Article

Development of acute opioid tolerance during infusion of remifentanil for pediatric scoliosis surgery

Department of Anesthesia, University of Toronto, Toronto, Ontario, Canada
Anesthesia and analgesia (Impact Factor: 3.42). 06/2006; 102(6):1662-7. DOI: 10.1213/01.ane.0000216036.95705.c2
Source: PubMed

ABSTRACT We tested the hypothesis that continuous intraoperative infusion of remifentanil is associated with the development of clinically relevant acute opioid tolerance in adolescents undergoing scoliosis surgery. Thirty adolescents were randomly assigned to receive an intraoperative analgesic regimen consisting of continuous remifentanil infusion or intermittent morphine alone. Postoperative analgesic consumption was assessed with a patient-controlled analgesia device that was used to self-administer morphine. Cumulative postoperative morphine consumption, pain scores, and sedation scores were recorded by a blinded investigator every hour for the first 4 h postoperatively and then every 4 h for a total of 24 h. Cumulative morphine consumption in the remifentanil group was significantly more than that in the morphine group at each time point in the initial 24 h after surgery (P < 0.0001). At 24 h after surgery, cumulative morphine consumption was 30% greater in the remifentanil group (1.65 +/- 0.41 mg/kg) than in the morphine group (1.27 +/- 0.32 mg/kg) (95% confidence interval for the difference, 0.11 to 0.65 mg/kg). Differences in pain and sedation scores were not statistically significant. These data suggest that intraoperative infusion of remifentanil is associated with the development of clinically relevant acute opioid tolerance in adolescents undergoing scoliosis surgery.

Download full-text

Full-text

Available from: Basem Naser, Mar 14, 2014
0 Followers
 · 
106 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: An important concern of intra-operative infusion of remifentanil is the possible development of acute opioid tolerance, which manifests as an increased postoperative analgesia requirement. We have examined the effect of the timing of intra operative morphine administration on the need for morphine consumption for pain control during the first 24 hours after operation. Sixty adult patients scheduled for elective open unilateral nephrolithotomy surgery were recruited for this prospective randomized double-blind study. Anesthesia was induced with 0.03 mg/kg midazolam, 1 µg/kg remifentanil, and 1.5-2 mg/kg propofol. Anesthesia was maintained with 100 µg/kg/min propofol, and 0.25 µg/kg/min remifentanil. Both groups received 0.1 mg/kg morphine intravenously at 2 different times; in the first group (group E) immediately after intubation and in the second group (group L) 20-30 min before the anticipated end of operation. There was no difference in pain scores at awakening, the amount of morphine given to the 2 groups for pain control, or the time to discharge from PACU between the 2 groups. The pain scores at admission to ward and at every 4 hours thereafter, until 24 hours, were not significantly different between the 2 groups. The cumulative amount of the first 24 hours morphine consumption in the ward in E group was 28.2 ± 20.1 mg and 26.5 ± 15 mg in L group, respectively (P = 0.71). Early intra-operative administration of morphine compared to that of morphine in the end of surgery did not affect postoperative morphine consumption and pain scores during the first 24 hours after surgery for open nephrolithotomy. Newer pharmacologic interventions for prevention of acute tolerance of opioids seems rational (Clinical trial registration No. ACTRN: 12609000570280).
    Korean journal of anesthesiology 09/2012; 63(3):233-7. DOI:10.4097/kjae.2012.63.3.233
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Although acute tolerance to opioids, especially to remifentanil, has been demonstrated consistently in animal studies, the results of clinical trials in humans are controversial. The aim of this study was to determine whether intraoperative infusions of remifentanil used as an adjuvant in general anesthesia result in acute tolerance, an event manifested by increased postoperative pain and a higher opioid requirement than usual. Sixty patients who underwent surgery under general anesthesia for spinal fusion were randomly assigned to receive sevoflurane-nitrous oxide-oxygen (group SO, n = 20), sevoflurane-remifentanil-nitrous oxide-oxygen (group SR, n = 20), or propofol-remifentanil-oxygen (group PR, n = 20) in a double-blinded manner. All patients within 1 hour after induction received PCA (fentanyl 0.4 µg/kg/ml and ondansetron 16 mg) administered intravenously at a basal infusion rate of 1 ml/h, after being intravenously injected with a loading dose of fentanyl (1 µg/kg). Data for fentanyl requirement, verbal Numerical Rating Scale (NRS) pain score at rest, and presence of nausea or vomiting were collected at 1, 24, and 48 hours after surgery. We did not find any significant difference in postoperative PCA fentanyl requirements, NRS or side effects among the groups. Remifentanil as an adjuvant to sevoflurane or propofol in general anesthesia for adults having surgery for spinal fusion does not appear to cause acute opioid tolerance or hyperalgesia in patients. However, further studies are needed to elucidate whether sevoflurane and propofol exert a clinically significant effect on opioid-induced tolerance or hyperalgesia and whether this effect is related to the age of the patient, the dose and duration of remifentanil given and the intensity of pain experienced postoperatively.
    Korean journal of anesthesiology 08/2012; 63(2):103-7. DOI:10.4097/kjae.2012.63.2.103
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Introduction: The use of opioids has been increasing in operating room and intensive care unit to provide perioperative analgesia as well as stable hemodynamics. However, many authors have suggested that the use of opioids is associated with the expression of acute opioid tolerance (AOT) and opioid-induced hyperalgesia (OIH) in experimental studies and clinical observations in dose and/or time dependent exposure even when used within the clinically accepted doses. Recently, remifentanil has been used for pain management during anesthesia as well as in the intensive care units because of its rapid onset and offset. Objectives: Search of the available literature to assess remifentanil AOT and OIH based on available published data. Methods: We reviewed articles analyzing remifentanil AOT and OIH, and focused our literature search on evidence based information. Experimental and clinical studies were identified using electronic searches of Medline (PubMed, Ovid, Springer, and Elsevier, ClinicalKey). Results: Our results showed that the development of remifentanil AOT and OIH is a clinically significant phenomenon requiring further research. Discussions and Conclusions: AOT - defined as an increase in the required opioid dose to maintain adequate analgesia, and OIH - defined as decreased pain threshold after chronic opioid treatment, should be suspected with any unexplained pain report unassociated with the disease progression. The clinical significance of these findings was evaluated taking into account multiple methodological issues including the dose and duration of opioids administration, the different infusion mode, the co-administrated anesthetic drug's effect, method assessing pain sensitivity, and the repetitive and potentially tissue damaging nature of the stimuli used to determine the threshold during opioid infusion. Future studies need to investigate the contribution of remifentanil induced hyperalgesia to chronic pain and the role of pharmacological modulation to reverse this process.
    Frontiers in Pharmacology 05/2014; 5:108. DOI:10.3389/fphar.2014.00108