Opioid

Remifentanil

Ultra-short acting μ-agonist (ester linkage) · Ultiva

Mechanism: μ-opioid agonist; metabolized by non-specific plasma esterases.

Calculate dose for your patient

Enter weight (kg or lb). Always verify before administration.

Patient weight

Computed weight

70.0 kg · 154.3 lb

Infusion

3.5 mcg – 21 mcg

= 0.07–0.42 mL (50 mcg/mL)

mcg/kg/MIN. Always have longer-acting opioid on board.

Weight is saved on this device for the next calculator you open.

Full dose calculator

Onset

1–2 min

Duration

3–10 min regardless of infusion duration

Metabolism

Plasma & tissue esterases (organ-independent).

Dosing

Adult

Bolus 0.5–1 mcg/kg. Infusion: 0.05–0.5 mcg/kg/min (TIVA up to 1).

Pediatric

0.05–0.3 mcg/kg/min.

Indications

TIVA
Brief intense analgesia
Awake intubation

Contraindications

Epidural/intrathecal use (glycine vehicle)

Side Effects

Profound bradycardia/hypotension
Chest wall rigidity
Hyperalgesia after long infusion

Clinical Pearls

1Always have a longer-acting analgesic on board before stopping the infusion.

2Useful in obese, hepatic/renal failure — context-insensitive.

References & Further Reading

1
Textbook
Flood P, Rathmell JP, Shafer S. Stoelting's Pharmacology and Physiology in Anesthetic Practice. 5th ed. Philadelphia: Wolters Kluwer; 2015.
2
Textbook
Gropper MA, Miller RD, Cohen NH, et al., eds. Miller's Anesthesia. 9th ed. Philadelphia: Elsevier; 2020.
3
Textbook
Barash PG, Cullen BF, Stoelting RK, Cahalan MK, Stock MC, Ortega R, Sharar SR, Holt NF. Clinical Anesthesia. 8th ed. Philadelphia: Wolters Kluwer; 2017.
4
Textbook
Adriano A, Morris R, eds. 2021 CA-1 Tutorial Textbook (15th Ed.). Stanford University Medical Center, Department of Anesthesiology.

Citations are provided to direct further study. Always check the most current edition of guidelines and society recommendations — the information in this chapter is a teaching summary, not primary source material.