Monitoring opioid adherence in chronic pain patients: assessment of risk of substance misuse.

BACKGROUND: Use of opioids for chronic non-cancer pain (CNCP) has increased in recent years because this pain had been undertreated. There was also a simultaneous increase in misuse and abuse of opioids. Deaths due to such abuse and misuse also have risen as seen in the many reports published every day in local papers as well as in the medical literature. So, it is imperative that patients who are prescribed these medications be monitored for adherence so misuse and abuse can be curtailed and opioids are available to those who genuinely need them for chronic pain control. There are various screening tools available to monitor such adherence, and there is an abundance of literature about it in addiction and psychiatric medicine. There is, though, a paucity of such literature as applied to pain medicine. OBJECTIVES: Our objectives for this review were twofold. We wanted to identify which screening tools are available to monitor opioid adherence and we wanted to see if there were prospective comparative studies of these tools to identify a single best tool that can be applied to all chronic non-cancer pain patients managed with opioids. STUDY DESIGN: We did a review of the current literature about monitoring of opioid adherence. We also looked at their use, validity, and comparative studies. METHODS: We performed a literature search using PubMed, EMBASE, and the Cochrane library. The search was conducted using the terms opioids, non-cancer pain, monitoring, and adherence. The databases from 1996 to November 2010 were reviewed. The search included prospective and retrospective studies, review articles, and FDA records. Bibliographies and cross references were reviewed when deemed appropriate. CONCLUSION: We found 52 publications, of which 22 met the criteria to be included in this manuscript. We found only one study that was prospective, and compared the various screening tools that are available to monitor opioid adherence. In the majority of the studies the number treated was small. There was not a single screening tool that can be applied universally to all patients who are on opioid therapy for chronic non-cancer pain.

Respiratory failure following delayed intrathecal morphine pump refill: a valuable, but costly lesson.

BACKGROUND: Spinal analgesia, mediated by opioid receptors, requires only a fraction of the opioid dose that is needed systemically. By infusing a small amount of opioid into the cerebrospinal fluid in close proximity to the receptor sites in the spinal cord, profound analgesia may be achieved while sparing some of the side effects due to systemic opioids. Intraspinal drug delivery (IDD) has been increasingly used in patients with intractable chronic pain, when these patients have developed untoward side effects with systemic opioid usage. The introduction of intrathecal opioids has been considered one of the most important breakthroughs in pain management in the past three decades. A variety of side effects associated with the long-term usage of IDD have been recognized. Among them, respiratory depression is the most feared. OBJECTIVE: To describe a severe adverse event, i.e., respiratory failure, following delayed intrathecal morphine pump refill. CASE REPORT: A 65-year-old woman with intractable chronic low back pain, due to degenerative disc disease, and was referred to our clinic for an intraspinal drug delivery evaluation, after failing to respond to multidisciplinary pain treatment. Following a psychological evaluation confirming her candidacy, she underwent an outpatient patient-controlled continuous epidural morphine infusion trial. The infusion trial lasted 12 days and was beneficial in controlling her pain. The patient reported more than 90% pain reduction with improved distance for ambulation. She subsequently consented and was scheduled for permanent intrathecal morphine pump implantation. The intrathecal catheter was inserted at right paramedian L3-L4, with catheter tip advanced to L1, confirmed under fluoroscopy. Intrathecal catheter placement was confirmed by positive CSF flow and by myelogram. A non-programmable Codman 3000 constant-flow rate infusion pump was placed in the right mid quandrant between right rib cage and right iliac crest. The intrathecal infusion consisted of preservative free morphine, delivering 1.0 mg /day. Over the following 6 months, the dosage was gradually titrated up to 4 mg/day with satisfactory pain control without significant side effects. However, the patient was not able to return to the clinic for pump refill until 12 days later than the previously scheduled pump-refill date. Her pump was accessed and was noted to be empty. Her intrathecal pump was refilled with preservative free morphine, delivering 4 mg/day (the same daily dose as her previous refill). However, on the night of pump refill, 10 hours after the pump refill, the patient was found to be unresponsive by her family members. 911 was called. Upon arriving, paramedics found her in respiratory failure, with shallow breathing at a rate of 5/min, pulse oxymetry showing oxygen saturation about 55-58%. She was emergently intubated on site and rushed to local hospital ER. The on call physician for our clinic was immediately contacted, and advised the administration of intravenous Naloxone. Her respiratory effort improved dramatically after receiving a total of 0.6 mg IV Naloxone IV over 25 minutes. Her intrathecal pump was immediately accessed by clinic on call physician and the remainder of the medication in the catheter space was aspirated. The pump infusate was immediately diluted with preservative free normal saline, to deliver preservative free morphine at 1mg/day. She was transferred to the intensive care unit and extubated the next morning. She recovered fully without any sequelae. CONCLUSION: Loss of opioid tolerance due to delayed pump refill may subject patients to the development of severe respiratory depression. Meticulous approach should be employed when refilling pumps in these patients when their pumps are completely empty. To our knowledge, this is the first reported case of this type.

Bleeding risk in interventional pain practice: assessment, management, and review of the literature.

The rarity of published bleeding complications with respect to the practice of interventional pain medicine suggests two possibilities: techniques are being performed in a manner to minimize bleeding or the process of hemostasis is very forgiving. Hence, bleeding complications may increase if techniques are not performed with due skill or if the process of hemostasis is impaired. Interventional pain physicians may be well acquainted with the technical aspects of procedures, but the degree of their expertise in the field of coagulation is unclear. This monograph will review coagulation physiology, coagulation pathophysiology, common anticoagulants, and minor and major bleeding complications associated with interventional pain and regional anesthetic procedures. This manuscript will present a tool to help stratify the risk of bleeding with specific techniques and specific hemostatic abnormalities. The Overall Risk of Significant Bleeding score may help interventional pain practitioners in their individualized assessment of bleeding risk. If used collectively, this tool may help improve patient safety and data collection, with respect to bleeding complications.

Interventions in chronic pain management. 1. Pain concepts, assessment, and medicolegal issues.

UNLABELLED: This self-directed learning module highlights the concepts of pain and suffering, and chronic pain management from basic science and medicolegal perspectives. It is part of the study guide on chronic pain management in the Self-Directed Physiatric Education Program for practitioners and trainees in physical medicine and rehabilitation. This article specifically focuses on explaining the concepts of pain and suffering as an expert witness, the causes and mechanisms of pain, and qualifying as an expert witness. The article also discusses chronic pain management OVERALL ARTICLE OBJECTIVE: To summarize the concepts of pain and suffering in a medicolegal context.