Induction Agents

Question 1

induction agent

Answer 1

chemical agent that allows intubation which bridges the gap between premed and inhalant anesthetics

Question 2

4 Most Commonly Seen Induction Agents in Veterinary Practice

Answer 2

1. Propofol
2. Alfaxalone
3. Etomidate
4. Ketamine

Question 3

Two Possible MOAs for Induction Agents

Answer 3

1. GABAa agonist
2. NMDA antagonist

Question 4

What’s the right propofol dose?

Answer 4

titrate to effect

Question 5

Can you give Propoflo28 to cats?

Answer 5

Only once! Cats cannot metabolize the benzyl alcohol preservative that is added to increase shelf life.

Question 6

main inhibitory NT of the CNS

Answer 6

GABA

Question 7

main excitatory NT of the CNS

Answer 7

NMDA (glutamate)

Question 8

Which of the four main induction agents is an NMDA antagonist?

Answer 8

ketamine

Question 9

Onset and Duration of Propofol

Answer 9

fast onset, short duration

Question 10

CNS Effects of Propofol

Answer 10

hypnosis, decreased ICP and blood flow, decreased oxygen demand

Question 11

Respiratory Effects of Propofol

Answer 11

depressant (speed and dose dependent)

Question 12

CV Effect of Propofol

Answer 12

depressant

Question 13

inotrope

Answer 13

drug that affects contractility of the heart

Question 14

Does propofol cause hypo or hypertension?

Answer 14

hypotension (transient and dose-dependent, goes away when drug wears off)

Question 15

Is propofol a positive or negative inotrope?

Answer 15

negative

Question 16

Is propofol safe for c-sections?

Answer 16

yes

Question 17

Why is propofol not good for cats?

Answer 17

can cause RBC lysis/Heinz body anemia with repeated administrations

Question 18

Main excretion of propofol?

Answer 18

liver

Question 19

What drug is known as “clear propofol?”

Answer 19

Alfaxalone

Question 20

Can cats have alfaxalone?

Answer 20

yes! Better than propofol because no RBC lysis

Question 21

Can alfaxalone be given IM?

Answer 21

yes

Question 22

Onset and Duration of Alfaxalone

Answer 22

fast onset, short duration

Question 23

Do you see alfaxalone side effects if given IM?

Answer 23

not so much

Question 24

Effects of Propofol and Alfaxalone on Intraocular Pressure

Answer 24

Propofol will decrease IOP, Alfax will increase IOP

Question 25

Etomidate Onset and Duration

Answer 25

fast onset, short duration

Question 26

Etomidate effect on Cardiovascular System

Answer 26

NONE/MINIMAL, good for heart failure, stenosis, etc

Question 27

Why is etomidate not used more if it's so much better for the cardiovascular system?

Answer 27

absolutely must be given with a co-induction agent, can cause stiffness, retching/vomiting, pain on injection, and adrenocortical suppression so overall induction quality is poor

Question 28

NMDA Antagonist

Answer 28

prevents uptake of calcium

Question 29

Cyclohexanes

Answer 29

dissociative anesthetic agents which include ketamine, tiletamine and zolazepam (Telazol)

Question 30

What two induction agents must only be given IV?

Answer 30

propofol and etomidate

Question 31

Routes of Administration of Ketamine

Answer 31

IV, IM, buccal

Question 32

Can ketamine be given alone?

Answer 32

technically yes but it needs a VERY strong premed, otherwise the animal will be too stiff (muscle rigidity)

Question 33

Which induction agent is a CNS stimulant?

Answer 33

ketamine!

Question 34

CNS Effects of Ketamine

Answer 34

dissociation, INCREASED ICP, blood flow, and oxygen demand

Question 35

Respiratory Effects of Ketamine

Answer 35

bronchodilator! (not so much of a depressant comparatively)

Question 36

Can you give cats with HCM ketamine?

Answer 36

NO

Question 37

Overall Cardiovascular Effect of Ketamine

Answer 37

INCREASE because the catecholamine surge from adrenal stimulation overrides the negative inotropic effect

Question 38

Which two agents are safe for c-sections?

Answer 38

propofol and alfaxalone

Question 39

Nystagmus is a side effect of which induction agent?

Answer 39

ketamine (increased IOP)

Question 40

Tiletamine

Answer 40

cyclohexane which is slower to be metabolized than ketamine so it lasts longer (but can be nephrotoxic in rabbits)

Question 41

Benzodiazepines

Answer 41

muscle relaxing agents for co-induction midazolam (water soluble) and diazepam (lipid soluble)

Question 42

Lidocaine

Answer 42

co-induction agent good for analgesia, antiarrhythmic (VPCs), and MAC reductive

Question 43

Main Induction agent in horses?

Answer 43

ketamine, +/- guaifenesin