Public Release:  Severe pain relief may be possible with a common anesthetic drug

Blackwell Publishing Ltd.

A novel treatment using a common anesthetic drug has shown success in reducing the severe pain caused by Complex Regional Pain Syndrome (CRPS), according to a study published in the September 2004 issue of Pain Medicine. CRPS, a disorder that can be associated with chronic pain resistant to conventional therapies, affects between 1.5 and 7 million people in the United States. CRPS is sometimes also known as Reflex Sympathetic Dystrophy (RSD).

"This pain disorder can be very difficult to treat. Currently-available conventional therapies, at best, oftentimes only make the pain bearable for many CRPS sufferers," said Ronald E. Harbut, MD, PhD, of Penn State Milton S. Hershey Medical Center, corresponding author of the study. "In our retrospective study, some patients who underwent a low-dose infusion of ketamine experienced complete relief from their pain, suggesting that this therapy may be an option for some patients with intolerable CRPS."

Thirty-three patients with unrelenting CRPS were treated using this novel approach developed by Dr. Graeme E. Correll, BE, MBBS, in Mackay, Queensland, Australia. Pain relief and the duration of this relief appeared impressive. After only one treatment, there was complete relief in 76% (25) of the group. 54% of the patients remained free of pain for more than three months, 31% for more than six months. Although the relief of pain did not last indefinitely, it was noted that following a second treatment given to 12 of the patients, the outcome was improved. In this retreated group 58% remained pain free for more than a year and almost 33% experienced relief for over three years. The most frequent side effect was a feeling of inebriation with less frequent effects including hallucinations, dizziness, light-headedness and nausea.

"Ultimately, we want to find a way to improve the quality of life for those who suffer with intolerable and endless CRPS -- that is our hope," said Harbut. Although optimistic about these early findings, "Certainly more study is needed to further establish the safety and efficacy of this novel approach." (A large clinical study is currently planned and under development at Penn State Hershey Medical Center.)

Rollin M. Gallagher, MD, MPH, Editor-in-Chief of Pain Medicine, notes, "How medical breakthroughs occur is usually a story of human ingenuity and perseverance fueled by compassion and intellect. Dr. Correll's promising innovation, forged by necessity in tiny resource-poor clinics in the jungles of Papua-New Guinea and Northern Australia and carefully shepherded to publication by his co-authors, may herald an effective treatment for one of mankind's most enigmatic and agonizing diseases. Prospective, controlled studies must follow to establish its safety and efficacy."

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Media wishing to receive a PDF of this article, please contact medicalnews@bos.blackwellpublishing.net. Additional information about CRPS can be found at www.rsdhope.org.

About the Authors
Graeme E. Correll, BE, MBBS, a Fellow of the Australian & New Zealand College of Anaesthetists, has been an anesthesiologist for over 30 years. He originally worked as an anaesthetist (anesthesiologist) in Papua-New Guinea (PNG) for 5 years in the remote jungle communities of Lae and Rabaul. As anesthetic resources were limited in these isolated areas, Correll relied heavily on the intravenous anesthetic ketamine. Under these unique working conditions, Correll became exceptionally experienced in the administration of this medication. Correll later moved to Mackay, where he continued his profession for over 20 years as the principal anaesthetist in what started out as a small sugar-cane community in tropical northern Queensland. While in Mackay, he used his anesthetic experience from PNG to eventually help him sort out and develop a treatment method using low doses of ketamine that met the analgesic needs of his chronic pain patients. He initiated this novel approach to treating CRPS, while he was senior anaesthetist (anesthesiologist) at Mackay Base Hospital.

Ronald E. Harbut, MD, PhD, Assistant Professor of Anesthesiology at Penn State Hershey Medical Center, is Board Certified in Anesthesiology and Pain Medicine and has a background in both Pharmacy and Pharmacology. Harbut first met Correll while working in Australia in the late 1990s. While in Australia, Harbut was impressed with Correll's findings and the two began collaborative relationships that eventually led to the Mayo Clinic Scottsdale. While at Mayo, Correll and Harbut's belief in a value of this unique approach to treating neuropathic pain was furthered along by colleague Jesse J. Muir, MD, who likewise shared a special interest in the treatment of neuropathic pain. Working together, Correll's technique was brought to the United States.

Other members of the research team include: Jahangir Maleki, MD, PhD, Assistant Professor of Neurology, and Edward J. Gracely, PhD, Associate Professor of Family, Community and Preventive Medicine and Public Health. Both are from Drexel University College of Medicine in Philadelphia. Maleki, who trained in psychiatry in Germany and in neurology, neurophysiology, and pain medicine in the United States, was instrumental with Harbut in writing this manuscript. Gracely provided biostatistical analysis. Jesse J. Muir, MD, Assistant Professor of Anesthesiology at Mayo Clinic Scottsdale, is Board Certified in Anesthesiology and Pain Medicine. He has served as both Pain Clinic and Pain Medicine Fellowship Director at Mayo Clinic Scottsdale.

Special recognition goes to Drs Maleki and Gracely for their analysis of these data, to Drs Maleki and Muir for their help in developing this manuscript, and to the Editorial Board of Pain Medicine for their support and suggestions.

About Pain Medicine
Pain Medicine, the official journal of the American Academy of Pain Medicine, is a multi-disciplinary journal dedicated to the pain clinician, teacher and researcher. The journal reflects the rapid growth in the area of pain research and management. Readers benefit from the most up-to-date information available on the practice of pain medicine as the journal promotes both visibility and credibility of pain medicine as a medical specialty. For further information, please visit www.blackwellpublishing.com/pme.

About the American Academy of Pain Medicine
Founded in 1983, the American Academy of Pain Medicine (AAPM) has evolved as the primary organization for physicians practicing the specialty of Pain Medicine in the United States. The organization is devoted to the advancement of pain management, education and research. AAPM is the only pain organization with representation in the American Medical Association (AMA) House of Delegates. For membership information and benefits - including your subscription to Pain Medicine - visit www.painmed.org.

About The National Pain Foundation
If you are looking for additional resources and information on pain, please visit www.painconnection.org. The National Pain Foundation, a non-profit 501(c)(3) organization, was established in 1998 to advance functional recovery of persons in pain through information, education and support. The NPF is built on the belief that early intervention of pain conditions can positively change the direction of a person's life.

About Blackwell Publishing
Blackwell Publishing is the world's leading society publisher. The company remains independent with over 900 staff members in offices in the US, UK, Australia, China, Denmark, Germany, and Japan. Blackwell publishes over 700 journals in partnership with more than 550 academic and professional societies.

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