anesthesia exam 1 Flashcards
(387 cards)
1
Q
a loss of sensitivity to pain
A
analgesia
2
Q
is the neural process of encoding noxious
stimuli and does not require consciousness
A
nociception
3
Q
is a state of behavioral change, wherein anxiety is relieved and the patient is relaxed, although aware of its surroundings
A
tranquilization
4
Q
is a state characterized by CNS depression accompanied by drowsiness. The patient is likely unaware of its surroundings
A
sedation
5
Q
refers to a loss of sensation in a circumscribed body area
A
local anesthesia
6
Q
is a loss of sensation in a larger, though limited, body area
A
regional anesthesia
7
Q
is a drug induced state of deep sleep from which a patient cannot be easily aroused. It may or may not be accompanied by antinociception
A
narcosis
8
Q
is a drug-induced unconsciousness characterized by controlled, reversibledepression of the CNS and perception. In this state, the patient is not arousable by noxious stimulation. Sensory, motor, and autonomic reflex functions are attenuated to varying degrees.
A
general anesthesia
9
Q
is induced by drugs that dissociate the thalamocortical and limbic systems.
A
dissociative anesthesia
10
Q
is the stage/plane of general anesthesia that provides unconsciousness, muscle relaxation and analgesia sufficient for painless surgery
A
surgical anesthesia
11
Q
is induced by a multiple drug approach. Drugs are targeted to attenuate individual components of the anesthetic state; unconsciousness, analgesia, muscle relaxation
A
balanced anesthesia
12
Q
minimum acceptable percent oxygen for people and small animals in anesthesia
A
30-35% O2 (FiO2=0.30-0.35)
13
Q
What is the metabolic requirement for oxygen?
A
5-10 mL/kg/min
14
Q
color codes for cylinders in the US:
oxygen?
nitrous oxide?
medical air?
A
Oxygen = green Nitrous oxide (N2O) = blue Medical air = yellow
15
Q
cylinder pressure units
A
Psi
16
Q
breathing system pressure units
A
cmH2O
17
Q
Used to measure cylinder pressures, pipeline pressures, anesthetic machine working pressures, and pressure within breathing system
A
pressure gauges
18
Q
T/F
a breathing system is considered a high pressure system
A
FALSE – low pressure
similar to patients lungs pressure
19
Q
E cylinder capacity
A
Capacity = 660 L
20
Q
H cylinder capacity
A
Capacity = 6600 L
21
Q
E and H cylinders are both filled to what pressure
A
pressure of 2200 psi
22
Q
T/F
N2O exists in both a gaseous and liquid form in the tank
A
TRUE
gauge only tells gas though – weigh tank to know what is left in it
23
Q
Diameter index safety system
A
Non-interchangeable gas-specific threaded connection system
24
Q
Pin index safety system
A
Gas-specific pin patterns that only allow connections between the appropriate cylinder yokes and E tanks
25
also called the pressure reducing valve
Regulator
26
T/F
| the regulator prevents pressure fluctuations as the tank empties
TRUE
27
Decreases tank pressure to a safe working pressure which is supplied to the flowmeter
The Regulator (approx 50 psi)
28
Controls rate of gas flow through the vaporizer
Flowmeter
L/min
29
Gas enters flowmeter at bottom at ___ psi and exits at top at ___ psi
50
15
30
T/F
| flowmeter is gas specific
TRUE
31
if there are multiple flowmeters where should the oxygen one be placed
furthest right -- downstream of the others
32
Delivers O2 from the intermediate pressure area of the machine (50 psi)
quick flush
33
T/F
| the quick flush oxygen contains the anesthetic drug in it
FALSE -- BYPASSES THE VAPORIZOR
34
what rate does the quick flush valve deliver oxygen to the patient
35-75 L/min
35
T/F
| Patient should be disconnected from the circuit temporarily before the O2 flush valve is utilized
TRUE TRUE TRUE
36
T/F
| pneumothorax is a possible complication of using the quick flush valve
TRUE
37
```
Deliver selected % of anesthetic vapor to
the fresh (common) gas outlet
```
Anesthetic vaporizers
unit: volume percent
38
Gaseous state of substance that is liquid at ambient temp and pressure
vapor
39
T/F
| Halothane, Isoflurane, Sevoflurane, and Desflurane are all gases
FALSE -- they are vapors
40
exists in gaseous state at ambient T
| and P
Gas
N2O, Xenon
41
Pressure exerted by vapor molecules when liquid and vapor phases are in equilibrium
vapor pressure
42
T/F
| vapor pressure decreases as temperature increases
FALSE - increases with temperature
43
T/F
| vapor pressure is inversely related to boiling point
TRUE
44
T/F
| All modern vaporizers are out-of- circuit (VOC)
TRUE
*Anesthetic % is known = precision vaporizer
45
which is the only vapor needs an electric vaporizor because its boiling point is close to room temp
Desflurane
46
Describes amount of an anesthetic in the blood vs. alveolar gas at equal partial pressure
Blood-gas partition coefficient
47
T/F
| halothane is most soluble and desflurane is least
TRUE
48
More anesthetic dissolved in blood at
| equal partial pressure (less in alveoli) will give a high or low Blood-gas PC
HIGH
49
which is clinically more useful a low or high blood gas PC
LOW -- Shorter time required to attain a partial pressure in the brain and Short induction and recovery
50
parts of the preanesthetic exam
```
Signalment
History
Physical examination
Laboratory examinations
Advanced diagnostics
```
51
breed specific condition for quarter horses
Hyperkalemic Periodic Paralysis (HYPP)
52
breed specific condition for pugs
Brachycephalic Syndr.
53
breed specific condition for rabbits
Has atropine estherase
54
breed specific condition for Miniature Schnauzers
sick sinus syndrome
55
breed specific condition for doberman
Von Willebrand's dz; DCM
56
normal CRT
1-2 seconds
57
what can a CRT <1 second indicate
may indicate hyperdynamic state and vasodilation (also bight red mm); associated with sepsis, distributive shock, hyperthermia etc.
58
what can a CRT >2 seconds indicate
may indicate decreased peripheral perfusion; associated with shock and dehydration
59
pink and moist mucus membrane
normal
60
pale mucus membrane
anemia, vasoconstriction, hypovolemia
61
brick red mucus membrane
hyperdynamic status (e.g. sepsis)
62
petechial bleeding in mucus membrane
thrombocytopenia, thrombocytopathy
63
cyanotic mucus membrane
hypoxemia
64
Who is the ASA ?
American Society of Anesthesiologists
65
physical status classification: ASA - I
Healthy animal, no systemic disease
66
ASA ___ patients have no functional limitations
1-2
67
what ASA level is a healthy pregnancy
2
68
What ASA is Systemic diseases that are well controlled e.g. diabetes mellitus receiving insulin
2
69
what ASA is mild anemia or fever
2
70
T/F
| ASA III patients have functional limitations
TRUE
71
ASA III includes ...
Poorly controlled systemic diseases
Morbid obesity
Heart disease of moderate degree
Some colic horses
72
ASA ___ have life threatening functional limitations
IV
73
```
These are examples of what ASA level???
CHF
GDV
shock
actively hemorrhaging splenic tumor
```
IV
74
what ASA: Moribund patient that is not expected to survive 24 hours with or without surgery
V
75
ASA V
End stage of shock
Multiple organ/system dysfunction
Massive trauma
76
open lower esophageal sphincter, gastric content enters the esophagus
reflux -- normally invisible/silent
77
passive discharge of gastric content from the mouth during anesthesia
regurgitation
78
preanesthetic fasting for healthy dogs and cats
8-12hours
79
preanesthetic fasting for ferrets
4 hours max
CAUTION INSULINOMA
80
preanesthetic fasting for guinea pigs?????
6-8 hours
81
preanesthetic fasting for horses, pigs, ruminants
12-24 hours
82
why do rabbits and rats not need preanesthetic fasting
they dont vomit
83
T/F
| birds and suckling babies should not be fasted
TRUE
84
____ times more anesthetic is needed to inhibit movement then to inhibit consciousness
3
85
Gives information about cortical but not subcortical activities
EEG
Correlates with anesthetic depth but does not predict arousal in response to noxious stimulus
86
Stage 1 of anesthesia
Voluntary movement
| From drug administration to loss of consciousness
87
what stage of anesthesia:
Excitement and violent struggle may occur
Epinephrine release, tachycardia, pupillary
dilation
Irregular breathing, breath hold, coughing
Salivation, urination, defecation
Ataxia, recumbency
1
88
stage 2 anesthesia
From loss of consciousness until the onset of regular breathing
involuntary movement
89
what stage of anesthesia??
State of delirium
Struggling and exaggerated reaction to stimuli
Epinephrine release, tachycardia, pupillary dilation
Strong palpebral and eyelash reflexes
Irregular breathing, breath holding, laryngeal spasm
Vomiting, regurgitation, salivation
Strong jaw tone, intubation is not possible or difficult
2
90
what stage is general anesthesia
3
91
stage 3 anesthesia
From the onset of regular breathing until the cessation of effective breathing
92
plane 1 of stage 3 anesthesia
Light anesthesia
Nystagmus, lacrimation
Weakening palpebral and corneal reflexes
No swallowing reflex
Pupils constricted
No involuntary movement
Simple procedures/examinations may be possible
93
stage 3 - plane 2 anesthesia
```
Medium plane of anesthesia
Progressive intercostal paralysis
Stable respiration and pulse
Loss of laryngeal reflexes
Weak palpebral strong corneal reflexes
Adequate muscle relaxation for most surgical procedures
```
94
stage 3 plane 3 anesthesia
```
Deep anesthesia
Diaphragmatic (abdominal) breathing
Pupils dilate, eyes central
No palpebral/corneal reflexes
Some patients may have to be maintained at this stage but ideally should decrease to plane 2
```
95
stage 4 anesthesia
overdose
Respiratory failure
Cardiac arrest
Death from overdose
96
T/F
| ketamine suppresses brain activity
FALSE
97
what type of anesthetic is ketamine
dissociative
98
what can ketamine cause at moderate anesthetic depth
nystagmus, blinking, central eye position and dilated pupils
99
rotated eyes likely indicate what stage
Stage 3 Plane 2
100
T/F
| Central eye + dilated pupils may indicate both too light or too deep anesthesia
TRUE -- they need to be distinguished
101
nystagmus or spontaneous blinking most likely indicates ...
too light
exception is horses -- can have with adequate anesthesia
102
T/F
| Absolute HR does NOT aid determining anesthetic depth
TRUE
103
common causes of increased HR
o Surgical stimulus (nociception)
o Life threatening stress (e.g. hypoxemia)
o Anemia, hypovolemia, shock, hyperthermia
104
common causes of decreased HR
```
o Drugs (e.g. opioids, α2 agonists)
o Hypothermia
```
105
how often should ECG be monitored during operation
every 5 minutes
106
T/F
| blood pressure monitoring is recommended for all patients
TRUE
107
common methods for monitoring circulation
```
CRT
pulse
ECG
heart beat ausc
blood pressure
```
108
Subjective measure of adequacy of CO
palpation of pulse
109
T/F
| palpating the pulse is the same as reading blood pressure
FALSE
110
what arteries are good for pulse in small animals
```
Lingual
Labial
Auricular
Digital
Femoral
Dorsal pedal / Metatarsal
Coccygeal
```
111
pulse palpation locations for large animal
Auricular
Transverse facial
Facial
112
T/F
| ECG readings indicate that the heart is contracting
FALSE
113
what are clinical uses of ECG
-Determine heart rate and rhythm
-Aid diagnosis and treatment of electrolyte
disturbances (principally hyperkalemia)
- Aid diagnosis of chamber enlargement
- May provide clues about myocardial oxygenation and perfusion abnormalities and location of certain cardiac diseases
114
P wave
atrial depolarization
115
QRS complex
ventricular depolarization
116
T wave
ventricular repolarization
117
T/F
| small animals have type B cardiac innervation
false -- type A
118
type of cardiac innervation with flow from base to apex
Type A
119
type of cardiac innervation with flow from apex to base
Type B
120
type of cardiac innervation where Purkinje fibers excite the endocardium and excitation spreads via muscle fibers
Type A
121
type of cardiac innervation where Purkinje fibers deeply - penetrate the myocardium
and most of the muscle fibers
are excited simultaneously,
therefore, most vectors cancel each other
B
122
a type A heart will have a ____ R wave
positive
123
a type B heart will have a _____ S wave
negative
124
horses, ruminants, and pigs have what type of cardiac innervation heart
type B
125
In healthy small animals the lead-____ is yielding the tallest R wave, therefore preferred
lead 2
126
what lead is preferred in large animals
lead 1
127
T/F
| always use alcohol when connecting the electrodes in ECG
false -- saline or gel
128
normal HR and BP likely indicate adequate ___
cardiac output
129
what is the best way to determine the HR
count yourself with a watch
| ECG and pulse oximeter also work
130
common types of arrhythmias under anesthesia
Sinus bradycardia and tachycardia
and
AV blocks (1st and 2nd degree)
131
what is the first line of Tx for ventricular arrhythmias
lidocaine IV
132
highest point of the BP curve; represents afterload for the left ventricle
systolic pressure
133
average BP over a full cycle; determinant of tissue perfusion
mean pressure
134
lowest point of the BP curve; determinant of myocardial perfusion
diastolic
135
During hypotension certain organs such as what may become under perfused and sustain hypoxic damage??
brain
kidney
muscles
136
determinant of CO and myocardial work load; provides information about the function of the vegetative nervous system and pain
Heart rate
137
provides information about inotropy, CO and the effect of arrhythmias
pressure waveform
138
what do blood pressure changes with respiration indicate
hypovolemia
139
stroke volume depends on what 3 things
preload, systemic vascular resistance and contractility
140
preload depends on _____
circulating volume
141
Tx for low HR
atropine
142
Tx for low circulating volume
give bolus fluids
143
Tx for low contractility
decrease ISO, give inotropes
144
Tx for low SVR
decrease ISO, give vasoconstrictors
145
3 treatments for hypotension
1. Decrease anesthetic administration
2. Give fluid bolus
3. Give drugs (inotropes or vasoconstrictors)
146
what drugs can be given to treat hypotension
a) Dobutamine, dopamine, ephedrine
| b) Phenylephrine, norepinephrine, vasopressin
147
IBP stands for
invasive blood pressure
148
IBP should be used in horses when anesthetized longer than ____ min
45
149
IBP artery for dog
dorsal pedal, metatarsal
150
IBP artery for cat
dorsal pedal, coccygeal,
151
IBP artery for horse
facial and transverse facial
152
IBP artery for cattle
auricular
153
IBP artery for sheep and goats
median
154
The cuff’s width should be about ___% of the circumference of the limb
40%
155
cuff should be placed at the level of ___
the base of the heart
156
small animal cuff placements
distal radius, distal tibia, metatarsus
157
large animal cuff placements
metacarpus, tail
158
advantages of oscillometry
Provides systolic, mean, diastolic BP
159
T/F
| the doppler is an excellent pulse monitor
true
160
if you can only chose a single anesthesia monitor what should you chose
DOPPLER
161
The process of oxygenating of arterial blood
oxygenation
162
oxygenation is measured by
pulse oximeter or blood-gas
163
what percent of O2 in the blood is bound to Hb
98%
164
O2 pressure in the arterial blood
PaO2
165
O2 saturation of arterial blood measured by a blood gas machine
SaO2
166
O2 saturation of arterial blood measured by a pulse oximeter
SpO2
167
Reduction of oxygenation of art. blood
hypoxemia
168
accepted values that define hypoxemia for PaO2 and SaO2
PaO2 < 60mmHg
| SaO2 <90%
169
Non-invasive method for assessing percent of arterial Hb that is saturated with oxygen
pulse oximetry
170
T/F
| SpO2 >90% is ok
FALSE -- common misconception, needs to be interpreted with FiO2
SpO2 = 90% indicates a problem if FiO2=1
171
when to use a pulse ox
1. Patient is breathing air
2. There is V/Q mismatch
3. There is a respiratory disease
172
what is normal PaCO2
Normal PaCO2 ≈ 35 - 45 mmHg
173
The process involved in the movement of air (gas) in and out of the alveoli
ventilation
174
PaCO2 > 45 mmHg
hypercapnia, or hypoventilation
175
PaCO2 is 35-45 mmHg
normocapnia, or normoventilation
176
PaCO2 is < 35 mmHg
hypocapnia, or hyperventialtion
177
continuously displays ET CO2 vs.
| time on a graph
capnograph
178
only measures the ET CO2
capnometer
179
anticholinergics MOA
inhibit the PSNS
| antagonists on muscarinic acetylcholine receptors
180
atropine is ___ soluble
lipid
181
T/F
| Atropine crosses the BBB and placenta
TRUE
182
how to dose atropine
0.01 – 0.04 mg/kg iv
183
what ways can atropine be administered to absorb well
IM
SC
PO
184
glycopyrrolate is ______ soluble
water
185
which has a faster onset of action:
| atropine or glycopyrrolate
atropine
186
T/F
| glycopyrrolate crosses the BBB and placenta
FALSE
187
indications for using anticholinergics (atropine and glycopyrrolate)
to increase the HR
| to decrease salivation and bronchial secretions
188
what are contraindications for using anticholinergics (atropine and glycopyrrolate)
tachycardia
hyperthyroidism
most heart diseases
narrow angle glaucoma
189
anticholinergics easily effect ___ node
SA -- lots of P waves (atrial depolarization)
190
result of atropine with medetomidine
vasoconstriction, tachycardia, hypertension
dont combine these drugs
191
T/F
| Routine co-administration of an α2 agonist and an anticholinergic is contraindicated
TRUEEE
192
why should glycopyrrolate be used over atropine in rabbits
most rabbits have high levels of atropinase enzyme, so atropine is quickly broken down and not effective
193
benzodiazepines are ______ receptor agonists
GABA
194
T/F
| benzodiazepines cause analgesia
FALSE
195
what are the effects of benzodiazepines
Sedative, anticonvulsant, muscle relaxant effects
196
______ is the main inhibitory neurotransmitter in the CNS
GABA
**Benzodiazepines allosterically activate this receptor (no maximal effect)
197
GABA antagonists
Flumazenil
Sarmazenil
**benzodiazepine antagonist
198
what species do benzodiazepines have the best sedative effects in
ruminants, camelids,
| pigs, birds, and ferrets
199
when using benzodiazepines in premedication what should you combine with
1. opioids
2. alpha 2 agonists
3. both
200
what do you combine benzodiazepines with during induction
Dissociative anesthetics (ketamine) Barbiturates or propofol
201
T/F
| benzodiazepines can be used for treatment of seizures in status epilepticus
TRUE
202
Diazepam is ______ soluble
lipid
203
oral diazepam in cats?
no -- liver damage
204
how should diazepam be given
slowly IV
there is poor absorption and pain when given IM
205
where is diazepam metabolized and what is the duration of action
in the liver -- duration of action is 1-4 hours
206
what is diazepam formulated in that is different from midazolam
propylene glycol or lipid emulsion
207
which has better chemical compatibility:
| diazepam vs midazolam
MIDAZOLAM
208
midazolam is ______ soluble
water
209
which is more potent:
| diazepam vs midazolam
midazolam
210
which is shorter acting:
| diazepam vs midazolam
midazolam
211
which has active metabolites:
| diazepam vs midazolam
diazepam
212
how can midazolam be given
IM, IV or via mucus membranes
213
strongest available sedatives
alpha 2 agonists
214
effects of α2 receptors on the presynaptic membrane
sedation and analgesia
215
T/F
| Medetomidine decreases NE and EPI blood levels
TRUE -- reduces stress response
216
α2 receptors on the postsynaptic membrane are located where
wall of arteries and veins
217
activation of α2 receptors on the postsynaptic membrane causes _____
vasoconstriction = most concerning side effect of alpha 2 agonists
218
α2 receptors on adipocytes
inhibit lipolysis
219
α2 receptors on pancreas beta cells
inhibition of insulin release, therefore causes hyperglycemia
220
what species has weak sedative effects from α2 agonists
pigs
221
CV effects of α2 agonists
strong vasoconstriction -- high SVR and BP
reflex bradycardia --low CO and tissue perfusion
222
α2 agonists: respiratory effects
mild resp depression
upper airway resistance increases
V/Q mismatch
223
why is xylazine contraindicated in sheep
Bronchoconstriction, V/Q mismatch, lung
| edema and hypoxemia in ruminants
224
xylazine causes vomiting in this species
cats
225
xylazine may cause uterine contractions and abortion in this species
cattle
226
α2 agonists: indications
Sedation of aggressive animals
Sedation in the ICU
Sedation to manage post operative airway obstruction (e.g. after brachycephalic surgery)
227
drug category:
Xylazine
Dexmedetomidine
Medetomidine
alpha 2 agonist
228
drug category:
Atipamezole
Yohimbine
Tolazoline
alpha 2 antagonist
229
Intra-arterial injection of this alpha 2 agonist may cause excitement (seizure) in horses and should be avoided
xylazine
230
duration of action of xylazine
20-40 minutes
231
Medetomidine is a 50:50 racemic mixture of what
Dexmedetomidine is the active optical isomer
Levomedetomidine is inactive isomer
232
The most specific drug for α2 receptors
Dexmedetomidine
233
T/F
| Detomidine is used in small animals
false - large
234
Detomidine dosing
0.01-0.02 mg/kg
given IM, IV, sublingual
235
duration of action of Detomidine
90-120 minutes
236
Romifidine is used in what species
horses
237
Romifidine dosing and route
0.07-0.12 mg/kg
IM or IV
238
Romifidine duration of action
45-90 minutes
239
acepromazine is a phenothiazine
true
240
what receptors does acepromazine antagonize
o Dopamine
o Serotonin
o α1
o Histamine
241
Acepromazine duration
long acting = 4-8 hours
could last 48 if liver function is decreased
242
T/F
| Phenothiazines have antiemetic effects
true
243
T/F
| phenothiazines have analgesic effects
FALSE
244
T/F
| phenothiazines have stronger sedative effects compared to α2 agonists
FALSE -- weaker
245
Cardiovascular effects of phenothiazines
vasodilation and hypotension
death of hypovolemic patients
246
cause penile prolapse in horses
Phenothiazines
247
T/F
| Phenothiazines can inhibit platelet function
true
248
Phenothiazines indications
mild sedation for premed or post op
tx opioid dysphoria
Prevention of emesis caused by morphine
Sedation for dogs with laryngeal paralysis
249
contraindications of phenothiazines
Hypovolemia, hemodynamic instability
VWD patients bc platelet issues
boxers sensitive - bradycardia
stallions bc penile prolapse
250
droperidol and azaperone
Butyrophenones
have sedative effects
less platelet effects
more likely to cause behavioral side effects
251
which is more likely to cause behavioral side effects:
| Butyrophenones vs phenothiazines
Butyrophenones -- droperidol and azaperone
252
best choice of tx for acute pain
opioids
253
Exogenous substances that bind to opioid receptors and activate them
opioids
254
Strongest available systemic analgesics
opioids
255
opioid receptor with the strongest analgesia and respiratory depression
u
256
this mixed agonist antagonist opioid is an antagonist on mu and agonist on kappa receptors
butorphanol
257
Schedule I opioids
no medical use -- heroin
258
Schedule II opioids
drugs with a high potential for abuse,
| e.g. most full mu agonists (morphine)
259
schedule III opioids
drugs with a moderate to low potential for abuse (e.g. buprenorphine)
260
Schedule IV opioids
drugs with low potential for abuse (e.g. butorphanol, tramadol)
261
potency vs efficacy
potency tells dose
| efficacy tells strength of effect
262
which is more potent:
| fentanyl vs hydromorphone
fentanyl
aka a lower dose will give the same effect as hydromorphone
263
which will have a higher efficacy:
| full agonist or partial agonist
full -- gives highest possible effect
264
activate receptors and trigger full tissue response
full agonist
265
activate receptors but do not trigger full tissue response even at high doses
partial agonist
266
bind to receptors but do not trigger detectable tissue response
antagonist
267
T/F
| opioids decrease the MAC of inhalants
true
268
T/F
| opioids are better for chronic pain over acute
FALSE -- best for acute but can do both still
269
Which opioids will cause vomiting:
| water soluble or lipid soluble
water soluble -- enter brain more slowly and cause the vomiting -- stimulate CTRZ first and trigger vomit before brain can be shut it off
lipid soluble enter the brain fast so there is not vomiting bc once opioids enter the brain the vomit center is inhibited
270
T/F
| there are no direct cardiovascular effects of opioids and so they are suitable for more risk patients
true
271
T/F
| Opioids have antitussive effect
TRUE - may be used to inhibit coughing
272
premed with opioids alone or in combo with ....
o Benzodiazepines
o Benzodiazepines and ketamine (cats, small dogs)
o Acepromazine
o α2 agonists (xylazine, dexmedetomidine)
273
T/F
| morphine is lipid soluble
FALSE - water soluble
274
what are the onset and duration of morphine
Slow onset (30-45 min) long duration (4-6 hours)
275
duration of epidural analgesia using morphine
epidural analgesia is 12-24 hours
276
what can morphine cause to be released after high IV doses
histamine
277
T/F
| morphine is matabolized in the liver to an inactive metabolite
false -- active
278
Hydromorphone, oxymorphone duration
4 hours
279
T/F
| Hydromorphone and oxymorphone are full u agonists
TRUE
280
Similar properties to hydromorphone
| But also acts as NMDA antagonist
methadone
281
bolus dose for small animals with fentanyl
2-5 μg/kg IV
282
fentanyl is a _____ u agonist
full
283
onset and duration of fentanyl
```
show onset
fest duration (15-20minutes)
```
284
Remifentanil has a similar potency to what full u agonist
fentanyl
285
duration of Remifentanil
5 minutes
286
T/F
| fentanyl does not accumulate and so it is ideal for CRI
FALSE -- this is Remifentanil
287
Remifentanil boluses may cause sudden _______
bradycardia
288
Antagonist on μ and agonist on κ receptors
butorphanol
289
this opioid may worsen pain sensation in cases of strong pain
butorphanol
290
T/F
| butorphanol is a weak and short acting analgesic
TRUE
291
Partial μ agonist that has a stronger analgesic effect than butorphanol
Buprenorphine
292
Often given to cats because may cause less excitation than full μ agonists
Buprenorphine
293
onset and duration for buprenorphine
Relatively long acting: 6-8 hours
| Onset is slow (20-40 min iv)
294
T/F
| Tramadol can be given PO
TRUE
295
T/F
| Tramadol has strong analgesic effects
FALSE -- weak
296
Tramadol mechanism of action
inhibits NE and serotonin reuptake
Metabolizes in the liver and its metabolite is μ opioid agonist
297
list 2 opioid antagonists
Naloxone
| Naltrexone
298
what doe naloxone reverse
analgesia and respiratory depression
299
naloxone duration
30 min duration
300
used to antagonize wild animals after long acting opioids
naltrexone
301
naltrexone duration
10 hours
302
centrally acting muscle relaxant
Guaifenesin
303
Causes skeletal muscle relaxation with little
| effect on respiratory muscles
Guaifenesin
304
greater than what percent of Guaifenesin can cause thrombophlebitis
>10%
305
what is the most common concentration of GG mixed with dextrose used
5% GG with dextrose
306
onset and duration for Guaifenesin
Onset of effect: ~2 min, duration 10-20 min
307
T/F
| with Guaifenesin there is no analgesia or unconsciousness
true
308
T/F
| Guaifenesin and ketamine are part of triple dip
true
309
what are the top 3 priorities when inducing anesthesia
1. Rapidlysecureairwaysandgiveoxygen
2. Maintaincardiovascularfunction
3. Induce/maintainanesthesia
310
Most common inj. anesthetic in small animals
propofol
311
.onset and duration of propofol
fast short
312
T/F
| propofol accumulates in tissues
FALSE -- does not .. ideal for TIVA
313
T/F
| propofol has analgesic effects
false
314
why must propofol be injected slowly
due to the CV effects -- could have hypotension and vasodilation
315
what does propofol do to respiration
depression -- apnea possible
| does not inhibit laryngeal movement
316
CNS effects of propofol
Decreases cerebral metabolic O2 consumption
Cause cerebral vasoconstriction
Reduces intracerebral blood volume and pressure
Has antiepileptic effect and may be used to terminate status epilepticus
317
what drugs will increase the intracranial pressure`
ketamine/dissociative anesthetics
| inhalants
318
what are some concerns with giving propofol to cats
recovery is slower
heinz bodys and hemolysis
pain during injection
319
drug of choice for C sections
propofol
320
how can alfaxalone be given
IV IM
| good for CRI - no accumulation
321
neurosteroid anesthetic with minimal CV effects
alfaxalone
322
T/F
| the new formula for alfaxalone causes histamine release
false
323
drug with almost no CV effects, has transient adrenal suppression, and no analgesia
etomidate
324
#1 choice for induction of hemodynamically unstable patients
etomidate
325
Metabolized rapidly by hepatic and plasma esterases and does not accumulate
etomidate
326
why is etomidate CRI containdicated
adrenal suppression
327
ultra short acting barbiturate
thiopental
328
distribution order for thiopental
1. Vessel rich group (CNS)
2. Muscle group
3. Fat group
329
T/F
| thiopental has slow hepatic metabolism and in contraindicated for C-sections and for TIVA
TRUE
330
how does thiopental cause hypotension
Negative inotropy (more than propofol)
vasodilation (less than propofol)
Arrhythmogenic
331
T/F
| ketamine decreases cerebral blood flow
false - increases
332
T/F
| ketamine has analgesic effect
TRUE -- but not as strong as opioids `
333
ketamine CV effects
Indirectly: catecholamine release: increases in HR and contractility
Directly: negative inotropy
334
this drug is useful in asthma patients due to the bronchodilation effect
ketamine
335
Contraindicated to use with corneal damage
ketamine
336
anesthesia is maintained using an inhalational agent
inhalational anesthesia
337
anesthesia is maintained using only intravenous agents
(Total Intravenous Anesthesia): TIVA
338
anesthesia is maintained using both intravenous and inhalational agents
PIVA (Partial Intravenous Anesthesia)
339
propofol unit dose
Propofol 1 mg/kg
340
alfaxalone unit dose
Alfaxalone 0.5 mg/kg
341
T/F
| The elimination half-life changes with the duration of infusion
true
342
T/f
| an ideal tiva agent will have an active metabolite
false
343
TIVA components
anesthetics
analgesics
adjuvants
344
Most common TIVA for small animals
Propofol – fentanyl TIVA
Propofol CRI: 6 - 24 mg/kg/hour
Fentanyl CRI: 0.018 – 0.042 mg/kg/hour
345
alfaxafole tiva
Dogs: 4 - 7 mg/kg/hour CRI
Cats: 5 - 8 mg/kg/hour CRI
can be combined with opioids for analgeics
346
why is etomidate unsuitable for TIVA
Inhibition of cortisol secretion
| Accumulation of propylene glycol (adjuvant)
347
Used to relief abdominal pain in colic horses and Abdominal and neuropathic pain in dogs
Lidocaine CRI
348
why is lidocaine cri contraindicated in cats
of potential cardiotoxic effects
349
T/F
| lidocaine CRI has a wide thearapeutic window
false
350
what is the MLK infusion
morphine
lidocaine
ketamine
highly effective analgesic
skip the lidocaine in cats
351
what drug category is a good anagesic but will not not reduce the MAC in horses
opioids
352
dexmedetomidine dose
Dose: 1 – 3 μg/kg/hour iv
353
Can be used in small animal medicine for its sedative and analgesic properties
dexmedetomidine
354
this drug when used CRI in horses can reduce the MAC by 20-30%
dexmedetomidine
355
dexmedetomidine CRI dose horses
CRI: 3.5 μg/kg/hour iv
356
this gas accumulates in closed gas spaces
N2O
357
Low blood-gas PC (0.47)
N2O
358
T/F
| N2o has strong analgesic
false mild
359
Pressure exerted by vapor molecules when liquid and vapor phases are in equilibrium
vapor pressure
360
needs an electric heated vapoizer
desflurane
361
Boiling point (23.5 C) is close to room temperature
desflurane
362
what is saturated vapor pressure
Vapors have a maximum administration percentage
363
Isofluranes saturated vapor pressure
Iso 32%
364
T/F
| The anesthetic in the alveolar gas represents brain concentration
TRue
365
T/F
| anesthetic dissolved in blood is active
FALSE -- inactive
366
Describes amount of an anesthetic in the blood vs. alveolar gas at equal partial pressure
Blood-gas partition coefficient
367
list the inhalnts in order from most to least soluble
most - halothane, iso, sevo, des (least)
more soluble = higher blood gas PC
368
a ____ blood gas PC has a long induction and recovery
high
369
does a low or high blood gas PC take shorter time required to attain a partial pressure in the brain
LOW
370
blood gas PC where More anesthetic dissolved in blood at
| equal partial pressure (less in alveoli)
high
371
blood gas pc where Less anesthetic dissolved in blood at
| equal partial pressure (more in alveoli)
low
372
uptake of inhalants flow
Vaporizer-- breathing circuit -- alveoli -- arterial blood --
brain
373
_______ = gas delivery to alveoli – removal by A
| blood from lungs
PA
374
ways to increase PA
1. INCREASE anesthetic delivery to alveoli
| 2. DECREASE removal from alveoli
375
two ways to increase alveolar delivery
Increase inspired anesthetic concentration (PI)
| increase alveolar ventilaton
376
how to increase alveolar ventilation
Increase minute ventilation
| Decrease dead space ventilation
377
how to Increase inspired anesthetic concentration (PI)
Increase vaporizer setting
Increase fresh gas flow
Decrease breathing circuit volume
378
T/F
Patients with low CO will have a faster
rise of P A
TRUE
379
T/F
| Decrease blood solubility of anesthetic will decrease removal from alveoli
true
380
three ways to quickly decrease pa
Turn off vaporizer
Disconnect patient and flush O2
Turn up O2 flow
381
define MAC
Minimum alveolar concentration of an anesthetic that prevents movement in 50% of patients exposed to a noxious stimulus
382
T/F
| high MAC = High potency
false -- low potency
383
Myopathy occurring in genetically predisposed pigs
malignant hyperthermia
384
first sign of malginant hyperthermia
First sign is often a rapid increase in EtCO2
385
drug tx for malignany hyperthermia
dantrolene – muscle relaxant
386
MAP<60 mmHg (small animal)
HYPOTENSION -- first step is to turn down the vaporizer
387
possibilities of a CO2 rebreathing wave form
```
Possibilities:
1. Stuck insp/exp valves
2. Exhausted soda lime
3. Inadequate O2 flow in a non-rebreathing
system
```
