Remifentanil

Q: Remifentanil is metabolized by? (select one)

A) Kidney

B) Liver

C) Plasma

D) Auto-degraded

Answer: C

Remifentanil is metabolized by plasma esterases to inactive metabolites. This describes its ultrashort duration of action. It has a rapid onset of action, within three minutes. As it is metabolized in the plasma, it does not accumulate in the body. Despite its remarkable properties it failed to find its place in ICU. It failed to show any advantage in comparison to fentanyl or hydromorphone to decrease delirium, days of mechanical ventilation, or ICU length of stay. Also, it quickly develops tachyphylaxis. It is expensive and causes rebound hyperalgesia.

#pharmacology

#pain-management

References:

1. Tan JA, Ho KM. Use of remifentanil as a sedative agent in critically ill adult patients: a meta-analysis. Anaesthesia 2009; 64:1342. 

2. Joly V, Richebe P, Guignard B, et al. Remifentanil-induced postoperative hyperalgesia and its prevention with small-dose ketamine. Anesthesiology 2005; 103:147. 

3. Guignard B, Bossard AE, Coste C, et al. Acute opioid tolerance: intraoperative remifentanil increases postoperative pain and morphine requirement. Anesthesiology 2000; 93:409.