The American Society of Pain and Neuroscience (ASPN) Guidelines for Radiofrequency Ablative Procedures in Patients with Implanted Devices

Radiofrequency ablation (RFA) is a treatment modality used in interventional pain management to treat several conditions including chronic neck or back pain, sacroiliac joint pain, major joint pain, and pain from sites that can be isolated to a sensory nerve amenable to RFA. The goals of such procedures are to reduce pain, improve function, delay need for surgical intervention, and reduce pain medication consumption. As applications for RFA expand through novel techniques and nerve targets, there is concern with how RFA may impact patients with implanted medical devices. Specifically, the electrical currents used in RFA produce electromagnetic interference, which can result in unintentional energy transfer to implanted devices. This may also interfere with device function or cause damage to the device itself. As the number of patients with implanted devices increases, it is imperative to establish guidelines for the management of implanted devices during RFA procedures. This review aims to establish guidelines to assist physicians in the preoperative, intraoperative, and postoperative management of implanted devices in patients undergoing procedures using radiofrequency energy. Here, we provide physicians with background knowledge and a summary of current evidence to allow safe utilization of RFA treatment in patients with implanted devices such as cardiac implantable electronic devices, spinal cord stimulators, intrathecal pumps, and deep brain stimulators. While these guidelines are intended to be comprehensive, each patient should be assessed on an individual basis to optimize outcomes.

Interventional Pain Procedures: A Narrative Review Focusing On Safety and Complications. PART 2 Interventional Procedures For Back Pain

In patients where conservative approaches have failed to relieve from chronic pain, interventional procedures may be an option in well selected patients. In recent years there has been an increase in the use and development of invasive procedures. Concomitantly, there has also been an increase in the complications associated with these procedures. Taken this into consideration, it is important for healthcare providers to take a cautious and vigilant approach, with a focus on patient safety, in order to minimize the risk of adverse events and ensure the best possible outcome for the patient. This may include careful selection of patients for procedures, use of proper techniques and equipment, and close monitoring and follow-up after the procedure. The aim of this narrative review is to summarize the primary complications associated with commonly performed image-guided (fluoroscopy or ultrasound-guided) interventional procedures and provide strategies to reduce the risk of these complications. We conclude that although complications from interventional pain procedures can be mitigated to a certain degree, they cannot be eliminated altogether. In order to avoid adverse events, patient safety should be given considerable attention and physicians should be constantly aware of the possibility of developing complications.

Piezoelectric ultrasound energy-harvesting device for deep brain stimulation and analgesia applications

Supplying wireless power is a challenging technical problem of great importance for implantable biomedical devices. Here, we introduce a novel implantable piezoelectric ultrasound energy-harvesting device based on Sm-doped Pb(Mg_1/3Nb_2/3)O₃-PbTiO₃ (Sm-PMN-PT) single crystal. The output power density of this device can reach up to 1.1 W/cm² in vitro, which is 18 times higher than the previous record (60 mW/cm²). After being implanted in the rat brain, under 1-MHz ultrasound with a safe intensity of 212 mW/cm², the as-developed device can produce an instantaneous effective output power of 280 μW, which can immediately activate the periaqueductal gray brain area. The rat electrophysiological experiments under anesthesia and behavioral experiments demonstrate that our wireless-powered device is well qualified for deep brain stimulation and analgesia applications. These encouraging results provide new insights into the development of implantable devices in the future.

North American Neuromodulation Society Educational Curriculum for Intrathecal Drug Delivery Systems Implantation and Management

OBJECTIVES

Intrathecal drug delivery systems (IDDSs) are used for the treatment of pain and spasticity. A wide range of educational criteria exist for these devices. The North American Neuromodulation Society (NANS) Education Committee developed a comprehensive IDDS curriculum to function as a standard for physician graduate education and assessment through training and into practice.

MATERIAL AND METHODS

A multidisciplinary and diverse task force gathered by the NANS Education Committee met in person and virtually over several sessions and developed an IDDS curriculum modeling their previous work on spinal cord stimulation and following the Accreditation Council for Graduate Medical Education (ACGME) Milestones. There were iterative revisions and adaptations to the curriculum, and the final version was approved by the NANS Board of Directors.

RESULTS

The curriculum was developed with distinction between implanting physicians and managing physician and physicians who perform both tasks. There is a lateral temporal progression from early learner to practitioner, with advanced learner in the middle. In addition, there is a modular vertical organization that divides the curriculum into the six educational competencies outlined by the ACGME.

CONCLUSION

A comprehensive, modular, graduated, and segmented educational curriculum for IDDSs was developed by NANS. We propose the curriculum to be the standard for guidance and assessment of trainees and physicians pursuing training in implanting or managing IDDSs.

Intrathecal Analgesia in Cancer Pain

The number of new cancer cases has been increasing globally over the last several decades.

Intravenous prostacyclin-analogue therapy in pulmonary arterial hypertension - A review of the past, present and future

Therapy with intravenous prostacyclin analogues in patients with pulmonary arterial hypertension (PAH) has been established for decades and is an integral component of the current guidelines for the treatment of pulmonary hypertension. Initially, these drugs were infused by external pump systems via tunnelled right atrial catheters with the need for cooling and frequent exchange of drug reservoirs. Associated complications included, among others, catheter-related infections. More recently, fully implantable pump systems have been developed with drug reservoirs that are filled transcutaneously, allowing intervals between refills of several weeks. This technique results in a low rate of infections. Epoprostenol, iloprost and treprostinil have all been used intravenously in PAH, but titration, dosing and dose escalation in long-term therapy are not standardized. Intravenous prostacyclin analogues are still under-used, despite available data suggesting that early and broad application of these therapies as part of risk-oriented, guideline-directed combination therapy for patients with PAH may lead to a survival benefit. This review provides a detailed overview of the drugs, infusion systems and dosing strategies used for intravenous therapy in patients with PAH.

Narrative review of intrathecal drug delivery (IDD): indications, devices and potential complications

The management of chronic refractory pain (non-neoplastic and cancer-related pain) remains a therapeutic challenge. The continuous intrathecal (IT) administration of drugs may play an important role in the possible management options. Intrathecal drug delivery devices (IDDDs) may be effective for patients with refractory chronic pain. Therefore, they may be adopted for non-oncologic pain in patients with compression fractures, spondylolisthesis, spondylosis, back surgery failure syndrome and spinal stenosis. Oncologic patients can benefit from these treatments in a variable way according to tumor characteristics, prognosis, periprocedural imaging and risk of disease progression. In this review, we describe the most commonly used drugs (opioids and non-opioids), their pharmacokinetic and pharmacodynamic features and indications of use. The most used drugs are morphine, hydromorphone, fentanyl, methadone, bupivacaine, clonidine, and ketamine. Patient evaluation before the device implantation should be based on clinical examination, medical records assessment and psychometric evaluation. The infusion pumps available on the market are both non-programmable (with continuous IT deliver of drugs) and programmable (with variable deliver of drugs according to their flow rate). Moreover, we describe the procedure of implantation and the potential complications of IT drug delivery (such as bleeding, infection, loss of cerebrospinal fluid, wound seroma, loss of catheter pump propellant).

Intrathecal Therapy for Chronic Pain: A Review of Morphine and Ziconotide as Firstline Options

Objectives

To evaluate the evidence for morphine and ziconotide as firstline intrathecal (IT) analgesia agents for patients with chronic pain.

Methods

Medline was searched (through July 2017) for “ziconotide” or “morphine” AND “intrathecal” AND “chronic pain,” with results limited to studies in human populations.

Results

The literature supports the use of morphine (based primarily on noncontrolled, prospective, and retrospective studies) and ziconotide (based on randomized controlled trials and prospective observational studies) as first-choice IT therapies. The 2016 Polyanalgesic Consensus Conference (PACC) guidelines recommended both morphine and ziconotide as firstline IT monotherapy for localized and diffuse chronic pain of cancer-related and non–cancer-related etiologies; however, one consensus point emphasized ziconotide use, unless contraindicated, as firstline IT therapy in patients with chronic non–cancer-related pain. Initial IT therapy choice should take into consideration individual patient characteristics (e.g., pain location, response to previous therapies, comorbid medical conditions, psychiatric history). Trialing is recommended to assess medication efficacy and tolerability. For both morphine and ziconotide, the PACC guidelines recommend conservative initial dosing strategies. Due to its narrow therapeutic window, ziconotide requires careful dose titration. Ziconotide is contraindicated in patients with a history of psychosis. IT morphine administration may be associated with serious side effects (e.g., respiratory depression, catheter tip granuloma), require dose increases, and cause dependence over time.

Conclusion

Based on the available evidence, morphine and ziconotide are recommended as firstline IT monotherapy for cancer-related and non–cancer-related pain. The choice of first-in-pump therapy should take into consideration patient characteristics and the advantages and disadvantages of each medication.

Cementless versus cemented total knee arthroplasty in young patients: a meta-analysis of randomized controlled trials

Purpose

Optimal type of prosthesis in total knee arthroplasty (TKA) remains controversial for young patients. The objective of this meta-analysis is to compare cementless and cemented fixation in TKA.

Methods

In this meta-analysis, we conducted electronic searches of PubMed, Embase, Cochrane Library, and Web of Science in December 2018. We collected randomized controlled trials (RCTs) comparing cementless and cemented TKA in young patients. The outcome measurements consisted of functional outcomes, Knee Society Score, range of motion, radiological outcomes, pain score, and complications. Stata 12.0 software was used for our meta-analysis. Quality assessment for RCTs was conducted according to the Cochrane Handbook for systematic review of interventions.

Results

Four RCTs met our inclusion criteria with 255 patients in cemented groups and 229 patients in cementless groups. The present meta-analysis indicated that there was a significant difference between the groups in terms of radiological outcomes and pain score. No significant difference was found regarding KSS, range of motion, or complications.

Conclusion

Cementless TKA was associated with superior outcomes in terms of radiological outcomes and pain score compared with cemented fixation. We found no significant difference regarding the functional outcome or aseptic loosening between groups. High-quality RCTs were still required for further investigation.

The Role of Neuraxial Opioids in Pediatric Practice

Neuraxial-spinal and epidural-administration of opioids can be an effective method for controlling pain for children in a number of clinical settings. Understanding the basic pharmacologic and logistical concepts will make it easier for pediatricians to advocate for their patients, and support patients and families when circumstances suggest that neuraxial opioid treatment is appropriate. This review article summarizes the basic concepts of pharmacology, drug choice, side effects, and complications as well as situations in which neuraxial opioids are appropriate in children.

Role of primary care physicians in intrathecal pain management: a narrative review of the literature

OBJECTIVES

The majority of patients seeking medical care for chronic pain consult a primary care physician (PCP). Because systemic opioids are commonly prescribed to patients with chronic pain, PCPs are attempting to balance the competing priorities of providing adequate pain relief while reducing risks for opioid misuse and overdose. It is important for PCPs to be aware of pain management strategies other than systemic opioid dose escalation when patients with chronic pain fail to respond to conservative therapies and to initiate a multimodal treatment plan.

METHODS

The Medline database and evidence-based treatment guidelines were searched to identify publications on intrathecal (IT) therapy for the management of chronic pain. Selection of publications relevant to PCPs was based on the authors' clinical and research expertise.

RESULTS

IT administration delivers analgesic medication directly into the cerebrospinal fluid, avoiding first-pass effect and bypassing the blood-brain barrier, thereby requiring lower medication doses. Morphine, a µ-opioid receptor agonist, and ziconotide, a non-opioid, selective N-type calcium channel blocker, are the only analgesics approved by the US Food and Drug Administration to treat chronic refractory pain by the IT route. Patients who are potential candidates for IT therapy may benefit from evaluation by an interventional pain physician. PCPs can play an important role in patient selection and referral for IT therapy and provide ongoing collaborative care for patients receiving IT therapy, including monitoring for efficacy and adverse events and facilitating communication with the treating specialist.

CONCLUSIONS

Collaboration between PCPs and pain specialists may improve outcomes of and patient satisfaction with IT therapy and other interventional treatments.

Intravenous treprostinil infusion via a fully implantable pump for pulmonary arterial hypertension

OBJECTIVES

Parenteral prostanoids infused via external pumps are well-established pulmonary arterial hypertension (PAH) treatments. However, local side-effects and systemic infections restrict their use. The purpose of this study was to investigate the safety of a fully implantable treprostinil infusion pump (LENUS Pro^®) in patients with PAH.

METHODS

Thirty patients with PAH undergoing pump implantation (with stable PAH therapy for ≥3 weeks pre-implantation) were included in this prospective, multicenter, observational study (NCT01979822). Primary endpoints were predefined adverse events (AEs) during implantation, in-hospital and/or during 6-month follow-up. Refill-related AEs were a secondary endpoint.

RESULTS

Twenty-nine patients completed 6-month follow-up (one underwent lung transplantation). During implantation, one pneumothorax (not requiring drainage) occurred. Four patients had an in-hospital AE (including one catheter revision). During 6-month follow-up, AEs were most frequent at the first refill (10); the most common AE was seroma around the pump. No infections occurred. One pump required replacement because of a defective septum caused by use of a non-approved refill needle (associated with extravasation). Apart from the extravasation, no refill-related AEs were recorded. Post hoc efficacy analyses showed significant improvements in functional class [number in functional class I/II/III/IV: 0/5/21/2 (baseline) versus 3/8/17/0 (6 months); p = 0.012] and 6-min walk distance (mean ± standard deviation: 407 ± 122 m versus 445 ± 127 m; n = 17; p = 0.014).

CONCLUSIONS

This study supports use of a fully implantable treprostinil infusion pump in patients with PAH requiring parenteral prostanoids. Refills should be performed by specialized healthcare professionals at patients' homes or at experienced centers using approved equipment.

Synthesis and biological evaluation of fentanyl acrylic derivatives

Synthesis and biological evaluation of fentanyl acrylic derivatives.

Prevention of intrathecal drug delivery catheter-related complications

In an effort to improve the performance of implantable intrathecal drug delivery systems, a group of physicians experienced in the management of such devices reviewed surgical practices and principles that were associated with low catheter-related complication rates. Clinical study and postmarket data identified physicians whose patients experienced a relatively low rate of catheter-related complications. Six of those physicians (three anesthesiologists and three neurosurgeons) reviewed the number and types of intrathecal drug pumps and catheters they had implanted, with an emphasis on the specific details of successful catheter implantation techniques. The authors pooled their experiences to reach a consensus on implant techniques that are associated with a low rate of postoperative complications.  The authors found that complications were minimized by the use of specific methods for catheter placement that included: a mid-to-upper lumbar dural entry level, a shallow-angle paramedian oblique insertion trajectory, and meticulous catheter anchoring and tunneling techniques. Systemic antibiotic prophylaxis, attention to pump pocket location, and surgical wound closure techniques also were important in reducing the incidence of postoperative device-related complications. Their experience indicates that specific implantation techniques using a variety of catheters and accessories can be expected to reduce the incidence of complications after implantation of intrathecal drug administration systems.

The effects of long-term intraspinal infusion therapy with noncancer pain patients: evaluation of patient, significant-other, and clinic staff appraisals

Objective. This study examines, in a retrospective fashion, the effects of intraspinal infusion therapy, primarily using opioids, in the treatment of recalcitrant noncancer pain in a sample of 29 consecutive patients. Patients were, on average, 58 years of age having had one surgery, with a pain duration of 221 months. Mean follow-up duration was 31 months. Telephone interviews by a disinterested party were used to obtain follow-up data from patients and their significant others. In addition, clinic staff rated patient improvement. Results. The patients reported an average of 63.4% improvement in pain; 45.5% improvement in activity level; and a 53.8% improvement in "ease" of performing activities. Average pain level on a numerical rating scale decreased from 8.91/10 to 5.03/10. The number of patients reporting a pain level of 5/10 or less increased from 1/29 to 15/29. Patients generally reported long-term benefit to be equal to or greater than that realized during the intrathecal trial. Approximately 86% of patients reported a "good" or "excellent" outcome. Significant-other ratings of improvement correlated more highly with clinic staff than with patients. No statistically significant differences were observed when worker's compensation (WC) patients were compared with nonworker's compensation (NWC) patients. Nearly 50% of the patients reported some type of transient or persistent side effect, mostly related to the infused substance. No mechanical failure of the DAS system was observed. Conclusion. These results in part replicate those from previous studies examining the long-term effects of infusion therapy. Side effects remain fairly common and require continued attention. Their presence, however, did not appear to deter from the patient's overall sense of satisfaction. Acquiring information from significant others and clinic staff may be a useful adjunct in interpreting the overall outcome.

Spinal morphine in nonmalignant chronic pain: a retrospective study in 39 patients

It was the purpose of this study to retrospectively test the safety and efficacy of the use of intraspinal analgesics in a diverse population of patients with chronic nonmalignant pain. This study was conducted in 39 patients, refractory to conventional therapies for intrathecal therapy. Twenty-two patients had neuropathic pain and 17 had nociceptive pain. The mean follow-up of this patient population was 2.2 years with a range of 36 months to 6.5 years. Analgesia with intraspinal morphine, initial and final dose of intraspinal agents used, stability of morphine dose over time, and side effects and complications with or without bupivacaine and/or clonidine was assessed after 6 months of treatment, and at the end of study. After 6 months, three patients discontinued the study for differing reasons, 28 patients (77.8%) reported excellent results, and five patients (14%) reported good results. One patient reported no pain relief with intraspinal morphine and bupivacaine and five patients reported insufficient or no pain relief. At final assessment, 20 patients (55.6%) reported excellent results with no differences based on pain type or pain syndrome and eight patients (22.2%) reported good analgesia. Morphine doses remained stable throughout treatment, with an average dose of 2 mg per patient. Ninety-one percent of patients were satisfied with the method used and considered it superior to all previous therapeutic techniques tried, improving their quality of life. As for complications, one patient developed a clostridial infection during the immediate postoperative period which required pump removal and one patient developed severe urinary retention requiring system removal. There were three catheter obstructions (two in the same patient) and one catheter disconnection. Other patient-reported side effects were not considered significant by the authors to be mentioned here. After more than 6 years of experience with spinal infusion of morphine, either alone or admixed with other spinal analgesics, in patients with pain of nonmalignant origin, we consider the technique to be helpful in selected patients not responding to oral treatment or when untoward side effects exist with oral treatment. The advantages, as regards to analgesic efficacy and quality of life, clearly outweigh the drawbacks of the long-term use of spinal morphine.

Multiple lead spinal cord stimulation for chronic mechanical low back pain: a comparative study with intrathecal opioid drug delivery

The objective of this paper is to assess the outcome of implanted multiple thoracolumbar lead spinal cord stimulation (SCS) in mechanical back pain without prior spinal surgery. These results are compared with intrathecal opioid drug delivery (ITDD). An anonymous third party patient questionnaire study of pain relief, function and psychosocial quality of life measures (recorded on 11-point numerical rating scales) for 12 patients with SCS and 13 with ITDD was used. Pain was significantly reduced with multiple lead SCS from a median of 9.0-6.5 (p < 0.01) and with ITDD from a median of 8.5-5.5 (p < 0.01). There was a trend towards greater reduction in pain in the ITDD group compared with the SCS group (pain differences 4.5 and 2.6, respectively) but this did not reach statistical significance. The majority of psychosocial quality of life measures were significantly more improved in the ITDD group compared with the SCS group (p < 0.05). We conclude that multiple-lead SCS improves mechanical back pain in patients unresponsive to more conservative measures. However, ITDD provides significantly more improved quality of life measures, with a trend towards greater pain reduction than SCS.

Spinal infusion pump-catheter leak detected by high-resolution 3D computed tomography

Implanted intrathecal drug delivery systems may malfunction as a result of fracture of the intrathecal catheter. A suspected catheter fracture not seen on plain radiographs of the catheter system will typically prompt a contrast-enhanced imaging study of the pump. Injection of iodinated contrast medium into the pump system with routine fluoroscopy can sometimes fail to reveal subtle leaks. The authors present a case demonstrating the utility of high-resolution, 3D-CT for intrathecal pump-catheter system interrogation when routine fluoroscopy is unrevealing. In this case, a catheter leak was suspected on the basis of the patient's history, but no obvious fracture was noted on plain radiographs. An intraoperative fluoroscopic study that included multiple injections of contrast medium into the catheter system failed to conclusively show a catheter leak. The authors therefore performed a post-injection 3D-CT study, which clearly demonstrated a leak from the intrathecal catheter just deep to the thoracolumbar fascia. The leak was visible on source images and was especially obvious after 3D reconstruction. This led to surgical revision of the catheter and subsequent resumption of normal pump function. The authors therefore suggest that if a leak is suspected in an implanted intrathecal catheter and routine contrast fluoroscopy is unrevealing, post-injection 3D-CT scanning should be performed to further investigate the possibility of a subtle leak.

Eliciting health state utilities from the general public for severe chronic pain

OBJECTIVE

There is an absence of data on public preferences for health states (HSs) associated with severe chronic pain. The aim of this study was to develop accurate HS descriptions for severe chronic pain requiring intrathecal (IT) therapy and to derive utility weights that describe the health-related quality of life (HRQL) impact of chronic pain associated with malignant (MP) and non-malignant (NMP) aetiologies.

RESEARCH DESIGN AND METHOD

Eight visual analogue scale pain index (VAS-PI) HSs were defined using ranges 0-40, 41-60, 61-80 and 81-100 applied to both MP and NMP. Additionally, eight HSs representing common adverse events associated with IT therapy were identified. The content and description of the HSs were ascertained by interviews with five United Kingdom clinical experts. In total, 16 HSs were compiled. These HS descriptions and HS questionnaires were administered to 102 members of the public, utilising a time trade off (TTO) approach to estimate utilities for the HSs.

RESULTS

Participants generally were well matched to the general public in England and Wales, with some differences in mean age, race and education. A substantial decline in utility was observed with more severe VAS-PI values. The mean TTO utility values also decreased from mild pain to severe pain. Participants were able to differentiate between the side effects.

CONCLUSION

The study shows a clear decrement in utility moving from different severity levels of severe chronic pain.

Intrathecal infusions for intractable cancer pain: a qualitative study of the impact on a case series of patients and caregivers

BACKGROUND

The need for intrathecal infusion in a palliative care setting is infrequent. Despite established efficacy, safety and cost effectiveness, this is considered an 'extraordinary measure' in Canada. Patients requiring this approach are not typical palliative care patients, having shorter and more uncertain life expectancies.

OBJECTIVES

The present study is a qualitative exploration of the impact of intrathecal pump implantation on cancer patients, and also the impact of the intervention on the staff caring for those patients.

METHODS

Palliative care unit patients who received an implanted intrathecal pump or dome catheter for intractable cancer pain participated in multiple semistructured interviews. Doctors and nurses caring for each patient were also interviewed. Interviews were recorded and analyzed for themes. The study terminated when saturation was reached.

RESULTS

Six patients participated, with up to three interviews each. Twenty-four staff interviews took place. Patients' hopes and expectations were not always fully met, but the infusions had a profound positive effect on quality of life. Patients expressed anxiety about dependence on the device, and also on a few highly skilled individuals. Staff interviews revealed a significant impact on the 'culture' of the palliative care unit. Clear communication of the rationale for infusion was very important, as was regular education about infusion management.

CONCLUSIONS

Implanted intrathecal infusion devices are a necessary part of a tertiary level cancer pain management service for the unfortunate minority with intractable pain. Practical recommendations for care are made for palliative care programs contemplating offering intrathecal infusions.

[Spinal granuloma in a patient receiving a spinal infusion of morphine and clonidine]

Patients treated with long-term spinal infusion of high doses of morphine develop a granuloma at the location of the catheter tip. Diagnosis is based on a steady increase in intrathecal morphine dosage after a relatively prolonged period of stability, on the gradual development of neurologic signs and symptoms suggesting radicular or spinal cord compression, and on magnetic resonance images. We describe a man with central neuropathic pain after removal of a tumor. The presence of all 3 of the aforementioned diagnostic criteria led to suspicion of a spinal granuloma.

Attitudes and Beliefs Regarding the Role of Interventional Pain Management at the End-of-Life Among Caregivers: A 4-Year Perspective

Intrathecal and epidural opioid analgesia represents a major advance in the management of cancer pain, adding a new dimension to opioid therapy by allowing prolonged analgesia through the use of significantly lower doses than those required for systemic administration. However, myths, misconceptions, and apprehension continue to serve as major barriers to effective cancer pain management, and concerns regarding safety, efficacy, and relative ease of utilization still prevail. This, in turn, results in unnecessary suffering, depression, diminished cognitive function, sleep disturbance, functional disability, and compromised quality of life. We conducted a survey to systematically explore medical and paramedical attitudes prior to and 4 years after the introduction an interventional pain program and attempted to qualitatively analyze what appeared as main facilities or difficulties following end-of-life clinical experiences. In general we found that all caregivers were satisfied from using interventional pain relief techniques at the end-of-life; more so among caregivers directly involved in patient care. Although nearly half of the responders initially found "technical manipulations" moderately difficult to difficult, after a simple hands-on instruction all found these techniques to be "helpful, simple and feasible." "When all went well," caregivers found implantable devices as a useful tool to relieve pain, to increase the ability of patients to complete personal endeavors, notably mobilization, but also noted an increased patient anxiety at the end-of-life. "When all went wrong," caregivers evoked the paradoxical attitude of patients to having a "high-tech" treatment at the end-of-life, causing them eventually to have "false hope," as well as the phenomenon of "interdisciplinary hyperactivity," creating what was referred to as therapeutic futility. In summary, this study suggests the importance on insisting to introduce novel techniques into practice despite initial apprehension, however, quality improvement by detecting and overcoming attitudinal barriers remain primordial and requires narrative research.

Fever of unknown origin, infection of subcutaneous devices, brain abscesses and endocarditis

The term 'fever of unknown origin' includes a wide range of conditions that often remain undiagnosed. The possibility of an infection must be promptly diagnosed in order to begin appropriate therapy. Imaging with radiopharmaceuticals, computed tomography, magnetic resonance imaging and ultrasound are the most commonly applied techniques, usually performed in addition to blood tests, biopsies or tissue cultures when required. The lack of comparative studies investigating the accuracy of each radiopharmaceutical for the study of fever of unknown origin was the incentive to perform a meta-analysis of peer articles published between 1981 and 2004 (33 papers) describing the use of nuclear medicine imaging for this purpose. Furthermore, infection of subcutaneous devices, brain abscesses and endocarditis must be considered amongst the causes of fevers of unknown origin. Reviews of 23, 10 and 10 papers, respectively (from 1976 to 2005), were performed on these specific topics. The results may be a useful guide for the choice of the optimal radiopharmaceutical(s) and diagnostic strategy to be applied in each clinical condition and for different aims.

Drug Delivery Systems

Intrathecal drug delivery (IDD) is a proven and effective treatment alternative in carefully selected patients with chronic pain that cannot be controlled by a well-tailored drug regime and/or spinal cord stimulation (SCS), and may be specifically trialed in patients who fail to respond to SCS. While the lack of randomized controlled trials is often perceived as a limitation of IDD, many studies attest to the efficacy of this therapy, and a number are large-scale and with follow-up periods of up to five years. Good to excellent pain relief is achieved in many patients who have failed more conservative therapies, and there is often a reduced need for analgesia. The advent of patient-controlled analgesia allows flexibility of dosing according to the patient's needs. Consequently, quality of life improves in many patients and the majority express satisfaction with treatment. Some patients are able to return to work. The benefits of IDD (including a potent analgesic response with a more stable therapeutic drug level, decreased latency, increased duration of action, and decreased pharmacological complications) mean that side effects such as nausea, vomiting, sedation, and constipation are reduced. In addition, IDD demonstrates long-term cost-effectiveness when compared to conventional pain therapies, addressing a concern that affects many physicians in clinical practice today.

Intraparenchymal migration of an intrathecal catheter three years after implantation

Intrathecal drug administration using implanted catheter and pump systems has been used in routine clinical practice for more than 20 years to treat chronic refractory pain or spasticity. Complications associated with the use of these systems include drug related adverse events as well as technical problems, most of which are related either to the catheter or the procedure. Although traumatic neural damage is exceedingly rare it is usually associated with significant neurological impairment. We present a case of asymptomatic intraspinal migration of an intrathecal catheter three years after an uneventful implantation. To the best of our knowledge, this complication has never been reported before.

Implantable devices for pain control: spinal cord stimulation and intrathecal therapies

Untreated chronic pain is costly to society and to the individual suffering from it. The treatment of chronic pain, a multidimensional disease, should rely on the expertise of varying health care providers and should focus not only on the neurobiological mechanisms of the process but also on the psychosocial aspects of the disease. Implantable devices are costly and invasive, and such efficacious therapies should be used only when more conservative and less costly therapies have failed to provide relief of pain and suffering. Spinal cord stimulation provides neuromodulation of neuropathic, but not nociceptive, pain signals and when used for appropriate indications in the right individuals provides approximately 60-80% long-term pain relief in 60-80% of patients trialled for efficacy. Intrathecal therapies with opioids such as morphine, fentanyl, sufentanil or meperidine--or non-opioids such as clonidine or bupivacaine--provide analgesia in patients with nociceptive or neuropathic pain syndromes. Baclofen, intrathecally, provides profound relief of muscle spasticity due to multiple sclerosis, spinal cord injuries, brain injuries or cerebral palsy.

The use of epidural and intrathecal analgesia in palliative care

Oral analgesics and adjunctive medicines will be used to meet the needs of most palliative care patients in terms of pain relief. However, for a small number of patients, this will not be adequate for satisfactory relief from pain, resulting in a lower quality of life. For such patients, using some of the more 'technical approaches' to pain relief, e.g. epidural or intrathecal analgesia, can prove beneficial. Taking the anatomy of the spinal space into consideration, this article will present the indications and contraindications for spinal analgesia, as well as drugs used and the most appropriate methods of drug administration.