DRUGS

Question 1

Vasopressors

Answer 1

• peripheral noradrenaline, 6mg in 100ml 0.9% N/S - 2-20mcg/min titrate to MAP >60
• metaraminol 10mg in 20ml 0.9%

Question 2

Induction Agents

Answer 2

Premedication with fentanyl 2-3mcg/kg IV
- good for raised ICP, cardiac ischemia and aortic dissection
- blunts sympathetic effect of laryngeal manipulation
Causes respiratory depression and hypotension

Sedation:

Propofol 1-2mg/kg

Benefits:
- quick onset 20-40sec
- quick offsent 8-12min
- anti-emetic properties
- anti-convulsant properties

Disadvantages:
- reduce ICP
- respiratory depression/apnoea
- myocardial depression and vasodilation causeing hypotension
- no analgesic properties
- can’t use in patients with soybean and egg allergy

Ketamine 1-2mg/kg

Benefits:
- preserves respiratory drive
- analgesic properties
- cardiovascular stability
- bronchodilator
- dissociative amnesia
- possible cerebroprotective effects
Disadvantages:
- increased secretions
- hypertension, tachycardia
- emergence phenomena

Rocuronium 1.2mg/kg
- longer onset (1-2min)
- longer duration of action (30-45min)
- tachycardia
- reversal with sugammadex 2-4mg/kg iv

Suxamethonium 1.5mg/kg (IM dose 4mg/kg)
- quick onset 30-60sec
- quick offset 5min

contraindications for sux:
- pre-existing hyperkalemia
- burns >5days old
- denervation injury >5 days old
- significant crush injuries >5days old
- pre-existing myopathies - muscular dystrophe

Complications for sux:
- fasciculations
- transient intracranial, intraocular, intracranial pressure
- bradycardia
- masseter spam
- malignant hypertension -> dantroline 2.5mg/kg + cooling measures
- prolonged apnoea with pseudocholinesterase deficiency or myasthenia gravis