(747) Open label trial of levetiracetam for chronic lumbar post laminectomy pain
(749) Intra-articular Botulinum toxin for chronic sacroiliac arthropathy pain: A case report
M Wallace, D Zagunis, G Schulteis; University of California, San Deigo, La Jolla, CA This was an open label trial of Levetiracetam (LTM), a new generation anticonvulsant, in subjects with chronic lumbar post laminectomy pain (pain radiating below the knee) of at least 6 months duration. Prior to initiating drug, the following baseline measurements were obtained: 1) Daily Spontaneous Pain Score; 2) Beck Depression Inventory (BDI); 3) Sickness Impact Profile (SIP). Subjects with an average daily spontaneous pain score of ⬎4/10 during the screening period entered a 2 week titration period and started on LTM at 500mg/day and titrated up to 3000 mg/day until they reached a target dose (defined as ⬎30% reduction in pain or ⬍ 30% reduction in pain at the maximum dose). Subjects who reached a target dose were enrolled into a 4 week maintenance period. At the completion of the maintenance period, the baseline measurements were repeated. Eighteen subjects enrolled in the study with 14 completing the titration. Four subjects dropped out of the titration period due to side effects. The average daily dose of LTM at the end of titration was 2303 mg. Three subjects elected not to continue into the maintenance period due to lack of efficacy. Four out of the 18 subjects were considered responders (⬎ 30% reduction in pain) with a mean of 55% reduction in pain. The mean baseline BDI score for responders and non responders was 2.25 and 17.5 respectively. The SIP score for responders and non responders was 16.25 and 48.85 respectively. 3 out of 4 responders had SIP scores below 10. Overall, LTM resulted in a small non significant decrease in pain score (baseline mean 59.3, end of maintenance mean 49.1). This study suggests that LTM is effective in lumbar post laminectomy pain patients with low baseline BDI and SIP scores. Further investigation of LTM in neuropathic pain is warranted.
S Schocket, T Moeller-Bertram; UCSD Center for Pain Management, La Jolla, CA Sacroiliac joint pain is estimated to account for 15% of all patients with chronic LBP. Current treatment interventions include intra-articular local anesthetic and steroid injections and radiofrequency denervation of dorsal rami. Unfortunately, neither provides consistent, long-lasting pain relief. We report a case of repeated botulinum toxin injections into the SI joint resulting in excellent and prolonged pain relief. A 62 year old man was referred to our pain clinic for treatment of chronic low back pain. His previous treatment included a series of lumbar trigger point injections first with local anethetic and steroid followed by botox, providing moderate relief for less than 4 weeks. Subsequently, the patient underwent a right SI joint injection using 3 cc of 0.75% Marcaine and 40 mg Depo-Medrol, providing 100% relief of his pain for 2 weeks duration. We then offered the patient intra-articular Botox injections to potentially prolong the pain relief. Subsequently, he received an injection into the right sacroiliac joint of 100 units of Botox diluted in 2-3 cc Marcaine, resulting in 100% pain resolution for 4 weeks, and 80% pain reduction at 6 weeks post-injection. A 2nd injection, performed 7 weeks after the initial injection, provided 6 weeks of 100% pain reduction and additional 6 weeks of 70-80% pain reduction. His injections were repeated every 3 months for a total of 10. He consistently was pain free for 8-10 weeks with minimal pain scores in the 2-4 weeks prior to the next injection. He experienced no side effects and didn’t develop resistance to the botulinum toxin over a 25 month period. Injection of Botox into the sacroiliac joint provided safe, consistent, and persistant pain relief and represents a promising modality for long-term treatment of all sacroiliac joint patients.
(748) Clinical importance of changes in pain intensity: An analysis of data from clinical trials of duloxetine in pain disorders
(750) Intravenous lidocaine: Sustained pain relief from a single infusion
J Farrar, Y Pritchett, M Robinson, J Watkin, A Chappell; Eli Lilly and Company, Indianapolis, IN Previous studies have suggested that the 0-10 numerical rating scale for pain intensity is best analyzed as a percentage change and that a reduction of approximately 30% represents a clinically important improvement. We utilized pooled data from clinical trials of duloxetine, a dual reuptake inhibitor of serotonin and norepinephrine, to validate these findings for the treatment of chronic pain in a different clinical trial setting. Data were obtained from 5 double-blind, randomized, placebocontrolled trials of duloxetine (20 mg QD - Study 1 only, 60 mg QD, or 60 mg BID) in patients with diabetic peripheral neuropathic pain (Study 1, N⫽457; Study 2, N⫽334; Study 3, N⫽348) or fibromyalgia syndrome (Study 4, N⫽207; Study 5, N⫽354). Efficacy measures included the pain intensity and interference scales of the Brief Pain Inventory (BPI), and the Patient Global Impression of Improvement (PGI-I) scale. We defined clinically important improvement as PGI-I categories of ‘much better’ and ‘very much better.’ The relationship between the BPI and the PGI-I were assessed using receiver operating characteristic curve analyses. The overall relationship between change in BPI pain intensity and the PGI-I scale remained consistent when patients were stratified by sex, age, disease state, and treatment group, but separated when stratified by baseline pain. Percent change resulted in a more consistent association. The average change in pain severity best associated with a clinically important improvement was a decrease from baseline of approximately 1.9 points or a 33% reduction. The same analyses for the BPI pain interference scales demonstrated a similar association with the PGI-I. The pain intensity results are consistent with those obtained for other analgesics and the pain interference results correlate well with the PGI-I. These findings enhance our understanding of patient-determined clinically important improvement in pain intensity and interference in chronic pain patients.
G McCleane; Rampark Pain Centre, Lurgan, United Kingdom The first description of the use of an intravenous local anesthetic as an analgesic appeared over 60 years ago. Many reports since then have confirmed this effect and yet the use of intravenous local anesthetics have not become widespread practice. In a study of twenty adult patients with chronic pain of mixed etiology (including neuropathic pain and fibromyalgia), each patient received an intravenous infusion of 1200mg of lidocaine over 12 hours, pain scores 10cm LVAS) fell from a pretreatment average of 7.8 to a daily average of 4.4 for the first week and daily averages of 4.1, 3.9, 3.5,4.2 and 5.8 for the second, third, fourth and fifth weeks. Average daily number of analgesic tablets fell from 7.1 to a dailt average of 4.8 in the first week. This decreased anagesic consumption persisted for 5 weeks. No patient complianed of any adverse effect during or after the infusion period. Therefore, a single intravenous infusion of lidocaine over a 12 hour period produced pain relief that persisted for five weeks with was accompanied by a significant reduction in analgesic consumption. Lidocaine is cheapp, and if the results of this small study are correct, an effective method of producing pain relief associated with few adverse effects.