
What info does ECG give you?
Heart rate - not CO tho
| ECG trace
115
Where are the ECG adhesive pads placed?
On paws
116
What are the colours of the ECG leads?
Red, yellow, green - traffic light
117
Where does each colour of ECG lead go on the animal?
Red - right fore
Yellow - left fore
Green/black - left hind
118
What does the P wave represent on an ECG?
Atrial depolarisation
119
What does the QRS complex represent on the ECG?
Ventricular depolarisation
120
What does the T wave represent on the ECG?
Ventricular repolarisation
121
What is a first degree block on an ECG?
Prolonged distance between P and R waves
| Signal is struggling to get through but does eventually
122
What is a second degree block on an ECG?
```
Beat stops (either randomly or progressively gets longer)
Intermittent passage through the AV node
```
123
What is a third degree block on an ECG?
Complete heart block, signal wont pass to AVN at all
124
What is different about a horse ECG?
QRS complex is negative - leads different places
125
What info does a pulse oximeter monitor?
Haemoglobin O2 saturation levels
| Pulse rate
126
Where does a pulse ox fit on the animal?
Tongue
127
How does a pulse ox monitor the oxyhaemoglobin?
Light emission/detector
| Oxyhaemoglobin absorbs more infrared light/less red light
128
What is not a good reading on a pulse ox?
95-90% - not great
| less than 90% - bad
129
What can be an issue with pulse ox?
Can give false readings
Pigmentation bad
Poor perfusion/anaemia
130
When should you deflate the cuff during recovery?
When close to extubation, not when you turn volatile agent off
131
When do you extubate dogs/rabbits?
When laryngeal reflexes return (swallowing)
132
When do you extubate cats?
Before laryngeal reflexes return - danger of laryngospasm
| Ear flick and blink reflexes
133
When do you do late extubation?
Brachycephalic
134
What should you monitor during recovery?
Temperature
Pulse
Respiration
135
What is a common issue in recovery?
Hypothermia
136
How do you monitor discomfort in recovery?
Composite pain scales
Grimace scales
Behavioural assessment
