Venous irritation, pain on injection and haemolysis associated with etomidate administration are attributable to its pharmaceutical vehicle, which is:
- A Soybean oil emulsion
- B Propylene glycol ✓
- C Cremophor EL
- D Absolute alcohol
Correct answer: B. Propylene glycol
Explanation
Etomidate is formulated in 35 percent propylene glycol, a hyperosmolar solvent responsible for pain on injection, thrombophlebitis and haemolysis. Propofol uses a soybean oil and egg phosphatide emulsion, which is why it is milky white and supports microbial growth. Cremophor EL was the vehicle of the withdrawn agent Althesin, notorious for anaphylaxis, and is not used in modern induction agents.
Reference: Morgan and Mikhail's Clinical Anesthesiology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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