Pharmacology (specific drugs)

Question 1

Pharmacology of Adrenaline

Answer 1

A naturally occurring alpha and beta-adrenergic stimulant
Actions:
- Increases HR by increasing SA node firing rate (B1)
- Increases conduction velocity through A-V node (B1)
- Increases myocardial contractility (B1)
- Increases the irritability of the ventricles (B1)
- Causes bronchodilator (B2)
- Causes peripheral vasoconstricion (A)

Question 2

Pharmacology of Aspirin

Answer 2

An analgesic, antipyretic, anti-inflammatory and anti platelet 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

Pharmacology of Ceftriaxone

Answer 3

Cephalosporin antibiotic

Question 4

Pharmacology of Fentanyl

Answer 4

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

Question 5

Pharmacology of GTN

Answer 5

Principally, a vascular smooth muscle cell relaxant
Actions:
-Venous dilatation promotes velour pooling and reduces Venus 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 O2 demand
-Reduced systolic, diastolic and MAP, whilst 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 BP
-Preterm labour: Uterine quiescence in pregnancy

Question 6

Pharmacology of Ipratropium Bromide

Answer 6

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

Question 7

Pharmacology of Ketamine

Answer 7

A rapid acting dissociative anaesthetic agent (primarily an NMDA reception antagonist)
Actions:
Produces a dissociative state characterised by:
-A trance-like state with eyes open but not responsive
-Nystagmus
-Profound analgesia
-Normal pharyngeal and laryngeal reflexes
-Normal or slightly enhanced skeletal muscle tone
-Occasionally a transient and minimal respiratory depression

Question 8

Pharmacology of Methoxyflurane

Answer 8

Inhalational analgesic agent at low concentrations

Question 9

Pharmacology of Midazolam

Answer 9

Short acting CNS depressant
Actions: 
-Anxiolytic
-Sedative
- Anticonvulsant

Question 10

Pharmacology of Misoprostol

Answer 10

A synthetic prostaglandin
Actions:
-Enhances uterine contractions

Question 11

Pharmacology of Morphine

Answer 11

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