Pre-Medication

Question 1

What is the function of premedication?

Answer 1

Produces a calming effect or sedation
Reduces stress and eliminates pain
Produces muscle relaxation
Reduces adverse effects
Lowers drug doses of GA
Minimises autonomic reflex activity

Question 2

Groups of premed?

Answer 2

1. Anticholinergics
2. Tranquillisers
3. Mild-tranquillisers
4. Sedatives
5. Opioids

Question 3

Anticholinergics

Answer 3

e. g. Atropine and scopolamine
- Reduce glandular secretions of RT and GIT, oral and nasal cavity
- Can cause colic in horses by decreasing intestinal motility
- Bronchodilation and mydriasis
- Inhibits bradycardia

Question 4

Tranquillisers?

Answer 4

Acepromazine, promazine

• Calming and neurologic effect
• May cause hypotension
• 4-8 hours clinical effect

Question 5

Minor tranquilisers

Answer 5

Diazepam

• Muscle relaxation
• Anticonvulsant
• Minimally hypotensive
• Slow IV injection
• 1-4 hours effect

Question 6

Sedatives?

Answer 6

Xylazine, medetomidine, detomidine
- Calming effect, muscle relaxation and analgesia
Xylazine - 20-40m
Medetomidine - 45-90
Detomidine - 90-120m

Question 7

Opioids?

Answer 7

Morphine (2-4h), fentanyl (45-60m), butorphanol (1-2h), tramadol

• Inhibit neurones
• agonists, partial agonists, antagonists
• decrease anxiety
• sedation and chemical restraint
• analgesia

Question 8

Cardiopulmonary effects of opioids?

Answer 8

Bradyarrhythmia
Histamine release - hypotension
Respiratory depression

Question 9

ADR of opioids

Answer 9

• V + D
• Constipation with continual use
• Excitation at high doses in cat, horse and pig
• Abuse potential