Block 1 Flashcards
(500 cards)
1
Q
What is the physical status?
A
This is the assessment of systemic risk in relation to ASA standards
2
Q
What is level 1 ASA?
A
Healthy patient
3
Q
What is level 2 ASA
A
Patient with mild system disease
4
Q
What is level 3 ASA?
A
Severe systemic disease but well controlled
5
Q
What is level 4 ASA?
A
Severe systemic disease but threat to life
6
Q
What is level 5 ASA?
A
Not expected to live for more than 24h without intervention
7
Q
What is level 6 ASA?
A
Patient is being used for organ donation
8
Q
What do agonists do?
A
Activate that specific receptor
9
Q
What do antagonists do?
A
Block that specific ligand
10
Q
What are 4 mechanisms of action of acepromazine?
A
Blockade of dopamine receptors in forebrain
Serotonin antagonist (5-HT1, 5-HT2)
Blockade of alpha-1 adrenergic receptors in vasculature
Inhibitory effect on P-glycoproteins and alter uptake of other drugs into brain
11
Q
What a potential genetic issue with acepromazine?
A
Dogs with MDR1 mutation may increase toxicity due to ATP-binding transporters
12
Q
What is dopamine 1 receptor?
A
Post-synaptic and causes vasodilation of splenic and renal circulations
13
Q
What is dopamine 2 receptor?
A
Pre-synaptic and causes norepinephrine release
14
Q
What causes vasodilation with acepromazine?
A
alpha 1 adrenergic receptor blockade
15
Q
How long will vasodilation with acepromazine last?
A
Longer than the sedation because the alpha-1 receptor affinity is greater than the dopamine receptor affinity. So sad
16
Q
What is the horse penis side effect of acepromazine
A
Paraphimosis
17
Q
What kidney issue may occur due to acepromazine
A
Decreased systemic vascular resistance causes increased renal perfusion
18
Q
What happens with the spleen with acepromazine?
A
Splenic engorgement causing a decrease in PCV by 20-30%
19
Q
What happens with histamines with acepromazine?
A
Antihistaminic effect due to an H1 receptor blockage
20
Q
Where is acepromazine metabolized?
A
The liver
21
Q
Does acepromazine have analgesic effect?
A
No but can enhance analgesic effect of other drugs
22
Q
What happens to the muscles during acepromazine?
A
Muscle relaxant, may see 3rd eyelid prolapse
23
Q
How can you administer acepromazine?
A
Any way
24
Q
Is acepromazine reversible?
A
NOT REVERSIBLE!
25
What is the time to clinical effect of acepromazine IM and IV?
IM: 30min
IV: 10-15min
26
Is acepromazine an antiemetic?
Yes!
27
What are the 2 most common alpha-2 agonists?
Xylazine and dexmedotomine
28
What is the main mechanism of action of alpha 2
Bind to alpha 2 and 1 receptors in CNS and PNS
Activation causes hyper polarization of cells causing decreased cellular activity
29
What is the ligand for alpha 2?
norepinephrine
30
Which receptor specifically causes sedation and supra spinal analgesia for alpha 2 receptor?
Alpha 2A (maybe alpha 2D in certain species)
31
How are alpha 2 agonists metabolized?
Liver and excreted in urine
32
What are the 4 cardio effects of alpha 2 agonist?
Vasoconstriction and hypertension (alpha 2B) then vasodilation (alpha 2A)
Peripheral vasoconstriction (alpha 1 receptor)
HR decreases (baroreceptor reflex)
Decreased CO (30-50%)
33
What are 2 respiratory effects of alpha 2 agonists?
Decreased respiratory rate
Stridor or dyspnea from muscle relaxation
34
What are 2 musculoskeletal effects of alpha 2 agonist?
Great muscle relaxers
Base-wide stance in horses
35
What happens to salivation with alpha 2 agonists?
Decreased salivation but a suppressed swallow reflex (more saliva in mouth)
36
What happens to blood glucose with alpha 2 agonist?
Increased due to a suppression of insulin release
37
What are 2 urinary effects of alpha 2 agonists
Anti-ADH and decreased tubular reabsorption of sodium causing low urine specific gravity
Decreased renal perfusion due to vasoconstriction
38
What is the main contraindication of alpha 2 agonist?
Heart disease (vasoconstriction)
39
What is the ratio of tolazoline with alpha1:alpha2
1:1
40
What happens if you reverse tolazoline in a camelid
Death
41
How are alpha 2 agonists reversed?
With alpha 2 antagonists
42
What is the alpha 2 antagonist used for xylazine?
Yohimbine
43
What is the alpha 2 antagonist used for dexmeditomidine/
Atipamezole
44
Who is most and least sensitive to xylazine?
Most: Ruminants (100x)
Least: Pigs
45
What is a stronger alpha 2 agonist for horses?
Detomidine (dormosedan)
46
What are 5 main affects of benzodiazepines?
Sedation
Relaxation (anxiolytics)
Anticonvulsants
Muscle relaxant
Amnesia
47
What receptor do benzos work on?
GABA
48
What subunit does the sedative effects come from on the GABAa?
Alpha-a
49
What subunit does the anxiolytic effects come from on the GABAa?
Alpha-b
50
What subunit does the muscle relaxation effect come from on the GABAa?
Either a or b
51
Which benzodiazepine has a shorter onset and a more potent effect due to greater affinity for receptor?
Midazolam
52
Which benzo is more lipid soluble?
Diazepam (brain?)
53
How is midazolam metabolized?
hepatic, intestinal
54
Is midazolam excretion affected by renal failure?
NO!
55
How is diazepam metabolized?
Hepatic (excreted in urine)
56
What is the toxicity associated with diazepam?
Long term use of diazepam has seen hepatic necrosis
57
What are the cardiovascular effects using benzodiazepines
None
58
What are the respiratory effects using benzodiazepines
Depression of swallow reflex
59
What are the musculoskeletal effects using benzodiazepines
Muscle relaxation
60
What are the GI effects using benzodiazepines
appetite stimulant in cats and goats
delayed gastric emptying in cats
61
What behavioral thing can be seen in benzodiazepines?
Paradoxical effect - excitement
62
Is there analgesia with benzodiazepines?
No!!!
63
What is the reversal (antagonist) for benzodiazepines
Flumazenil
64
How is flumazenil metabolized?
Hepatic
65
How can you administer midazolam?
IV, IM, or PO
66
How can you administer diazepam?
IV or PO
67
What is neuroleptanalgesia
Combination of an opioid with a sedative or tranquilizer
68
What is the benefit of neuroleptanalgesia?
Increase sedative and analgesic effect
Decrease dosage of both
69
What is the main effect of opioids?
Analgesia
70
What are the 2 opioid receptors?
Mu and Kappa
71
What are the 4 classifications of opioids?
Opioid agonists
Opioid partial agonists
Opioid agonist-antagonist
Opioid Antagonist
72
What classification of opioids stimulate all types of receptors?
Opioid agonists and partial agonists
73
What classifications of opioid receptors stimulate some receptors and block others?
Opioid agonist-antagonists
74
What classification of opioid receptors block all receptors?
Opioid antagonists
75
What are 4 opioid agonists?
Fentanyl
Hydromorphone
Morphine
Methadone
76
Of the full agonists, which one is not used for premed because it is short acting?
Fentanyl
77
Which opioid classification provides the highest level of analgesia but also the highest incidence of side effects?
Full agonists
78
How long does fentanyl last?
20 minutes
79
How long do other full agonists last?
3-4 hours
80
Why do partial agonists last longer?
Bind very tightly to mu receptor causing longer lasting effects
81
How long does buprenorphine last?
6-8 hour (roughly 2x as long as full)
82
What are the receptors of a agonist/antagonist?
Kappa agonist / Mu antagonist
83
What is the length of kappa/mu?
Short duration (1-2h)
84
What species are kappa/mu usually used in?
Large animal
85
What happens to full agonist with kappa/mu?
Bind tightly to mu receptor and will reverse full mu agonist (because its an antagonist)
86
What are some side effects to dogs on opioids?
Miotic pupils, hypothermia, dysphoria
87
What are some side effects to cats on opioids?
Dysphoria, hyperthermia
88
What are some side effects to horses on opioids?
Stall pacing, dysphoria
89
What are the 4 opioid agonists?
Morphine
Hydromorphone
Fentanyl
Methadone
90
What is the relevant partial agonist?
Buprenorphine
91
What is the relevant opioid agonist-antagonist?
Butorphanol
92
What is the relevant opioid antagonist?
Naloxone
93
What is the main effect of opioids on the cardiovascular system?
Bradycardia
Blood pressure
94
How to reduce bradycardia associated with opioids?
Anticholinergics
95
What causes some blood pressure decreases with opioids?
Morphine causes histamine release resulting vasodilation
96
What is the respiratory affect of opioids?
Depressed, primarily if animal is unconscious (rate and tidal volume)
97
Why do opioids reduce respiratory function?
Higher paCO2 is tolerated before respiration is increased
Cough is suppressed
98
What are 3 very important GI affects of opioids?
Increased salivation
Emetic (except methadone)
GI slows down -> ileus
99
Why should you use caution with opioids in horses?
Since GI slows down, increase chance of colic
100
What is the main effect of opioids on urinary system?
Increased release of ADH causing a decrease in urination
101
How are opioids metabolized?
In the liver
102
What are 2 benefits of a partial agonist or a agonist-antagonist?
Less addictive
Less hard on cardiopulmonary system
103
What does a partial agonist or agonist-antagonist look like?
Analgesia remains but sedation is lessened and cardiopulmonary depression is lessened
104
What happens when an opioid antagonist is given?
Sedation is reversed but analgesia remains
105
Rank ace, alpha 2 agonist, and bentos in order of how much sedation you expect to be given
#1 alpha 2
#2 Benzo
#3 Ace
106
Of the sedatives, dex and xylazine produce the highest level of sedation
107
What is the purpose of neuroleptanalgesia?
Mix a sedation with a tranquilizer
108
When is the use of epidural opioids an option?
When the patient is inpatient
109
What is the best opioid to use for epidurals?
Preservative free morphine
110
How long does a opioid epidural take to kick in?
1-2 hours
111
How long with an opioid epidural last?
8-12 hours
112
Where is the epidural in a small animal placed and what are the landmarks?
Between L7 and S1
Between ileal wings
113
What species is Zorbium used in?
Cats!
114
What are the 4 things that anesthesia can be used for?
Surgery
Diagnostics
Long term ICU ventilation
Physical exam if needed
115
What is the anesthesia triad?
Muscle relaxation
Unconsciousnes
Analgesia
116
What are the 3 big things to be assessed prior to anesthesia?
Cardio
Pulmonary
CNS
117
What are 2nd tier things to be assessed for anesthesia?
Renal and hepatic
118
What is the minimum required at OSU CVM before put under general anesthesia?
PCV TP
119
What are the 6 components to anesthetic plan?
physical exam
premed
induction
maintenance
monitoring
recovery
120
What are the 3 reasons to premed?
Easier induction
Easier placement of IV catheter
Smoother recovery
121
Remember:
Ace is not reversible
Dex is reversible
Ace increases blood flow to kidneys
Ace is dose dependent
122
Remember:
Ace is a vasodilator
Dex is a vasoconstrictor
Dex provides analgesia
Dex increases sedation level
123
Remember:
In horses, xylazine lowers head. Detomadine is a great premed in them
Ace is a muscle relaxer, dex is an emetic
In dogs with heart disease, dont use drugs that cause bradycardia (opioids and alpha 2)
124
What premed drugs can cause bradycardia?
Opioids and alpha 2
125
What do you see in older patients in terms of dosing?
Less drug needed
126
What is different about greyhound pre med?
Take longer to wake up
Lower heart rate so don't use drugs that will decrease HR too much
127
What is the most common drug sedative to cause hypoventilation?
Alpha 2
128
What is the most common drug sedative to cause hypotension?
Ace
129
What drug should you avoid if you are worried about histamine release?
Morphine (histamine release)W
130
what is an additional anesthetic concern with horses under general?
Hypoxemia
131
Remember when using a full mu agonist with horses (morphine), it will slow GI and may cause colic
Reminder:
Methadone is not an opioid emetic, good for patients at risk of vomiting
132
When should you throw away a propofol bottle?
6-12 hours after opening
133
What channels does propofol work on?
GABA receptor (same as benzos and same mechanism I think)
134
How long does propofol last?
5-15 min
135
How is propofol metabolized
Both hepatic and extra hepatic
136
How can you infuse propofol?
IV ONLY
137
How can you decrease side effects with propofol?
Injection over a long period of time
138
What is another way you can use propofol for total IV anesthesia?
CRI IV
139
What are the 4 cardio effects of propofol?
Hypotension
Vasodilation
Compensatory increase in HR
Decrease in myocardial contractility
140
What patient should you be cautious about giving propofol to?
Hypovolemic patients (due to hypotension and vasodilation)
141
What are 2 respiratory affects of propofol?
Severe respiratory depression
Apnea or hypoventilation (dose dependent)
142
Does propofol have analgesia?
No
143
What does propofol cause in cats in the blood?
Heinz bodies
144
What urine outcome of propofol happens that is not a concern?
Green urine
145
How long will alfaxalone last in the container?
28 days
146
Is alfaxalone a controlled drug?
Yes
147
What is the mechanism of alfaxalone?
Binds GABAa cell surface receptors and modulates neuronal chloride ion transport
148
How long does alfaxalone last?
5-20 min
149
How is alfaxalone metabolized?
Liver
150
How is alfaxalone excreted?
Bile and urine
151
What are the cardiovascular side effects of alphaxalone?
Dose dependent!
Hypotension
Vasodilation
152
What are the respiratory side effects of alphaxalone?
Dose dependent respiratory depression
Severe hypoventilation and apnea if a lot given
153
Tell me about alphaxalone in c sections
Alphaxalone saw better puppy vigor after c section than propofol
154
Is there analgesia with alphaxalone
No!
155
What type of steroid is alfaxalone?
Neuroactive (nonhormonal)
156
Etomidate is ______ soluble at acidic pH
water
157
Etomidate is _______ soluble at physiologic pH
lipid
158
Etomidate is classified as a _____
Hypnotic
159
What is the mechanism of action of etomidate?
GABAa selective modulator
160
How is etomidate metabolized?
Liver
161
How is etomidate excreted?
Urine and bile
162
How fast do propofol, alfaxalone, and etomidate cause unconsciousness?
Immediately
163
How is the induction of etomidate?
Rapid but can be rough
(Smooth recovery tho)
164
What are the cardiovascular side effects of etomidate?
Minimal to no effects on blood pressure, cardiac output, or heart rate!
Great for heart patients
165
What are respiratory side effects of etomidate?
Minimal to no respiratory effect!
166
What is an important side effect of etomidate?
Decrease in cortisol, corticosterone, and aldosterone (adrenal suppression)
167
What dog do you NEED to avoid giving etomidate?
Addison dogs!
168
What are 2 other common side effects of etomidate?
Myoclonus (twitching)
Retching during induction
169
What is the original cyclohexylamine and most potent?
Phencyclidine
170
What is the least potent?
Ketamine
171
What is telazol?
Tiletamine + zolazepam
172
How does dissociative anesthesia work?
An interruption from the unconscious to conscious parts of the brain
173
Describe the dissociative state in 4 ways
Cataleptoid state
Opened eyes
dilated pupils
Palpebral reflex
174
What are the 2 carbon atoms in ketamine bottle?
S(+) and R(-)
175
Which carbon is more potent and just better?
S(+)
176
What is the mechanism of action of ketamine?
Non-competative antagonist of NMDA receptor preventing binding of glutamate and glycine. Results in depressed activity
177
Where are NMDA receptors
In nerve cells
178
Ketamine has what affect on bronchials?
Bronchodilation
It is a muscarinic with sympathomimetic action!!
179
Does analgesic outlast anesthetic effect?
Yes!
180
Ketamine wears off faster than its excreted
Duration of action related to redistribution to lean body tissues and fat
181
How is ketamine metabolized?
In liver
182
Norketamine is metabolized in which species?
dogs and horses
183
Norketamine is not metabolized (and just excreted) in which species?
Cat
184
What ways can you administer ketamine?
IV or IM
185
What must be combined with ketamine to give muscle relaxation?
A muscle relaxant (maybe midazolam, propofol)
By itself, it has 0 muscle relaxation
186
What are the 2 cardiovascular effects of ketamine?
Causes an increase in BP, HR, and CO due to the sympathomimetic effect
Eventually it wears off to a myocardial depression
187
What is the respiratory side effect of ketamine?
Mild respiratory depression
188
What does ketamine always need to be used with?
A muscle relaxant
189
What is an additional side effect of ketamine (2 actually)?
-Increased brain and eye pressure
-Increased salivation
190
What type of patient should ketamine not be used on?
Brain tumor patient
191
What is telazol a mixture of?
1:1 mixture of tiletamine and zolazepam
192
In cats, does tiletamine or zolazepam last longer?
Zolazepam
193
In dogs, does tiletamine or zolazepam last longer?
Tiletamine
194
What type of induction is telazol usually associated with?
Rough inductions
195
What species are telazol commonly used in?
Horses, dogs, cats, pigs
196
What is the mixture in large animal that involves telazol?
TKX = Telazol, ketamine, xylazine
197
What cardiovascular side effects does telazol have?
Similar increase of HR, CO, and BP as ketamine
198
What side effect does telazol not have that ketamine does?
Increase in brain and eye pressure
199
What type of breathing pattern does ketamine cause?
Apneustic (large breaths, then short breaths, then large breaths, etc) breathing pattern
200
What happens to excretion of alfaxalone in cats?
Has a potential to accumulate
201
What are the 4 basic components to an anesthesia machine?
Gas source
Vaporizer
Flow meter
Pressure regulator
202
What is the letter for a small tank?
E
203
What is the letter for a large tank?
H
204
When should you replace the oxygen tank?
When it falls below 200psi
205
How do you calculate the volume in an oxygen tank?
Volume = pressure (psi) / 3
206
How many psi are in a full tank?
1900 psi
207
How many liters are in a full tank?
660L
208
When are you in the high pressure system?
In the tank, manometer
209
What transitions gas from high pressure system to intermediate pressure system?
The pressure reducing valve (regulator)
210
What transitions gas from intermediate pressure to low pressure system?
Flow control valve
211
When does the house pipeline come in?
In the intermediate pressure system
212
What is the flow control valve and what system is it in?
It is the knob on the flowmeter.
Knob is in the intermediate system but the flowmeter is in low system
213
What system is the oxygen flush valve in?
Intermediate system!
214
Where do you read the sphere?
In the middle
215
Where do you read the diamond?
At the top
216
How often should a machine be services?
Once a year
217
How does the soda lime work in rebreathing system?
CO2 is an acid and soda lime is a base so when air flows through, CO2 is removed and gas is recycled
218
How do you determine how big your reservoir bag should be?
5 x TV
Or (50-100 mL/kg)
219
How do you know if it is a rebreathing system or not?
If there is a canister -> rebreathing
If no sodalime canister -> Not rebreathing
220
What do you need to ensure on the one way valves?
That they are dry and not warped (especially on CO2 rebreathing)
221
What happens if there is an incompetent one way valve?
Movement of CO2 up the inspiratory limb and then there will be consumption of CO2 on next breath from that limb
222
How can you tell if a one way valve is bad?
Can see both opening at the same time
223
What does new sodalime feel like?
Moist and crumbly
224
What does exhausted sodalime feel like?
Dry and hard
Color is not reliable
225
How should the pop off valve be left?
OPEN!!!
226
When should you use non-rebreathing system?
in smaller patients (<5kg)
227
What is the minimum volume to meet vaporizer fresh gas flow needs in a rebreathing system?
500mL/min
228
What is the fresh gas flow rate of rebreathing system?
20mL/kg/min
229
What is the fresh gas flow rate of non rebreathing system?
200mL/kg/min
230
Where is gas waste vented from?
APL valve
231
What is active scavenging?
Negative pressure is generated by vacuum pump and gases are actively removed from exhausted port
232
What is passive scavenging?
Into charcoal canister and released
233
Veterinarians are at higher risk of pregnancy loss
Make sure ETT cuff is always properly inflated
Only turn vaporizer on after cuff is inflated
Make sure appropriate scavenging is used
Make sure anesthesia machine is checked before each case
After breaking iso, evaluate area, ventilate area, treat as hazardous waste, wash area with water, avoid skin and eyes, collect in plastic bags with respirators and gloves
Small spills can let evaporate, ventilate area, evacuate personnel
234
Which induction drug is least likely to cause apnea?
Etomadine and ketamine
235
Which induction drug does not require hepatic metabolism
Propofol
236
Is propofol 28 labeled for cats?
NO!!!
237
What patient might you be worried about using propofol in?
A puppy with a non developed liver
A portosystemic shunt dog
238
What drug should you avoid in heart diseased patients?
Ketamine!
239
What is physiological pain?
Pain where no or minimal tissue injury occurs (ouch pain - protective warning system)
240
What is pathologic pain?
Pain following tissue injury
241
What is spontaneous pain?
Pathologic pain in absence of noxious stimulus
242
What is allodynia
Pathologic pain in response to normally innocuous stimulus
243
What is hyperalgesia?
Exaggerated pathologic pain in response to a noxious stimuli.
244
Pain may be ______ or ________
Somatic or visceral
245
What are the phases of nociception in order?
Transduction
Transmission
Modulation
Projection
Perception
246
What are the 2 types of fibers peripherally?
A-delta
C fibers
247
Which is responsible for fast pain and which long pain?
A-delta (myelinated) short pain
C fibers (unmyelinated) long pain
248
Where are the nerve bodies for transmission?
In the spinal cord dorsal root ganglia
249
What are the areas of the brain that are responsible for perception of pain?
Periaqueductal grey matter
Reticular activating system
Thalamus
250
What does CNS plasticity do?
Cause hypersensitivity to acute and chronic pain
251
What is sensitizing soup and what does it do?
A bunch of inflammatory cells and nerve growth factors and substance P that increase sensitivity to nociceptors
252
What is wind up also known as?
Temporal summation
253
What is the cellular physiology being temporal summation (wind up)
Unblocking of NMDA-receptors leading to hypersensitivity
254
What is the definition of an animal that is enduring pain?
Suffering
255
What are the 3 types of visceral pain?
Stretch
Hypoxemia
Inflammation
256
What is neuropathic pain
damage of the nervous system leading to hypersensitivity and Spontaneous Activity to non-noxious, non-painful stimuli
257
What are some things in the inflammatory soup?
Prostaglandins (released by COX1 and 2), histamine, serotonin, nerve growth factor, cytokines
258
What are the 3 A's of evaluating pain?
Attitude, appetite, activity
259
What is the downside of relying on HR, BP, and RR for pain?
Will level with chronicity
260
What are the 4 parts of taxonomy of pain?
Location (somatic-deep or superficial /visceral)
Severity
Mechanism (inflammatory, neuropathic, or idiopathic)
Severity
261
What is the visual analogue scale?
Graph with no pain to worst pain
262
What is simple descriptive pain?
Check boxes that define your pain pre and post op as none, mild, moderate, or severe
263
What is the scale for the Colorado Pain Scale?
0-4
264
What is Glasgow Composite Pain Scale? (GCPS)
Pain score from 0-20 from 7 different domains
265
When should you give analgesia?
As preemptive analgesia
266
What do opioids decrease the release of in pain management?
Glutamate
267
What 3 things do opioids provide?
Analgesia, sedation, euphoria
268
What 3 things do alpha 2 agonists provide?
Analgesia, muscle relaxation, sedation
269
Which species are alpha 2 agonists good for?
Equine
270
What part of pain does NMDA antagonists (ketamine) act on?
Treats wind-up pain (central sensitization)
271
How do local anesthetics work?
Block nerve transmission by blocking inflow of Na+ - sodium channel blockers
272
What are the 4 types of local anesthetics?
Lidocaine, ropivacine, bupivacain, mepivicaine
273
What is known as kitty magic?
Dexmedetomidine
Ketamine
Butorphanol
274
What 3 things can NSAIDs do?
Anti inflammatory
Antipyretic (lowers fever)
Analgesic
275
What 4 things are activated during inflammation?
Phopholipase A
COX
LOX
Nuclear factor kappa beta
276
How do NSAIDs act?
Act against COXs
COX-1 is constitutive
COX-2 is constitutive and inducible
Mostly inducible tho
COX-3 is inducible
277
What are the 4 side effect of NSAIDs?
Antithrombic
Gastric defect
Renal damage
Hypersensitivity runs
(chance of hepatopathy in dogs)
278
When should you NOT USE NSAIDS?!
Patient is concurrently on steroids
279
Which NSAID is toxic to animals?
Acetaminophen
280
What NSAID does not inhibit COX? What does it target?
Galliprant
Prostaglandin EP4 receptor
281
What type of local anesthetic is not metabolized in the liver?
Amino esters (procaine)
282
Why do local anesthetics not work well at inflamed tissues?
Venules and capillaries are dilated in inflamed tissues causing increased blood flow to the area which promotes absorption and removal of the local anesthetic
283
What local anesthetic lasts the shortest and the longest?
Lidocaine the shortest
Bupivacaine the longest
284
What local anesthetic takes the longest to start working?
Lidocaine shortest
Bupivacaine longest
285
What can cause a local anesthetic to last longer?
Adding a vasoconstrictor like epinephrine
286
What needs to be considered when the patient is pregnant with local anesthetics?
There is a lot of placenta transfer from mother to fetus
287
What decreases transfer of local anesthetic from mother to fetus?
High protein binding
288
What local anesthetic should be used?
Bupivacaine
Longest protein binding
289
What local anesthetic has the highest risk of toxicity if it goes IV?
Bupivacaine
290
Lidocaine can go IV
Lidocaine causes vasodilation
291
What local anesthetic is used in horses?
Mepivacaina aka carpocaine
292
For local anesthetics, will CNS or cardiovascular toxicity appear first?
CNS!
293
For bupivacaine, will CNS or cardiovascular signs appear first?
Cardio can show first
294
How much higher does dose need to be to cause myocardial toxicity with local anesthetics?
4x
295
How do you treat cardiovascular toxicity of local anesthetic?
Ventilation
Epinephrine
296
How do you treat cardiovascular toxicity of bupivacaine?
CPR
Intralipid bolus**
297
What local anesthetic should you use for an instratesticular block?
Lidocaine
Scrotal approach - cat
Prescrotal approach - dog
298
Where does lidocaine go with the intratesticular block?
Somatic chord
299
Do local anesthetics delay healing or increase risk of infection?
NO!
300
What can you do if the maximum dose is reached on a line block?
Add saline
301
What does the infraorbital block block? lol
Infraorbital nerve and rostral maxillary alveolar nerve
302
Where is the needle inserted in the infraorbital block?
doral to the 3rd premolar
303
What teeth are blocked in infraorbital block?
Premolars forward
304
What needs to be considered when doing infraorbital block on cats or brachycephalic dogs?
Puncturing the orbit
305
what is a different technique that can be used on brachycephalic and cats?
Perpendicular approach
306
What does the maxillary block block?
Maxillary branch of trigeminal
307
What does the maxillary branch innervate?
Nose, upper lip, upper teeth, maxilla
308
What is the approach for maxillary block?
Behind last molar perpendicular
309
What does the inferior alveolar (mandibular) block block?
Mandibular branch of trigeminal
310
What structures are blocked with the inferior alveolar block?
Lower teeth
311
What does the mental block block?
Just the chin...
Not teeth!
312
What is most preferred epidural drug?
Opioid - preservative free morphine
313
What is the tallest spinous process that should be used for locating L7?
L6
314
What are the 3 indications that you are in the right spot when placing the epidural?
1. You feel a pop, meaning you passed through the ligamentum flavum
2. Saline is sucked
3. You feel a change in resistance
315
What if there is CSF or blood in hub?
Too lateral, reposition
316
What are the 3 nerves blocked in a nerve block?
Radial
Median
Ulnar (doral and palmar)
317
What nerves are blocked in the proximal paravertebral nerve block?
L1, L2, L3
318
What nerves are blocked in the distal paravertebral nerve block?
L1, L2, L4
319
For food animal epidural, where do you block between?
Co1 and Co2
320
Where does the spinal cord end in cows, goats, sheep, and pigs?
S1
321
Where does the spinal cord end in horses?
S2
322
Where does the spinal cord end in dogs?
L6-L7
323
Where does the spinal cord end in cats?
L7-S3
324
What is the mechanism of action of inhaled anesthetics?
Inhibiting GABA and glycine receptors and slowing acetylcholine and glutamate receptors
325
What is the solubility represent?
Speed of induction and recovery
326
What does lower solubility represent?
faster induction and recovery
327
What does MAC stand for?
Minimal alveolar concentration
328
What is MAC equal to?
how much should I use
329
How does solubility change with temperature?
4% increase per celsius
330
What happens with hypothermic patients?
Solubility is increased which causes them to take longer to wake up from anesthesia
331
What should you start a patient at?
2 x MAC
332
What level are most patients adequately anesthetized at?
1.2-1.5x MAC
333
What species has a higher MAC?
Cats
334
What are a couple factors that decrease MAC (less anesthetic)
Hypothermia
Pregnancy
Old
335
What is a factor that increases MAC (more anesthetic)?
Hyperthermic
Excited animals (high catecholamines)
336
MAC is not affected by sex, hypertension, or duration of anesthesia
337
What is MAC for most dogs and horses on Iso?
1.3
(sevo = 2.3)
338
What is MAC for most cats on iso>
1.6
339
What pressure produces the anesthesia?
The brain
340
What is most important factor from producing anesthesia?
Blood:gas solubility
341
What happens with high CO2?
Takes longer to induce patient. Excited patients producing a lot of CO2 will take longer to induce
342
How does most inhalant leave the body?
Through breathing it out
343
What are the side effects of inhalants on respiratory and cardio systems?
Respiratory depression
Increase in intracranial pressure
Vasodilation
Decrease in cardiac output due to myocardial contractility
344
Are inhalants nephrotoxic?
NO!
345
Where does central sensitization occur?
In the spinal cord
346
Avoid alpha 2 with heart disease
Ketamine alone has no muscle relaxant
Medazolam is a good muscle relaxant
Ketamine not used in HCM cats???
347
What 3 things need to be monitored under anesthesia?
Depth of anesthesia
Cardiovascular system
Respiratory system
348
How many stages are in the Guedel Classification?
4
349
What is stage 1?
Analgesia and amnesia. Induction to loss of consciousness
350
What is stage 2? Not commonly seen
Delirium and unconsciousness. From loss of consciousness to onset of automatic breathing
351
What is stage 3?
Surgery anesthesia. Automatic respiration to respiratory paralysis
352
What is stage 4?
Respiratory paralysis to death
353
What are the CNS changes in response to depth?
Movement in response to surgery
Ocular reflex
Pedal reflex (flex to move away from pain)
Anal tone
354
What are the muscle relaxation changes associated with anesthesia plane?
Jaw tone
355
What does palpebral reflex tell us?
Too light = blink response
Just right = no blink
Too deep = no blink
356
Where should dog and cat's eyes be under surgical plane?
Ventromedially
357
Where should a horse's eye be in surgical plane?
One rostral, one central
If waking up, maybe nystagmus
358
What happens if the animal is too deep?
Eyes are central with dilated pupils
359
Can you check for surgical planes with jaw tone (too deep, too light, and appropriate depth)
Yes!
360
What does a high HR and BP mean for the plane?
Too light
361
What does a high HR and low BP mean for the plane?
getting deeper
362
What does a low HR and BP mean for the plane?
Deep
363
What are 2 other ways to check cardiovascular system?
Mucous membrane color
Capillary refill time
364
What lead is usually read on ECG?
lead II
365
What does hyperthyroidism due to heart rate under anesthesia?
Increases (tachycardia)
366
What are the 2 stages of Cushings reflex
Stage 1 = tachycardia + hypertension
Stage II = bradycardia + hypertension + abnormal respiration pattern
367
What are 2 devices to monitor BP noninvasive?
Doppler
Oscillometric (cuff)
368
What is hypotension in SA?
below 60
369
What is hypotension in horses?
Below 70
370
Which 3 types of drugs cause hypotension
Ace
Inhalants
Propofol
371
What 3 types of drugs cause hypertension
Ketamine
Alpha 2
Catecholamines
372
What is capnometry?
Continuous measurement of inspired and expired gases of CO2
Non-diverting or diverting (takes a little longer) are available
373
Need to look at screenshot of capnograph on iPad
374
What is phase 1 of capnograph?
Inhalation phase
375
What is phase 2 of capnograph?
CO2 coming from upper airways (breathing out)
376
What i phase 3 of capnograph?
CO2 coming from the alveoli
377
What is phase 4 of capnograph
Beginning of inhalation (breathing in)
378
What is the CO2 measurement that should be considered?
PaCO2
379
What might exhausted sodalime cause?
Hypercarbia
380
What is the minimum PCV?
20%
381
What are some factors that may interfere with pulse oximeter?
Vasoconstriction
Shivering
Pigmentation
382
How long do you have to intubate before desaturation in healthy animals?
3 minutes
383
What is normal tidal volume?
10-15ml/kg
384
During inhalation, blood flows into the thorax due to a decreased intrathoracic pressure (just like air does)
385
What happens to blood flow to chest with assisted ventilation?
Less blood flow due to lack of negative intrathoracic pressure
386
When should ventilation be considered?
When PaCO2 is greater than 60
387
What is after load
Aortic pressure
388
What is a PEEP used for?
Help prevent collapse of the dependent lung
Decrease work of breathing
389
What do all preganglionic neurons secrete?
Acetylcholine
390
parasympatholytics = AntiSLUD
SLUD is salivation urination and defication
391
What is the definition of hypotension in mean and systolic?
Systolic <80
Mean < 60
392
Which machine only monitors systolic BP?
Doppler
393
What is the most common complication in veterinary anesthesia?
Hypotension
394
What 5 meds cause hypotension?
Ace
Propofol
Alphax
Inhalants
Phenoxybenzamine
395
Can severe hypercapnia cause hypotension?
Yes
396
What are the 4 basic causes of hypotension?
Vasodilation
Bradycardia
Decreased inotropy
Hypovolemia
397
Do histamines cause hypotension?
Yes!
398
What drug can you use to treat vasodilation?
Norepinephrine
399
In which patients is hypotension more of a concern?
Renal patients
400
What is definition of hypertension?
Systolic above 180
Mean above 140
401
What drug may cause hypertension?
Alpha 2 agonists (also renal disease)
402
What can hypercapnia cause?
Hypertension
403
What is the most common arrhythmia in patients under anesthesia?
Sinus bradycardia
404
What drugs can cause bradycardia?
Alpha 2 agonist
Opioids
Inhalants
405
How to treat bradycardia?
Atropine (anticholinergic)
406
What drug can cause tachycardia?
Ketamine
Anticholinergics
407
How are temperature signals transmitted? (Same as pain)
A delta and C fibers
Cold through A delta
Warm through C
408
What is the definition of hypothermia?
Below 98
409
What are the 4 mechanisms of heat lost?
Radiation
Conduction
Convection
Evaporation
410
What is radiation?
Heat loss from skin
411
What is conduction?
Heat to surrounding, like a cold surface
412
What is convection?
Air currents
413
What is evaporation?
In feces and urine
414
What are the 2 most common ways to lose heat?
Convection
Radiation
415
What is the definition of hyperthermia?
Above 102.2
416
What is the complication with hyperthermia?
Organ failure
417
What is the definition of hypoventilation (hypercapnia)
PaCO2 greater than 60
Et greater than 55
418
What is weird about hypercapnea?
It can lead to both hypertension and hypotension
419
How to treat hypoventilation?
Decrease anesthetic depth
Increase O2 flow rate
420
What is definition of hyperpnea?
Abnormal increase in rate and depth
421
What is definition of tachypnea?
Rapid, shallow respiration
422
What does hypocapnia cause?
respiratory alkalosis
423
What does hypoxemia cause?
Lactic acidosis
Causes blue mm, increase in HR, increase in RR
424
What are causes of hypoxemia?
Hypoventilation
R-L shunt
V/Q mismatch
425
What is something easy you can do to reduce hypoxemia?
Pre-oxygenation
426
Should low Sp02 be treated by increasing O2?
No, already breathing 100% O2
427
Need to be within 4cm for flu-by oxygen to have nay affect
428
Getting the tongue wet does not increase accuracy of pulse oximetry
429
44% of dogs die within 3 hours of anesthesia and 62% of cats
430
What are the 3 main reason for small animals to have a rough recovery?
Emergence delirium (wake up and freak out)
Opioid-induced dysphoria
Pain
431
What is the affect on preload when the patient is vasodilated?
Blood is pooling in areas of the body so this decreases preload
432
What is the dose of xylazine compared to that of horse?
1/10
433
What should you do in a patient if their PaO2 is low?
Give a bronchodilator
434
What should you do in a patient if their PaCO2 is high?
Ventilate
435
Does propofol cause vasodilation or vasoconstriction?
Vasodilation
436
Which of the induction drugs dont metabolize fully in the liver?
Just propofol
437
What is apeneic?
Involuntary pause in breathing
438
What can a 2nd degree AV block be caused by?
When dex is given
439
What should be considered when irregular rhythms are seen?
Anticolanergic
440
What should not be done in renal disease patients to treat hypotension?
Be given a fluid bolus quickly
441
True or false: Most animals do not need fluids under anesthesia
True
442
What are the 2 common types of drip sets?
10 drops/mL
60 drops/mL
443
What crystalloid fluid does not have Ca: LRS, plasmalyte, saline
Plasmalyte
444
What are common crystalloid fluid rate for dogs and cats?
Dogs: 5mL/kg/hour
Cats: 3mL/kg/hour
445
What does OSU require before every surgery at <5 within 24 hr?
PCV/TP
446
What does OSU require for patients >5 within 30 days and then within 24 hours?
CBC/Chem
PCV/TP
447
How do you calculate the size of the reservoir bag?
10 x kg x 5
448
What is the maintenance for a dog?
10-40 mL/kg/min
449
How do you calculate the amount of liters left in a tank based off of the psi?
psi/3 = L
450
Calculate maintenance for a 50kg dog?
~20 x 50kg = 1000mL = 1L
451
If the tank has 466L and the maintenance is 1L/min, how many minutes doe the tank have left?
466-200L (always leave 200 left in it) = 266 minutes
452
What is the maintenance rate for a non-rebreathing tube?
100-400. so use 200 (10x more than rebreathing)
453
How long should adult cattle be fasted?
18-24 hours
454
Why should you not starve a ruminant more than 24 hours?
Development of ketosis
455
What are the top 2 worries for ruminant with anesthesia?
Bloat
Aspiration
456
How much saliva do cattle produce a day?
50-150L
457
Why are anticholinergics not indicated to reduce saliva in ruminants?
It reduces only the watery part of saliva and leaves the viscous part which is worse
458
Where should the head be during sedation of cows?
Head down
Leave in sternal when possible
459
Why should you never tie the endotracheal tube over the nose in ruminants?
It will stop breathing
460
Head elevated but nose down
461
What are 3 reasons endotracheal tube placement in ruminants is hard?
Small opening of the mouth
Lingual torus
Narrow and long oral cavity
462
What is the most sensitive species to xyalzine?
Goats
463
Where can you go to find recommendations for drugs off label?
FARAD
464
What is a unique concern in some breeds of pigs for anesthesia?
Malignant hyperthermia
465
What triggers malignant hyperthermia?
Inhalants and stress
466
What is common in pigs during endotracheal intubation?
Laryngospasm (use lidocaine)
467
What is sedation commonly used in pigs?
TKX
Telazol
Ketamine
Xylazine
468
What should be watched in all species in neonates?
Hypoglycemia!
469
What are 4 things that a make anesthesia of horses difficult?
Flight animals
Colic potential
Obligate nasal breathers
Depth of anesthesia may change quickly
470
What is the best drug to use for equine sedation?
Alpha 2
471
What are the 3 criteria for properly sedated horses?
Reluctant to move
Not interested in surroundings
Head down
472
What is important to never to with horse sedation?
NEVER induce anesthesia in a horse that is not adequately sedate
473
How are induction drugs given, different from other animals?
Rapidly
Horses get nervous and try to run around if not
474
How do you put a horse back to the surgical depth if it begins to wake up?
Injectable needed on hand
Inhalation is too slow
475
How can you prolong anesthesia in the field for horses (what drug can you use on a drip)?
Guaifenesin, Ketamine, Xylazine back
476
What do you need to do post-recovery for horses?
Muzzle for 1-3 hours to prevent esophageal obstruction
477
What drugs are collies, herding breeds sensitive to and what is the mutation?
Ace and butorphinol
MDR1
478
Do overweight patients need more or less dosage?
LESS!
479
**What are the 4 parts of BOAS?
Elongated soft palate
Stenotic nares
Hypoplastic trachea
Everted saccules
480
What is the equation for mean arterial pressure?
CO x SVR
481
What are the 3 things that depend on stroke volume?
Preload, after load, contractility
482
What does low after load mean
high after load?
Low = easier to pump blood forward
High = harder to pump blood forward
483
What may cause a high after load?
Vasoconstriction
484
What type of dog is most likely to get mitral valve disease?
Old small breed dogs
485
What type of dog is most likely to get DCM?
Large breed dogs
486
What are cardioprotective sedatives and analgesics?
Benzos and opioids
487
What induction drug is bad for dogs with Addison's?
Etomidate
488
How should you premed a HCM cat?
Low dose dex or midazolam
489
How many minutes should you pre oxygenate?
3 min
490
What do you fill when you pre oxygenate?
FRC
491
What does FRC stand for?
Functional residual capacity
492
What 2 things make up the FRC?
Expiratory reserve volume
Residual volume
493
What happens if you have low albumin in a patient?
Low albumin means less proteins for the drug to bind to and thus more free proteins to activate causing higher affect
494
What do you reverse a benzodiazepines with?
Flumazenil
495
What should not be used in patients with renal disease?
Vasodilators
May decrease renal blood flow
496
Does vomiting increase brain pressure?
Yes, be careful during intubation
497
What are the 3 contents of the skull?
Brain matter
CSF
Blood
498
What is the Monro-Kellie Doctrine
If one of the 3 things in the brain increase, something else must decrease
499
What table position should nervous system patients be in?
Reverse trendelenburg position
500
