Ch.23 Chemical Restraint for Standing Procedures

Question 1

Goal of chemical restraint for standing sx

Answer 1

Keep horse calm, sedated, indifferent to noxious and external stimuli and physical stimulation

Question 2

Starting doses for Medetomidine and Dexmedetomidine

Answer 2

Med - 5 - 7 ug/kg
Dexmed 3 - 5 ug/kg

Question 3

How are the effects of alpha 2 adrenoreceptor agonists elicited

Answer 3

Activation of alpha 2 Adrenoreceptors located on the Locus Coeruleus in the pons of the brainstem

Question 4

What is responsible for the increased sensitivity to touch associated with alpha 2 agonists

Answer 4

Modification of activity of the fast conducting non-nociceptive afferent Beta fibres

Question 5

How long post administration are peak effects of Alpha2 reached after IV

Answer 5

3 - 20 mins
Longer acting such as dobutamine and romifidine may take longer

Question 6

What dose is advised when reducing alpha 2

Answer 6

1/4 to 1/2 of the initial dose

Question 7

How do IM does differ for A2

Answer 7

Use twice the IV dose and 30 - 60 mins for peak effect

Question 8

Sublingual Detomidine dose and time

Answer 8

0.04mg/kg
45 mins

Question 9

At a dose of 0.02mg/kg iv for a routine dental how many horses were noted to fall down

Answer 9

30%

Question 10

What dose of Detomidine for a horse following exertion exercise

Answer 10

0.04mg/kg

Question 11

Normal dose of Detomidine IV

Answer 11

0.01-0.02mg/kg/iv

Question 12

Dose of romifidine

Answer 12

0.08 - 0.12 mg/kg iv

Question 13

Recommended dose of Xylazine with Butorphanol

Answer 13

0.5
0.02

Question 14

Recommended dose of Xylazine with Methadone

Answer 14

0.7
0.1

Question 15

Recommended dose of Detomidine with Butorphanol

Answer 15

0.01 - 0.03
0.01 - 0.025

Question 16

Recommended dose of Detomidine with Buprenorphine

Answer 16

0.01
0.005

Question 17

Effects of A2s on serum insulin

Answer 17

Decrease - hyperglycaemia

Question 18

Controlling persistent seizures post intra carotid administration of A2

Answer 18

Benzodiazepines
Guaifenesin
Thiopental

Question 19

Why d stressed horses not sedate well

Answer 19

Production of endogenous catecholamines

Question 20

Dosing mules/donkeys/draft breeds with alpha 2s

Answer 20

Mules/Donks double dose
Draft 1/2 dose

Question 21

What drugs should never be administered IV following alpha 2 tx to avoid fatal arrhythmia

Answer 21

Potentiated sulfonamides

Question 22

Alpha2 not recommended in foals under what age

Answer 22

<14 days
or sick foals <3 months

Question 23

Benefits of combining acepromazine with an alpha 2

Answer 23

Prevent vasoconstriction
Improved CO and decreased drop in HR
Better arterial oxygenation

Question 24

Antagonist for benzodiazepines and dose

Answer 24

Flumazenil 0.04mg/kg/iv

Question 25

Sedation foals <2 weeks or <3 months and v sick

Answer 25

Midazolam 0.05 - 0.2mg/kg/iv Diazepam 0.05 - 0.3mg/kg/iv

Question 26

2-3 month old healthy foal sedation

Answer 26

Xyla/Levomethadone 0.2 - 0.5/0.05 Xyla/Butor 0.2 - 0.5/0.01 - 0.02 mg/kg/iv

Question 27

Dose of ketamine for standing sedation

Answer 27

0.1mg/kg

Question 28

What are the frequently used alpha 2 antagonists

Answer 28

Yohimbine Tolazoline Atipamazole - most freq used - severe side effects only use in emergency

Question 29

What precaution should be used for A2 antagonists

Answer 29

If selective Alpaha2/Alpha1(medetomidine) agonist used, use a lower dose of antagonist If agonist given >45 mins prior - give antagonist IM

Question 30

How much atipamazole is required to reverse 10ug/kg if deteomidine

Answer 30

0.1mg/kg - complete

Question 31

How much atipamazole is required to reverse 20ug/kg of deteomidine

Answer 31

0.16mg/kg

Question 32

How much atipamazole is required to reverse 10ug/kg of medetomidine

Answer 32

0.08mg/kg

Question 33

How much atipamazole is required to reverse medetomididne CRI

Answer 33

0.06mg/kg

Question 34

How much atipamazole is required to reverse 1mg/kg xylazine

Answer 34

0.15mg/kg

Question 35

How much Tolazoline is required to reverse 40ug/kg of detomidine

Answer 35

4mg/kg

Question 36

How much Tolazoline is required to reverse 20ug/kg of detomidine

Answer 36

4mg/kg

Question 37

How much Tolazoline is required to reverse Xylazine CRI

Answer 37

7.5mg/kg

Question 38

How much Yohimbine is required to reverse 0.03/kg of detomidine

Answer 38

0.2mg/kg

Question 39

How much Yohimbine is required to reverse Xylazine CRI

Answer 39

0.12mg/kg

Question 40

Mechanism of action of phenothiazines

Answer 40

Block dopamine receptors in the basal ganglia and limbic system

Question 41

Pros of phenothiazines

Answer 41

Antiarrhythmic Antifibrillatory effects Decrease anaesthetic risk Reduces opioid excitation

Question 42

Doses of Acepromazine

Answer 42

0.02 - 0.05mg/kg iv/im 0.1 mg/kg po

Question 43

When are the peak effects of Acepromazine seen

Answer 43

10-30 mins iv 20-40 mins im 60 mins po

Question 44

Whats responsible for the hemodynamic effects of phenothiazines

Answer 44

Alpha1 adrenergic blocking activity

Question 45

What is epinephrine reversal

Answer 45

Fall in blood pressure owing to large quantity of circulating epinephrine in stressed animals ACP blocks Alpha1 adrenoreceptors B2 adrenoreceptor vasodilation caused by epinephrin

Question 46

Effect of ACP of PCV

Answer 46

20% decrease in PCV following clinical use of ACE Splenic relaxation and RBC sequestration

Question 47

Mechanism of action of benzodiazepines

Answer 47

Facilitate actions of GABA (y-aminobutyric acid) the principle neurotransmitter in the CNS

Question 48

What dose of diazepam can be used to decrease jaw/tongue tone or increase stallion libido

Answer 48

0.01mg/kg/iv

Question 49

If IM is only route use diazepam or midazolam?

Answer 49

Midazolam