Active Ingredient: Remifentanil
For this indication, competent medicine agencies globally authorize below treatments:
For:
Regimen A: Intravenous, 1 micrograms remifentanil per kilogram of body weight, one dose. Afterwards, intravenous, between 0.5 micrograms remifentanil per kilogram of body weight and 1 micrograms remifentanil per kilogram of body weight, one dose.
Regimen B: Intravenous, between 0.5 micrograms remifentanil and 1 micrograms remifentanil, once every minute. Afterwards, intravenous, between 0.25 micrograms remifentanil and 0.4 micrograms remifentanil, once every minute.
The following table summarises the starting injection/infusion rates and dose range:
Dosing guidelines for adults:
| INDICATION | BOLUS INJECTION (micrograms/kg) | CONTINUOUS INFUSION (micrograms/kg/min) | |
|---|---|---|---|
| Starting Rate | Range | ||
| Induction of anaesthesia | 1 (give over not less than 30 seconds) | 0.5 to 1 | - |
| Maintenance of anaesthesia in ventilated patients | |||
| Nitrous oxide (66%)§ | 0.5 to 1 | 0.4 | 0.1 to 2 |
| Isoflurane (starting dose 0.5MAC)§ | 0.5 to 1 | 0.25 | 0.05 to 2 |
| Propofol (Starting dose 100 micrograms/kg/min)§ | 0.5 to 1 | 0.25 | 0.05 to 2 |
When given by slow bolus injection at induction remifentanil shall be administered over not less than 30 seconds.
At the doses recommended above, remifentanil significantly reduces the amount of hypnotic agent required to maintain anaesthesia. Therefore, isoflurane and propofol should be administered as recommended above and below to avoid an increase of haemodynamic effects such as hypotension and bradycardia (see Concomitant medication).
No data are available for dosage recommendations for simultaneous use of other hypnotics other than those listed in the table with remifentanil.
Remifentanil should be administered with a reduced dose of hypnotic agent, such as propofol, thiopentone, or isoflurane, for the induction of anaesthesia. ω can be administered at an infusion rate of 0.5 to 1 micrograms/kg/min, with or without an initial slow bolus injection of 1 micrograms/kg given over not less than 30 seconds. If endotracheal intubation is to occur more than 8 to 10 minutes after the start of the infusion of remifentanil, then a bolus injection is not necessary.
After endotracheal intubation, the infusion rate of remifentanil should be decreased, according to anaesthetic technique, as indicated in the above table. Due to the fast onset and short duration of action of remifentanil, the rate of administration during anaesthesia can be titrated upward in 25% to 100% increments or downward in 25% to 50% decrements, every 2 to 5 minutes to attain the desired level of mu-opioid response. In response to light anaesthesia, supplemental slow bolus injections, over not less than 30 seconds may be administered every 2 to 5 minutes.
Remifentanil decreases the amounts or doses of inhaled anaesthetics, hypnotics and benzodiazepines required for anaesthesia. Doses of the following agents used in anaesthesia: isoflurane, thiopentone, propofol and temazepam have been reduced by up to 75% when used concurrently with remifentanil.
Due to the very rapid offset of action of remifentanil no residual opioid activity will be present within 5 to 10 minutes after discontinuation. For those patients undergoing surgical procedures where post-operative pain is anticipated, analgesics should be administered prior to discontinuation of remifentanil. Sufficient time must be allowed to reach the maximum effect of the longer acting analgesic. The choice of analgesic should be appropriate for the patient’s surgical procedure and the level of post-operative care.
For:
Regimen A: Intravenous, 1 micrograms remifentanil per kilogram of body weight, one dose. Afterwards, intravenous, between 0.05 micrograms remifentanil per kilogram of body weight and 1.3 micrograms remifentanil per kilogram of body weight, once every minute.
Regimen B: Intravenous, 0.25 micrograms remifentanil per kilogram of body weight, once every minute. Afterwards, intravenous, between 0.05 micrograms remifentanil per kilogram of body weight and 1.3 micrograms remifentanil per kilogram of body weight, once every minute.
Co-administration of remifentanil and an intravenous anaesthetic agent for induction of anaesthesia has not been studied in detail and is therefore not recommended.
The following doses of remifentanil are recommended for maintenance of anaesthesia:
Dosing guidelines for maintenance of anaesthesia in paediatric patients (1 to 12 years of age):
| CONCOMITANT ANAESTHETIC AGENT* | BOLUS INJECTION (micrograms/kg) | CONTINUOUS INFUSION (micrograms/kg/min) | |
|---|---|---|---|
| Starting Rate | Range | ||
| Halothane (starting dose 0.3MAC)§ | 1 | 0.25 | 0.05 to 1.3 |
| Sevoflurane (starting dose 0.3MAC)§ | 1 | 0.25 | 0.05 to 0.9 |
| Isoflurane (starting dose 0.5MAC)§ | 1 | 0.25 | 0.06 to 0.9 |
* co-administered with nitrous oxide/oxygen in a ratio of 2:1
When given by bolus injection remifentanil should be administered over not less than 30 seconds. Surgery should not commence until at least 5 minutes after the start of the remifentanil infusion, if a simultaneous bolus dose has not been given. For sole administration of nitrous oxide (70%) with remifentanil, typical maintenance infusion rates should be between 0.4 and 3 micrograms/kg/min, and although not specifically studied, adult data suggest that 0.4 micrograms/kg/min is an appropriate starting rate. Paediatric patients should be monitored and the dose titrated to the depth of analgesia appropriate for the surgical procedure.
At the doses recommended above, remifentanil significantly reduces the amount of hypnotic agent required to maintain anaesthesia. Therefore, isoflurane, halothane and sevoflurane should be administered as recommended above to avoid an increase of haemodynamic effects such as hypotension and bradycardia. No data are available for dosage recommendations for simultaneous use of other hypnotics other than those listed in the table with remifentanil.
Due to the very rapid offset of action of remifentanil, no residual activity will be present within 5 to 10 minutes after discontinuation. For those patients undergoing surgical procedures where post-operative pain is anticipated, analgesics should be administered prior to discontinuation of remifentanil.
Sufficient time must be allowed to reach the therapeutic effect of the longer acting analgesic. The choice of agent(s), the dose and the time of administration should be planned in advance and individually tailored to be appropriate for the patient’s surgical procedure and the level of post-operative care anticipated.
For:
Regimen A: Intravenous, 0.5 micrograms remifentanil per kilogram of body weight, one dose, over the duration of 30 minutes.
Regimen B: Intravenous, between 0.25 micrograms remifentanil per kilogram of body weight and 0.5 micrograms remifentanil per kilogram of body weight, every minute.
The initial starting dose of remifentanil administered to patients over 65 should be half the recommended adult dose and then shall be titrated to individual patient need as an increased sensitivity to the pharmacological effects of remifentanil has been seen in this patient population. This dose adjustment applies to use in all phases of anaesthesia.
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