Brainscape's Knowledge GenomeTM

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


See full index

Anaesthesia > Pharmacology of Injectable Drugs > Flashcards

Pharmacology of Injectable Drugs Flashcards

1
Q

What are the advantages of injectable anaesthesia?

A
  • Little equipment needed (syringes, needles, IV catheters)
  • Usually, easy to administer
  • Induction of anaesthesia can be rapid & smooth
  • Possibly relatively cheap
  • Limited environmental pollution (inhalants –> Greenhouse effect; plastics)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the disadvantages of injectable anaesthesia?

A
  • Once given, retrieval is impossible
  • The P must be weighed accurately to calculate the dose, esp in the smaller animals!
  • Dose readjustment in sick/debilitated animals
  • Some drugs have the potential for human abuse
  • Risks of inadvertent self-administration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

All drugs have the potential to cause…

A

apnoea, so be prepared for immediate intubation

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

propofol is what type of injectable anaesthetic?

A

non-barbiturate

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

What is the MoA of Propofol?

A
  • GABA(alpha) receptor (beta subunit) –> slows down closure, activates directly
  • indirectly potentiates activation of the channels
  • direct in high amounts, will directly activate GABA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Propofol solubility

A

Insoluble in water
highly lipid solube

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

Propofol formulation contains…

A

10% soybean oil
2.25% glycerol
3.1.2% purified egg phosphatide

Great media for bacterial growth

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

If no preservatives are present in Propofol, how long is the vial good for?

A

24 hrs

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

Propoflo 28/PropoVet multidose uses what as a preservative?

A

benzyl alcohol, which can accumulate & be toxic

Do not use for TIVA

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

What is the propofol onset of action?

A

60-90 sec or faster

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

What is the duration of action of Propofol?

A

About 10-15 min of anaesthesia

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

Propofol is suitable for…

A

inductions & maintenance as CRI (preservative-free only)

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

Protein binding of propofol?

A
  • Free fraction in plasma only 1.2-1.7%
  • Binds to albumin/erythrocytes
  • Low RBCs impacts dosage
  • Free fraction in CSF 31%
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Elimination of Propofol?

A

Exceeds hepatic blood flow
Extra-hepatic metabolisation sites –> kidneys, SI, lungs?
Metabolite: glucuronidation into non-active metabolites

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

Propofol has dose-dependent CV depression which causes what signs?

A
  • vasodilation
  • negative inotropic
  • reduction of CO
  • compensatory increase in HR abolished
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Dose & rate dependent respiratory depression caused by Propofol causes what signs?

A

hypoventilation
apnoea

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

Propofol does not have

A

analgesic properties

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

What are the neuroprotective effects of Propofol?

A
  • decreases ICP
  • reduces cerebral metabolic rate (CMRO2)
  • may reduce cerebral perfusion pressure in P’s w/ high ICP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is unique about propofol usage in cats?

A
  • prolonged recoveries after repetitive boluses or long infusions
  • feline hgb prone to oxidative injury by phenolic compounds which decrease PCV –> Heinz body anaemia if given several boluses over multiple days
  • TIVA - difficult recovery
  • Repeated or prolonged propofol anaesthesia leads to: anorexia, depression, D, facial oedema, delayed recovery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are clinical uses of propofol?

A
  • C-sections
  • renal p’s
  • hepatic p’s
  • TIVA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the contraindications of Propofol?

A
  • hypovolaemia/shock
  • heart failure
  • diabetic hyperlipidaemia/pancreatitis?
  • avoid repeated propofol/>30 min TIVA in cats
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the main uses of Propofol?

A
  • Sedation in SA
  • induction of anaesthesia
  • balanced anaesthesia
  • maintenance (TIVA/PIVA)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Alfaxalone is what kind of anesthetic?

A

steroid

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

Alfaxalone is licensed in what species?

A

dogs, cats, rabits, other wildlife

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

What route of admin is used with alfaxalone?

A

SQ, IM, IV

26
Q

Alfaxalone solubility

A

insoluble in water

27
Q

Alfaxan formulation does not have what side effects that were present in Saffan?

A
  • no histamine release
  • no perivascular necrosis
28
Q

What is the mechanism of action of alfaxalone?

A
  • increases Cl- conduction of cell –> inhibitory efect
  • Works on Gaba(alpha)
29
Q

What are the physico-chemical properties?

A
  • colourless sln
  • commercial prep 10 mg/ml
  • does not irritate tissues
  • does not promote bacterial growth
  • 28-day shelf life in multidose formulation
30
Q

Onset of action of Alfaxalone?

A

30-60 sec

31
Q

Duration of action of Alfaxalone?

A

10 mins

32
Q

Metabolism & excretion of Alfaxalone?

A

Phase I of liver via cytochrome p450

33
Q

What are the effects of Alfaxalone?

A
  • rapid loss of consciousness
  • smooth induction
  • good muscle relaxation
  • duration of effect depending on dose/redosing
  • resp depression/apnoea (dose/rate dependent)
  • hypotension
  • myoclonus & opisthotonus possible in recovery
34
Q

Alfaxalone is suitable for use as CRI in…

A

CATS

35
Q

What are the indications and clinical use of Alfaxalone?

A
  • induction in small animal/rabbits/reptiles/birds
  • slow titration to effect
  • no analgesic effects
  • use in C-sections
  • TIVA
36
Q

What are the main dissociatives used for injectable anaesthesia?

A

Ketamine, Tiletamine (+ Zolazepam), Thiopental, Etomidate

37
Q

What are the main features of dissociatives?

A
  • dissociation btw thalamic & limbic system
  • fxnl disorganisation of CNS
  • analgesia, amnesia
  • maintained reflexes
  • catalepsy –> muscular rigidity
38
Q

What is the MoA of Ketamine?

A
  • NMDA antagonism
  • Binds: opioid, cholinergic, adrengergic, GABA(A) receptors; Na+ channels
39
Q

What are the physico-chemical properties of Ketamine

A

White crystalline powder
slns: 1, 5, 10%
preservative: benzethonium chloride
pH: 3.5-5.5 (pain on inj IM, esp in cats)
stable sln, protect from light/heat

40
Q

What are the routes of admin of Ketamine

A

IV, IM, SQ, IP, transmucosal, epidural

41
Q

What are the pharmacokinetics of ketamine?

A
  • rapid distribution
  • protein binding 50-60%
  • rapid cross BBB (highly lipophilic)
42
Q

What is the metabolism & excretion of ketamine?

A

Liver metabolism: ketamine (Active metabolite) –> norketamine (Active) –> inactive glucuronide metabolites –> excreted via kidney

42
Q

What is unique about ketamine in cats and kidney dz?

A
  • excrete some metabolite, metabolisation can stop at norketamine
  • problems w/ kidneys –> prolonged duration of action = longer recovery
43
Q

What are the CV effects of ketamine?

A
  • reduced inotropism - direct effect on heart; critically ill patients, hypotension
  • sympathetic stimulation: increased HR/MAP/CO/O2 consumption, if depleted of catecholamines, there is limited sympathetic stimulation
43
Q

What are the CNS effects of ketamine

A
  • does not appear to be asleep
  • no response fom esternal stimuli
  • increase in ICP (vasodilation & increase in BP)
  • increase in CMRO
  • Seizures?
44
Q

What are the main resp system effects of ketamiine?

A
  • minimal resp depression: maintains response to hypoxia & CO2, apneustic breathing pattern, transient apnoea if IV fast
  • potentiates resp depression of other CNS depressants
  • bronchial smooth muscle relaxation: bronchodilation, decreased airway resistance, clinical uses
  • pharyngeal/laryngeal reflexes maintained: uncoordinated,** not protective, caution in upper airway exams/upper airway obstruction**
45
Q

What are other effects of ketamine?

A
  • pain at IM inj
  • poor muscle relaxation
  • central eye, increases IOP
  • analgesia/anti-hyperalgesia
46
Q

What are clinical uses & indications of ketamine?

A
  • anaesthesia induction in every species; key in horse & wild/exotics
  • peri-op analgesia/anti-hyperalgesia/ balanced anaesthesia: CRI for analgesia
  • licensed in cattle
  • to achieve IV access by giving IM inj
47
Q

What are the contraindications of ketamine?

A
  • HCM
  • increased ICP
  • increased IOP
  • kidney dz in cats
48
Q

What is the mechanis of action of Telazol/Zoletil?

A
  • Zolazepam: Benzodiapine –> cannot remove tiletamine side effects (muscle rigidity/seizure-like manifestions), addition of alpha-2/opioids
  • analgesia
  • short shelf-life once reconstituted
49
Q

What are the effects of Telazol/Zoletil (Tiletamine + Zolazepam)?

A

Onset: 60-90 sec IV, 2-10 min IM
other effects similar to ketamine
rough recoveries if redosing occurs in dogs/horses

50
Q

Indications & clinical use of Tiletamine + Zolazepam

A

Induction of anaesthesia
Transport (wild/exotics)
Do NOT use in large felids

51
Q

High doses of tiletamine + zolazepam can be used in what species?

A

cats for surgical anaesthesia

52
Q

What is the mixture using Telazol for shelter medicine?

A

TTDex
Telazol
Torbugesic
Dexdomitor

53
Q

Contraindications of Tiletamine + Zolazepam

A
  • avoid in patients w/ head trauma/intracranial tumours
  • avoid in intraocular globe procedures/open globe
  • HCM
54
Q

Thiopental is not

A

used anymore

55
Q

Main effects of thiopental

A
  • Rapid loss of consciousness
  • Single bolus: 5-10 min anaesthesia
  • Anti-epileptic, reduced ICP
  • Marked resp depression
  • Hypotension, reduced CO, vasodilation, arrhythmias
  • Perivascular inj: tissue necrosis
  • STRICTLY IV INJECTION
  • High pH, can cause extreme perivascular necrosis
56
Q

Thiopental uses

A
  • Induction in CV stable patients
  • Fast endotracheal intubation
  • “lar-par” exam
  • Patients w/ increased ICP
  • Seizures
  • Bolus when horse is “superficial”
  • Induction in horses
57
Q

What are the uses of etomidate?

A
  • Cardiac dz (ex. DCM)
  • CV unstable patients
  • Neurologic patients (seizures, increased ICP)
58
Q

What are the main characteristics of etomidate?

A
  • CV stability
  • minimal resp depression
  • myoclonus, dystonia, tremor
  • neuroprotective - decreases cerebral metabolic rate & ICP
  • NOT an analgesic
  • Adrenocortical suppression

Anaesthesia (24 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions