16. Complex Regional Pain Syndrome

Complex regional pain syndrome (CRPS), formerly known as reflex sympathetic dystrophy is a pain syndrome with an unclear pathophysiology and unpredictable clinical course. The disease is often therapy resistant, the natural course not always favorable. The diagnosis of CRPS is based on signs and symptoms derived from medical history and physical examination. Pharmacological pain management and physical rehabilitation of limb function are the main pillars of therapy and should be started as early as possible. If, however, there is no improvement of limb function and persistent severe pain, interventional pain management techniques may be considered. Intravenous regional blocks with guanethidine did not prove superior to placebo but frequent side effects occurred.Therefore this technique receives a negative recommendation (2 A–). Sympathetic block is the interventional treatment of first choice and has a 2 B+ rating. Ganglion stellatum (stellate ganglion) block with repeated local anesthetic injections or by radiofrequency denervation after positive diagnostic block is documented in prospective and retrospective trials in patients suffering from upper limb CRPS. Lumbar sympathetic blocks can be performed with repeated local anesthetic injections. For a more prolonged lumbar sympathetic block radiofrequency treatment is preferred over phenol neurolysis because effects are comparable whereas the risk for side effects is lower (2 B+). For patients suffering from CRPS refractory to conventional treatment and sympathetic blocks, plexus brachialis block or continuous epidural infusion analgesia coupled with exercise therapy may be tried (2 C+). Spinal cord stimulation is recommended if other treatments fail to improve pain and dysfunction (2 B+). Alternatively peripheral nerve stimulation can be considered, preferentially in study conditions (2 C+).     

Complex regional pain syndrome involving the lower extremity: a report of 2 cases of sphenopalatine block as a treatment option

We report 2 cases of complex regional pain syndrome (CRPS) involving the lower extremity; in both, a sphenopalatine ganglion (SPG) block was performed as part of a pain management program. In the first case, a woman in her late twenties presented with CRPS in the left lower extremity that was inadequately controlled with typical oral medications. Sympathetic block of the extremity did not provide significant pain relief. However, a noninvasive sphenopalatine block with 4% tetracaine resulted in a 50% reduction in pain level. The patient was shown how to self-administer the sphenopalatine block and was provided with exercises and therapy to help improve her functional status. The second case involved a woman in her mid forties with CRPS in the right lower extremity that was partially controlled with oral medications. The patient experienced a 50% reduction in pain level when SPG block with 4% tetracaine was given. Further study is needed to determine the effects of SPG blocks on symptoms related to chronic regional pain syndrome.     

Complete Recovery From Intractable Complex Regional Pain Syndrome, CRPS-Type I, Following Anesthetic Ketamine and Midazolam

Objective: To describe the treatment of an intractable complex regional pain syndrome I (CRPS-I) patient with anesthetic doses of ketamine supplemented with midazolam.
Methods: A patient presented with a rapidly progressing contiguous spread of CRPS from a severe ligamentous wrist injury. Standard pharmacological and interventional therapy successively failed to halt the spread of CRPS from the wrist to the entire right arm. Her pain was unmanageable with all standard therapy. As a last treatment option, the patient was transferred to the intensive care unit and treated on a compassionate care basis with anesthetic doses of ketamine in gradually increasing (3–5 mg/kg/h) doses in conjunction with midazolam over a period of 5 days.
Results: On the second day of the ketamine and midazolam infusion, edema, and discoloration began to resolve and increased spontaneous movement was noted. On day 6, symptoms completely resolved and infusions were tapered. The patient emerged from anesthesia completely free of pain and associated CRPS signs and symptoms. The patient has maintained this complete remission from CRPS for 8 years now.
Conclusions: In a patient with severe spreading and refractory CRPS, a complete and long-term remission from CRPS has been obtained utilizing ketamine and midazolam in anesthetic doses. This intensive care procedure has very serious risks but no severe complications occurred. The psychiatric side effects of ketamine were successfully managed with the concomitant use of midazolam and resolved within 1 month of treatment.
This case report illustrates the effectiveness and safety of high-dose ketamine in a patient with generalized, refractory CRPS.     

Intravenous regional block with lidocaine for treatment of complex regional pain syndrome

OBJECTIVES: The goal of this article is to report the successful treatment of a patient with complex regional pain syndrome (CRPS) type 1 involving the hand with the use of an intravenous regional block. METHODS: The patient was a 35-year-old woman who developed CRPS during conservative therapy for a metacarpal fracture. An intravenous regional block with lidocaine alone, using a two-tourniquet technique, was delivered 10 times for at least 40 minutes. The first five treatments were given twice a week and the next five were delivered weekly. All affected joints, including the wrist, were manipulated without undue force. Functional physical measurements were assessed, including range of motion and performance of fine and gross motor tasks. RESULTS: The visual analog scale scores for pain declined from 10 to 0 after treatment. Use of a pen, a pair of chopsticks, and a hammer improved, and edema decreased. CONCLUSIONS: Intravenous regional block with lidocaine was well tolerated and associated with relief in this case of CRPS type 1.     

Ultrasound‐Guided Continuous Superficial Peroneal Nerve Block below the Knee for the Treatment of Nerve Injury

(CRPS) describes a constellation of symptoms including pain, trophic changes, hyperesthesia, allodynia, and dysregulation of local blood flow often following trauma. It is often confined to the extremities. Treatment of this disorder consists of a variety of modalities including systemic pharmacotherapy, local anesthetic injections or infusions, psychological nonpharmacotherapy, physical rehabilitation, and surgical intervention. Chronic pain not related to CRPS can also be treated with similar interventions. Despite the array of available therapies, it can still be difficult to manage. We report a case of a 19‐year‐old patient diagnosed by her surgeon as having CRPS Type II, secondary to foot trauma, which was treated with a continuous infusion of local anesthetic at the superficial peroneal nerve (SPN). While placement of peripheral nerve block catheters to augment chronic pain therapy is not novel, the application of a perineural catheter at the SPN has not been previously described.     

Computed tomography guided lumbar sympathetic block for complex regional pain syndrome in a child: a case report and review.

The aim of this paper is to describe the first reported use of computed tomography (CT) guided lumbar sympathetic block as treatment of a case of complex regional pain syndrome (CRPS) in a child. The potential aetiology of CRPS is discussed in relation to the mechanism of action of local anaesthetics used in the block. Based on the successful treatment of this child and the documented success of its use in adults, we conclude that despite the minimal dose of radiation given, CT guided lumbar sympathetic block is an important treatment option in CRPS in children.     

MULTIDISCIPLINARY PAIN ABSTRACTS: 34

Because recent studies emphasized the role of peripherally distributed N-methyl-D-aspartate (NMDA) receptors in processing the nociceptive information, the authors investigated whether peripheral application of the ointment containing ketoconazole (KET) is able to attenuate the symptoms of local neuropathic pain. They applied ointment containing KET (0.25%–1.5%) to the affected area on limbs in five patients with complex regional pain syndrome type I (CRPS I) and in two patients with type II (CRPS II). One to 2 weeks later, they observed improvement of the report of pain intensity, measured by the visual analog scale, in four patients with acute early dystrophic stage of CRPS I. Swelling of the affected limbs subsided as well. No apparent changes were noticed in one patient with chronic atrophic stage of CRPS I and in both patients with CRPS II. The authors concluded that topical application of KET appears to be beneficial for the patients with acute early dystrophic stage of CRPS I because of either its local anesthetic effect or NMDA receptor antagonist action. Patients with chronic atrophic stage of CRPS I and CRPS II patients do not appear to respond to this treatment.     

Complex regional pain syndrome (type I) after electrical injury: a case report of treatment with continuous epidural block.

A 26-year-old man presented with severe complex regional pain syndrome type I of the affected limb after a work-related electrical injury. He suffered causalgia-like pain with no electrodiagnostic evidence of nerve injury. Early steroid and analgesic regimens did not adequately relieve these symptoms. His symptoms were temporarily relieved several times with stellate ganglion blocks. The patient underwent a cervical epidural block with a local anesthetic as well as a narcotic agonist over a 4-day period, which resulted in prompt, remarkable pain relief. Vocational rehabilitation was instituted as the pain subsided.     

Axillary brachial plexus block with patient controlled analgesia for complex regional pain syndrome type I: a case report. (National Cheng Kung University, Tainan, Taiwan) Reg Anesth Pain Med 2001;26:68–71.

A 32-year-old man who suffered from complex regional pain syndrome type I (CRPS I) of the right upper limb after surgical release of carpal tunnel syndrome of the right hand is the subject of this case report. Symptoms and signs over the right hand were alleviated under rehabilitation and conventional pharmacological management, but severe painful swelling of the right wrist persisted. Axillary brachial plexus block (BPB) with patient controlled analgesia (PCA) was performed on the 32^nd postoperative day, which soon resulted in significant reduction of pain with gradual improvement of function of the right wrist. Conclude that axillary BPB with PCA may provide patients with CRPS I of the upper limb a feasible and effective treatment.     

Failure of epidural opioid to control cancer pain in a patient previously treated with massive doses of intravenous opioid

A patient with disseminated cancer pain failed to obtain pain relief despite the intravenous infusion of hydromorphone at a rate equivalent to over 7 g of morphine/day. Temporary pain relief occurred with an epidural injection of the local anesthetic lidocaine. Subsequently, the patient failed to obtain pain relief with a dose of epidural hydromorphone equivalent to approximately 3 g of morphine epidurally/day. At this time a syndrome of agitation, sweating, tachycardia and severe muscle cramps developed in the lower half of the body. After eliminating the possibility of spinal cord compression by diagnostic CT scanning, the patient was treated by reducing the dose of hydromorphone and adding local anesthetic, which provided pain relief but did not eliminate the severe muscle spasms and other symptoms. The addition of oral clonidine followed by clonidine dermal patch rapidly and completely eliminated the other symptoms, suggesting that the response was due to too rapid withdrawal of opioid. Maintenance of pain relief required the simultaneous administration of epidural bupivacaine and hydromorphone. A low-dose infusion of epidural bupivacaine was continued for more than 3 weeks and during this entire period the patient showed no evidence of motor or sympathetic block.     

Defining the therapeutic role of local anesthetic sympathetic blockade in complex regional pain syndrome: a narrative and systematic review

OBJECTIVE: There is growing controversy on the value of blocking the sympathetic nervous system for the treatment of complex regional pain syndromes (CRPS). The authors sought to evaluate the efficacy of sympathetic blockade with local anesthetic in these syndromes. In addition, they performed a comprehensive review of the pathophysiology and other treatments for CRPS. DESIGN: Systematic review of the literature was performed. MEDLINE was searched from 1966 through 1999. The authors identified only three randomized controlled trials (RCTs) that evaluated sympathetic blockade with local anesthetic, but because of differences in study design they were unable to pool the study data. The authors therefore included nonrandomized studies and case series. INTERVENTIONS: Studies were included if local anesthetic sympathetic blockade was used in at least 10 patients. Studies were excluded if continuous infusion techniques, somatic nerve blocks, or combined sympatholytic therapies were evaluated. OUTCOME MEASURES: Pain relief was classified as full, partial, or absent. The lack of a comparison group in the studies allowed only the calculation of distribution of the response categories, and the sum of the pooled rates does not equal 100%. RESULTS: Twenty-nine studies were included that evaluated 1,144 patients. Nineteen studies were retrospective, 5 prospective case series, 3 RCTs, and 2 nonrandomized controlled studies. The quality of the publications was generally poor. Twenty-nine percent of patients had full response, 41% had partial response, and 32% had absent response. It was not possible to estimate the duration of pain relief. CONCLUSIONS: This review raises questions as to the efficacy of local anesthetic sympathetic blockade as treatment of CRPS. Its efficacy is based mainly on case series. Less than one third of patients obtained full pain relief. The absence of control groups in case series leads to an overestimation of the treatment response that can explain the findings.     

Complex regional pain syndrome as a complication of a chemical burn to the foot

Complex regional pain syndrome (CRPS) is an unusual complication after burns; however, it is important to recognize so that appropriate treatment can be administered. A 60-year-old man suffered an alkali burn to the right foot. Subsequently, the patient developed CRPS with severe pain and vasomotor changes. Multimodal treatment included the early use of ropivacaine and fentanyl via epidural catheter. Oral extended-release morphine, gabapentin, and amitriptyline also were administered. Once pain was controlled, early aggressive physical therapy was instituted, and attention was turned toward wound coverage. One year after discharge, the patient was ambulating well and has returned to work. His pain was managed with a single morning dose of gabapentin and a nonsteroidal anti-inflammatory agent. Current examination of the foot revealed mild forefoot swelling without residual erythema. Ambiguities exist in the mainstay of treatment for CRPS, but this multimodal method of controlling CRPS after burn injury allowed for control of the patient's pain, early mobilization, and eventual return to work.     

Labor analgesia

Regional analgesia has become the most common method of pain relief used during labor in the United States. Epidural and spinal analgesia are two types of regional analgesia. With epidural analgesia, an indwelling catheter is directed into the epidural space, and the patient receives a continuous infusion or multiple injections of local anesthetic. Spinal injections are usually single injections into the intrathecal space. A combination of epidural and spinal analgesia, known as a walking epidural, also is available. This technique combines the rapid pain relief from the spinal regional block with the constant and consistent effects from the epidural block. It allows sufficient motor function for patients to ambulate. Complications with regional analgesia are uncommon, but may include postdural puncture headache. Rare serious complications include neurologic injury, epidural hematoma, or deep epidural infection. Regional analgesia increases the risk of instrument-assisted vaginal delivery, and family physicians should understand the contraindications and risks of complications. Continuous labor support (e.g., doula), systemic opioid analgesia, pudendal blocks, water immersion, sterile water injections into the lumbosacral spine, self-taught hypnosis, and acupuncture are other options for pain management during labor.     

A case of pain,motor impairment,and swelling of the arm after acute herpes zoster infection

Complex regional pain syndrome (CRPS) and postherpetic neuralgia (PHN) represent neuropathic pain syndromes that may appear with similar clinical signs and symptoms. Medical history and clinical distribution of symptoms and signs (PHN typically at the thorax; CRPS typically at the limbs) is obvious in most cases, helping to discriminate between both disorders. Here, we present a patient suffering from CRPS II following PHN of one upper extremity. This case demonstrates that both etiology and part of the body affected by a neuropathy influence the pain phenotype.     

Complex regional pain syndrome

Complex regional pain syndrome (CRPS), formerly known as reflex sympathetic dystrophy, is a regional, posttraumatic, neuropathic pain problem that most often affects 1 or more limbs. Like most medical conditions, early diagnosis and treatment increase the likelihood of a successful outcome. Accordingly, patients with clinical signs and symptoms of CRPS after an injury should be referred immediately to a physician with expertise in evaluating and treating this condition. Physical therapy is the cornerstone and first-line treatment for CRPS. Mild cases respond to physical therapy and physical modalities. Mild to moderate cases may require adjuvant analgesics, such as anticonvulsants and/or antidepressants. An opioid should be added to the treatment regimen if these medications do not provide sufficient analgesia to allow the patient to participate in physical therapy. Patients with moderate to severe pain and/or sympathetic dysfunction require regional anesthetic blockade to participate in physical therapy. A small percentage of patients develop refractory, chronic pain and require long-term multidisciplinary treatment, including physical therapy, psychological support, and pain-relieving measures. Pain-relieving measures include medications, sympathetic/somatic blockade, spinal cord stimulation, and spinal analgesia.     

Pharmacologic treatment of complex regional pain syndrome I: a conceptual framework

Pain may be a leading symptom in complex regional pain syndrome type I (CRPS I) and may hinder functional recovery. In this case, a pharmacotherapeutic approach to pain should be part of the individually tailored interdisciplinary treatment regimen. However, operational criteria for determining which patient may profit from what therapeutic intervention are lacking. This article discusses a conceptual framework in which the rapid progress made in basic pain research may contribute to the clinical management of pain in CRPS I. First, recent insights in the pathophysiologic mechanisms underlying CRPS I are reviewed. CRPS I is considered a neuropathic pain syndrome with a mixed and time-dependent profile of a regional inflammation, sensitization of primary somatosensory afferents (peripheral sensitization), and sensitization of spinal neurons (central sensitization). The dominant mechanisms may vary across individual patients with different time profiles. Second, a model was constructed in which signs and symptoms in an individual patient are related to these mechanisms. Finally, relating the clinical picture to the underlying pathophysiology may help determine the pharmacotherapeutic approach for an individual patient. Pharmacologic options are discussed in this context. The presented framework does not aim to provide an evidence-based treatment algorithm, ready to be used in daily clinical practice; rather it offers a crude, first step toward a mechanism-based pharmacotherapy in CRPS I, in an effort to shift from a mainly empirical treatment paradigm toward theory-driven treatment procedures.     

Bier block as a successful management of a patient with intractable complex regional pain syndrome (CRPS) type 1: A case report

Bier block was successful in the pain management of complex regional pain syndrome (CRPS) type 1.     

Ultrasound‐Guided Transversus Abdominis Plane Catheter for Chronic Abdominal Pain

Abstract Background and Objectives: Neural blockade of the thoracolumbar nerves supplying the anterior abdominal wall through transversus abdominis plane (TAP) has been investigated for different applications mainly for the acute pain management following abdominal surgical procedures. The role of this block for chronic pain syndromes is still to be discovered, and its value in chronic abdominal pain needs to be studied. We are presenting new application of the TAP technique for management of chronic abdominal pain syndrome using the continuous infusion. Case report: We present a case of an 18‐year‐old girl who underwent an uneventful laparoscopic cholecystectomy. Postoperatively, patient complained of chronic pain at the site of the surgery. All diagnostic and imaging studies were negative for a surgical or a medical cause. Multiple interventions including epidural blocks, transcutaneous electrical neural stimulation, and celiac plexus blocks had failed to relieve the pain. After discussion with the patient about the diagnostic nature of the procedure and the likelihood of recurrence of pain, TAP block was performed on the right side with significant improvement of pain for about 24 hours. The degree of pain relief experienced by the patient was very dramatic, which encouraged us to proceed with an indwelling TAP catheter to allow for continuous infusion of a local anesthetic. The patient was sent home with the continuous infusion through a TAP catheter for 2 weeks. From the day of catheter insertion and up to 9 months of follow‐up, patient had marked improvement of her pain level as well as her functional status and ability to perform her daily activities, after which our acute pain team stopped following the patient. Conclusion: A successful TAP block confirmed the peripheral (somatic) source of the abdominal pain and provided temporary analgesia after which an indwelling catheter was inserted, which provided prolonged pain relief.     

Epidural unilateral stimulation with “adaptive stim” option in treatment of type II CRPS

CRPS is a type of severe pain syndrome and can be triggered by previous surgery or trauma. CRPS involves vasomotor changes such as changes in color and temperature of the skin, edema, increased sensitivity to touch, and a limited range of movement. Depending on the presence of nerve damage, CRPS is divided into two types. CRPS type II is associated with a confirmed peripheral nerve injury, while CRPS type I is not associated with an apparent peripheral nerve injury. Despite the ongoing therapy, sometimes, patients still have persistent, burning pain. Intractable CRPS that fail more conservative treatments may undergo neuromodulation. We want to present to your attention a case report of the successful treatment of a patient with CRPS type II using epidural unilateral stimulation. The 44‐year‐old woman came to us with complaints of burning pain and numbness of 1–3 fingers of the right hand, the lateral surface of the right wrist, and lower quarter of the forearm, and shooting pain in the projection of the right median nerve from the shoulder to the wrist. A clinical diagnosis was made—CRPS type II. During the stimulation trial, the most effective pain relief was obtained when the electrode was located in the right side of epidural space at the C4‐Th1 level. The implantation of a pulse generator was performed, and the final selection of the stimulation parameters was carried out (Pulse width: 60 ms, Rate: 210 Hz, and Amplitude: 0.9–1.6 V). The severity of pain syndrome was measured using validated scales in the preoperative period (VAS: 8–9, Pain Detect: 22, NTSS‐9: 4.62, and DN4: 8), in the early postoperative period (VAS: 0–1, Pain Detect: 6, NTSS −9: 0.66, and DN4: 1), and after 12 months (VAS: 0–2, Pain Detect: 6, NTSS‐9: 0.99, and DN4: 1). Observation during 12 months showed that a stable analgesic effect of neurostimulation was achieved using standard neuromodulation regimens and the adaptive stim option. Unilateral stimulation is an effective type of SCS in the treatment of pain syndromes. adaptive stim is usually not applicable for lead implantation at the cervical level. Nevertheless, the rational use of stimulation at threshold values allowed our patient to use adaptive stim in a non‐standard situation.