Anesthesia case discussion
Caleb Coursey, EMT-P
Tina Brunnet, RVT
The dosages / charts below will be discussed in the lecture. This is simple a tool to use
a reference. While all of the provided information has been reviewed, it is important to
remember to double check dosages / concentrations to avoid medication errors.
ALPHA 2 AGONIST
Dexmedetomidine (DexdomitorR; 0.5 mg/ml) - An alpha-2 agonist (D-isomer)
approved for use as a sedative and analgesic in dogs and cats (IV use in dogs, IM
use in cats). Approximately twice as potent as medetomidine. Common dose range
is 1Xylazine (RompunR; LA preparation = 100 mg/ml; SA preparation = 20 mg/ml)
 Pre-anesthetic - 0.22 to 2.2 mg/kg IM or SC
 Lower doses appear to be associated with fewer undesirable side effects than
higher doses.
 0.22 mg/kg (0.1 mg/lb) IV or 0.55 mg/kg (0.25 mg/lb) IM produces effective
sedation in dogs and cats
ANTICHOLINERGICS
Atropine (0.5 mg/ml) - 0.044 mg/kg (0.02 mg/lb) SC; if an IV anticholinergic is
needed, one-third to one-half the dose is usually administered.
Glycopyrrolate (Robinul-V®, 0.2 mg/ml); 0.011 mg/kg (0.005 mg/lb) SC or IM;
glycopyrrolate is the anticholinergic drug of choice in most (non-emergency)
situations.
BENZODIAZEPINES
Diazepam (Class IV Controlled Substance; Valium® or generic diazepam; 5 mg/ml)
- 0.1 to 0.44 mg/kg IV or IM; do not administer diazepam SC. Diazepam IV may
cause tranquilization, no apparent effect, or some degree of excitement, especially
in healthy mature animals. Its IV administration may reduce the dose of a drug used
for induction of anesthesia.
Midazolam (Class IV Controlled Substance; Versed® or generic midazolam; 5
mg/ml) - 0.1 to 0.44 mg/kg IV, IM or SQ; as with diazepam, may cause
tranquilization, no apparent effect, or some degree of excitement, especially in
healthy mature animals. Its IV administration may reduce the dose of a drug used for
induction of anesthesia.
COMMON INDUCTION AGENTS
Etomidate (Amidate®; 2 mg/ml) An imidazole - 1 to 3 mg/kg IV for induction of
anesthesia, usually after premedication with an opioid and/or diazepam (to prevent
undesirable effects including myoclonus, excitement and vomiting that may occur
without premeds).
Alfaxalone (Alfaxan®; 10mg/ml) A water-soluble neurosteroidal anaesthetic –
Canine 1-3 mg/kg IV & Feline 2-5 mg/kg IV for induction and intubation. Usually
after premedication with an opioid and/or a benzodiazepine. It is advisable to stay
towards the lower end of the dose range when used in conjunction with opioids &
benzodiazepines.
Propofol (Propoflo®; PropoFlo28; 10 mg/ml) an alkylphenol - 2 to 6 mg/kg IV for
induction and intubation. Usually, administered after premedication with an opioid or
tranquilizer. Given by slow injection (60-90 sec) for best effect and to minimize risks
of apnea.
DISSOCIATIVE AGENT
Ketamine (Class III Controlled Substance; Ketaset®; 100 mg/ml)
 Premedication in healthy cats: 4.4 to 8.8 mg/kg IM; often used with other
premeds since it has no intrinsic muscle relaxant properties. 5 mg/kg produces
pretty good cooperation (IM)
 Complete chemical restraint or light anesthesia in healthy cats: 11 to 22 mg/kg
IM; often used in combination with other drugs.
 As an intravenous induction drug:
1. Dose range: 2 to 11 mg/kg
2. Usually administered with an equal volume of diazepam (≈ 0.2 to 0.5
mg/kg); mixed in the same syringe. Practitioner dose is 1 ml/20 lbs IV of
1:1 combination.
3. Effective in both cats and dogs; tends to produce smoother inductions with
a lower total dose if animals are premedicated (e.g., butorphanol,
hydromorphone, acepromazine, or other tranquilizers or sedatives)
Telazol (Class III Controlled Substance;100 mg/ml)
 Mixture of tiletamine and zolazepam
 IV induction - 1.1 to 3.3 mg/kg IV
 Premedication - 2.2 to 6.6 mg/kg IM
MIXED KAPPA AGONIST/ MU ANTAGONIST
Butorphanol (Class IV Controlled Substance; Torbugesic®; 10 mg/ml); 0.2 to 0.4
mg/kg IV, IM, SC. The maximum dose varies with clinicians' preferences. Some
anesthesiologists recommend a maximum dose of 10 mg in large dogs. Short acting
analgesia
MU OPIOD AGONIST
Fentanyl (Class II Controlled Substance; SublimazeR, 50 µg/ml) - 2 to 6 µg/kg IV
for pre-anesthetic sedation; generally lower end of range used for cats
Hydromorphone (Class II Controlled Substance; 2 mg/ml) - 0.1 mg/kg. May be
given IM or SC for premedication. May be used IV for intra-operative analgesia.
Dose in cats is 0.05-0.1 mg/kg.
Methadone (Class II Controlled Substance; 10mg/mL) – 0.1 – 0.5 mg/kg, IV, IM, or
SQ. Typical dose is 0.2mg/kg SQ or IV for pre-med and post-operative
pain. Duration of effect is 4 – 6 hours
Morphine (Class II Controlled Substance; 0.4-1 mg/kg IM; normally, morphine is not
administered IV because it may induce hypotension caused by histamine release.
DuramorphR (Class II Controlled substance; 10-ml ampoules; 0.5 mg/ml) has no
preservatives and is used for epidural administration (0.1 mg/kg) to provide
analgesia.
Oxymorphone Class II Controlled Substance; 1 – ml ampoules 1.0 mg/ml) - 0.05 to
0.1 mg/kg IV, IM, or SC; generally a maximum dose of 4 mg. For IV administration,
use slow injection technique and lower doses rather than rapid bolus technique.
Availability may vary.
Oxymorphone has no preservatives and is used for epidural administration (0.1
mg/kg) to provide analgesia.
Remifentanil (Class II Controlled Substance; 1mg powder for injection). 3mcg/kg/hr
to 36 mcg/kg/hr. Typical starting does is 5mcg/kg/hr. Must be used as a CRI as
duration of effect is approximately 3 minutes.
PARALYTICS
Cisatracurium (Nimbex®, 2mg/ml) – 0.1 mg/kg IV. A nondepolarizing
neuromuscular blocker, duration of action is approximately 20 minutes. Patient
must be under general anesthesia and mechanically ventilated.
Pancuronium Bromide (Pavulon®; 1mg/ml & 2mg/ml) - 0.06 mg/kg. A
nondepolarizing neuromuscular blocker, duration of action is approximately 40
minutes. Patient must be under general anesthesia and mechanically
ventilated.
PARTIAL MU AGONIST
Buprenorphine (Class III Controlled Substance; BuprenexR; 300 µg/ml); 10 to 20
µg/kg IV, IM, or SC. Longer acting analgesia good for mild to moderate pain. Good
in cats.
PHENOTHIAZINE
Acepromazine (PromAceR, 10 mg/ml) – 0.01-0.05 mg/kg IV, IM, or SC; in most
cases, the maximum dose is 1 mg. ** Note that the concentration of the
commercial preparation of acepromazine is 10 mg/ml. The preparation that we
normally have available in the small animal anesthesia area is 1 mg/ml. **
REVERSAL AGENTS
Atipamezole (AntisedanR; 5 mg/ml) - An alpha-2 antagonist approved for the
antagonism of medetomidine and dexmedetomidine in the dog. Atipamezole has not
been evaluated as a routine dexmedetomidine reversal agent in cats. See the
package insert for dosage recommendations (usually equal volume to medetomidine
dose used).
Edrophonium Chloride (Tensilon®, Enlon®; 10 mg/ml) for antagonism of
nondepolarizing blocking agents. Preferred treatment. Give 0.5 mg/kg IV give
slowly over 2-5 minutes. Bradycardia can be seen if given too quickly.
Nalbuphine (NubainR; 20 mg/ml) - for partial opioid antagonism
 Dosage - 0.55 to 2.2 mg/kg
 Dilute 1 ml nalbuphine with saline to a total volume of 10 ml, and administer IV
slowly and to effect; nalbuphine can be administered SC for a slower onset and
longer duration.
Naloxone (NarcanR; 0.4 mg/ml) for complete opioid antagonism
 General dosage: 0.044 mg/kg
 IV: Dilute 1 ml (0.4 mg) with 9 ml of saline; administer slowly to effect; administer
the remainder SC to increase the duration of effect.
 SC: Administer the appropriate dosage of naloxone SC for a slower onset and
longer effect.
 The duration of action of naloxone is relatively short, and its effectiveness will
depend on the opioid being antagonized and the time that has passed since the
opioid was administered.
Pyridostigmine Bromide (Mestinon®; 5 mg/ml) For antagonism of nondepolarizing
blocking agents. Give 0.1 – 0.3 mg/kg slowly over 10 minutes IV. Give atropine or
glycopyrrolate prior to administration to prevent sever bradycardia.
Tolazoline (PriscolineR; 25 mg/ml) (TolazineR; 100 mg/ml) - For antagonism of
alpha-2 drugs (e.g., xylazine). Usually dosed at 2 mg/kg slowly IV to effect. Can be
diluted with saline to facilitate controlled IV administration. Rapid administration or
overdosing can lead to excitement. The dosage needed will vary with the original
dose of xylazine and the amount of time that has passed since the xylazine was
administered.
Yohimbine (YobineR) (2 mg/ml) - For antagonism of alpha-2 drugs (e.g., xylazine).
The dose on the label is 0.11 mg/kg (0.05 mg/lb) IV for dogs. The drug should be
administered slowly and to effect, and the drug can be diluted with saline to facilitate
controlled IV administration. Rapid administration or overdosing may lead to
excitement. The dosage needed will vary with the original dose of xylazine and the
amount of time that has passed since the xylazine was administered.
Ketamine Infusion
Dilute Ketamine to 10mg/ml
Loading dose: 0.5mg/kg IV
Intraop Dose: 10 mcg/kg/min
Weight in Kg
Dose: 10mcg/kg/min Milliliters per hour
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
0.06
0.12
0.18
0.24
0.30
0.36
0.42
0.48
0.54
0.60
0.66
0.72
0.78
0.84
0.90
0.96
1.0
1.1
1.1
1.2
1.3
1.3
1.4
1.4
1.5
1.6
1.6
1.7
1.7
1.8
1.9
1.9
2.0
2.0
2.1
2.2
2.2
2.3
2.3
2.4
Postop Dose: 2 mcg/kg/min
Dose: 2mcg/kg/min Milliliters per
hour
0.01
0.02
0.04
0.05
0.06
0.07
0.08
0.10
0.11
0.12
0.13
0.14
0.16
0.17
0.18
0.19
0.20
0.22
0.23
0.24
0.25
0.26
0.28
0.29
0.30
0.31
0.32
0.34
0.35
0.36
0.37
0.38
0.40
0.41
0.42
0.43
0.44
0.46
0.47
0.48
Lidocaine Infusion
Concentration: 20 mgs/ml
Loading dose: 1 mg/kg IV
Weight in Kg
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Intraop analgesic: 25-50 mcg/kg/min
Cardiac Arrythmias: 50 mcg/kg/min – 100mcg/kg/min
Dose: 25mcg/kg/min Dose: 50mcg/kg/min Dose: 75 mcg/kg/min
Milliliters per hour
Milliliters per hour
Milliliters per hour
0.08
0.15
0.23
0.30
0.38
0.45
0.53
0.60
0.68
0.75
0.83
0.90
0.98
1.1
1.1
1.2
1.3
1.4
1.4
1.5
1.6
1.7
1.7
1.8
1.9
2.0
2.0
2.1
2.2
2.3
2.3
2.4
2.5
2.6
2.6
2.7
2.8
2.9
2.9
3.0
0.15
0.30
0.45
0.60
0.75
0.90
1.1
1.2
1.4
1.5
1.7
1.8
2.0
2.1
2.3
2.4
2.6
2.7
2.9
3.0
3.2
3.3
3.5
3.6
3.8
3.9
4.1
4.2
4.4
4.5
4.7
4.8
5.0
5.1
5.3
5.4
5.6
5.7
5.9
6.0
0.23
0.45
0.68
0.90
1.1
1.4
1.6
1.8
2.0
2.3
2.5
2.7
2.9
3.2
3.4
3.6
3.8
4.1
4.3
4.5
4.7
5.0
5.2
5.4
5.6
5.9
6.1
6.3
6.5
6.8
7.0
7.2
7.4
7.7
7.9
8.1
8.3
8.6
8.8
9.0
Dose: 100mcg/kg/min
Milliliters per hour
0.30
0.60
0.90
1.2
1.5
1.8
2.1
2.4
2.7
3.0
3.3
3.6
3.9
4.2
4.5
4.8
5.1
5.4
5.7
6.0
6.3
6.6
6.9
7.2
7.5
7.8
8.1
8.4
8.7
9.0
9.3
9.6
9.9
10.2
10.5
10.8
11.1
11.4
11.7
12.0
Fentanyl Infusion
Concentration: 50 mcg/ml
Loading Dose: 2-5 mcg/kg IV
Wt Kg
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Dose: 3
mcg/kg/hr
Milliliters per hour
0.06
0.12
0.18
0.24
0.30
0.36
0.42
0.48
0.54
0.60
0.66
0.72
0.78
0.84
0.90
0.96
1.0
1.1
1.1
1.2
1.3
1.3
1.4
1.4
1.5
1.6
1.6
1.7
1.7
1.8
1.9
1.9
2.0
2.0
2.1
2.2
2.2
2.3
2.3
2.4
Anaglesic: 3-10 mcg/kg/hr
Dose: 4
mcg/kg/hr
Milliliters per
0.08
0.16
0.24
0.32
0.40
0.48
0.56
0.64
0.72
0.80
0.88
0.96
1.0
1.1
1.2
1.3
1.4
1.4
1.5
1.6
1.7
1.8
1.8
1.9
2.0
2.1
2.2
2.2
2.3
2.4
2.5
2.6
2.6
2.7
2.8
2.9
3.0
3.0
3.1
3.2
Dose: 5
mcg/kg/hr
Milliliters per
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.0
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2.0
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
3.0
3.1
3.2
3.3
3.4
3.5
3.6
3.7
3.8
3.9
4.0
Cardiac TIVA: 48 mcg/kg/hr
Dose: 10
mcg/kg/hr
Milliliters per
0.20
0.40
0.60
0.80
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
2.6
2.8
3.0
3.2
3.4
3.6
3.8
4.0
4.2
4.4
4.6
4.8
5.0
5.2
5.4
5.6
5.8
6.0
6.2
6.4
6.6
6.8
7.0
7.2
7.4
7.6
7.8
8.0
Dose: 48
mcg/kg/hr
Milliliters per
0.96
1.9
2.9
3.8
4.8
5.8
6.7
7.7
8.6
9.6
10.6
11.5
12.5
13.4
14.4
15.4
16.3
17.3
18.2
19.2
20.2
21.1
22.1
23.0
24.0
25.0
25.9
26.9
27.8
28.8
29.8
30.7
31.7
32.6
33.6
34.6
35.5
36.5
37.4
38.4
Remifentanil Infusion
Diluted to a concentration to 50 mcg/ml
Wt Kg
Dose: 0.05
mcg/kg/min
Milliliters per
hour
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
0.06
0.12
0.18
0.24
0.30
0.36
0.42
0.48
0.54
0.60
0.66
0.72
0.78
0.84
0.90
0.96
1.0
1.1
1.1
1.2
1.3
1.3
1.4
1.4
1.5
1.6
1.6
1.7
1.7
1.8
1.9
1.9
2.0
2.0
2.1
2.2
2.2
2.3
2.3
2.4
Dose: 0.1
Dose: 0.2
Dose: 0.3
Dose: 0.4
Dose: 0.5
Dose: 0.6
mcg/kg/min mcg/kg/min mcg/kg/min mcg/kg/min mcg/kg/min mcg/kg/min
Milliliters per Milliliters per Milliliters per Milliliters Milliliters per Milliliters
hour
hour
hour
per hour
hour
per hour
0.12
0.24
0.36
0.48
0.60
0.72
0.84
0.96
1.1
1.2
1.3
1.4
1.6
1.7
1.8
1.9
2.0
2.2
2.3
2.4
2.5
2.6
2.8
2.9
3.0
3.1
3.2
3.4
3.5
3.6
3.7
3.8
4.0
4.1
4.2
4.3
4.4
4.6
4.7
4.8
0.24
0.48
0.72
0.96
1.2
1.4
1.7
1.9
2.2
2.4
2.6
2.9
3.1
3.4
3.6
3.8
4.1
4.3
4.6
4.8
5.0
5.3
5.5
5.8
6.0
6.2
6.5
6.7
7.0
7.2
7.4
7.7
7.9
8.2
8.4
8.6
8.9
9.1
9.4
9.6
0.36
0.72
1.1
1.4
1.8
2.2
2.5
2.9
3.2
3.6
4.0
4.3
4.7
5.0
5.4
5.8
6.1
6.5
6.8
7.2
7.6
7.9
8.3
8.6
9.0
9.4
9.7
10.1
10.4
10.8
11.2
11.5
11.9
12.2
12.6
13.0
13.3
13.7
14.0
14.4
0.48
0.96
1.4
1.9
2.4
2.9
3.4
3.8
4.3
4.8
5.3
5.8
6.2
6.7
7.2
7.7
8.2
8.6
9.1
9.6
10.1
10.6
11.0
11.5
12.0
12.5
13.0
13.4
13.9
14.4
14.9
15.4
15.8
16.3
16.8
17.3
17.8
18.2
18.7
19.2
0.60
1.2
1.8
2.4
3.0
3.6
4.2
4.8
5.4
6.0
6.6
7.2
7.8
8.4
9.0
9.6
10.2
10.8
11.4
12.0
12.6
13.2
13.8
14.4
15.0
15.6
16.2
16.8
17.4
18.0
18.6
19.2
19.8
20.4
21.0
21.6
22.2
22.8
23.4
24.0
0.72
1.4
2.2
2.9
3.6
4.3
5.0
5.8
6.5
7.2
7.9
8.6
9.4
10.1
10.8
11.5
12.2
13.0
13.7
14.4
15.1
15.8
16.6
17.3
18.0
18.7
19.4
20.2
20.9
21.6
22.3
23.0
23.8
24.5
25.2
25.9
26.6
27.4
28.1
28.8
Dobutamine/Dopamine Infusion
Dose: 1-10 ug/kg/min
1 drop/4s = 2ug/kg/min
Add dobutamine to a 250mL bag of 5% Dextrose or 0.9% NaCl
Administer with 60 drop/ml dripset at 1 drop/4s, then titrate to effect
Weight (Kg)
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
35
40
45
50
ug/min
4
8
12
16
20
24
28
32
36
40
44
48
52
56
60
70
80
90
100
ug/ml
16
32
48
64
80
96
112
128
144
160
176
192
208
224
240
280
320
360
400
mg/250ml
4
8
12
16
20
24
28
32
36
40
44
48
52
56
60
70
80
90
100
Dobutamine (mL)
0.32
0.64
0.96
1.3
1.6
1.9
2.2
2.6
2.9
3.2
3.5
3.8
4.2
4.5
4.8
5.6
6.4
7.2
8
Dopamine (mL)
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
1.2
1.3
1.4
1.5
1.75
2
2.25
2.5
Dopamine Dose Ranges:
Dopamine is a mixed dopaminergic, beta agonist and alpha 1 agonist with dose dependant results.
At the lower dosage range of 1-3 mcg/kg/min will increase renal and splanchnic vessel dilation due
to the dopaminergic effect – resulting in increased renal blood flow. The mid-range dose of 5-8
mcg/kg/min results in mild beta 1 and alpha 1 properties resulting in positive inotropy,
chronotropy and vasoconstriction. The high range of 8 – 20 mcg/kg/min of dopamine results in a
strong alpha 1 response and acts as a potent vasoconstrictor.