Premedication and Injectable Anesthesia

Question 1

What is ASA classification system?

Answer 1

Assessment of health of patient and anesthesia risk
1- Normal, healthy patient for elective procedure
2- Patient with mild systemic disease
3- Patient with sever systemic disease that is a constant threat to life
4- Moribund, not expected to live 24hrs with or without surgery
E- emergency

Question 2

What are the main goals of pre-anesthetics?

Answer 2

Calm and tranquilize patient
Provide chemical restraint
Reduce amount of inhalant needed
Analgesia
Prevent bradycardia
Decrease salivation/airway secretion
Improve recovery (less delirium)

Question 3

What is the function of anticholinergics?

Answer 3

Inhibit excessive parasympathetic activity by blocking Ach
Will increase HR, decrease GI motility and salivation

Use in surgeries in areas of high vagal activity

Question 4

What are examples of anticholinergics?

Answer 4

Atropine - faster onset, shorter duration, cause tachycardia, crosses BBB

Glycopyrrolate- slower onset, longer duration, less tachycardia, does not cross BBB

Question 5

What drug elicits an intense reaction in Boxers and may cause penile paralysis in stallions?

Answer 5

Acepromazine

Question 6

What drug provides muscle relaxation but no analgesia?

Answer 6

Acepromazine

Question 7

What are examples of muscle relaxants/benzodiazepines?

Answer 7

Diazepam, Midazolam, Guaifenesin

Question 8

What are characteristics of Diazepam?

Answer 8

Oily, propylene glycol
Pain on IM injection
Precipitates with other drugs (except ketamine)
Metabolized by liver
Less expensive

Question 9

What are characteristics of Midazolam?

Answer 9

Water soluble
No pain on injection
No precipitation
Safer for liver than diazepam
More expensive

Question 10

What is Guifenesin?

Answer 10

Benzo
Used for induction (with ketamine) in horses, small ruminants, camelids
Part of "triple drip" in horses
Acts centrally for mild sedation
No reversal
May cause urticaria

Question 11

What is the mechanism of action of dissociatives?

Answer 11

Act on glutamate binding sites, are NMDA-receptor antagonists, and potentiates GABA inhibition
Superior somatic and less visceral analgesia
Stimulates sympathetic tone (will inc. HR and BP)

Question 12

What are examples of dissociatives?

Answer 12

Ketamine

Telazol

Question 13

In what type of patients should you use Alfaxalone?

Answer 13

Aggressive cats

Cats with HCM

Question 14

What kind of drug is Alfaxalone?

Answer 14

Neuroactive steroid

Question 15

What drugs have a biphasic effect of blood pressure?

Answer 15

Alpha 2 agonists

Question 16

What is the order of species sensitivity to alpha 2 agonists?

Answer 16

Ruminants > camelids < small ruminants < equine < small animal < pigs < lab animals (rats, mice)

Question 17

What is neuroleptanalgesia?

Answer 17

Opioid + sedative or tranquilizer

Question 18

How are opioids classified?

Answer 18

By receptor and if they are a full agonist, partial agonist, or antagonist

Question 19

Why does administration of propofol sometimes result in excitation?

Answer 19

It inhibits inhibitory neurotransmitter before excitatory

Question 20

What drugs are typically used along with ketamine and why?

Answer 20

Benzodiazepines for muscle relaxation

Question 21

What drug causes sympathetic stimulation and myocardial depression?

Answer 21

Ketamine

Question 22

What drug is good for patients with CV disease but also causes adrenal suppression?

Answer 22

Etomidate

Don’t use in shock patients!