Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027497 (nausea)
 23,468 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Remifentanil is a novel, short-acting mu-receptor opioid agonist currently in the late stages of development. A member of the 4-anilidopiperidine class, it is unique among the currently marketed agents because of its ester structure. Remifentanil undergoes widespread extrahepatic metabolism by blood and tissue nonspecific esterases, resulting in an extremely rapid clearance of approximately 3 L/min (180 L/h). Like the other members of this class of drugs, remifentanil is lipophilic and is widely distributed in body tissues with a steady-state volume of distribution of approximately 30L. Because of its unique metabolic pathway (among this group of drugs) and rapid clearance, remifentanil represents a new pharmacokinetic class of opioid. Unlike the other fentanyl congeners, termination of the therapeutic effect of remifentanil mostly depends on metabolic clearance rather than on redistribution. The context-sensitive half-time [defined as the time necessary to achieve a 50% decrease in blood (or plasma) concentration after termination of a variable-length, continuous infusion targeted to maintain a steady-state concentration, where the 'context' is the duration of the infusion] is strikingly short for remifentanil, and this is perhaps the most compelling evidence of the pharmacokinetic singularity of the drug. Determined by computer simulation, the context-sensitive half-time of remifentanil is approximately 3 minutes, and is independent of infusion duration. Pharmacodynamically, remifentanil is similar to the other fentanyl congeners. The drug produces physiological changes consistent with potent mu-receptor agonist activity, including analgesia and sedation. Its adverse effect profile (like that of the other drugs of this class) includes ventilatory depression, nausea, vomiting, muscular rigidity, bradycardia and pruritus. Because it does not release histamine upon injection, remifentanil has fewer haemodynamic adverse effects than morphine. The therapeutic potency of remifentanil is somewhat less than that of fentanyl, with an effective concentration (producing 50% of maximal effect, as measured by electroencephalography) of approximately 15 to 20 micrograms/L. Speed of onset of effect is very rapid and is similar to that of alfentanil, which is reflected in a t1/2ke0 (a parameter used to characterise the delay between peak blood drug concentration and peak pharmacodynamic effect utilising a theoretical effect compartment) of approximately 1 to 2 minutes. Remifentanil is likely to be a welcome addition to the anaesthesia drug formulary. Anaesthetists have long recognised the need for a short-acting opioid with a predictable pharmacokinetic profile.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Remifentanil pharmacokinetics and pharmacodynamics. A preliminary appraisal. 758 3

We evaluated the use of an infusion of remifentanil to provide postoperative analgesia during recovery from total intravenous anesthesia (TIVA) with remifentanil and propofol. One hundred fifty-seven patients from seven medical centers underwent abdominal, spine, joint replacement, or thoracic surgery. Remifentanil was titrated in an effort to limit pain to 0 or 1 on a 0-3 scale. At the end of the 30-min titration period, 78% of infusion rates were in the range of 0.05 to < or = 0.15 microgram.kg-1.min-1, 5% were < 0.05 microgram.kg-1.min-1, and 17% were > 0.15 microgram.kg-1.min-1. Pain scores were 0 or 1 in 64% of patients. Nausea occurred in 35% and emesis in 8% of patients; the peak incidence of nausea followed discontinuation of the remifentanil infusion at the time of administering morphine. Respiratory adverse events (oxygen saturation by pulse oximetry [Spo2] < 90% or respiratory rate < 12) affected 29% of patients. Apnea occurred in 11 patients (7.0%). There was a large variation in the incidence of respiratory depression between the centers, ranging from 0 to 75%. The explanation for the large variability in respiratory outcome was not evident.
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PMID:A multicenter evaluation of remifentanil for early postoperative analgesia. 894 2

Remifentanil is an ultrashort acting mu opioid, well suited to total intravenous (i.v.) anaesthesia. Pain immediately following emergence from anaesthesia is a potential problem because of the rapid offset. This study investigated the transition from remifentanil/propofol total intravenous anaesthesia to post-operative analgesia with epidural or patient controlled analgesia morphine in 22 patients undergoing major abdominal surgery. A remifentanil post-operative infusion initiated during emergence was titrated in the recovery room for 30 min, at which time 14% of patients had a pain score of 2 and 86% had pain scores of 0 or 1 (0 = no pain; 1 = mild pain; 2 = moderate pain; 3 = severe pain), at a mean infusion rate of 0.086 microgram kg-1 min-1. A smooth transition was then made to either epidural analgesia or patient controlled analgesia with morphine; pain scores were not significantly changed during the transition. Nausea occurred in 16 of the 22 patients, but only following administration of morphine. Epidural analgesia produced significantly lower pain scores on the surgical ward compared with patient controlled analgesia.
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PMID:Transition to post-operative epidural or patient-controlled intravenous analgesia following total intravenous anaesthesia with remifentanil and propofol for abdominal surgery. 925 64

Otologic procedures require a still surgical field and are associated with a 50% incidence of emetic symptoms. Propofol reduces nausea and vomiting but not intraoperative movement. This study compares a remifentanil/propofol anesthetic to a propofol/fentanyl combination to determine which provides the best perioperative conditions for otologic microsurgery. Eighty healthy patients were randomly assigned to receive one of the anesthetic combinations. Demographic data, hemodynamic variables, movement, and bispectral index monitoring values in addition to anesthetic emergence, nausea, vomiting, pain, and other recovery variables were compared between groups with appropriate statistical methods. Both groups were similar. Times to eye opening (7.7 +/- 0.7 vs 12.4 +/- 1.2 minutes) and extubation (9.8 +/- 0.9 vs 12.4 +/- 1.0 minutes) were shorter with remifentanil. This group also had lower hemodynamic variables and movement (23% vs 65%) under anesthesia. Postoperative pain was mild in both groups, but remifentanil patients had more than the propofol group. All other postoperative parameters were similar. Remifentanil-based anesthesia produces better hemodynamic stability, less movement, and faster emergence after otologic surgery, with propofol's antiemetic effect, for the same cost.
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PMID:Remifentanil-based anesthesia versus a propofol technique for otologic surgical procedures. 1065 94

We performed a prospective, randomized study comparing the efficacy and safety of remifentanil, propofol or both for conscious sedation during eye surgery under retrobulbar blockade. Forty-five unpremedicated patients were assigned to receive remifentanil (group R) (n = 15, mean dosage: 0.05 +/- 0.03 microgram kg-1 min-1), propofol (group P) (n = 15, 1.5 +/- 0.5 mg kg-1 h-1) or a combination (group RP) (n = 15, R: 0.03 +/- 0.01 microgram kg-1 min-1; P: 0.7 +/- 0.2 mg kg-1 h-1). Haemodynamic responses were comparable among all groups. Minimum values for respiratory rate were lower in R patients (R: 7 vs. P and RP: 10 breaths min-1). Perioperative blood gas analysis showed differences in maximum carbon dioxide tensions (R: 51.5 vs. P: 48.3 vs. RP: 45.5 mmHg) and decrease in minimum pH values (R: -0.06 vs. P: -0.0 vs. RP: -0.01). All group P patients reported mild to intense pain during retrobulbar block, while 53% of the group R patients were free from pain. In group RP, 60% of patients experienced no pain and the remaining 40% reported mild pain only. Remifentanil, applied as the sole agent, provided superior pain relief and patient comfort when compared with propofol, but produced greater respiratory depression and postoperative nausea. The combination of remifentanil and propofol provided haemodynamic stability, adequate spontaneous respiration and pain relief, with a low risk of untoward side effects.
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PMID:Remifentanil, propofol or both for conscious sedation during eye surgery under regional anaesthesia. 1071 67

We compared Remifentanil, an esterase-metabolized opioid, with Alfentanil as part of the total intravenous anesthesia with propofol and atracurium for out-patient laparoscopic gynaecological procedures in a multicenter randomized, double-blind study. We chose Remifentanil 1 mg./kg.for bolus injection and a continuous infusion of 0.25-0.5 microg./kg./min, compared to Alfentanil 20 microg./kg. For bolus injection and a continuous infusion of 0.5-1 microg./kg./min. Fifty-nine patients received Remifentanil, and sixty-three received Alfentanil. Patients who received Remifetanil experienced significantly fewer stress responses to surgical stimuli (p < 0.05) and required fewer additional boluses of study drugs and propofol (p < 0.05) than Alfentanil during the intraoperative period. Response time to verbal commands, spontaneous respiration, adequate respiration and tracheal extubation, were not significantly different between these two opioids. Remifentanil patients, required more fentanyl for post operative pain control, 40 from 59 cases in the Remifentanil group and 22 from 63 cases in the Alfentanil group (p < 0.05) but still showed significantly better recovery of psychomotor function by Aldrete score of ten at 50 and 60 min (p < 0.05) than Alfentanil patients. The incidence of intraoperative bradycardia was significantly higher with Remifentanil. Other incidences of nausea, emesis, urinary retention and postural hypotension were similar. All patients were ready to be discharged from the hospital within two hours after extubation except for one patient in the Alfentanil group who needed five hours of hospital stay because of urinary retention, nausea and severe emesis.
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PMID:A multicenter randomized double-blind comparison of remifentanil and alfentanil during total intravenous anaesthesia for out-patient laparoscopic gynaecological procedures. 1121 62

We evaluated the use of remifentanil administered as a component of an inhalation or of a Target Controlled Infusion (TCI) anesthetic technique during outpatient oral surgery. Sixty-three unpremedicated patients undergoing removal of four impacted third molars participated to this prospective, randomized study. Anesthesia was induced with Propofol and Rocuronium. Remifentanil 1 microgram.kg-1 i.v. was given over 30 s followed by a continuous infusion reduced from 25% each time a tooth was removed (0.25-->0.0625 microgram.kg-1 min-1). Anesthesia was maintained with Desflurane (group D, n = 31) (end-tidal concentration 4-6%) or Propofol (group P, n = 32) (initial infusion TCI 8 micrograms.ml-1 reduced to 2-3 micrograms.ml-1 after intubation). Corticosteroids, a non-steroidal anti-inflammatory drug (NSAID) (Diclofenac) and a partial mu agonist drug (Tramadol) were administered i.v. during the procedure to prevent early postoperative pain. Recovery time, postoperative pain, recovery of cognition and nausea or vomiting were also evaluated during the first six postoperative hours. Overall mean systolic blood pressures and heart rate were similar in the two groups during surgery. Mean times to extubation and to recall of birth-date and room number were also similar. The quality of awakening was good in the two groups. Most patients complained of moderate pain or had no pain during the first six postoperative hours. The incidence of nausea and vomiting was similar in both groups. No other side effect was observed. These data suggest that the association of Remifentanil, Methylprednisolone, Diclofenac and Tramadol is an useful technique in ambulatory oral surgery in two comparable anesthetic regimens.
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PMID:Use of remifentanil in combination with desflurane or propofol for ambulatory oral surgery. 1153 10

Twenty-one women undergoing termination of pregnancy for severe fetal abnormality received remifentanil and propofol using a target-controlled infusion system and were studied prospectively. Target concentrations were initially set at 1 ng.mL(-1) for remifentanil and 0.8 microg.mL(-1) for propofol. Remifentanil concentration was adjusted to obtain visual analog scores <50 mm with preservation of ventilation. Visual analog scores assessed by the patients and physiologic data were recorded every 15 min until delivery. The median duration of administration was 150 min [10th-90th centiles: 42-282 min). Visual analog scores decreased within the first 5 min (P < 0.05) and remained under 50 mm for 91.7% of time. The median rate of infusion of remifentanil was 0.056 microg.kg(-1) min(-1) [10th-90th centiles: 0.037-0.15 ng.mL(-1)]. At delivery, the median target concentration was 2.2 ng.mL(-1) [10th-90th centiles: 1.25-4 ng.mL(-1)] for remifentanil and 0.8 microg.mL(-1) [10th-90th centiles: 0.32-1.12 microg.mL(-1)] for propofol. Remifentanil requirements were statistically correlated to gestational age, parity and duration of labor. No episodes of ventilatory depression, nausea, vomiting or pruritus were noted. Patients scored analgesia as excellent in 12 cases, good in 7 cases and moderate in 2 cases. Further studies are required to determine the place and the best regimen of remifentanil infusion for pain management in labor in those cases when epidural analgesia is contraindicated.
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PMID:Target-controlled sedation-analgesia using propofol and remifentanil in women undergoing late termination of pregnancy. 1532 93

Remifentanil is a potent mu-opioid receptor agonist and has some unique pharmacokinetic characteristics compared to other anilidopiperidine opioids (e.g. fentanyl, alfentanil, and sufentanil). As remifentanil is metabolised rapidly by nonspecific esterases that are widespread throughout the plasma and tissuses, its duration of action is very short. It is cleared very rapidly, and its clearance is not affected by renal and hepatic function. The context-sensitive half-time of remifentanil remains consistently short, even after administration for a long time. Consequently, emergence is quick even after anesthesia of long duration. As other piperidine opioids, remifentnil has some adverse effects such as respiratory depression, muscle rigidity, bradycardia, and nausea as well as vomiting. Because of the rapid dissipation of analgesic effect following remifentanil discontinuation, postoperative analgesia should be provided before or soon after anesthesia using longer-acting opioid analgesics, non-opioid analgesics, or local as well as regional anesthesia.
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PMID:[Remifentanil]. 1685 41

We performed a quantitative systematic review of randomised, controlled trials that compared remifentanil to short-acting opioids (fentanyl, alfentanil, or sufentanil) for general anaesthesia. Eighty-five trials were identified and these included a total of 13 057 patients. Intra-operatively, remifentanil was associated with clinical signs of deeper analgesia and anaesthesia, such as fewer responses to noxious stimuli (relative risk 0.65, 95% CI 0.48-0.87), more frequent episodes of bradycardia (1.46, 1.04-2.05), more hypotension (1.68, 1.36-2.07) and less hypertension (0.60, 0.46-0.78). Postoperatively, remifentanil was associated with faster recovery (difference in extubation time of -2.03, 9.5% CI, -2.92 to -1.14 min), more frequent postoperative analgesic requirements (1.36, 1.21-1.53) and fewer respiratory events requiring naloxone (0.25, 0.14-0.47). Remifentanil had no overall impact on postoperative nausea (1.03, 0.97-1.09) or vomiting (1.06, 0.96-1.17), but was associated with twice as much shivering (2.15, 1.73-2.69). Remifentanil does not seem to offer any advantage for lengthy, major interventions, but may be useful for selected patients, e.g. when postoperative respiratory depression is a concern.
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PMID:Remifentanil for general anaesthesia: a systematic review. 1799 Dec 65


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