Remifentanil

Molecular formula C20H28N2O5 Molecular weight 376.45 CAS Registry No 132875-61-7 Merck Index 13,8216 

Sample preparation Mix 500 (xL whole blood with 10 (xL 50% citric acid and 25 (xL 500 ng/mL IS in 1 mM HCl, add 500 (xL 100 mM pH 7.4 phosphate buffer, vortex until homogeneous, add 2 mL dichloromethane, shake mechanically for 10 min, centrifiige at 13 000 rpm for 10 min. Evaporate the lower dichloromethane layer to dr5mess under a stream of nitrogen at room temperature, reconstitute the residue with 125 fiL mobile phase, inject a 20 (xL aliquot. 

Mobile phase MeCNichloroform 50 50 containing 2 mM ammonium acetate (Caution  

Detector MS, PE Sciex API-Ill Plus triple quadrupole, turbo ionspray, positive ion mode, turbo 200°, orifice 60 V, auxiliary gas nitrogen at 4 L/min, curtain gas at 1.2 L/min, m/z 

Bender, J. van den Elshout, J. SeUnger, K. Breeders, G. Bankers, J. vanderHeiden, C. Determination of remifentanil in human hepaiinised whole blood by tandem mass spectrometry with short-column separation, J.Pharm.BiomedJ ncd., 1999,21, 559 567. 

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Alfentanil, codein, dihydromorphine, etor-phine, fentanyl, heroin, hydromorphone, levo-methadone, morphine, oxycodone, pethidine, piritramide, remifentanil, sufentanil, tilidine, tramadol Buprenorphine, pentazocine Naloxone, naltrexone... 

Sufentanil, fentanyl, remifentanil, alfentanil, and morphine sulfate should be administered only by those specifically trained in the use of IV and epidural anesthetics Oxygen, resusdtative, and intubation equipment should be readily available. 

Remifentanil (Ultiva) is used for induction and maintenance of general anesthesia and for continued analgesia during the immediate postoperative period. This drug is used cautiously in patients witii a history of hypersensitivity to fentanyl. 

C4H(j02 96-33-3) see Aminoglutethimide Eprosartan Glutethimide Hexobendine Levocabastine Nialamide Phenglutarimide Pioglitazone Remifentanil Vincamine acrylonitrile... 

Mortazavi, S., Thompson, J., Baghdoyan, H. A. Lydic, R. (1999). Fentanyl and morphine, but not remifentanil, inhibit acetylcholine release in pontine regions modulating arousal. Anesthesiology 90, 1070-7. 

Remifentanil This is the exceptional drug in anaesthetic practice in that it is context insensitive. Draw a straight line starting from the origin and becoming near horizontal after the CSHT reaches 5 min. This demonstrates that the half time is not dependent on the length of infusion as clearance by plasma esterases is so rapid. 

Morphine Diamorphine Codeine Pethidine Fentanyl Alfentanil Remifentanil... 

Russia remains secretive about this operation. Reporters learned that they drilled holes in the floor and used vents high on the wall to pump gas into the theater. Regrettably, however, they were unable to learn the precise nature of the gas, beyond the admission by a Russian scientist that it was a derivative of Fentanyl. Several highly potent drugs fit that definition, including carfentanil, sufentanil, alfentanil, remifentanil and etorphine. Any of these can produce anesthesia, lasting from minutes to hours. A Russian medical authority later added that they used 5x the effective dose in order to guarantee a rapid effect on the terrorists. It is not clear exactly what this means. 

Diazepam is a prescription-only medicine whereas pethidine, morphine, alfentanil and remifentanil are controlled drugs. 

Fig. 7.19 Design of rapidly cleared ester analogues of sulfentanil propranolol and captopril. The compounds remifentanil, esmolol and FPL 66564 are all cleared to inactive metabolites.

In the case of remifentanil tv o sites of hydrolysis were incorporated into the molecule to provide sufficient metabolic lability [12, 13]. 

TIVA has become feasible thanks to the introduction of agents with a suitably short duration of action, including the injectable anesthetics propofol and etomidate, the analgesics alfentanil und remifentanil, and the muscle relaxant mivacurium. These drugs are eliminated within minutes after being adminster-ed, irrespective of the duration of anesthesia. 

In addition to the medicines mentioned above, a number of opiate- and non-opiate-based analgesics, including COX-2 inhibitors, anaesthetics (e.g. propofol, desflurane, sevoflurane, ropivacaine, levobupivacaine and remifentanil), neuromuscular blockers (e.g. rocuronium bromid, zemuron, cisatracuiium, doxacurium. 

PROPOXYPHENE (Dextropropoxyphene) Relief of mild to moderate pain. REMIFENTANIL HYDROCHLORIDE ... 

Administer continuous infusions of remifentanil only by an infusion device. The injection site should be close to the venous cannula. Clear all IV tubing at the time of discontinuation of infusion. 

General anesthesia - Remifentanil is not recommended as the sole agent in general anesthesia because loss of consciousness cannot be assured and because of a high incidence of apnea, muscle rigidity, and tachycardia. Remifentanil is synergistic with other anesthetics and doses of thiopental, propofol, isoflurane, and midazolam have been... 

Remifentanil Dosing Guidelines - General Anesthesia and Continuing as an Analgesic into the Postoperative Care Unit or... 

Children (1 year of age and older) - The table below summarizes the recommended doses in pediatric patients, predominantly American Society of Anesthesiologists (ASA) physical status I, II, or III. In pediatric patients, remifentanil was administered with nitrous oxide or nitrous oxide in combination with halothane, sevoflurane, or isoflurane. 

Induction of anesthesia - Administer at an infusion rate of 0.5 to 1 mcg/kg/min with a hypnotic or volatile agent for the induction of anesthesia. If endotracheal intubation is to occur less than 8 minutes after the start of infusion of remifentanil, then an initial dose of 1 mcg/kg may be administered over 30 to 60 seconds. 

Maintenance of anesthesia - After endotracheal intubation, decrease the infusion rate of remifentanil in accordance with the dosing guidelines in the table above. Because of the rapid onset and short duration of action of remifentanil, the rate of administration during anesthesia 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 p-opioid effect. In response to light anesthesia or transient episodes of intense surgical stress, supplemental bolus doses of 1 mcg/kg may be administered every 2 to 5 minutes. At infusion rates more than 1 mcg/kg/min, consider increases in the concomitant anesthetic agents to increase the depth of anesthesia. 

Continuation as an analgesic Into the immediate postoperative period -Remifentanil infusions may be continued into the immediate postoperative period for select patients for whom later transition to longer-acting analgesics may be desired. The use of bolus injections of remifentanil to treat pain during the postoperative period is not recommended. When used as an IV analgesic in the immediate... 

Elderly Decrease the starting doses of remifentanil by 50% in elderly patients (older than 65 years of age). Cautiously titrate to effect. 

Obesity Base the starting dose of remifentanil on ideal body weight (IBW) in obese patients (more than 30% over their IBW). 

Remifentanil For epidural or intrathecal administration hypersensitivity to fentanyl analogs. 

Do not use oxycodone in children. Safe dosage of codeine has not been established for children younger than 3 years of age. Safety and efficacy have been established with remifentanil from birth to 12 years of age in maintenance of general anesthesia. 

In obese patients (more than 20% above ideal body weight), determine the alfentanil, remifentanil, and sufentanil dosage on the basis of ideal body weight. Use fentanyl transmucosal with caution in patients with diabetes because it contains approximately 2 g of sugar per unit. 

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