EL Anaesthesia drugs

Question 1

What are some key interspecies differences in pharmacokinetics /pharmacodynamics?

Answer 1

Anatomy - size, skin etc.
Physiology - organ systems
Behaviour
Genetics

Question 2

What can affect IM injections in birds and reptiles?

Answer 2

Renal portal system

Question 3

What is the renal portal system?

Answer 3

Blood from caudal body drains through kidney before going to heart

Question 4

What can be an issue with subcut injections in cats?

Answer 4

Fibromatous reactions

Vaccine induced sarcomas

Question 5

What is neophobia?

Answer 5

Being unwilling to take in novel substances due to being unable to vomit

Question 6

How does the reticulorumen affect drug administration/absorption in ruminants?

Answer 6

Slow emptying
Poor absorption
Acidic

Question 7

How is the reticulo-omasal orifice important in drug administration/absorption?

Answer 7

Can be used for prolonged delivery devices eg. boluses

Question 8

What about the horses GI tract can affect drug absortion and administration?

Answer 8

Cellulose binding - feed changes bioavailability

Question 9

What is pharmacogenetics?

Answer 9

Study of variability in drug response due to heredity

Question 10

What is pharmacogenomics?

Answer 10

How all genes in the genome may determine drug response

Question 11

What are examples of pharmacogenetics?

Answer 11

Cytochrome P450 in greyhounds

MDR1 in collies

Question 12

What kind of dose extrapolation is most common?

Answer 12

Allometric scaling - weight

Question 13

What are the main categories of drugs used for sedation/pre-meds?

Answer 13

Opioids
Alpha 2 agonist
ACP
Benzodiazepine

Question 14

What are the most common injectable anaesthetic agents?

Answer 14

Propofol and alfaxalone

Ketamine

Question 15

What type of drugs are propofol and alfaxalone?

Answer 15

GABA agonists

Question 16

What is the an injectable anaesthetic agent used in large animals?

Answer 16

Ketamine

Question 17

What are the main drugs used for euthanasia?

Answer 17

Pentobarbital

Somulose

Question 18

What are the ideal factors of an injectable anaesthetic agent?

Answer 18

Rapid onset
Non irritant
Non-cumulative
Good analgesia
Good muscle relaxation
Minimum cardiopulmonary effects

Question 19

Does propofol provide analgesia?

Answer 19

No

Question 20

Is propofol cumulative?

Answer 20

Not in dogs

Yes when infused in cats

Question 21

Does propofol cross BBB?

Answer 21

No

Question 22

Is alfaxalone cumulative?

Answer 22

No

Question 23

What type of drug is ketamine?

Answer 23

NMDA antagonist - dissociative anaesthetic

Question 24

What effect does ketamine have on muscles?

Answer 24

Poor muscle relaxation

Question 25

What effect does ketamine have on the nervous system?

Answer 25

Sympathetic stimulation

Question 26

Does ketamine provide analgesia?

Answer 26

Yes

Question 27

What is the onset of ketamine like?

Answer 27

Slow - loud noises can cause excitement

Question 28

Is alfaxalone an irritant?

Answer 28

No

Question 29

What is ketamine administered with?

Answer 29

Benzodiazepines

Question 30

Why might TIVA be used?

Answer 30

Reduce exposure to inhalant

Question 31

What resp effects does propofol have?

Answer 31

Post induction apnoea common

Question 32

How are propofol, alfaxalone and ketamine metabolised?

Answer 32

Liver

Question 33

What effect does ketamine have on the anaesthetic reflexes?

Answer 33

Central eye and pharyngeal reflexes maintained

Question 34

Which injectable anaesthetic agent has a high plasma protein binding?

Answer 34

Propofol

Question 35

What does vapour mean?

Answer 35

Gaseous state of a substance that at ambient temp and pressure is a liquid

Question 36

What is partial pressure?

Answer 36

Pressure that an individual gas exerts in a mixture of gases

Question 37

What is the partition coefficient?

Answer 37

Ratio of the concentration of a compound in two solvents at equilibrium

Question 38

How does cardiac output affect inhalational agent uptake/onset?

Answer 38

Lower CO is, the faster the onset

Question 39

How does blood gas solubility affect inhalational drug action?

Answer 39

Lower the blood gas solubility, the faster the drug onset and recovery is

Question 40

What factors affect what drugs to give farm animals?

Answer 40

Food producing animals - withdrawal periods, cascade | Pregnancy

Question 41

What sedatives are used in cattle?

Answer 41

Xylazine | Detomidine - not last trimester of pregnancy

Question 42

What sedative is used in pigs?

Answer 42

Azaperone

Question 43

What sedatives are used in sheep?

Answer 43

No sedatives licenced

Question 44

Are opioids given alongside a2 agonists in farm animals?

Answer 44

No

Question 45

What local anaesthetic is used in cattle?

Answer 45

Procaine hydrochloride plus epinephrine bitartrate - IM

Question 46

What is used for sedation in horses?

Answer 46

Acepromazine (ACP) | a2 agonists - xylazine and detomidine

Question 47

Are opioids given alongside a2 agonists in horses?

Answer 47

Yes

Question 48

What opioids are used in horses?

Answer 48

Butorphanol | Buprenorphine

Question 49

Why are opioids given alongside a2 agonists?

Answer 49

Synergistic effect on analgesia | Increased sedation

Question 50

What effects do a2 agonists have on horses?

Answer 50

``` Muscle relaxation Analgesia Bradycardia Sweating Decreased GI motility ```