CT-guided stellate ganglion blockade vs. radiofrequency neurolysis in the management of refractory type I complex regional pain syndrome of the upper limb

Sonographic imaging of the stellate ganglion in healthy adults: An observational study

The aim of this study is to estimate the normal cross-sectional area and diameter of the stellate ganglion (SG) by ultrasound (US) in healthy adults. The study sample included 80 stellate ganglia in 40 participants (15 males, 25 females), mean age 38 years, mean height 162.5 cm, mean weight 67.8 kg, mean body mass index 25.4 kg/m2. Two radiologists separately obtained US images of the bilateral SG. Each participant was scanned 3 times bilaterally to assess for intra-observer reliability. The mean diameter of the SG was 1 mm (range: 0.1-2). The mean CSA of the bilateral SG was 1.3 mm2 (range: 0.6-3.9). The SG diameter positively correlated with age. Our study demonstrates the ability of US to image the SG and estimate its normal diameter and CSA. Knowledge of how to identify and measure the SG during ultrasound-guided procedures would be expected to decrease the risk of associated complications and help establish normal reference values.

Investigation of Optimal Needle Position for Radiofrequency Ablation-Based Blockade of Interspace between the Popliteal Artery and the Posterior Capsule of the Knee: A Cadaveric Study

Background and Objectives: The interspace between the popliteal artery and the posterior capsule of the knee (iPACK) block has been widely used in perioperative settings to control posterior knee pain and can additionally be used for chronic knee pain. In this cadaveric study, we aimed to investigate the needle tip position and its proximity to the articular branch of the tibial nerve (ABTN) during an iPACK-targeted radiofrequency procedure. Materials and Methods: An ultrasound-guided iPACK block was performed on 20 knees of 10 cadavers. We injected 0.1 mL each of blue and green gelatinous dye near the tibial artery (point A) and posterior knee capsule (point B), respectively, and evaluated the spread of both around the ABTN. For a hypothetical conventional radiofrequency ablation (RFA) lesion (diameter, 2.95 mm) and cooled RFA lesion (diameter, 4.9 mm), we counted the number of specimens in which the ABTNs would be captured. Results: The percentage of specimens in which the ABTN would be captured by a cooled RFA lesion was 64.71% at point A and 43.75% at point B (p = 0.334). Meanwhile, the percentage of specimens in which the ABTN would be captured by a conventional RFA lesion was 58.82% from point A and 25% from point B (p = 0.065). Conclusions: When performing an RFA-based iPACK block, the needle tip may be positioned either lateral to the tibial artery or in the space between the posterior knee capsule and the tibial artery. However, more studies with larger samples are needed to verify these results before the clinical use of this procedure can be recommended.

Sono-anatomy of the middle cervical sympathetic ganglion verified with pathology

Objectives

Cervical discomfort and other symptoms may be attributable to the middle cervical sympathetic ganglion. The aim of this study was to explore the sonographic features of this ganglion in anatomical specimens and cadavers and evaluate the feasibility of its visualization using high-resolution ultrasonography.

Methods

We examined three cervical sympathetic-ganglion specimens and two fresh cadavers using high-resolution ultrasound to explore the sonographic features of this ganglion. Basic imaging characteristics examined included the shape, echo intensity, and location of the ganglion. Core-needle biopsy was performed to examine the suspected middle cervical sympathetic ganglion in the two fresh cadavers and verify the accuracy of the sonographic identification via pathological examination.

Results

The middle cervical sympathetic ganglion appeared on high-resolution ultrasonography as an oval-shaped hypoechoic structure, with at least one continuous hypoechoic line connected to each ending in the anatomical specimens and fresh cadavers, and it was distinctly different from the adjacent lymph nodes.

Discussion

Based on an adequate understanding of both its location and sonographic features, the direct visualization of the middle cervical sympathetic ganglion using high-resolution ultrasonography is feasible.

Safety and Effectiveness of Stellate Ganglion Cryoablation in Complex Regional Pain Syndrome

This was a retrospective, observational, descriptive study to evaluate the safety and 6-month effectiveness of percutaneous cryoablation of the stellate ganglion for the treatment of complex regional pain syndrome (CRPS). Eight patients with CRPS diagnosed by Budapest criteria were treated with this procedure. CRPS symptom severity was assessed prior to the procedure and at 3-month intervals after the procedure using a novel CRPS scoring system-the Budapest score-created by the authors. The mean Budapest score prior to and 6 months (187 days, SD ± 43) after stellate ganglion cryoablation was 7.0 (SD ± 2.0) (n = 6) and 3.8 (SD ± 2.3) (n = 6), respectively, showing a decrease of 3.2 (SD ± 1.7) (n = 6; P = .006). There were no major adverse events due to the procedure, and there was only 1 minor adverse event. Stellate ganglion cryoablation is a feasible, safe, and minimally invasive procedure that may represent an efficacious adjunct treatment option for select patients with CRPS.

Pulsed radiofrequency to stellate ganglion for brachial plexus injury-induced complex regional pain syndrome: A case series

Brachial plexus injury (BPI) occurs commonly in young adults following trauma. This may result in the development of complex regional pain syndrome (CRPS) following injury, which is difficult to treat. We present a group of patients with CRPS secondary to BPI. These patients were managed with neuromodulation of the stellate ganglion (SG) with pulsed radiofrequency (PRF) and followed up for a period of 3 months to assess for pain relief and a decrease in the intake of medications after the intervention. PRF to SG was found to have significant pain relief lasting around three months.

Visualizing stellate ganglion with US imaging for guided SGB treatment: A feasibility study with healthy adults

Objective

As for ultrasound (US) guided stellate ganglion (SG) block, unsatisfactory curative outcomes and complications still remain. This problem could be greatly improved by identifying and monitoring SG. To the best of our knowledge, there are few reports to directly visualize SG in literature. This study explored the feasibility of detection of SG and summarized the findings of SG through US.

Methods

Fifty healthy adults with 100 SGs were enrolled. The size, shape, echogenicity, margin, the inferior pole of SG, the relationship between the superior pole of SG and the transverse process, the relationship between the superior pole of SG and the inferior thyroid artery, and the relationships between SG and other surrounding tissues were evaluated by US.

Results

The SG was identified in 79% of the participants. No significant differences were found between the right and left sides regarding thickness, cross-sectional area (CSA), and position (all p > 0.05); however, there was a significant difference in the width of the right and left sides (p < 0.05). Side was associated with SG visibility (p < 0.05), however, the gender was not (p > 0.05). A total of 42% of SGs were oval-shaped. All SGs were hyperechogenic and had an ill-defined margin. In fact, 63% of SGs were located in the C7 transverse process level, 77% of SGs were located under the inferior thyroid artery, and all of these SGs were located lateral to the thyroid and medial to the anterior scalene muscle and the vagus nerve.

Conclusion

Our preliminary study demonstrates that US imaging provides the capability of detecting SG. This may be helpful in minimizing complications and improving the accuracy of US-guided SG block.

Stellate ganglion intervention for chronic pain: A review

Stellate ganglion (SG) intervention is currently widely being studied in many kinds of chronic pain. As one of the convenient ways to treat the sympathetic nervous system, the indications for stellate ganglion intervention (SGI) include complex regional pain syndrome, postherpetic neuralgia, cancer pain of different origins, orofacial pain, and so forth. SGI refers to the reversible or irreversible blocking of the cervical sympathetic trunk, cervical sympathetic ganglion, and their innervation range through noninvasive or minimally invasive treatment. Current treatment options include stellate ganglion block (SGB), SG pulsed radiofrequency, continuous radiofrequency treatment, and noninvasive SGB. In particular, SGB continues to be one of the most studied methods in chronic pain management. However, a single SGB usually provides only short-term effects; repeated SGB may result in complications such as hoarseness, light-headedness, and vessel or nerve injury. Meanwhile, the mechanism of SGI is still unclear. This review discusses the research progress of SGI methods, effectiveness, complications, and possible mechanisms in the management of chronic pain.

Effect of the relative position of electrode and stellate ganglion during thermal radiofrequency ablation: a simulation study

PURPOSE

Stellate ganglion (SG) block by thermal radiofrequency ablation (RFA) is frequently conducted as a therapeutic intervention for sympathetic-maintained and neuropathic pain syndromes. RFA's partial lack of effectiveness could be partly due to the ablation zone (AZ) not completely covering the SG section and therefore preventing the 'cutting' of the afferent pathways. Our objective was to build a theoretical model to conduct computer simulations to assess the effect of the electrode position relative to the SG.

METHODS

A three-dimensional model was built including the SG and adjacent tissues (vertebrae C7-T1-T2, trachea, carotid artery and vertebral artery). RFA (90-s, 80 °C) was simulated considering a 22 G-5 mm electrode. The AZ was computed using the 50 °C isotherm.

RESULTS

An electrode displacement of 2 mm in any direction from the optimal position (centered on the SG) meant that the AZ did not fully cover the SG section. Likewise, SG size considerably affected the RFA effectiveness since the AZ fully covered the section of small but not large SGs.

CONCLUSIONS

The findings suggest that the currently used SG RFA settings (i.e., 22 G-5 mm electrode, 90-s, 80 °C) may not be appropriate due to their inability to achieve an AZ that fully covers the SG cross section under certain circumstances, such as a large SG and non-optimal positioning of the RF electrode with respect to the SG center.

Chronic refractory angina pectoris treated by bilateral stereotactic radiosurgical stellate ganglion ablation: first-in-man case report

Background

Refractory angina pectoris (AP) significantly impairs quality of life in patients with chronic coronary syndrome. Several minimally invasive methods (coronary sinus reducer, cell therapy, laser or shockwave revascularization, and spinal cord stimulation) or non-invasive methods (external counterpulzation) have been studied. However, their routine clinical use has not been widely implemented. Surgical or endoscopic sympathectomy is feasible for permanently relieving angina, but is often contraindicated due to the extent of complications associated with it. Neuromodulation by anaesthetic blockade of the left-sided stellate ganglion (SG) has been shown to relieve angina for days or weeks. To provide a long-term anti-anginal effect, novel pharmacological (phenol-based) or radiofrequency ablation techniques have been individually used to permanently destroy sympathetic pathways.

Case summary

We describe a first-in-man use of stereotactic radiosurgical SG ablation using a linear accelerator (CyberKnife) in a heart failure patient after myocardial infarction with chronic refractory AP. Repeated anaesthetic SG blockade in this patient resulted in a significant, but only short-term, clinical improvement. The left, and subsequently the right, SG was ablated by targeted irradiation. During the 1-year follow-up, the patient remained without angina. We did not observe any clinically relevant early or late complications. Atrial fibrillation that developed 2 months after the second procedure was deemed to be associated with a natural progression of co-existing heart failure.

Discussion

We conclude that stereotactic radiosurgical SG ablation has the potential to become a minimally invasive and low-risk procedure to treat refractory angina patients. However, this procedure needs to be evaluated in larger patient populations.

Effect of Stellate Ganglion Block on Intraoperative Propofol and Fentanyl Consumption in Patients with Complex Regional Pain Syndrome Undergoing Surgical Repair of Brachial Plexus Injury: A Randomized, Double-blind, Placebo-controlled Trial

Introduction

Stellate ganglion block (SGB) is commonly performed to treat chronic painful conditions, such as complex regional pain syndrome (CRPS) and postherpetic neuralgia. However, whether it is effective in reducing anesthesia and analgesia requirement during surgery (acute pain) is not known.

Materials and Methods

Sixty American Society of Anesthesiologists (ASA) physical status I and II patients with CRPS type II undergoing surgery for repair of brachial plexus injury were randomized (1:1) to receive SGB with either 10 mL of 0.5% bupivacaine (Group B) or a matching placebo (Group S) before induction of anesthesia.

Results

There was a significant reduction in the requirement of total intraoperative propofol (1659.7 ± 787.5 vs. 2500.7 ± 740.9 mg, P = 0.0003) and fentanyl (190.0 ± 82.5 vs. 327.3 ± 139.3, P = 0.0001) in Group B compared with Group S. Similarly, in Group B, the time to first analgesic was much longer (328 ± 219 vs. 64 ± 116 min, P = 0.000) and postoperative fentanyl requirement for 24 h was lesser compared to Group S (0.6 ± 1.1 vs. 2.1 ± 1.3 μg/kg, P = 0.000).

Conclusion

SGB is effective in reducing the requirement of intraoperative propofol and fentanyl as well as decreasing opioid requirement in the postoperative period in patients with CRPS type II undergoing surgery.

Interventional Radiofrequency Treatment for the Sympathetic Nervous System: A Review Article

Introduction

Interventional techniques such as radiofrequency (RF) treatment can be used to interrupt pain signals transmitted through the sympathetic nervous system (SNS). RF treatments including the pulsed (PRF) and continuous (CRF) modalities show enhanced control over lesion size and enhanced ability to confirm accurate positioning compared to other interventional methods. PRF also acts to reduce the area of the lesion. In this article, we characterize the currently available evidence supporting the use and efficacy of RF treatments in sympathetically mediated pain (SMP) conditions.

Study Design

A comprehensive literature review.

Methods

A PubMed and Cochrane Library database search was performed for human studies applying RF treatment at sympathetic sites (sphenopalatine ganglion, stellate ganglion, cervical, thoracic, or lumbar sympathetic ganglia, celiac plexus, splanchnic nerves, superior hypogastric plexus, and ganglion impar) between January 1970 to May 2020. Data were extracted, summarized into tables, and qualitatively analyzed.

Results

PRF and CRF both show promise in relieving SMP conditions, such as complex regional pain syndrome (CRPS), pain in the perineal region, headache and facial pain, and oncologic and non-oncologic abdominal pain, in addition to other types of pain, with minimal complications. Furthermore, in most comparative studies, outcomes using RF treatments exceeded other interventional techniques, such as anesthetic block and chemical neurolysis.

Conclusions

RF treatments can be effective in carefully selected patients who are refractory to conservative management. However, further randomized controlled studies are needed prior to implementing it into common practice.

Stellate Ganglion Blockade: an Intervention for the Management of Ventricular Arrhythmias

PURPOSE OF REVIEW

To highlight the indications, procedural considerations, and data supporting the use of stellate ganglion blockade (SGB) for management of refractory ventricular arrhythmias.

RECENT FINDINGS

In patients with refractory ventricular arrhythmias, unilateral or bilateral SGB can reduce arrhythmia burden and defibrillation events for 24-72 h, allowing time for use of other therapies like catheter ablation, surgical sympathectomy, or heart transplantation. The efficacy of SGB appears to be consistent despite the type (monomorphic vs polymorphic) or etiology (ischemic vs non-ischemic cardiomyopathy) of the ventricular arrhythmia. Ultrasound-guided SGB is safe with low risk for complications, even when performed on anticoagulation. SGB is effective and safe and could be considered for patients with refractory ventricular arrhythmias.

Pulsed radiofrequency of superior cervical ganglion for treatment of painful post-traumatic trigeminal neuropathy (PTTN): A case series report

Objective: Painful post-traumatic trigeminal neuropathy (PTTN) is a clinical pain syndrome that occurs due to injuries to the peripheral branches of the trigeminal nerve and is characterized by a deep burning pain and accompanied by positive and negative neurological signs. In patients with recalcitrant PTTN, the sympathetic nervous system is a potential therapeutic target. The aim of this study was to investigate the therapeutic response of PTTN patients to pulsed radiofrequency treatment (PRF) of the superior cervical sympathetic ganglion (SCG).Methods: Thirty-five patients with PTTN who had a history of severe disabling facial neuropathic pain underwent PRF of the SCG under a new lateral fluoroscopic approach.Results: The patients' pain intensity post-PRF was 3.94 (± 3.11), compared with 8.82 (± 1.27) pre-PRF (p < .001).Conclusion: PRF of the SCG could be an effective method to treat chronic PTTN.

CT-Guided Stellate Ganglion Pulsed Radiofrequency Stimulation for Facial and Upper Limb Postherpetic Neuralgia

Objective: Postherpetic neuralgia (PHN) is the most common complication of herpes zoster, manifesting as a persistent, spontaneous, knife-like pain or paroxysmal burning that seriously affects a patient’s quality of life. An effective treatment of PHN is lacking. This retrospective study examined the efficacy and safety of stellate ganglion (SG) pulsed radiofrequency (PRF) on facial and upper limb PHN.

Methods: Eighty-four patients with PHN on the face or upper limbs were enrolled for the study. Patients were randomly divided into two surgical groups according to the order of enrollment; one group underwent SG block (SG-B group, n = 42) and the other underwent SG pulsed radiofrequency (SG-P group, n = 42). After surgery, patients were followed at 1 week, 2 weeks, 1 month, 3 months, and 6 months. Observation at each follow-up included basic patient characteristics, visual analog scale (VAS), quality of life (QOL) using Physical Component Summary (PCS), and Mental Component Summary (MCS) to assess, total effective rate, complications and side effects.

Results: Compared with preoperative values, VAS decreased in both groups after surgery (P < 0.05). In the SG-B group, VAS increased after 1 month, while in the SG-P group, VAS gradually decreased at later follow-up time points. VAS decreased more significantly in the SG-P group after 1 month (P < 0.05). PCS and MCS increased in both groups after the operation, and the difference was significant compared with preoperative values (P < 0.05). The total effective rates of the SG-B and SG-P groups were 64.3 and 83.3%, respectively. The total effective rate of the SG-P group was higher than that of the SG-B group (P < 0.05). The incidence of complications and side effects in the SG-B group was higher than that in the SG-P group (P < 0.05).

Conclusion: SG pulsed radiofrequency treatment of facial and upper limb PHN is safe and effective. It is a treatment method worth promoting.

Detection of the Stellate and Thoracic Sympathetic Chain Ganglia with High-Resolution 3D-CISS MR Imaging

BACKGROUND AND PURPOSE

Despite the importance of the sympathetic nervous system in homeostasis and its putative role in various disease states, little is known regarding our ability to image the sympathetic chain and sympathetic chain ganglia, perhaps owing to their small size. In this retrospective study, we sought to evaluate the normal anatomy of the sympathetic chain ganglia and assess the detectability of the sympathetic chain and sympathetic chain ganglia on high-resolution 3D-CISS images.

MATERIALS AND METHODS

This study included 29 patients who underwent 3D-CISS MR imaging of the thoracic spine for reasons unrelated to abnormalities of the sympathetic nervous system. Patients with a prior spinal operation or visible spinal pathology were excluded. The sympathetic chain ganglia were evaluated using noncontrast 3D-CISS MR imaging. Statistical analyses included t tests and measures of central tendency. The Cohen κ statistic was calculated to evaluate interrater reliability.

RESULTS

The stellate ganglion and thoracic chain ganglia were identified in all subjects except at the T10-T11 and T11-T12 levels. The stellate ganglion was found inferomedial to the subclavian artery and anterior and inferior to the transverse process of C7 in all subjects. Thoracic sympathetic chain ganglia were identified ventral to the costovertebral junction in all subjects from T2 to T10. There was strong interobserver agreement for the detection of the sympathetic chain ganglia with κ > 0.80. The size, shape, and location of these structures corresponded with gross anatomic and surgical observations.

CONCLUSIONS

The thoracic sympathetic chain ganglia can be identified on precontrast 3D-CISS MR imaging. This technique may aid in the initial evaluation of stellate ganglion and/or sympathetic chain ganglia size and signal change for comparison in future studies.

Ultrasound-guided pulsed radiofrequency treatment of the cervical sympathetic chain for complex regional pain syndrome: A retrospective observational study

The stellate ganglion is a common target to manage neuropathic pain in the upper extremities. However, the effect duration of a single stellate ganglion block is often temporary. To overcome the short-term effects of a single sympathetic block, pulsed radiofrequency (PRF) can be applied. The aim of the present study was to investigate the efficacy of PRF on the cervical sympathetic chain under ultrasound guidance for complex regional pain syndrome (CRPS).Twelve CRPS patients who underwent PRF on the cervical sympathetic chain were enrolled in this retrospective analysis. Under ultrasound guidance, PRF was performed for 420 seconds at 42°C on the C6- and C7-level sympathetic chain.The pain intensity decreased significantly at 1 week after the procedure. Overall, 91.7% of patients experienced at least moderate improvement. A positive correlation was observed between the extent of pain reduction at 1 week after PRF and the degree of overall benefit (r = 0.605, P = 0.037). This reduction in symptoms was maintained for a mean of 31.41 ± 26.07 days after PRF. There were no complications associated with this procedure.PRF on the cervical sympathetic chain, which can be performed easily and safely under ultrasound guidance, should be considered an option for managing CRPS of the upper extremities.

Local anaesthetic sympathetic blockade for complex regional pain syndrome

BACKGROUND

This review is an update of a previously published review in the Cochrane Database of Systematic Reviews, 2005, Issue 4 (and last updated in the Cochrane Database of Systematic Reviews, 2013 issue 8), on local anaesthetic blockade (LASB) of the sympathetic chain to treat people with complex regional pain syndrome (CRPS).

OBJECTIVES

To assess the efficacy of LASB for the treatment of pain in CRPS and to evaluate the incidence of adverse effects of the procedure.

SEARCH METHODS

For this update we searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2015, Issue 9), MEDLINE (Ovid), EMBASE (Ovid), LILACS (Birme), conference abstracts of the World Congresses of the International Association for the Study of Pain, and various clinical trial registers up to September 2015. We also searched bibliographies from retrieved articles for additional studies.

SELECTION CRITERIA

We considered randomised controlled trials (RCTs) that evaluated the effect of sympathetic blockade with local anaesthetics in children or adults with CRPS compared to placebo, no treatment, or alternative treatments.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. The outcomes of interest were reduction in pain intensity, the proportion who achieved moderate or substantial pain relief, the duration of pain relief, and the presence of adverse effects in each treatment arm. We assessed the evidence using GRADE (Grading of Recommendations Assessment, Development and Evaluation) and created a 'Summary of findings' table.

MAIN RESULTS

We included an additional four studies (N = 154) in this update. For this update, we excluded studies that did not follow up patients for more than 48 hours. As a result, we excluded four studies from the previous review in this update. Overall we included 12 studies (N = 461), all of which we judged to be at high or unclear risk of bias. Overall, the quality of evidence was low to very low, downgraded due to limitations, inconsistency, imprecision, indirectness, or a combination of these.Two small studies compared LASB to placebo/sham (N = 32). They did not demonstrate significant short-term benefit for LASB for pain intensity (moderate quality evidence).One small study (N = 36) at high risk of bias compared thoracic sympathetic block with corticosteroid and local anaesthetic versus injection of the same agents into the subcutaneous space, reporting statistically significant and clinically important differences in pain intensity at one-year follow-up but not at short term follow-up (very low quality evidence).Of two studies that investigated LASB as an addition to rehabilitation treatment, the only study that reported pain outcomes demonstrated no additional benefit from LASB (very low quality evidence).Eight small randomised studies compared sympathetic blockade to various other active interventions. Most studies found no difference in pain outcomes between sympathetic block versus other active treatments (low to very low quality evidence).One small study compared ultrasound-guided LASB with non-guided LASB and found no clinically important difference in pain outcomes (very low quality evidence).Six studies reported adverse events, all with minor effects reported.

AUTHORS' CONCLUSIONS

This update's results are similar to the previous versions of this systematic review, and the main conclusions are unchanged. There remains a scarcity of published evidence and a lack of high quality evidence to support or refute the use of local anaesthetic sympathetic blockade for CRPS. From the existing evidence, it is not possible to draw firm conclusions regarding the efficacy or safety of this intervention, but the limited data available do not suggest that LASB is effective for reducing pain in CRPS.

The Utility of Peripheral Nerve Blocks in Interventional Radiology

OBJECTIVE

The aim of this article is to provide an overview of peripheral nerve blocks, the use of peripheral nerve block within and outside interventional radiology, and the complications of peripheral nerve block.

CONCLUSION

Interventional radiologists are often responsible for sedation and pain management in the majority of interventional radiology procedures. Peripheral nerve block is increasingly being used in interventional radiology.

Pulsed radiofrequency applied to the dorsal root ganglia for treatment of post-stroke complex regional pain syndrome: A case series

STUDY OBJECTIVE

Complex regional pain syndrome is a painful and disabling syndrome where the patient presents with neuropathic pain, edema, or vasomotor or pseudomotor abnormalities that are often refractory to treatment. Complex regional pain syndrome type 1 may occurs in stroke patients. Radiofrequency is a therapeutic modality that has been used for years for diseases associated with neuropathic pain.

DESIGN

Case series report.

SETTING

Selcuk University Hospital.

PATIENTS

A 69-year-old woman and a 48-year-old women who suffered post-stroke complex regional pain syndrome type 1.

INTERVENTIONS

Pulsed radiofrequency current application to the cervical dorsal root ganglia.

MEASUREMENTS

Pain reduction.

MAIN RESULTS

The patients had complete resolution of their symptoms, which was maintained at 10 and 5 months of follow-up.

CONCLUSIONS

These cases illustrates that pulsed radiofrequency applied to cervical dorsal root ganglia might play a significant role in multi-modal approach of complex regional pain syndrome type 1 management after stroke. Further randomized, controlled studies are needed to support this argument.

Stellate ganglion pulsed radiofrequency ablation for stretch induced complex regional pain syndrome type II

Complex regional pain syndrome (CRPS) following injury or nerve damage, as its name signifies, is a challenging entity, and its successful management requires a multidisciplinary approach. It not only manifests as severe pain, but also gives rise to functional disability, lack of sleep, lack of enjoyment of life and poor quality of life. Various pain interventional techniques have been described in the literature for the management of CRPS ranging from sympathetic blocks to spinal cord stimulator. A 34-year-old liver transplant donor, who developed position-induced right upper limb neuropathic pain suggestive of CRPS type II was managed initially with medications and later with stellate ganglion block under fluoroscopic guidance at cervical C7 position. Following an initial significant improvement in pain and allodynia, which was transient, a pulsed radiofrequency ablation of stellate ganglion was performed successfully to provide prolonged and sustained pain relief, which persisted up to 14 months of follow-up.

[Interventional pain therapy. Results of a survey among specialized pain physicians in Germany]

BACKGROUND

Interventional pain therapy aims to treat pain which is refractory to pharmacologic and noninterventional treatment. Due to the partly lacking evidence and recommendations it remains unclear when interventional methods should be applied within the treatment pathway. This study assesses the current state of interventional methods in Germany and their leading indications comparing with the recommendations found in the literature.

METHODS

An online survey was conducted among German physicians specialized in pain therapy concerning the number of interventions they perform per quarter, which supporting measures they use, and their indications for sympathetic blocks, sensory blocks, intrathecal administration, and spinal cord stimulation.

RESULTS

A total of 109 physicians (23.5 %) participated in the survey. Blocks are most often performed on the stellate ganglion (94 %) and on the superior cervical ganglion (82 %). They are supported by anatomical landmarks and less often by imaging control. Both classic neuropathic pain diagnoses (e.g., complex regional pain syndrome) and diagnoses with a neuropathic pain component (e.g., peripheral arterial disease, tumor pain, and back pain) were considered as indications to perform interventional procedures.

CONCLUSION

Although there is no clear evidence on interventional procedures in the current literature, these methods are often performed by the respondents. Anatomic landmarks are most frequently used for orientation. The German pain physicians who responded consider especially neuropathic pain as an indication to perform interventional procedures for pain therapy.

Analgesic efficacy of pre-operative stellate ganglion block on postoperative pain relief: a randomised controlled trial

We undertook a randomised, double-blind, placebo-controlled study to compare the analgesic efficacy of pre-operative stellate ganglion block on postoperative pain relief after upper limb orthopaedic surgery. Patients were administered a 3-ml injection during ultrasound-guided stellate ganglion block; 15 patients received lidocaine 2% and 15 patients received 0.9% saline. Following the block, all patients received standardised general anaesthesia. Postoperative analgesia included regular intravenous diclofenac, paracetamol and patient-controlled analgesia with tramadol for 24 h. Patients were observed at 0, 2, 4, 6, 8, 12 and 24 h after surgery for tramadol consumption, cardiovascular variables and visual analogue scale pain scores at rest and on movement. The mean (SD) hourly tramadol consumption was significantly reduced in the lidocaine group compared with the saline group at 4 h (8.0 (10.1) mg vs 28.0 (12.6) mg, respectively; p = 0.001), 6 h (5.3 (10.8) mg vs 17.3 (12.7) mg, respectively; p = 0.013) and 8 h (5.3 (11.8) mg vs 21.3 (9.1) mg, respectively; p = 0.001). The cumulative 24-h tramadol consumption was 97.3 (16.6) mg in the lidocaine group and 150.6 (26.0) mg in the saline group (p = 0.001). There were significant differences in the pain visual analogue scale at rest at two time points; at 4 h the median (IQR [range]) visual analogue scale scores were 4 (4-6 [2-8]) in the lidocaine group and 5 (4-6 [2-7]) in the saline group (p = 0.03), and at 6 h visual analogue scale scores were 3 (3-4 [3-6]) and 4 (4-6 [2-7]), respectively (p = 0.04). Pain visual analogue scale on movement was lower in the lidocaine group at all time intervals compared with the saline group, but this did not reach statistical significance. The present study has demonstrated a postoperative tramadol-sparing and analgesic effect of pre-operative stellate ganglion block in patients undergoing upper limb orthopaedic surgery under general anaesthesia.