Ch. 21: Sedative Induction Agents

Question 1

Basics of Induction

Answer 1

Goal:

• Unconscious, Unresponsive and Amnestic
• Rapid
• Stable Cerebral Perfusion and Hemodynamics

BUT:

• All can cause myocardial depression and hypotension.
• In some cases so unstable that amnesia is safest goal.

Etomidate, Ketamine and Propofol are top agents

• Etomidate and Propofol act on GABA recepts
• Ketamine on NMDA receptor
• Lipophylic and work within 30 seconds

Obese patients:

• Risk hemodynamic compromise if actual weight used
• 1/3 (TBW - IBW) + IBW = kg used for dosing

Elderly:

• Use 1/2 to 2/3 of body weight for dose.

Question 2

Etomidate

Answer 2

0.3 mg/kg E equals 3 (0.2 if HD compromise)

Onset 15 to 45 seconds

Duration 3 to 12 minutes.

Relative HD stability.

Lowers Cerebral Blood Flow and metabolism.

Preserves CPP.

ADR: Pain. Inhibits cortisol and aldosterone.

Question 3

Ketamine

Answer 3

1.5 mg/kg

Onset 45 to 60 seconds

Duration 10-20 minutes

Stimulates catecholamines. Bronchodilates.

Best for those w bronchospasm or hypotension.

May not be good for hypertensive pt with CAD.

Good for awake intubation at titrated doses

May increase secretions so atropine 0.01mg/kg or glycopyrrolate 0.005 mg/kg given 15 min before awake intubation.

ADR: Emergence hallucinations.

Question 4

Propofol

Answer 4

1.5 mg/kg

Onset 15-45 seconds

Duration 5-10 minutes

Can lower BP by cardiac depression and vasodilation.

Lowers CPP. Bad in ICP pt

GOOD for stable patients and pregnant patients

ADR: Pain. Give 2cc of 1% lidocaine.

Can cause clonus.

Question 5

Versed

(Midazolam)

Answer 5

0.2 mg/kg

Onset 60-90 seconds. SLOW

Duration 15-30 min. Long

Best reserved for procedural sedation.

ADR: Hypotension and Pain on injection