Brainscape's Knowledge GenomeTM

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


See full index

Medical Specialties > Anaesthetics - pharmacology and principles > Flashcards

Anaesthetics - pharmacology and principles Flashcards

You may prefer our related Brainscape-certified flashcards:
USMLE® Step 1 flashcards
1
Q

What is the triad of anaesthesia?

A

Analgesia
Relaxation
Hypnosis

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

What is used for analgesia?

A

Local anaesthetics
Opiates
General anaesthetic agents

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

What is used for hypnosis?

A

General anaesthetic agents

Opiates

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

What is used for relaxation?

A

Muscle relaxants
Local anaesthetic
General anaesthetic agents

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

What are features of balanced anaesthesia?

A

Different drugs doing different jobs
Doses titrated seperately and more accurately
Avoid overdosage
Flexibility

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

What are problems of balanced anaesthesia?

A

Polypharmacy - drug interactions
Muscle relaxation - airway control required
Relaxation without hypnosis = awareness

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

How do general anaesthetic agents work?

A

Open chloride channels leading to hyperpolarised neurones which are less likely to fire

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

How are cerebral functions lost in general anaesthesia?

A

From top down
Most complex processes interrupted first - loss of conscious early
Reflexes spared

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

How must patients be managed during general anaesthesia?

A

Airway management - maintenance and protection
Impairment of resp function and control of breathing
Cardiovascular impact
Care of the unconscious patient

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

What are features of IV anaesthesia?

A

Rapid onset - 1 brain-arm circulation time

Rapid recovery - drug is removed from circulation

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

How is the drug from IV anaesthesia stored within the body?

A

Rapidly picked up by viscera, slowly picked up by fat and muscle and then slowly metabolised

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

What type of drugs are used as inhalational anaesthetics?

A

Halogenated hydrocarbons

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

How are inhalational anaesthetic drugs taken up by the body?

A

Goes along concentration gradient from lungs - blood - brain
Crosses alveolar membrane easily
Arterial concentration = close to alveolar pressure

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

What is Minimum Alveolar Concentration?

A

Concentration of drug required in alveoli to produce anaesthesia with a specific agent

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

What can be interpreted from the minimum alveolar concentration?

A

Measure of potency of anaesthetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are features of inhalation anaesthesia?

A

Slow induction
Very flexible in maintenance
For awakening - washout to reverse conc gradient to drive anaesthetic agent out

17
Q

What is the most common sequence of general anaesthesia?

A

IV induction followed by inhalation maintenance

18
Q

How does general anaesthetic affect the cardiovascular system?

A

Depress the CVS centre in the brain - reduce sympathetic outflow
Vasodilation
Venodilation

19
Q

How do general anaesthetics affect the respiratory system?

A

Respiratory depressant - reduce hypoxic and hypercarbic drive
Decreased tidal volume and increased rate
Paralysed cilia
Reduced lung volume and VQ mismatch - may be prolonged effect

20
Q

What are indications for muscle relaxants?

A

Ventilation and intubation
When immobility is essential
Body cavity surgery

21
Q

What are problems with muscle relaxants?

A

Awareness - no way to know if patient is still aware
Incomplete reversal can lead to airway obstruction and ventilatory insufficiency in immediate post op
Apnoea

22
Q

Why do we give intraoperative analgesia?

A

Prevent arousal from pain
Opiates contribute to hypnotic effect of GA
Suppression of reflex responses to pain

23
Q

What are features of regional anaesthetic agents?

A

Intense/complete analgesia

No direct hypnotic effects

24
Q

What are features of local anaesthesia and regional anaesthesia?

A

Patient retains awareness and consciousness
Lack of global effects of GA
Derangement of CVS physiology proportional to size of area affected
Sparing of resp function

25
Q

What is the main limiting factor in local anaesthetics?

A

Toxicity

26
Q

What causes toxicity of local anaesthetic agents?

A

High plasma levels - IV injection with absorption>metabolism

27
Q

How can we reduce toxicity?

A

Reduce absorption - vasoconstrictors reduce blood flow therefore reducing absorption

28
Q

What does toxicity depend on?

A

Dose used
Rate of absorption - site dependent
Patient weight
The drug used

29
Q

What are clinical features of local anaesthetic toxicity?

A 
Circumoral and lingual numbness and tingling
Light-headedness
Tinnitus/visual disturbances
Muscular twitching
Drowsiness
CVS depression
Convulsions
Coma
Cardiorespiratory arrest
30
Q

What is differential blockade in local anaesthetic?

A

Different nerve types take up different amounts of drug meaning some nerves are affected more than others

31
Q

What nerves take up the least local anaesthetic?

A

Motor

32
Q

Which nerves are easily blocked due to local anaesthetic?

A

Pain fibres

Medical Specialties (23 decks)

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