Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

LEAH FCP > Premedication > Flashcards

Premedication Flashcards

1
Q

What is premedication?

A

Provision of sedation & anxiolysis before induction of anaesthesia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the benefits of premedication?

A

Reduction of dose of induction agent

Reduction of dose of maintenance agent

Provide pre-emptive analgesia & preventive analgesia

Ensure smooth recovery

Prevent side effects associated with other anaesthetic drugs

Can start at home in anxious animals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define pre-emptive analgesia

A

Administration of analgesic drugs prior to onset of noxious stimulation

Benefits:
- Reduces immediate post-operative pain
- Minimises intensity & duration of subsequent pain.
- Easier pain control with analgesics post-surgery.
- Prevents peripheral & central sensitisation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Define multimodal analgesia

A

Combines different analgesics acting via different mechanisms or sites in the nervous system.

Benefits:
- Additive & improved pain relief
- Reduced drug doses minimise side effects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Define preventive analgesia

A

Combines multimodal and pre-emptive analgesia

Continues into the early post-operative period to maintain effective pain control.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe Acepromazine (ACP=

A

A phenothiazine

widely used premed in dogs, cats & horses

Usually used with opioid (neuroleptanalgesia) because synergism occurs

Interferes with dopamine transmission to provide sedation

Can reduce blood pressure & oxygen delivery to tissues
- due to reduction in haemoglobin concentration caused by splenic sequestration of RBC

SC, IM, IV & oral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Define Neuroleptanalgesia

A

state of sedation & analgesia induced by combining neuroleptic (sedative) & opioid analgesic, commonly used for minor procedures & premedication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the most commonly used drugs to produce neuroleptanalgesia

A

Phenothiazine agents
α2-adrenoceptor agonists
Opioid analgesics

Administering these drugs together produces synergistic effects (greater sedation and analgesia than when given individually).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What a-2 agonists are used in small animals

A

Medetomidine & dexmedetomidine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What a-2 agonists are used in horses

A

Xylazine, detomidine & romifidine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What a-2 agonists are used in cattle

A

Xylazine & detomidine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe a-2 agonists

A

Profound cardiovascular effects (dose dependent) & reduction in cardiac output

increased urine output

Produces miosis (pupil constriction), decreased IOP (intraocular pressure) & decreased CBP (ciliary body perfusion) but vomiting possible

Atipamezole is the antagonist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Why are a-2 agonists (e.g. medetomidine & dexmedetomidine) a popular premed?

A

They provide reliable sedation, analgesia, and muscle relaxation.

Dexmedetomidine is often preferred over medetomidine as it excludes biologically inert levomedetomidine.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Why is xylazine not recommended for premed in dogs & cats?

A

Xylazine is associated with higher risk of mortality compared to other α-2 agonists & safer alternatives like dexmedetomidine are available

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How do a-2 agonists cause sedation?

A
  1. α-2 Receptor Activation: Stimulates α-2 adrenoreceptors in CNS
  2. Inhibition of Adenylyl Cyclase: Reduces cyclic adenosine monophosphate (cAMP)
  3. Hyperpolarization: Potassium efflux & calcium channel inhibition prevent calcium entry into nerve terminals
  4. Suppression of Neural Firing: Decreases norepinephrine release in noradrenergic pathways
  5. Reduced Ascending Pathway Activity: Leads to sedation and hypnosis.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What cardiovascular effects do a-2 agonists cause?

A

Initial phase: Intense vasoconstriction, increased blood pressure & reflex bradycardia

Later phase (20–30 min): Vasoconstriction wanes, blood pressure normalizes, but heart rate remains low due to centrally mediated sympatholysis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How do a-2 agonists provide analgesia

A

They inhibit nociceptive neurons in dorsal horn of spinal cord & reduce substance P release

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Describe Benzodiazepines

A

E.g. Midazolam (water soluble), diazepam, zolazepam, alprazolam (others are dissolved in propylene glycol)

Work on GABA

effects:
- anxiolytic
- muscle relaxation
- cardiovascular stability

No analgesia

Suitable for ASA III-V patients

Avoid in healthy patients (causes excitement)

Antagonist is flumazenil

Often combined with:
- opioids
- ketamine
- alfaxalone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe Alfaxalone

A

IV or IM induction agent

Combined with other drugs (e.g. opioids) for sedation/pre-med

Useful option instead of a-2 agonists

Minimal effects on cardiovascular system

Drawback is large volume (IM) in big animals (painful)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe opioids

A

Used to provide pre-emptive & preventive analgesia & synergism with sedatives

Mild sedation when given alone to ASA I-II but more profound with ASA III-V

Limited cardiovascular effects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the difference between opiates & opioids?

A

Opiates: Drugs derived directly from opium (e.g., morphine, codeine).

Opioids: Includes naturally occurring, semisynthetic & synthetic substances with morphine-like activity acting at opioid receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the main uses of opioid analgesics?

A

Management of acute trauma pain

Pain relief during surgical or diagnostic procedures.

Treatment of painful medical conditions.

Long-term analgesic therapy for chronic pain, such as cancer-related pain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Why are opioids referred to as narcotic analgesics?

A

They provide analgesia but can also induce sedation, euphoria, or sleep-like state (narcosis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are the legal requirements for Schedule 2 opioids in the UK?

A

Majority of opioids

Require prescription for requisition

Stored in a lockable cupboard meeting specific criteria.

Prescription/dispensing recorded in bound controlled drug register kept for 2 years.

Destruction of stock witnessed by authorised person or RCVS member unaffiliated with the practice.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the key characteristics of schedule 3 opioids?

A

Require requisition & storage in locked cupboard

Buprenorphine (only relevant schedule 3 opioid in VetMed) doesn’t require entry in controlled drug register

Butorphanol is not classified as a controlled drug in the UK.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are the advantages of single-dose vials over multi-dose vials for opioids?

A

Single-dose vials: Simplify record-keeping by being prescribed & dispensed to single patient

Multi-dose vials: More prone to discrepancies due to needle hub & syringe dead space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are the partial & full agonists of opioids?

A

Partial agonists: Drugs like buprenorphine that activate opioid receptors but with ceiling effect

Full agonists: Drugs like morphine or fentanyl that fully activate opioid receptors for maximum analgesic effect.

28
Q

What are the 3 main opioid receptor types & what do they regulate?

A

μ (Mu): Spinal & supraspinal analgesia, sedation, euphoria, miosis (dogs), respiratory depression, decreased GI motility

κ (Kappa): Spinal & supraspinal analgesia, mild sedation, dysphoria, diuresis, miosis

δ (Delta): Spinal & supraspinal analgesia, cardiovascular depression.

29
Q

Where are opioid receptors found & what do they mediate?

A

Found in the CNS, peripheral tissues (e.g., GI tract, joints after inflammation)

Mediate inhibition of pain

30
Q

Describe the species, route of admin, duration, receptors & side effects/considerations for the following opioid:
Morphine (CD2)

A

Species: horse, cat, dog

Route: IM (SC, slow IV)

Duration: 4h (dog), 6-8h (cat)

Receptors: full MOR agonist

Side effects/considerations:
- vomiting
- histamine release

31
Q

Describe the species, route of admin, duration, receptors & side effects/considerations for the following opioid:
Methadone (CD2)

A

Species: horse, dog, cat

Route: IM (SC, slow IV)

Duration: 4h

Receptors: full MOR agonist

Side effects/considerations: high dose

32
Q

Describe the species, route of admin, duration, receptors & side effects/considerations for the following opioid:
Pethidine (CD2)

A

Species: horse, dog, cat

Route: IM (SC cats)

Duration: 1-1.5h

Receptors: Full MOR agonist

Side effects/considerations: histamine release

33
Q

Describe the species, route of admin, duration, receptors & side effects/considerations for the following opioid:
Fentanyl (CD2)

A

Species: dog, cat

Route: IV (IM)

Duration: 0.3h

Receptors: full MOR agonist

Side effects/considerations: decreased heart & respiratory rate

34
Q

Describe the species, route of admin, duration, receptors & side effects/considerations for the following opioid:
Butorphanol

A

Species: Horse, dog, cat

Route: IM, IV (SC)

Duration: 1h

Receptors: KOR agonist & MOR antagonist

Side effects/considerations:
- limited analgesia
- good sedation

35
Q

Describe the species, route of admin, duration, receptors & side effects/considerations for the following opioid:
Buprenorphine (CD3)

A

Species: horse, dog, cat

Route: IM, IV (SC)

Duration: 6-8h

Receptors:
- partial MOR agonist
- KOR antagonist

Side effects/considerations: slow onset

36
Q

What other drugs can possibly be given before induction

A

Anticholinergics

Antihistamines

H2 receptor antagonists & gastroprotectants

Anti nausea/vomiting medication (maropitant) & NK1 antagonism

Lidocaine IV

Steroids or NSAIDs

Antibiotics

37
Q

How do we choose premed?

A

History, physical examination

ASA classification

Pain management

Breed and BCS

Age

Temperament

Current drugs being given

Drug availability in practice

38
Q

Fill in the ASA status table

A

just know like 1 example

39
Q

What premed would you use in ASA-I dogs & cats

A

Acepromazine or alpha-2 agonist + opioid

40
Q

What premed would you use in ASA-II dogs & cats

A

Combination depends on disease

Low dose ACP/a-2 agonist & opioid usually tolerated

Care with ACP in liver disease

Care with a-2 agonists in CVS disease (e.g. mitral valve disease), ACP may be better option

a-2 agonist may be of use in HCM (low dose)

41
Q

What premed would you use in ASA-III-V dogs & cats

A

Avoid a-2 agonists in compromised animals

Low doses of a-2 agonist may be useful if animal is very distressed

Opioid alone may be sufficient to sedate patient (e.g. methadone or butorphanol)

Ketamine & midazolam (IM or IV) in cats (not in hypertrophic cardiomyopathy)

Alfaxalone & opioid (but high volume of injectate)
- can add Benzodiazepines (e.g. Midazolam or Diazepam) too

42
Q

What premed would you use in fearful/aggressive patients

A

a-2 agonists alone often insufficient to sedate

a-2 + ketamine + opioid (+- acepromazine) combination IM

Care with handling, environment, equipment, route & pheromones

If possible dispense medication for admin at home
- Gabapentin & Trazodone
- Alprazolam or diazepam

43
Q

What are the steps in anaesthesia preparation?

A
  1. Consider signalment & take a history
  2. Include anaesthesia history
  3. Examine animal
  4. Consider additional diagnostics
  5. Decide on ASA category
  6. Discuss the risks with owner
  7. Gain informed consent
44
Q

What should you do prior to undertaking anaesthesia in small animals

A

Consider starvation period

Weigh the animal

Plan anaesthetic & analgesic

Prepare anaesthesia equipment

Prepare drugs and IV fluids

Start to complete anaesthetic record

45
Q

What should you do prior to undertaking anaesthesia in horses

A

Before horse GA – remove shoes, clean out feet, flush out mouth, groom

Weigh

Prepare theatre, consider animal position during GA

Place IV cannula

46
Q

What is the purpose of an IV catheter during GA/sedation?

A

intravenous (IV) catheter is patient’s lifeline while under effects of GA & sedation

IV access allows for direct administration & rapid uptake of anaesthetic, analgesic & emergency drugs as required perioperatively

47
Q

What cannula would you use in a rabbit vs horse vs dog

A

Short stay 22g cannula in auricular vein of rabbit
14g in jugular vein of horse
20g in cephalic of a dog

48
Q
A

Acepromazine & buprenorphine

Medetomidine & methadone

49
Q
A

Methadone

50
Q
A

Dexmedetomidine & methadone

Medetomidine & buprenorphine

51
Q
A

Administer methadone and antihistamine

Administer low dose acepromazine and methadone

52
Q
A

Acepromazine

53
Q
A

0.12ml medetomidine and 0.36ml methadone

54
Q

dog is 12kg

A

0.12ml dexmedetomidine and 0.8ml buprenorphine

55
Q
A

2.75ml ACP and 1.1ml butorphanol

56
Q

How long should you fast a rabbit for prior to an ovariohysterectomy?

A

Don’t fast it

57
Q

What is approximate death rate in healthy dogs following anaesthesia (e.g. CEPSAF study)?

PS this is quite an important figure to know - as owners may well ask about risk

A

1/600

58
Q

Routine pre-anaesthesic blood testing is warranted in which of the following patients?

A

In patients requiring preanaesthetic stabilisation

In geriatric patients

In patients undergoing invasive surgery, with a high risk of haemorrhage

59
Q

Which dog breed is prone to regurgitation during anaesthesia?

A

Brachycephalics

60
Q

Which dog breeds are prone to opioid induced dysphoria?

A

Alaskan breeds

Labrador retrievers

61
Q

Which dog breeds can suffer from a gene mutation leading to sensitivity of some anaesthetic drugs and ivermectin?

A

Collies

62
Q

Which opioid is a full mu opioid receptor agonist (MOR), NMDA receptor antagonist, and affects noradrenaline re-uptake and is an excellent analgesic?

A

Methadone

63
Q

If a collie had a MDR1 gene mutation, which anaesthetic drug would they be sensitive to?

A

Acepromazine

64
Q

Which sedation/premedication drugs are available as oral gels for horses?

A

Acepromazine & Detomidine

65
Q

Which drugs could be used to antagonise a methadone overdose?

A

Butorphanol

Naloxone

66
Q

Moth is a 4 y/o siamese recently diagnosed with hyperthyroidism. Moth does not travel well, and is very fearful in the consult room. The owners have started oral medication for moth, but Moth needs monthly blood tests. Suggest drugs the owners can give orally to moth before she travels.

A

Gabapentin & Trazodone

67
Q

Kai is an uncooperative XL Bully of approx 50kg with a bite history that requires sedation prior to anaesthesia for removal of a grass seed that he has inhaled as he has a sudden onset sneezing of blood tinged fluid. The dog is muzzled and the owner can restrain him for a short period of time for an IM injection. What would you like to inject the dog with?

A

Dexmedetomidine, ketamine, butorphanol and acepromazine

LEAH FCP (49 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions