Efficacy of ganglion impar block combined with pudendal nerve pulsed radiofrequency for pudendal neuralgia management-a randomized clinical trial.

BACKGROUND: Pudendal neuralgia is a chronic and debilitating condition. Its prevalence ranges from 5 to 26%. Currently, therapeutic approaches to treat pudendal neuralgia include patient education, medication management, psychological and physical therapy, and procedural interventions, such as nerve block, trigger point injections, and surgery. Drug therapy has a limited effect on pain relief. A pudendal nerve block may cause a significant decrease in pain scores for a short time; however, its efficacy significantly decreases over time. In contrast, pudendal nerve pulsed radiofrequency can provide pain relief for 3 months, and ganglion impar block has been widely used for treating chronic perineal pain and chronic coccygodynia. This study aimed to determine the efficacy and safety of monotherapy (pudendal nerve pulsed radiofrequency) and combination therapy (pudendal nerve pulsed radiofrequency plus ganglion impar block) in patients with pudendal neuralgia. METHODS: This randomized, controlled clinical trial will include 84 patients with pudendal neuralgia who failed to respond to drug or physical therapy. Patients will be randomly assigned into one of the two groups: mono or combined treatment groups. The primary outcome will be a change in pain intensity measured using the visual analog scale. The secondary outcomes will include a Self-Rating Anxiety Scale score, Self-Rating Depression Scale score, the use of oral analgesics, the Medical Outcomes Study Health Survey Short Form-36 Item score, and the occurrence of adverse effects. The study results will be analyzed using intention-to-treat and per-protocol analyses. Primary and secondary outcomes will be evaluated between the mono and combined treatment groups. Subgroup analyses will be conducted based on the initial ailment, age, and baseline pain intensity. The safety of the treatment will be assessed by monitoring adverse events, which will be compared between the two groups. DISCUSSION: This study protocol describes a randomized, controlled clinical trial to determine the efficacy and safety of mono and combination therapies in patients with pudendal neuralgia. The study results will provide valuable information on the potential benefits of this combination therapy and contribute to the development of more effective and safer treatments for patients with pudendal neuralgia. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR2200061800).

Efficacy of ultrasound-guided stellate ganglion block in relieving acute postoperative pain: a systematic review and meta-analysis.

OBJECTIVE: The efficacy of ultrasound-guided stellate ganglion block (SGB) in alleviating postoperative pain remains unclear. This meta-analysis was performed to determine the efficacy of ultrasound-guided SGB in relieving acute postoperative pain in patients undergoing surgery with general anesthesia. METHODS: This systematic review and meta-analysis focused on randomized controlled trials comparing SGB with control or placebo. The primary outcome was the pain score at 24 hours after surgery. A random-effects model was used to calculate the mean difference (MD) or risk ratio with a confidence interval (CI) of 95%. RESULTS: Eight studies involving 470 patients were included in the meta-analysis. The results revealed that ultrasound-guided SGB was significantly associated with a lower pain score at 24 hours after surgery (MD = -0.74; 95% CI = -1.39, -0.08; I2 = 86%; low evidence) and at 8 hours after surgery (MD = -0.65; 95% CI = -1.03, -0.28; I2 = 29%; moderate evidence). CONCLUSION: Ultrasound-guided SGB is effective in alleviating acute postoperative pain. However, considering the limited number of trials performed to date, more large-scale and high-quality randomized controlled trials are required to confirm these findings.

A Multicenter Study of Stellate Ganglion Block as a Temporizing Treatment for Refractory Ventricular Arrhythmias.

BACKGROUND: Ventricular tachycardia (VT) and ventricular fibrillation (VF) are life-threatening conditions and can be refractory to conventional drug and device interventions. Stellate ganglion blockade (SGB) has been described as an adjunct, temporizing intervention in patients with refractory ventricular arrhythmia. We examined the association of SGB with VT/VF in a multicenter registry. OBJECTIVES: This study examined the efficacy of SGB for treatment/temporization of refractory VT/VF. METHODS: The authors present the first analysis from a multicenter registry of patients treated for refractory ventricular arrhythmia at a clinical site in the Czech Republic and the United States. Data were collected between 2016 and 2022. SGB was performed at the bedside by anesthesiologists and/or cardiologists. Outcomes of interest were VT/VF burden and defibrillations at 24 hours before and after SGB. RESULTS: In total, there were 117 patients with refractory ventricular arrhythmias treated with SGB at Duke (n = 49) and the Institute for Clinical and Experimental Medicine (n = 68). The majority of patients were male (94.0%), were White (87.2%), and had an implantable cardioverter-defibrillator (70.1%). The most common etiology of heart disease was ischemic cardiomyopathy (52.1%), and monomorphic VT was the most common morphology (70.1%). Within 24 hours before SGB (0-24 hours), the median episodes of VT/VF were 7.5 (Q1-Q3: 3.0-27.0), and 24 hours after SGB, the median decreased to 1.0 (Q1-Q3: 0.0-4.5; P < 0.001). At 24 hours before SGB, the median defibrillation events were 2.0 (Q1-Q3: 0.0-8.0), and 24 hours after SGB, the median decreased to 0.0 (Q1-Q3: 0.0-1.0; P < 0.001). CONCLUSIONS: In the largest cohort of patients with treatment-refractory ventricular arrhythmia, we demonstrate that SGB use was associated with a reduction in the ventricular arrhythmia burden and need for defibrillation therapy.

Safety and Efficacy of Ultrasound-Guided Sympathetic Blockade by Proximal Intercostal Block in Electrical Storm Patients.

BACKGROUND: Electrical storm (ES) patients who fail standard therapies have a high mortality rate. Previous studies report effective management of ES with bedside, ultrasound-guided percutaneous stellate ganglion block (SGB). We report our experience with sympathetic blockade administered via a novel alternative approach: proximal intercostal block (PICB). Compared with SGB, this technique targets an area typically free of other catheters and support devices, and may pose less strict requirements for anticoagulation interruption, along with lower risk of focal neurological side effects. OBJECTIVES: The authors sought to describe the safety and efficacy of PICB in patients with refractory ES. METHODS: We reviewed our institutional data on ES patients who underwent PICB between January 2018 and February 2023 to analyze procedural safety and short- and long-term outcomes. RESULTS: A total of 15 consecutive patients with ES underwent PICB during this period. Of those, 11 patients (73.3%) were maintained on PICB alone, and 4 patients (26.6%) were maintained on combined block with SGB and PICB. Overall, 72.7% patients who were maintained on PICB alone and 77.8% patients who were maintained on bilateral PICB had excellent arrhythmia suppression. After PICB, implantable cardioverter-defibrillator therapies were significantly reduced (P < 0.05), with 93.3% of patients receiving PICB having no implantable cardioverter-defibrillator shock until discharge or heart transplant. Anticoagulation was continued in all patients and there were no procedure-related complications. Apart from mild transient neurological symptoms seen in 3 patients, no significant neurological or hemodynamic sequelae were observed. CONCLUSIONS: In patients with refractory ES, continuous PICB provided safe and effective sympathetic block (77.8% ventricular arrhythmia suppression), achievable without interruption of anticoagulation, and without significant side effects.

Efficacy and safety of stellate ganglion block with different volumes of ropivacaine to improve sleep quality in patients with insomnia: a comparative study.

OBJECTIVE: The aim of this study was to compare the efficacy and safety of ultrasound-guided stellate ganglion block (SGB) with different volumes of 0.375% ropivacaine on sleep quality in patients with insomnia. PATIENTS AND METHODS: A total of 80 patients who were selected to undergo SGB for the treatment of insomnia were enrolled. The patients were divided into saline control group, and low-volume (4 mL), medium-volume (6 mL), and high-volume (8 mL) ropivacaine injection groups according to the random table method. The treatment included 7 blocks with once every three days. The left and right stellate ganglions are alternately blocked. The onset and maintenance time of Horner syndrome, the degree of carotid artery dilation and blood flow velocity before and 20 minutes after the first block, the occurrence of complications such as drug crossing of the midline of the artery and hoarse throat were recorded, and the improvement of sleep disorders was evaluated with the Pittsburgh Sleep Quality Index Scale. RESULTS: Horner syndrome occurred in 100% of all volumes of ropivacaine block. The ipsilateral internal carotid artery was dilated and was accompanied by increased blood flow. The degree of dilation and increase in blood flow were not affected by the volumes of drug injection. There were no serious complications in any group, but the incidences of hoarseness and dysphagia were higher in the medium- and high-volume groups than those in the low-volume group (all p < 0.05). Compared with the low- and medium-volume groups, the high-volume group had a faster onset of action, longer maintenance time, and the highest chance of the drug crossing the artery (all p < 0.05). Compared to those before the pre-block and in the control groups, insomnia was improved in all volume groups after the block with nonsignificant intergroup differences. CONCLUSIONS: 4 mL of 0.375% ropivacaine for ultrasound-guided SGB is sufficient to improve the sleep quality of insomnia patients, whose overall risk is lower than block with 6 mL or 8 mL of ropivacaine.

[Ultrasound-guided low-volume continuous cervical sympathetic nerve block for treatment of an electrical storm]. / Ultraschallgestützte kontinuierliche zervikale Sympathikusblockade mit Niedrigvolumina zur Therapie bei anhaltender ventrikulärer Tachykardie.

In addition to the treatment for complex regional pain syndrome (CRPS), the stellate ganglion block is a treatment option for refractory intermittent ventricular tachycardia (VT). Despite the use of imaging techniques, such as fluoroscopy and ultrasound, numerous side effects and complications have been reported. These are a result of the complex anatomical site and the volume of injected local anesthetics. This article reports on the catheter placement for continuous block of the cervical sympathetic trunk with high-resolution ultrasound imaging (HRUI) in a patient with intermittent VT. The tip of the cannula was placed on the anterior aspect of the longus colli muscle and 20 mg prilocaine 1% (2 ml) was injected. The VT stopped and a continuous infusion of 1 ml/h ropivacaine 0,2 % was started. Nevertheless, during the next hour the patient developed hoarseness and dysphagia, so that a block of the recurrent laryngeal nerve and the deep ansa cervicalis (C1-C3) was carried out. The infusion was paused and restarted later with 0.5 ml/h. The spread of the local anesthetic was controlled by ultrasound. Over the next 4 days the patient showed no VT or detectable side effects. After implantation of a defibrillator 1 day later the patient could then be discharged home on the following day. This case shows that the HRUI can be advantageously used in the catheter placement and also when adjusting the flow rate. In this way the risk of complications and side effects related to the puncture and local anesthetic volume can be reduced.

Intra-Cardiac Arrest Use of Stellate Ganglion Block for Refractory Ventricular Tachycardia.

BACKGROUND: Refractory ventricular dysrhythmia, or electrical storm, is a cardiac condition consisting of three or more episodes of ventricular dysrhythmia resistant to treatment within a 24-hour period. These dysrhythmias carry high morbidity and mortality if not diagnosed and abated promptly. When traditional resuscitative algorithms fail to return a patient to a perfusing rhythm, providers need to consider other, more novel techniques to terminate these dangerous dysrhythmias. One approach is the use of a stellate ganglion block, which has been documented in the literature only a handful of times for its resuscitative use in cardiac arrest. CASE SERIES: This case series details two cases from an urban emergency department (ED) in a large metropolitan city, where the use of ultrasound-guided stellate ganglion blocks during cardiac arrest provided successful ablation of the tachydysrhythmia. The first case involves a patient who went into cardiac arrest while in the ED and was found to be in refractory pulseless ventricular tachycardiawhile. The second case describes a patient who went into a witnessed out-of-hospital cardiac arrest while with emergency medical services. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: The stellate ganglion block is a procedure currently being used as a treatment modality for a variety of neurologic, psychological, and cardiac conditions. This intervention may provide a viable and lifesaving option for emergency physicians to adopt when traditional resuscitative algorithms fail to break resistant ventricular tachydysrhythmias.

Clinical results of lumbar sympathetic blocks in lower limb complex regional pain syndrome using infrared thermography as a support tool.

AIM: To describe the clinical outcomes for a group of complex regional pain syndrome patients using infrared thermography as an intraprocedural support tool when undertaking fluoroscopy-guided lumbar sympathetic blocks. SUBJECTS: 27 patients with lower limb complex regional pain syndrome accompanied by severe pain and persistent functional impairment. METHODS: A series of three fluoroscopic-guided lumbar sympathetic blocks with local anesthetic and corticoids using infrared thermography as an intraprocedural support tool were performed. Clinical variables were collected at baseline, prior to each block, and one, three, and six months after blocks in a standardized checklist assessing each of the clinical categories of complex regional pain syndrome stipulated in the Budapest criteria. RESULTS: 23.75% of the blocks required more than one chance to achieve the desired thermal pattern and therefore to be considered as successful. A decrease in pain measured on a visual analogic scale was observed at all time points compared to pre-blockade data, but only 37% of the cases were categorized as responders, representing a ≥ 30% decrease in VAS, with the disappearance of pain at rest. An improvement of most of the clinical variables recorded was observed, such as tingling, edema, perception of thermal asymmetry, difference in coloring and sweating. There was a significant decrease of neuropathic pain and improvement of functional limitation. Logistic regression analysis showed the main variable to explain the probability of being a responder was immobilization time (odds ratio of 0.89). CONCLUSION: A series of fluoroscopy-guided lumbar sympathetic blocks controlled by infrared thermography in the treatment of lower limb CRPS showed a responder rate of 37%.

Stellate ganglion instrumentation for pharmacological blockade, nerve recording, and stimulation in patients with ventricular arrhythmias: Preliminary experience.

BACKGROUND: Stellate ganglion blockade (SGB) can control ventricular arrhythmias (VAs), but outcomes are unclear. Percutaneous stellate ganglion (SG) recording and stimulation in humans has not been reported. OBJECTIVE: The purpose of this study was to assess the outcomes of SGB and the feasibility of SG stimulation and recording in humans with VAs. METHODS: Two patient cohorts were included-group 1: patients undergoing SGB for drug-refractory VAs. SGB was performed by injection of liposomal bupivacaine. Incidence of VAs at 24 and 72 hours and clinical outcomes were collected; group 2: patients undergoing SG stimulation and recording during VA ablation; a 2-F octapolar catheter was placed at the SG at the C7 level. Recording (30 kHz sampling, 0.5-2 kHz filter) and stimulation (up to 80 mA output, 50 Hz, 2 ms pulse width for 20-30 seconds) was performed. RESULTS: Group 1 included 25 patients [age 59.2 ± 12.8 years; 19 (76%) men] who underwent SGB for VAs. Nineteen patients (76.0%) were free of VA up to 72 hours postprocedure. However, 15 (60.0%) had VAs recurrence for a mean of 5.47 ± 4.52 days. Group 2 included 11 patients (mean age 63 ± 12.7 years; 82.7% men). SG stimulation caused consistent increases in systolic blood pressure. We recorded unequivocal signals with temporal association with arrhythmias in 4 of 11 patients. CONCLUSION: SGB provides short-term VA control, but has no benefit in the absence of definitive VA therapies. SG recording and stimulation is feasible and may have value to elicit VA and understand neural mechanisms of VA in the electrophysiology laboratory.

Stellate ganglion block catheters for refractory electrical storm: a retrospective cohort and care pathway.

BACKGROUND: Electrical storm can be challenging to treat, requiring a multidisciplinary team to coordinate medical management and invasive procedures. As the stellate ganglion provides efferent sympathetic outflow to the myocardium, stellate ganglion blocks (SGB) can be used to combat ventricular arrhythmias that arise from sympathetic overactivity. Data are scarce regarding SGB catheters as a treatment for electrical storm. We reviewed our use of SGB catheters for refractory electrical storm using our pathway collaboratively developed by critical care, cardiology, and regional anesthesia teams. METHODS: We conducted a retrospective cohort study of patients who underwent an SGB for electrical storm between January 2020 and April 2022 in our cardiovascular intensive care unit. The primary outcome was the sustained cessation of electrical storm for 24 hours. RESULTS: Upon chart review, 27 patients were identified and 11 met inclusion criteria. Cessation of electrical storm for 24 hours was achieved in 90% (n=10) of patients after left SGB. Similarly, 90% (n=10) had no documented episodes of ventricular arrhythmias requiring intervention within 6 hours after SGB. CONCLUSIONS: SGBs can interrupt or treat electrical storm. SGB catheters allow for prolonged arrhythmia cessation without repeated blocks and decrease the risk of repeat episodes of ventricular arrhythmias.

Stellate ganglion block for non-pain indications: a scoping review.

INTRODUCTION: Stellate ganglion block (SGB) is performed to relieve head, face, neck, or upper limb pain, and several non-pain indications for performing this block have emerged over the years. To date, there has been no attempt to synthesize evidence on SGB for treating non-pain indications. This scoping review presents a summary of the efficacy and adverse effects of SGB when performed for 6 non-pain indications. METHODS: This scoping review was accomplished through the use of Arksey and O'Malley framework. A literature search was conducted for relevant articles in medical databases to identify publications on SGB and specified study types. Two reviewers independently assessed the risk of bias for randomized controlled trials, nonrandomized comparative studies, and case series. Results were summarized and recommendations were made on the basis of the strength of the available evidence according to the US Preventative Services Task Force grading system. RESULTS: Twenty-four studies (19 randomized controlled trials and 5 nonrandomized studies) were included in this review. On the basis of the evidence, SGB is recommended for obtunding cardiovascular sympathetic stimulation, improving perfusion in limbs, and alleviating menopausal symptoms with a Grade B or C recommendation and a moderate-to-low level of certainty. There was insufficient evidence to recommend SGB for the other indications. CONCLUSIONS: SGB can be considered for obtunding cardiovascular sympathetic stimulation and stress response, reducing vascular tone to improve vascular insufficiency in the limbs and perioperative hemodynamic stability, and alleviating hot flashes in menopause, in conditions refractory to conventional medical management.

Use of thoracoscopy for thoracic sympathetic nerve block in primary hyperhidrosis.

Thoracic sympathetic nerve block (TSNB) has been widely used in the treatment of neuropathic pain. To reduce block failure rates, TSNB is assisted with several modalities including fluoroscopy, computed tomography, and ultrasonography. The present study describes our experience assessing the usefulness of thoracoscopy in TSNB for predicting compensatory hyperhidrosis before sympathectomy in primary hyperhidrosis. From September 2013 to October 2021, TSNB was performed under local anesthesia using a 2-mm thoracoscope in 302 patients with severe primary hyperhidrosis. Among the 302 patients, 294 were included for analysis. The target level of TSNB was T3 in almost all patients. The mean procedure time was 21 min. Following TSNB, the mean temperature of the left and right palms significantly changed from 31.5 to 35.3 °C and from 31.5 to 34.8 °C, respectively. With TSNB, primary hyperhidrosis was relieved in all patients. Pneumothorax occurred in six patients, in which no chest tube insertion was required. One patient developed hemothorax and was discharged the next day after small-bore catheter drainage. Transient ptosis developed in 10 patients and improved within a day in all patients. Our experiences showed that thoracoscopic TSNB is accurate, safe, and feasible to block the thoracic sympathetic nerve in patients with severe primary hyperhidrosis.

Human lumbar sympathetic blockade: An anatomical study to address potential block failure.

The lumbar sympathetic block is often used to treat complex regional pain syndrome, but it seems to have a high failure rate. This study seeks anatomical explanations for this apparent failure in order to refine our block procedure. Two simulated sympathetic trunk blocks were carried out on four fresh, cryopreserved unembalmed human cadavers under fluoroscopic control at the L2 vertebral body level, followed by two further simulated blocks at the L4 vertebral body level on the other side. Dye was injected, and the areas were dissected following a specific protocol. We then describe the anatomy and the spread of the dye compared to the spread of the contrast medium on fluoroscopy. The ganglia were differently located at different vertebral levels, and differed among the cadavers. Following this anatomical clarification, we now prefer to perform lumbar sympathetic blocks at the fourth lumbar vertebra level, using an extraforaminal approach at the caudal end of ​​the vertebra, avoiding the anterolateral margin of the vertebral body at the midpoint.

Efficacy and mechanism of stellate ganglion block in patients undergoing carotid endarterectomy.

OBJECTIVES: Carotid endarterectomy (CEA) is an effective technique for carotid artery stenosis and has been widely used. Stellate ganglion block (SGB) has good effect on the treatment of both painful and non-painful diseases. To investigate the efficacy of SGB in terms of cerebral protection in patients undergoing CEA and to analyze its mechanism. METHODS: In this retrospective analysis, 120 patients who underwent CEA were enrolled and divided into study group (SG) (60 cases, general anesthesia and SGB) and control group (CG) (60 cases, general anesthesia). The differences in hemodynamic indexes, middle cerebral artery (MCA) hemodynamic indexes, and endocrine-related indexes between the two groups at the baseline, after induction of anesthesia (induction), and skin incision (incision) were compared. The differences in neurological function and pain level between two groups 1 day pre-operatively (pre-op 1), 1 day postoperatively (POD 1), 2 day postoperatively (POD 2), and 7 day postoperatively (POD 7) were also evaluated. Perioperative adverse events and intraoperative anesthetics dosage were compared between two groups. RESULTS: The systolic blood pressure, diastolic blood pressure, mean pulse pressure difference, and heart rate of SG at incision were lower than those of the CG (p < 0.05); Vs, Vd, and Vm of MCA were significantly higher in the SG than in CG at induction and incision (p < 0.05). Cortisol and aldosterone levels were lower and potassium and insulin levels were higher in the SG than in CG at induction and incision (p < 0.05); At pre-op 1, POD 1, POD 2, and POD 7, the VAS scores of patients in the SG were significantly lower than those in CG at POD 1, POD 2, and POD 7 (p < 0.05). The patients in SG showed decreased incidence of perioperative adverse events compared with the CG (p < 0.05); The consumption of anesthetics in the SG was lower than that in CG (p < 0.05). CONCLUSION: SGB in patients undergoing CEA treatment can improve perioperative cerebral blood supply and reduce the consumption of anesthetics and the incidence of perioperative adverse events, which is safe and feasible as a cerebral protection measure. Meanwhile, SGB may also help stabilize patients' perioperative hemodynamic indexes, but the result still needs to be supported by further large sample data.

Nano-lipid Contrast Agent Combined with Ultrasound-Guided SGB in Nursing Treatment of Lymphedema after Breast Cancer Surgery.

At present, the application of nano-material technology in nursing treatment is more and more extensive, so the characteristics of a variety of chips tend to the medical field. Lymphedema after breast cancer surgery is common in the recovery period of patients, so the nursing work in this period is very important. In order to explore the effect of nano-lipid contrast agent combined with ultrasound-guided SGB in the nursing treatment of breast cancer postoperative lymphedema, the application scope of nano-lipid contrast agent combined with ultrasound-guided SGB and the promotion of nano-materials on cell growth were studied. 11 cases of breast cancer patients in our hospital in 2020 were selected to study the status of lymphedema in the infection stage and recovery stage. The branching effects of nano-lipid contrast agent and ultrasound-guided SGB were evaluated. The results showed that at the same density, the recovery time of lymph tissue in the nano-lipid contrast agent combined with the ultrasound-guided SGB group was significantly shorter than that in the control group. Due to the self-healing state, the recovery time was the most significant 3-7 days after surgery. At this time, the survival rate of self-healing cells was 34.75%, and that of the nano-lipid contrast agent group was 82.37%, which indicated that the nano-lipid contrast agent combined with ultrasound-guided SGB could effectively play the role of photodynamic therapy and synergistic therapy, and inhibit the growth of tumor cells. At present, many kinds of phototherapeutic agents can inhibit the growth of cancer cells and induce apoptosis of cancer cells. Safe and efficient nano photosensitizers have broad application prospects in the field of cancer treatment.

Interventional Treatment Modalities for Chronic Abdominal and Pelvic Visceral Pain.

PURPOSE OF REVIEW: Chronic abdominal and pelvic visceral pain is an oftentimes difficult to treat pain condition that requires a multidisciplinary approach. This article specifically reviews the interventional treatment options for pain resulting from visceral abdominal and pelvic pain. RECENT FINDINGS: Sympathetic nerve blocks are the main interventional option for the treatment of chronic abdominal and pelvic visceral pain. Initially, nerve blocks are performed, and subsequently, neurolytic injections (alcohol or phenol) are longer term options. This review describes different techniques for sympathetic blockade. Neuromodulation is a potential option via dorsal column stimulation or dorsal root ganglion stimulation. Finally, intrathecal drug delivery is sometimes appropriate for refractory cases. This paper will review interventional options for the treatment of chronic abdominal and pelvic visceral pain.

Sympathetic Blocks for Sympathetic Pain.

The sympathetic nervous system (SNS) is an integral component of the body's response to stress. Once activated, the SNS has broad-reaching effects on multiple organ systems that modulate pain, behavior, and mood. Blockade of the system can improve pain associated with multiple etiologies, including vascular, visceral, and neuropathic pain. Multiple techniques are available to block the SNS and provide options that improve analgesia and can be individualized to a particular patient's needs and disease state.

Sympathetic Blocks for Visceral Pain.

For patients with chronic pain or cancer-related pain, the most common indication for sympathetic block is to control visceral pain arising from malignancies or other alterations of the abdominal and pelvic viscera. When it is recalcitrant to conservative care, or if the patient is intolerant to pharmacotherapy, consideration of sympathetic blocks or neurolytic procedures is considered. Potential advantages of a neurolytic procedure, compared with spinal and epidural anesthetic infusions, include cost savings and avoidance of hardware. Interventional therapies that target afferent visceral innervation via the sympathetic ganglia offer effective and durable analgesia and improve multiple metrics of quality of life.

Continuous Thoracic Paravertebral Block to Treat Electrical Storm.

Continuous ganglion block is increasingly being used to help manage ventricular tachyarrhythmias. We present the cases of 2 patients in whom we used continuous left thoracic paravertebral block to achieve sympathetic denervation and improvement in drug-refractory ventricular tachyarrhythmias. Whether as destination therapy or bridging therapy, we conclude that the block is safe, improves patients' comfort, and is superior in several ways to stellate ganglion block and other single-injection techniques.