Dosis de conversión en la rotación de opioides de infusión i.v. continua de morfina a parches de fentanil en el manejo del dolor por cáncer
Dose conversion in opioid rotation from continuous intravenous infusion of morphine hydrochloride injection to fentanyl patch in the management of cancer pain.
Kawano C, Hirayama T, Kuroyama M.
Pharmacy Practice and Science II (Kitasato University East Hospital), School of Pharmacy, Kitasato University. email@example.com Yakugaku Zasshi. 2011 Mar;131(3):463-7.
Opioid rotation has been proposed for management of cancer pain. No studies directly investigating dose equivalence between morphine injection (continuous IV administration) and the transdermal fentanyl patch have been reported. Therefore, we examined dose conversion ratios in patients undergoing opioid rotation from morphine injection to fentanyl patches. The subjects consisted of 45 patients admitted to Kitasato University East Hospital. Medical records were consulted to determine the "basic dose of morphine injection immediately prior to rotation" and the "basic dose of fentanyl patch after rotation". Equivalent doses and conversion ratios obtained with the expression of (daily dose of morphine injection (mg)/daily delivered dose of fentanyl patch (mg)) were determined from the relationship between the data by regression analysis. The regression equation obtained was Y=50.882X-13.96, r²=0.8922, where X and Y are daily doses of morphine injection and fentanyl patch, respectively. Equivalent doses and conversion ratios for daily dose of morphine injection (mg): daily delivered dose of fentanyl patch (mg) (patch dose mg/3 days) were 16.6 mg: 0.6 mg (2.5 mg)=28:1, 47.1 mg: 1.2 mg (5 mg) = 39:1 and 169.2 mg: 3.6 mg (15 mg)=47:1. In other reports, the ratio of morphine vs. fentanyl at 50:1 had no relation to the dose. While the present study suggested that in opioid rotation from low dose, 50:1 is not enough for the fentanyl patch. The dose conversion ratio of morphine injection to fentanyl patch was different at the low doses and high doses of morphine http://www.jstage.jst.go.jp/article/yakushi/131/3/463/_pdf
Cambiando de metadona a diferentes opioides: ¿Cual es la relación de dosis equianalgésicas?
Switching from methadone to a different opioid: what is the equianalgesic dose ratio?
Walker PW, Palla S, Pei BL, Kaur G, Zhang K, Hanohano J, Munsell M, Bruera E.
University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030, USA. firstname.lastname@example.org J Palliat Med. 2008 Oct;11(8):1103-8.
INTRODUCTION: Methadone (ME) is a highly effective opioid agonist used for difficult pain syndromes. However, in the management of cancer pain with strong opioids, rotation to a different opioid (opioid rotation) may be required because of side effects or poor pain control. Rotation from methadone to another opioid has received limited study and therefore may be difficult because of the absence of a uniformly accepted dose conversion ratio.
METHODS: Retrospectively reviewed consecutive medical records of patients undergoing an opioid rotation from methadone to an alternative opioid were evaluated. For inclusion, patients were required to have received methadone for at least 3 days and have reached stable dose of the alternative opioid(s) during the 7 days following. Stable dose was defined as a 30% or less change in opioid dose from one day to the next. RESULTS: Records of 39 patients met inclusion criteria. Excluded from analysis were 5 patients who were restarted on methadone within 7 days, 2 with irregular opioid use resulting in negligible regular opioid doses post-switch, and 3 due to concerns about reliability of multiple routes used for fentanyl. Data from 29 patients, 10 female, mean age 48 +/- 14.4 years, were evaluable. The mean dose ratio for oral methadone to oral morphine equivalent daily dose (MEDD) was 1:4.7 (95% confidence interval [CI], 3.0-6.5; n = 16), and for intravenous (IV) methadone to MEDD was 1:13.5 (95% CI, 6.6-20.5; n = 13), p = 0.06. Methadone dose was significantly correlated to stable MEDD after switching opioids for both methadone IV and oral (Spearman = 0.86, p = 0.0001 and Spearman = 0.72, p = 0.0024), respectively. Mean day of achieving stable dose was day 2.5 +/- 0.2 for IV methadone and day 2.6 +/- 0.3 for oral methadone. CONCLUSION: These dose ratios are new findings that may assist in switching patients more safely to alternative opioids when side effects or pain problems occur when patients are receiving methadone. An important difference in analgesic potency appears to exist between IV and oral ME. Future research with prospective studies is required. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2982711/pdf/jpm.2007.0285.pdf
Estudio de viabilidad de rotación y dosificación rápida de opioides
Feasibility study of rapid opioid rotation and titration.
Korkmazsky M, Ghandehari J, Sanchez A, Lin HM, Pappagallo M.
Mount Sinai Hospital and School of Medicine, Department of Anesthesiology, New York, NY 10029, USA. Pain Physician. 2011 Jan;14(1):71-82.
BACKGROUND: Opioid guidelines recommend opioid rotation and switching for patients who do not achieve adequate pain relief or who experience intolerable adverse events (AEs) with their current opioid. However, specific recommendations and protocols for opioid rotation are lacking, making the practice time consuming and difficult for primary care physicians to accomplish independently or coordinate with a pain specialist. OBJECTIVES: To assess the safety and feasibility of using 24-hour intravenous patient-controlled analgesia (IV-PCA) to achieve rapid opioid rotation and titration (RORT). STUDY DESIGN: Open-label pilot study. SETTING:
Hospital research center. METHODS: At admission, patients (aged ≥ 18 years) with treatment-refractory chronic pain who were taking morphine or oxycodone for ≥ 3 months and had pain scores ≥ 4 on a 10-point scale, underwent opioid rotation to oral oxymorphone extended release (ER). They also received IV-PCA oxymorphone for 24 hours as needed. At discharge, the participants were taking oral oxymorphone ER with oxymorphone immediate release (IR) as needed based on their total 24-hour oral plus IV-PCA oxymorphone use. During a 2-week follow-up, their oxymorphone usage was titrated as needed. Main outcome measures were AEs, Patient Global Impression of Change (PGIC), Brief Pain Inventory (0 = no pain/interference, 10 = worst pain/complete interference), treatment satisfaction, and change in oxymorphone dose. RESULTS: Twelve patients enrolled and completed the 24-hour IV-PCA; 10 completed the 2-week follow-up post-24-hour IV-PCA. PGIC status improved by 12 hours (odds ratio [OR], 0.19, 95% CI, 0.08 - 0.44; P < 0.001), and both PGIC status and activity scores improved by 24 hours (OR, 0.23, 95% CI, 0.09 - 0.55; P = 0.001; OR, 0.49, 95% CI, 0.25 - 0.96; P = 0.04, respectively) and 2 weeks (OR, 0.14, 95% CI, 0.04 - 0.46; P = 0.001; OR, 0.21, 95% CI, 0.06 - 0.72; P = 0.01) versus 6 hours. During the 24-hour IV-PCA time period, 6 of 10 patients accomplished ≥ 50% of their overall dose titration. At 2 weeks, 8 of 10 participants were Greatly Satisfied or Somewhat Satisfied with the overall RORT procedure. RORT was well tolerated, with no serious AEs. LIMITATIONS: This was a pilot open-label study in a small number of participants. A larger randomized study with long-term follow-up and comparison to traditional protocols is necessary. CONCLUSIONS: Preliminary data suggest that RORT can be performed safely and effectively by incorporating IV-PCA during the first 24 hours. Further investigations are needed to determine whether RORT can become an ambulatory treatment intervention in pain practice http://www.painphysicianjournal.com/2011/january/2011;14;71-82.pdf .