R.T.M. van Dongen

Intrathecal coadministration of bupivacaine diminishes morphine dose progression during long-term intrathecal infusion in cancer patients.

OBJECTIVE To determine the difference in intrathecal morphine dose progression between a continuous intrathecal infusion of a morphine/bupivacaine mixture and morphine for pain relief in patients with cancer. DESIGN Patients were treated with intrathecal drugs in a randomized study and followed prospectively until death. SETTING Institute for Anesthesiology, Department of Pain Treatment, University Hospital Nijmegen, St Radboud, The Netherlands. PATIENTS Twenty patients with cancer were selected for intrathecal treatment because of either side effects or inadequate relief during conventional pain treatment. INTERVENTIONS Intrathecal drug infusion rates and medication were adjusted according to pain relief and side effects. OUTCOME MEASURES Progression of intrathecal morphine dose during a phase of adequate analgesia in both groups following regression analysis and analysis of possible treatment related side effects. RESULTS The combination of intrathecal morphine and bupivacaine resulted in a diminished progression of the intrathecal morphine dose (slope of regression line = 0.0003 vs. 0.005, p = 0.0001) during a phase of stable analgesia in comparison with the morphine group. No serious side effects presented. CONCLUSION The diminished intrathecal morphine dose increase in the combination group is considered to be due to a synergistic effect of bupivacaine on the intrathecal morphine-induced antinociception. A dose increment during long-term intrathecal infusion in cancer patients appears to be related to both disease progression and tolerance phenomena.

The present role of percutaneous cervical cordotomy for the treatment of cancer pain

The results obtained by percutaneous cervical cordotomy (PCC) were analysed in 43 terminally ill cancer patients treated in our institution from 1998 to 2001. We wished to determine whether there is still a place for PCC in the actual clinical situation with its wide choice of pain therapies. All patients had severe unilateral pain due to cancer, resistant to opioids and co–analgesics. Following PCC, mean pain intensity was reduced from Numeric Rating Scale (NRS) 7.2 to 1.1. At the end of life, pain had increased to NRS 2.9. Initially following PCC a good result (NRS<3) was obtained in 95% of patients. At the end of life, a good result was still present in 69% of patients. Mean duration of survival after the intervention was 118 days (2–1460). In general, complications were mild and mostly subsided within 3–4 days. There was one case of partial paresis of the ipsilateral leg. PCC remains a valuable treatment in patients with treatment–resistant cancer pain and still deserves a place in the treatment of terminal cancer patients with severe unilateral neuropathic or incidence pain.

Pain exposure physical therapy may be a safe and effective treatment for longstanding complex regional pain syndrome type 1: a case series:

Objective: To determine if treatment of longstanding complex regional pain syndrome type 1, focusing on functional improvement only while neglecting pain, results in clinical improvement of this syndrome. Design: Prospective description of a case series of 106 patients. Setting: Outpatient clinic for rehabilitation. Interventions: Physical therapy of the affected limb directed at a functional improvement only while neglecting the pain, was performed following an extensive explanation. Normal use of the limb between the treatments was encouraged despite pain. A maximum of five of these sessions were performed in three months. Measures: Radboud Skills Test was used to monitor functional improvement of the arms. Speed and walking distance was used as the measure of outcome for the legs. Results: The function of the affected arm or leg improved in 95 patients. Full functional recovery was experienced in 49 (46%) of them. A reduction in pain presented in 75 patients. In 23 patients functional recovery was reached despite an increase in pain. Four patients stopped early due to pain increase. Conclusions: Our results suggest that ‘pain exposure physical therapy’ is effective and safe for patients who are unresponsive to accepted standard therapies. Avoiding the use of a limb due to pain will result in loss of function. Forced usage of limbs restores the function, reverses these adaptive processes and leads to regain of control by practice with a reduction of pain in most cases.

Spinal Cord Stimulation and Pain Relief in Painful Diabetic Peripheral Neuropathy: A Prospective Two-Center Randomized Controlled Trial

OBJECTIVE Painful diabetic peripheral neuropathy (PDPN) is a common complication of diabetes mellitus. Unfortunately, pharmacological treatment is often partially effective or accompanied by unacceptable side effects, and new treatments are urgently needed. Small observational studies suggested that spinal cord stimulation (SCS) may have positive effects. RESEARCH DESIGN AND METHODS We performed a multicenter randomized clinical trial in 36 PDPN patients with severe lower limb pain not responding to conventional therapy. Twenty-two patients were randomly assigned to SCS in combination with the best medical treatment (BMT) (SCS group) and 14 to BMT only (BMT group). The SCS system was implanted only if trial stimulation was successful. Treatment success was defined as ≥50% pain relief during daytime or nighttime or “(very) much improved” for pain and sleep on the patient global impression of change (PGIC) scale at 6 months. RESULTS Trial stimulation was successful in 77% of the SCS patients. Treatment success was observed in 59% of the SCS and in 7% of the BMT patients (P < 0.01). Pain relief during daytime and during nighttime was reported by 41 and 36% in the SCS group and 0 and 7% in the BMT group, respectively (P < 0.05). Pain and sleep were “(very) much improved” in 55 and 36% in the SCS group, whereas no changes were seen in the BMT group, respectively (P < 0.001 and P < 0.05). One SCS patient died because of a subdural hematoma. CONCLUSIONS Treatment success was shown in 59% of patients with PDPN who were treated with SCS over a 6-month period, although this treatment is not without risks.

Evidence-based interventional pain medicine according to clinical diagnoses. 18. Painful diabetic polyneuropathy.

In the industrialized world, polyneuropathy induced by diabetes mellitus (DM) is one of the most prevalent forms of neuropathy. Diabetic neuropathy can result from a direct toxic effect of glucose on nerve cells. Additionally, the damage of the nerve structures (central and peripheral) is accompanied by a microvascular dysfunction, which damages the vasa nervorum. More than 80% of the patients with DM‐induced polyneuropathy have a distal and symmetric presentation. The initial symptoms are: signs of diminished sensation, burning feet, which may occur particularly during the night and worsen when touched, and tingling sensation in the feet. Attacks of shooting pain may also occur.

Multidisciplinary Allocation of Pain Treatment: Long-Term Outcome and Correlates of Cognitive-Behavioral Processes

Objective: To investigate the long-term effects of multidisciplinary allocation of pain treatment on pain intensity, functional disability, depression, and medication use in outpatients with chronic pain, and to identify cognitive-behavioral predictors [worrying, avoidance behavior, fear of pain, helplessness, and acceptance] of the primary outcome measures. Methods: Eighty-six outpatients with chronic pain who were treated at a multidisciplinary pain center completed various questionnaires and a pain diary one week before treatment started, and 3 and 12 months later. Results: Functional disability and depression improved significantly 12 months after the start of treatment in comparison with before treatment. The decrease in scores for the cognitive-behavioral variables worrying, fear of pain, helplessness, and avoidance behavior at three months was associated with the decrease in functional disability and depression at 12 months. Conclusion: Patients with chronic pain may benefit in the long term from multidisciplinary allocation to pain treatment with respect to functional disability and depression. Changes of cognitive-behavioral processes seem to contribute to achieving long-term effects of multidisciplinary allocation of pain treatment. There is a need for high quality clinical trials in this field in order to clarify the specific contribution of cognitive-behavioral process variables.

Pain Exposure Physical Therapy versus conventional treatment in complex regional pain syndrome type 1—a cost-effectiveness analysis alongside a randomized controlled trial:

Objective: To analyze cost-effectiveness of Pain Exposure Physical Therapy compared to conventional treatment alongside a randomized controlled trial (NCT00817128) in patients with complex regional pain syndrome type 1, where no clinical difference was shown between the two groups in an intention-to-treat analysis. Design: Randomized controlled trial with 9 months follow-up. Setting: Patients were recruited from hospitals and general practitioners in the region around a university hospital. Subjects: A total of 56 patients, 45 (80.4%) female, were randomized. About 4 patients in the intervention and 11 patients in the conventional group switched groups. The mean (SD) age was 44.3 (16.6) years, and in 37 (66.1%) patients, the upper extremity was affected. Interventions: Patients received either Pain Exposure Physical Therapy (maximum of five sessions), or conventional treatment conforming with the Dutch multidisciplinary guideline. Main measures: For the economic evaluation difference between the groups in health-related quality of life (quality-adjusted life years (QALYs)), and the clinical outcomes Impairment level Sum Score—Restricted Version and Pain Disability was determined based on the intention-to-treat analysis as well as differences in both healthcare-related costs and travel expenses. Cost-effectiveness planes were constructed using bootstrapping to compare effects and costs. Results: No significant effects were found for QALYs (mean difference = −0.02; 95% confidence interval (CI) −0.10 to 0.04) and clinical outcomes. A cost minimization analysis showed a significant difference in costs between groups. The conventional treatment was 64% more expensive than the Pain Exposure Physical Therapy. Conclusion: This economic analysis shows that Pain Exposure Physical Therapy compared to conventional treatment is cost-effective.

Central neuropathic mechanisms in post-stroke shoulder pain

Central neuropathic pain mechanisms may play a larger role in chronic PSSP than is traditionally assumed. With the DN4, it is possible to select a subgroup of PSSP patients with more severe pain complaints and sensory abnormalities. Subgroup identification based on the DN4 might be used in future longitudinal and intervention studies to further explore the mechanisms underlying PSSP.

Long-term effect of motor cortex stimulation in patients suffering from chronic neuropathic pain: An observational study

Background Motor cortex stimulation (MCS) was introduced as a last-resort treatment for chronic neuropathic pain. Over the years, MCS has been used for the treatment of various pain syndromes but long-term follow-up is unknown. Methods This paper reports the results of MCS from 2005 until 2012 with a 3-year follow-up. Patients who suffered from chronic neuropathic pain treated with MCS were studied. The analgesic effect was determined as successful by decrease in pain-intensity on the visual analog scale (VAS) of at least 40%. The modifications in drug regimens were monitored with use of the medication quantification scale (MQS). Stimulation parameters and complications were also noted. Interference of pain with quality of life (QoL), the Quality of Life Index (QLI), was determined with use of a specific subset of questions from the MPQ-DLV score. Results Eighteen patients were included. Mean pre-operative VAS changed from 89.4 ± 11.2 to 53.1 ± 25.0 after three years of follow-up (P < 0.0001). A successful outcome was achieved in seven responders (38.9%). All patients in the responder group suffered from pain caused by a central lesion. With regard to all the patients with central pain lesions (n = 10) and peripheral lesions (n = 8), a significant difference in response to MCS was noticed (P = 0.002). MQS scores and QLI-scores diminished during the follow-up period (P = 0.210 and P = 0.007, respectively). Conclusion MCS seems a promising therapeutic option for patients with refractory pain syndromes of central origin.