remifentanil

CLINICAL USE

Analgesic Induction of anaesthesia

DOSE IN NORMAL RENAL FUNCTION

Induction: 0.5–1 microgram/kg/min Maintenance: Ventilated patients: 0.05–2 mcg/kg/min —Spontaneous respiration: 25–100 —nanograms/kg/minAnalgesia and sedation in ventilated, intensive care patients: 6–740 nanograms/kg/minuteAdditional analgesia during painful procedures in ventilated, intensive care patients: 100–750 nanograms/kg/minute

PHARMACOKINETICS

Molecular weight :412.9 (as hydrochloride)

%Protein binding :70

%Excreted unchanged in urine : 95 (as metabolites)

Volume of distribution (L/kg) :0.35

half-life – normal/ESRD (hrs) :3–10 minutes (biological activity)/unchangedTerminal elimination

10 to 20 : minutes

DOSE IN RENAL IMPAIRMENT

GFR (mL/MIN)

20 to 50 : Dose as in normal renal function

10 to 20 : Dose as in normal renal function

<10 : Dose as in normal renal function

DOSE IN PATIENTS UNDERGOING RENAL REPLACEMENT THERAPIES

CAPD :Unlikely to be dialysed. Dose as in normal renal function

HD :Not dialysed. Dose as in normal renal function

HDF/high flux :Unlikely to be dialysed. Dose as in normal renal function

CAV/VVHD :Unknown dialysability. Dose as in normal renal function

IMPORTANT DRUG INTERACTIONS

Potentially hazardous interactions with other drugs

Anti-arrhythmics: delayed absorption of mexiletine

Antidepressants: possible CNS excitation or depression (hypertension or hypotension) in patients also receiving MAOIs (including moclobemide) – avoid concomitant use; possibly increased sedative effects with tricyclics

Antipsychotics: enhanced sedative and hypotensive effect

Antivirals: concentration possibly increased by ritonavir (risk of toxicity) – avoidSodium oxybate: enhanced effect of sodium oxybate – avoid concomitant use

ADMINISTRATION

Reconstition

To 1 mg/mL with infusion fluid

Route

Rate of Administration

Dependent on indication

Comments

Dilute to 20–250 mcg/mL with glucose 5%, sodium chloride 0.9% or water for injection; usually 50 micrograms/mL for general anaesthesia

OTHER INFORMATION

Half-life of metabolite is increased to 30 hours in renal failure compared with 90 minutes in patients with normal renal functionMetabolite is essentially inactive Remifentanil would be expected to be metabolised before patient needs to be dialysed25–35% of metabolites are removed by dialysis.

See how to identify renal failure stages according to GFR calculation

See how to diagnose irreversible renal disease

Home