Pharmacology

Question 1

Adrenaline

Answer 1

A naturally occurring alpha and beta-adrenergic stimulant
Actions:
- Increases HR by increasing SA node firing rate (Beta 1)
- Increases conduction velocity through the A-V node (Beta 1)
- Increases myocardial contractility (Beta 1)
- Increases the irritability of the ventricles (Beta 1)
- Causes bronchodilatation (Beta 2)
- Causes peripheral vasoconstriction (Alpha)

Question 2

Aspirin

Answer 2

An analgesic, antipyretic, anti-inflammatory and antiplatelet aggregation agent
Actions:
- To minimise platelet aggregation and thrombus formation in order to retard the
progression of coronary artery thrombosis in ACS
- Inhibits synthesis of prostaglandins - anti-inflammatory actions

Question 3

Dexamethasone

Answer 3

A corticosteroid secreted by the adrenal cortex
Actions:
- Relieves inflammatory reactions
- Provides immunosuppression

Question 4

Fentanyl

Answer 4

A synthetic opioid analgesic
Actions:
CNS effects:
- Depression – leading to analgesia
- Respiratory depression – leading to apnoea
- Dependence (addiction)
Cardiovascular effects:
- Decreases conduction velocity through the A-V node

Question 5

Glucagon

Answer 5

A hormone normally secreted by the pancreas
Actions:
– Causes an increase in blood glucose concentration by converting stored liver
glycogen to glucose

Question 6

GTN

Answer 6

Principally, a vascular smooth muscle relaxant
Actions:
- Venous dilatation promotes venous pooling and reduces venous return to the heart
(reduces preload)
- Arterial dilatation reduces systemic vascular resistance and arterial pressure
(reduces afterload)
The effects of the above are:
- Reduced myocardial O 2 demand
- Reduced systolic, diastolic and mean arterial blood pressure, whilst usually
maintaining coronary perfusion pressure
- Mild collateral coronary arterial dilatation may improve blood supply to ischaemic
areas of myocardium
- Mild tachycardia secondary to slight fall in blood pressure
- Preterm labour: Uterine quiescence in pregnancy

Question 7

Ipratropium Bromide

Answer 7

Anticholinergic bronchodilator
Actions:
- Allows bronchodilatation by inhibiting cholinergic bronchomotor tone (i.e. blocks vagal
reflexes which mediate bronchoconstriction)

Question 8

Methoxyf lurane

Answer 8

Inhalational analgesic agent at low concentrations

Question 9

Midazolam

Answer 9

Short acting CNS depressant
Actions:
- Anxiolytic
- Sedative
- Anti-convulsant

Question 10

Morphine

Answer 10

An opioid analgesic
Actions:
CNS effects:
- Depression (leading to analgesia)
- Respiratory depression
- Depression of cough reflex
- Stimulation (changes of mood, euphoria or dysphoria, vomiting, pin-point pupils)
- Dependence (addiction)
Cardiovascular effects:
- Vasodilatation
- Decreases conduction velocity through the A-V Node

Question 11

Naloxone

Answer 11

An opioid antagonist
Action:
- Prevents or reverses the effects of opioids

Question 12

Ondansetron

Answer 12

Anti-emetic
Action:
5HT 3 antagonist which blocks receptors both centrally and peripherally

Question 13

Paracetamol

Answer 13

An analgesic and antipyretic agent
Actions:
- Exact mechanism of action unclear; thought to inhibit prostaglandin synthesis in the
CNS

Question 14

Prochlorperazine (Stemetil)

Answer 14

An anti-emetic
Action:
- Acts on several central neuro-transmitter systems

Question 15

Salbutamol

Answer 15

A synthetic beta adrenergic stimulant with primarily beta 2 effects
Action:
- Causes bronchodilatation