Differential epidural block predicts the success of visceral block in patients with chronic visceral abdominal pain

BurstDR spinal cord stimulation in the treatment of chronic visceral pain

Background:Visceral pain can be disabling for patients and challenging to treat in the clinic. Spinal cord stimulation is a NICE approved treatment for chronic neuropathic pain, presenting potential advantages over conventional therapies for managing chronic visceral pain. Results: A retrospective study revealed that a specific type of spinal cord stimulation, BurstDR^TM (Abbott, TX, USA), was effective at improving pain and quality of life in patients with chronic visceral pain. Baseline pain scores significantly correlated with change at follow-up, suggesting it may be possible to identify potential responders from the outset. BurstDR was safe: rates of revision, explantation and complications were low. Conclusion: Clinical trials exploring the long-term effects of BurstDR including a control arm are needed. Findings could have the potential to inform best practice and improve outcomes for individuals with chronic visceral pain.

Interventional Pain Management Approaches for Control of Chronic Pancreatic Pain

OPINION STATEMENT

Treatment of persistent pain from chronic pancreatitis historically was difficult to treat. For years, focus was on opioid and other analgesics and psychological treatments. Recent studies provided evidence for decrease in analgesic intake and pain scores after properly conducted sympathetic blocks (celiac, splanchnic nerve blocks). These therapies should be considered as parts of a multimodal analgesic strategy. Animal studies suggest that spinal cord stimulation suppresses visceral hyperalgesia. Large case series of spinal cord stimulation demonstrated a significant pain relief in patients with chronic pancreatitis. Given the limitations of conservative and surgical treatments for chronic visceral pain, spinal cord stimulation may be a very useful therapeutic option.

The appropriate use of neurostimulation of the spinal cord and peripheral nervous system for the treatment of chronic pain and ischemic diseases: the Neuromodulation Appropriateness Consensus Committee

INTRODUCTION

The Neuromodulation Appropriateness Consensus Committee (NACC) of the International Neuromodulation Society (INS) evaluated evidence regarding the safety and efficacy of neurostimulation to treat chronic pain, chronic critical limb ischemia, and refractory angina and recommended appropriate clinical applications.

METHODS

The NACC used literature reviews, expert opinion, clinical experience, and individual research. Authors consulted the Practice Parameters for the Use of Spinal Cord Stimulation in the Treatment of Neuropathic Pain (2006), systematic reviews (1984 to 2013), and prospective and randomized controlled trials (2005 to 2013) identified through PubMed, EMBASE, and Google Scholar.

RESULTS

Neurostimulation is relatively safe because of its minimally invasive and reversible characteristics. Comparison with medical management is difficult, as patients considered for neurostimulation have failed conservative management. Unlike alternative therapies, neurostimulation is not associated with medication-related side effects and has enduring effect. Device-related complications are not uncommon; however, the incidence is becoming less frequent as technology progresses and surgical skills improve. Randomized controlled studies support the efficacy of spinal cord stimulation in treating failed back surgery syndrome and complex regional pain syndrome. Similar studies of neurostimulation for peripheral neuropathic pain, postamputation pain, postherpetic neuralgia, and other causes of nerve injury are needed. International guidelines recommend spinal cord stimulation to treat refractory angina; other indications, such as congestive heart failure, are being investigated.

CONCLUSIONS

Appropriate neurostimulation is safe and effective in some chronic pain conditions. Technological refinements and clinical evidence will continue to expand its use. The NACC seeks to facilitate the efficacy and safety of neurostimulation.

Chronic pancreatitis pain pattern and severity are independent of abdominal imaging findings

BACKGROUND & AIMS

Chronic pancreatitis is characterized by inflammation, atrophy, fibrosis with progressive ductal changes, and functional changes that include variable exocrine and endocrine insufficiency and multiple patterns of pain. We investigated whether abdominal imaging features accurately predict patterns of pain.

METHODS

We collected data from participants in the North American Pancreatitis Study 2 Continuation and Validation, a prospective multicenter study of patients with chronic pancreatitis performed at 13 expert centers in the United States from July 2008 through March 2012. Chronic pancreatitis was defined based on the detection of characteristic changes by cross-sectional abdominal imaging, endoscopic retrograde cholangiopancreatography, endoscopic ultrasonography, or histology analyses. Patients were asked by a physician or trained clinical research coordinator if they had any abdominal pain during the year before enrollment, those who responded "yes" were asked to select from a list of 5 pain patterns. By using these patterns, we classified patients' pain based on timing and severity. Abnormal pancreatitis-associated features on abdominal imaging were recorded using standardized case report forms.

RESULTS

Data were collected from 518 patients (mean age, 52 ± 14.6 y; 55% male; and 87.6% white). The most common physician-identified etiologies were alcohol (45.8%) and idiopathic (24.3%); 15.6% of patients reported no abdominal pain in the year before enrollment. The most common individual pain pattern was described as constant mild pain with episodes of severe pain and was reported in 45% of patients. The most common imaging findings included pancreatic ductal dilatation (68%), atrophy (57%), and calcifications (55%). Imaging findings were categorized as obstructive for 20% and as inflammatory for 25% of cases. The distribution of individual imaging findings was similar among patients with different patterns of pain. The distribution of pain patterns did not differ among clinically relevant groups of imaging findings.

CONCLUSIONS

Mechanisms that determine patterns and severity of pain in patients with chronic pancreatitis are largely independent of structural variants observed by abdominal imaging techniques. Pancreas-relevant quantitative and qualitative pain measures should be included in the evaluation of patients with chronic pancreatitis to assess pain severity independently of imaging findings.

Spinal cord stimulation for visceral pain from chronic pancreatitis

BACKGROUND AND OBJECTIVES

  Spinal cord stimulation (SCS) may reduce pain scores and improve function in patients with various chronic abdominal pain syndromes including chronic pancreatitis. Here described is a large clinical experience in SCS for severe chronic pancreatitis.

METHODS

  SCS was trialed in 30 patients with chronic pancreatitis. SCS trials lasted 7-14 days (median 9 days). SCS lead tips were mostly positioned at the T5 (N= 10) or T6 (N= 10) vertebral level.

RESULTS

  Twenty-four patients (80%) reported at least 50% pain relief on completion of the trial. Among these, pre-trial visual analog scale (VAS) pain scores averaged 8 ± 1.6 (standard deviation) and opioid use averaged 165 ± 120 mg morphine sulfate equivalents. During the trial, VAS pain scores decreased to 3.67 ± 2 cm (p < 0.001, Mann-Whitney Rank Sum Test) and opioid use decreased to 105 ± 101 mg morphine equivalent a day. Six patients failed the trial; one was lost to follow-up; in three patients after the implantation, the system had to be removed due to infection or lead migration; and 20 were followed for the whole year. For 20 patients followed for the whole year, VAS pain scores remained low (3.6 ± 2 cm; p < 0.001) at one year, as did opioid use (48.6 ± 58 mg morphine equivalents).

CONCLUSIONS

  SCS may be a useful therapeutic option for patients with severe visceral pain from chronic pancreatitis. Prospective trial is warranted.