Sedation - meds and airway management

Question 1

Explain the difference between sedation and paralysis

Answer 1

Sedation: a temporary depression of consciousness to reduce responsiveness to the environment.

Paralysis: Renders the muscles unable to move ‘neuromuscular blocking agents’

Question 2

Describe Delayed Sequence Intubation (DSI)

Answer 2

Essentially procedural sedation for pre-oxygenation.

Useful for patients fighting pre-oxygenation and decreasing concentration on intubation preparation (ETOH/hypoxic/drugs etc)

DSI:
Ketamine 1mg/kg
–>
Preoxygenate 2-3 minutes
–>
Administer paralytic, wait 1 minute
–>
Intubate

Question 3

Describe Rapid Sequence Intubation (RSI)

Answer 3

Airway management technique that produces inducing immediate unresponsiveness (induction agent) and muscular relaxation (neuromuscular blocking agent) and is the fastest/most effective means of controlling the emergency airway.

Nine steps:

• Plan/prepare (airway equiptment, monitoring, meds, team, pt, PPE, ETT)
• Protect the cspine (if required)
• Pre oxygenate (100% hi flow O2 for 3 mins, can use nasal canula at 15L/min)
• Positioning (can use pillow under neck) - Pre treatment (prep aramine etc)
• Cricoid pressure (optional)
• Paralysis with induction (depolarising eg sux, or polarising eg roc)
• Placement with proof
• Post intubation management (cuff pressure, secure ETT, ongoing sedation, ventilation)

Question 4

Typical male and female ETT size

Answer 4

Female: 7-7.5mm

Male: 7.5-8.5mm

Question 5

Induction agents for sedation

Answer 5

• Fentanyl
• Ketamine
• Midazolam
• Propofol
• Thiopental

Question 6

Induction agents for sedation

Answer 6

• Fentanyl
• Ketamine
• Midazolam
• Propofol
• Thiopental

Question 7

Paralytic agent

Answer 7

• Rocuronium (non-depolarising)
• Pancuronium (non-depolarising)
• Cistacurium besylate (non-depolarising)
• Suxamethonium (depolarising)
• Vecuronium

Question 8

Fentanyl - indication, dose, onset time, duration, side effect, contraindication

Answer 8

Indication:
Opioid analgesic. Short acting, conscious sedation. Induction dose: 50-100mcg

Onset time:
<60seconds Duration: Dose dependent (30 min for 1-2mcg/kg, 6 hours for 100mcg/kg)

Side effect:
Resp depression, apnoea, circulatory depression, myoclonic jerks, bronchospasm

Contraindication:
Obstructive lung disease, severe resp depression, opioid hypersensitivity, raised ICP

Question 9

Ketamine - indication, dose, onset time, duration, side effect, contraindication

Answer 9

Indication:
Non-barbituate rapid acting general anaesthetic.
RSI, especially if heamodynamically unstable.
Good for TBI as does not raise ICP.
Good for reactive airway disease as causes bronchodialation.

Induction dose:
2mg/kg Onset time: 30 seconds

Side effects:
Emergence syndrome, increased myocardial oxygen consumption, increased secretions

Contraindication:
Condition that a significant raise in BP would be hazardous

Question 10

Ketamine - indication, dose, onset time, duration, side effect, contraindication

Answer 10

Indication:
Non-barbituate rapid acting general anaesthetic.
RSI, especially if heamodynamically unstable.
Good for TBI as does not raise ICP.
Good for reactive airway disease as causes bronchodialation.

Induction dose:
2mg/kg

Onset time:
30 seconds

Side effects:
Emergence syndrome, increased myocardial oxygen consumption, increased secretions

Contraindication:
Condition that a significant raise in BP would be hazardous

Question 11

Midazolam - indication, dose, onset time, duration, side effect, contraindication

Answer 11

Indication:
Short acting benzodiazepine - used for conscious sedation.
Not recommended for RSI but can be used for RSI of shocked patients.

Conscious sedation dose:
1-2.5mg over 2 min
Induction dose:
0.02mg/kg (10-15mg)

Onset time:
15-30 minutes

Side effects:
Respiratory depression, apnoea, hypotension, paradoxical agitation

Contraindication:
Myasthenia Gravis

Question 12

Propofol - indication, dose, onset time, duration, side effect, contraindication

Answer 12

Indication:
Short acting general anaesthetic.
Induction of anaesthesia/sedation
First line sedation for RSI.
Useful for pt’s with reactive airway disease and status epilepticus.

Induction dose:
2-2.5mg/kg
Maintenance dose:
1-3mg/kg/hr

Onset time: 15-45 seconds

Duration: 5 - 10 minutes

Side effects:
Hypotension and bradycardia. Myocardial depression, reduced cerebral perfusion

Contraindication: Egg allergy. Children <16. Heamodynamically unstable

Question 13

Propofol - indication, dose, onset time, duration, side effect, contraindication

Answer 13

Indication:
Short acting general anaesthetic.
Induction of anaesthesia/sedation
First line sedation for RSI.
Useful for pt’s with reactive airway disease and status epilepticus.

Induction dose:
2-2.5mg/kg
Maintenance dose:
1-3mg/kg/hr

Onset time:
15-45 seconds

Duration:
5 - 10 minutes

Side effects: Hypotension and bradycardia. Myocardial depression, reduced cerebral perfusion

Contraindication: Egg allergy. Children <16. Heamodynamically unstable

Question 14

Thiopental - indication, dose, onset time, duration, side effect, contraindication

Answer 14

Indication:
Barbituate, general anaesthetic.
Used for RSI.

Induction dose:
3-5mg/kg

Duration:
5-10 minutes

Side effects:
Laryngospasm, hypotension, hypokalaemia, vasodilation

Contraindications:
Heamodynamically unstable. Status asthmaticus.

Question 15

Thiopental - indication, dose, onset time, duration, side effect, contraindication

Answer 15

Indication:
Barbituate, general anaesthetic.
Used for RSI.

Induction dose:
3-5mg/kg

Duration:
5-10 minutes

Side effects:
Laryngospasm, hypotension, hypokalaemia, vasodilation

Contraindications:
Heamodynamically unstable. Status asthmaticus.

Question 16

Define a depolarizing neuromuscular blocker

Answer 16

eg: rocuronium

Acts as acetylcholine (ACh) (neurotransmitter) receptor antagonists by binding to the ACh receptor and stopping any action potentials. This stops the transmission of sodium and therefore conduction of the nervous system, causing relaxation.

Question 17

Suxamethonium - indication, dose, onset time, duration, side effect, contraindication

Answer 17

Indication:
Short acting depolarizing neuromuscular blocker.
Facilitated ETT intubation.

Dose: 0.6-1.1mg/kg

Onset time:
30-60 seconds

Duration:
6-10 minutes

Side effects:
Hyperkalaemia, malignant hyperthermia, increased intraocular pressure

Contraindications:
Major burns, crush and spinal injuries, hyperkalaemia, open eye injury, hx of malignant hyperthermia

Question 18

Suxamethonium - indication, dose, onset time, duration, side effect, contraindication

Answer 18

Indication:
Short acting depolarizing neuromuscular blocker.
Facilitated ETT intubation.

Dose:
0.6-1.1mg/kg

Onset time:
30-60 seconds

Duration:
6-10 minutes

Side effects:
Hyperkalaemia, malignant hyperthermia, increased intraocular pressure

Contraindications:
Major burns, crush and spinal injuries, hyperkalaemia, open eye injury, hx of malignant hyperthermia

Question 19

Rocuronium - indication, dose, onset time, duration, side effect, contraindication

Answer 19

Indication:
Non-depolarising neuromuscular blocker.
Facilitate ETT intubation.
Provide muscle relaxation during mechanical ventilation.
Can be used for RSI unless rapid recovery is required - eg elective surgery or neuro assessment

Induction dose:
0.6mg/kg

RSI dose:
1-2mg/kg

Onset time:
60-90 seconds

Duration:
30-40 minutes

Side effects:
Allergy - rare