Regional Sympathetic Block Research Articles

Raquianestesia total após bloqueio de gânglio estrelado em paciente com síndrome dolorosa complexa regional: relato de caso

JUSTIFICATIVA E OBJETIVOS: A síndrome dolorosa complexa regional (SDCR) é uma síndrome dolorosa debilitante, com prevalência elevada em serviços de tratamento de dor. Apresenta diversas opções terapêuticas, sendo o bloqueio regional simpático uma das mais efetivas. O objetivo deste estudo foi relatar a intercorrência incomum do bloqueio de gânglio estrelado em paciente portadora de SDCR no membro superior direito. RELATO DO CASO: Paciente do sexo feminino, 49 anos, estado físico ASA I, admitida para tratamento de dor no ombro superior direito de forte intensidade, em queimação, associada a mudanças tróficas, após oito meses de traumatismo local. Diagnosticada com SDCR, indicou-se bloqueio simpático em gânglio estrelado. Após monitorização realizou-se bloqueio com bupivacaína a 0,5% (8 mL), evoluindo, após injeção em topografia de gânglio estrelado por abordagem paratraqueal, com parestesia de membros distal, ansiedade e taquidispneia importante. Imediatamente a paciente foi sedada e realizada intubação orotraqueal, permanecendo em observação por 135 minutos. Recuperada, foi levada para a sala de recuperação pós-anestésica (SRPA). Após três dias do procedimento, relatou redução de dor na escala visual analógica, de 10 para 3 pontos. CONCLUSÃO: Bloqueios regionais já demonstraram eficácia elevada no tratamento de quadros dolorosos vários, incluindo a SDCR. Este caso demonstrou que, apesar de serem incomuns, efeitos indesejáveis podem ocorrer, e o anestesiologista deve estar preparado para o suporte adequado do paciente nessas situações. O conhecimento adequado da anatomia e da técnica anestésica reduz a ocorrência desses efeitos.

Therapie akraler Nekrosen bei MCTD: Kombination von Iloprost, hyperbarer Oxygenation und regionaler Sympathikolyse – ein Fallbericht

In patients with systemic sclerosis or mixed connective tissue disease (MCTD) acral ulcers are considered as frequent manifestations that may lead to amputation and loss of function, respectively, as a result of secondary Raynaud's phenomenon. Thus it is necessary to take advantage of all available medical and supportive measures. Adjuvant treatments such as hyperbaric oxygenation and regional sympathetic block represent interdisciplinary treatment options to improve oxygenation of critical ischemia and analgesia and should be subject of further investigation.

An Effective Case of Intravenous Regional Sympathetic Block Under Continuous Prostaglandin E1 Intravenous Infusion for Refractory Ulcerative Pain in the Right Big Toe of a Patient with Progressive Systemic Sclerosis

An Effective Case of Intravenous Regional Sympathetic Block Under Continuous Prostaglandin E1 Intravenous Infusion for Refractory Ulcerative Pain in the Right Big Toe of a Patient with Progressive Systemic Sclerosis

A case of complex regional pain syndrome type II associated with the adverse effect by intravenous regional sympathetic block with reserpine

A case of complex regional pain syndrome type II associated with the adverse effect by intravenous regional sympathetic block with reserpine

Hepatic Effects of Thoracic Epidural Analgesia in Experimental Severe Acute Pancreatitis

Thoracic epidural anesthesia (TEA) protects the intestinal microcirculation and improves perioperative outcomes. TEA also reduces mortality in acute experimental pancreatitis. Its impact on hepatic microcirculation, however, in health and critical illness is unknown. Therefore, the authors studied the effect of TEA on the liver in healthy rats and in experimental severe acute pancreatitis. TEA was induced by 15 microl/h bupivacaine, 0.5%. Necrotizing pancreatitis was induced by intraductal infusion of 2 ml/kg taurocholic acid, 5%. Twenty-eight rats were assigned to either Sham operation, Sham + TEA, Pancreatitis, or Pancreatitis + TEA. After 15 h, mean arterial pressure, heart rate, and respiratory function were recorded. Sinusoidal width and perfusion rate and the intrahepatic leukocyte adhesion were assessed by intravital microscopy. In an additional 22 rats randomly assigned to Sham, Pancreatitis, and Pancreatitis + TEA, hepatic apoptosis was evaluated by staining for single-stranded DNA and Fas ligand-positive cells. TEA did not affect hepatic microcirculation and leukocyte adhesion in healthy rats. Blood pressure remained unchanged in the Sham + TEA group. In Pancreatitis, mean arterial pressure decreased from 141 + or - 6 mmHg to 127 + or - 13 mmHg but remained stable in Pancreatitis + TEA. The sinusoidal diameter decreased from 5.4 + or - 0.1 microm to 5.0 + or - 0.2 microm in Pancreatitis. This was restored in Pancreatitis + TEA. Intrahepatic leukocyte adhesion was not affected by TEA. The increased hepatocyte apoptosis in Pancreatitis was abolished in Pancreatitis + TEA. This might be mediated by inhibition of the Fas ligand pathway. TEA reduces liver injury in necrotizing acute pancreatitis. This could be related to a regional sympathetic block. TEA could thus preserve liver function in systemic inflammatory disorders such as acute pancreatitis.

Thoracic epidural anesthesia reverses sepsis-induced hepatic hyperperfusion and reduces leukocyte adhesion in septic rats

IntroductionLiver dysfunction is a common feature of severe sepsis and is associated with a poor outcome. Both liver perfusion and hepatic inflammatory response in sepsis might be affected by sympathetic nerve activity. However, the effects of thoracic epidural anesthesia (TEA), which is associated with regional sympathetic block, on septic liver injury are unknown. Therefore, we investigated hepatic microcirculation and inflammatory response during TEA in septic rats.MethodsForty-five male Sprague-Dawley-rats were instrumented with thoracic epidural catheters and randomized to receive a sham procedure (Sham), cecal ligation and puncture (CLP) without epidural anesthesia (Sepsis) and CLP with epidural infusion of 15 ul/h bupivacaine 0.5% (Sepsis + TEA). All animals received 2 ml/100 g/h NaCl 0.9%. In 24 (n = 8 in each group) rats, sinusoidal diameter, loss of sinusoidal perfusion and sinusoidal blood flow as well as temporary and permanent leukocyte adhesion to sinusoidal and venolar endothelium were recorded by intravital microscopy after 24 hours. In 21 (n = 7 in each group) separate rats, cardiac output was measured by thermodilution. Blood pressure, heart rate, serum transaminase activity, serum TNF-alpha concentration and histologic signs of tissue injury were recorded.ResultsWhereas cardiac output remained constant in all groups, sinusoidal blood flow increased in the Sepsis group and was normalized in rats subjected to sepsis and TEA. Sepsis-induced sinusoidal vasoconstriction was not ameliorated by TEA. In the Sepsis + TEA group, the increase in temporary venolar leukocyte adherence was blunted. In contrast to this, sinusoidal leukocyte adherence was not ameliorated in the Sepsis + TEA group. Sepsis-related release of TNF-alpha and liver tissue injury were not affected by Sepsis + TEA.ConclusionsThis study demonstrates that TEA reverses sepsis-induced alterations in hepatic perfusion and ameliorates hepatic leukocyte recruitment in sepsis.

Pharmacotherapy options for complex regional pain syndrome

Complex regional pain syndrome is a painful disorder of unclear etiology, typically involving the distal part of one limb, represented by spontaneous and evoked pain as well as autonomic, motor and trophic abnormalities. It can be incapacitating and severely affect function and quality of life. Although full-blown complex regional pain syndrome can be diagnosed easily, less fulminate forms of the syndrome often remain undiagnosed. Controlled trials have demonstrated that a short course of oral corticosteroids, intranasal or intramuscular calcitonin, intravenous bisphosphonates, free-radical scavengers, gabapentin, regional intravenous sympathetic blocks with bretylium and spinal cord stimulation or physical therapy and occupational therapy can be efficacious for complex regional pain syndrome. Nonetheless, the management of this syndrome is difficult because currently available drugs and technologies do not provide adequate pain relief for a considerable percentage of sufferers. The present review focuses primarily on the pharmacotherapy of complex regional pain syndrome and describes briefly the epidemiology, pathogenesis and clinical manifestations of the syndrome.

Regional sympathetic blockade unmasks potent vasodilation during hypoxia in sleep apnea

Obstructive sleep apnea (OSA) is associated with excessive sympathetic activity, endothelial dysfunction and premature cardiovascular disease. To test the hypothesis that increased sympathetic activity in OSA might attenuate hypoxia-induced skeletal muscle vasodilation, we determined forearm blood flow (FBF, brachial artery) and vascular conductance (FVC) during systemic hypoxia (FiO2 0.1; 10 min) before and after regional sympathetic block in OSA (n=10) and weight- and age-matched controls (n=10). FBF was determined by ultrasound/Doppler and FVC was calculated as FBF/mean arterial pressure. Regional sympathetic block was achieved via Bier block with the α-receptor antagonist phentolamine. Pre phentolamine, during hypoxia (SaO2 79±1%), similar increases in FBF and FVC were noted in the 2 groups. Post phentolamine, the FBF and FVC responses to systemic hypoxia were markedly enhanced (control pre vs. post: 62±80 vs. 140±26 ml/min, P<0.01; and 0.58±0.07 vs. 1.30±0.24 units, P<0.01; OSA pre vs. post: 76±11 vs. 208±37 ml/min, P<0.002; and 0.71±0.11 vs. 1.83±0.31 units, P<0.002). However, following regional sympathetic block, FBF and FVC during hypoxia and the percent increase of FBF and FVC from baseline were not significantly different in the 2 groups (P=NS). We conclude that, despite the previously reported increased sympathetic activity in OSA, the ability to vasodilate during hypoxia is preserved, and, regional sympathetic block unmasks powerful vasodilator effects of hypoxia in OSA. This suggests that in OSA skeletal muscle metabolic vasodilator pathways may be up-regulated and act to offset the increased sympathetic vasoconstrictor nerve activity. Supported by R01 HL068699, P01 HL077670, M01 RR010732.

A case of recurrent and migratory complex regional pain syndrome type I: prevention by gabapentin

Complex regional pain syndrome type I (CRPS I) or reflex sympathetic dystrophy (RSD) is a painful and disabling neuropathic pain syndrome. We report a case of a patient who has experienced CRPS I four times with an unidentified cause for all recurrences. The patient responded well to a combination of physiotherapy and intravenous regional sympathetic block in the first two attacks, but not in the fourth one. Gabapentin was effective in the last two attacks. Gabapentin was gradually discontinued 12 months after the last attack and no other recurrence was observed for a follow-up period of 9 months. This case suggests that gabapentin might be considered in the treatment and prevention of CRPS I.

Treatment of complex regional pain syndrome type I of the hand with a series of intravenous regional sympathetic blocks with guanethidine and lidocaine

The aim of this study was to evaluate the efficacy of guanethidine and lidocaine in the treatment of complex regional pain syndrome (CRPS) type I of the hand. Seventeen patients, aged between 33 and 72 years, suffering from CRPS type I of the hand received two series of intravenous regional sympathetic block (Bier's block) sessions with guanethidine and lidocaine according to the following therapeutic protocol: (1) 5 sessions (once every second day) composed of intravenous regional administration of 15 mg guanethidine and 1 mg lidocaine/kg body weight each and (2) 20 sessions (twice a week) composed of intravenous regional administration of 10 mg guanethidine and 1 mg lidocaine/kg body weight each. Complete disappearance of pain and return of the normal function and movement of the extremity were achieved. No side effects were observed. The above-described therapeutic protocol method resulted in excellent pain relief and full restoration of both function and range of movement of the affected extremity in 17 patients suffering from CRPS type I of the hand.

Effects of stellate ganglion block on cerebral haemodynamics as assessed by transcranial Doppler ultrasonography

Stellate ganglion block (SGB) causes vasodilatation in the skin of the head and neck because of regional sympathetic block. Its effects on cerebral haemodynamics, in health or in disease, are not clear. We evaluated the effects of SGB on ipsilateral middle cerebral artery flow velocity (MCAFV), estimated cerebral perfusion pressure (eCPP), zero flow pressure (ZFP), carbon dioxide reactivity (CO2R) and cerebral autoregulation using transcranial Doppler ultrasonography (TCD). Twenty male patients, with pre-existing brachial plexus injury, and undergoing SGB for the treatment of complex regional pain syndrome of the upper limb, were studied. For SGB, 10 ml of plain lidocaine 2% was used and the onset of block was confirmed by presence of ipsilateral Horner's syndrome. The MCAFV, eCPP, ZFP, CO2R, and cerebral autoregulation were assessed before and after SGB using established TCD methods. The changes in these variables were analysed using Wilcoxon's signed rank test. The block caused a significant decrease in MCAFV from median (inter-quartile range) value of 61 (53, 67) to 55 (46, 60) cm s(-1), a significant increase in eCPP from 59 (51, 67) to 70 (60, 78) mm Hg, and a significant decrease in ZFP from 32 (26, 39) to 25 (16, 30) mm Hg. There were no significant changes in CO2R or cerebral autoregulation. The increase in eCPP, decrease in ZFP, and no changes in CO2R or cerebral autoregulation suggest that the SGB decreases cerebral vascular tone without affecting the capacity of the vessels to autoregulate. These effects may be of therapeutic advantage in relieving cerebral vasospasm in certain clinical settings.

Role of the sympathetic nervous system in pain

Some chronic pain conditions appear to be sympathetically mediated because interruption of the sympathetic supply results in pain relief. Examples include: complex regional pain syndrome type I and II; visceral pain due to abdominal and pelvic cancers; ischaemic pain or tissue viability from peripheral vascular disease, arterial spasm or frostbite; ischaemic heart disease; post-herpetic neuralgia; erythromelalgia. The sympathetic ganglion can be blocked at several locations. The stellate (cervicothoracic) ganglion can be blocked to reduce pain in the head and upper limb. The lumbar sympathetic chain can be blocked to reduce pain in the lower limb, and the thoracic sympathetic chain to block thoracic pain. The coeliac plexus can be blocked to reduce pain in the upper gastrointestinal tract (e.g. pancreas, liver cancer). The superior hypogastric can be blocked to reduce pain in the pelvic area (e.g. bladder, uterine cancer). Ganglion impar can be blocked to reduce perineal pain such as pelvic floor cancer. Blocks are usually performed using local anaesthetic, preferably a long acting one to maximize duration of effect. Neurolytic blocks can also be carried out using phenol (6% or ethanol 50–100%), most commonly with coeliac and lumbar sympathectomy. An intravenous regional sympathetic block (Bier's block with guanethidine) can be carried out to reduce pain in the upper and lower limb. Guanethidine is injected into an occluded vein, where it is absorbed into the perivascular sympathetic plexus and induces release of noradrenaline. It then prevents the reabsorption of noradrenaline by being preferentially absorbed into the sympathetic nerve itself, so depleting the vesicles of transmitter. A systemic infusion of phentolamine (alpha antagonist) can be used for diagnosis.

Intravenous regional sympathetic block: past, present and future?

Intravenous regional sympathetic block is a valued component of the pain clinician's armamentarium for the management of the complex regional pain syndrome type 1. Treatment of this multifaceted condition is multimodal, and despite a lack of convincing supporting evidence from clinical trials, the author makes the case for retaining the technique while recommending both appropriate guidance and further study.

Complex regional pain syndrome I and II. What effects the outcome?

The results of clinical studies have raised doubts on the effectiveness of regional sympathetic blocks with guanethidine (IVRSB) in patients suffering from complex regional pain syndrome (CRPS). We conducted a retrospective analysis of long-term results in our patients and searched for possible factors predicting long-term outcome after IVRSB: After approval by our ethics commission and written informed consent, 42/44 patients were included. We documented diagnosis, history, therapy and long-term result from charts. Long-term results were also obtained from a questionnaire administered to the patients. These were defined as very good (reduction of pain > or =75%), good (pain reduction <75% and > or =50%), moderate (pain reduction <50% and > or =25%) or poor (pain reduction <25%). The association of a moderate or poor outcome with the factors age, gender, duration of time until therapy, pain intensity before therapy, dose of applied guanethidine and duration of therapy was calculated by odds ratio. Confidence intervals for the odds ratios were determined by Woolfs approximation. After a mean duration of 18 months, the outcome was classified as very good in 14, good in 13, moderate in 5 and poor in 10 patients. An increased rate of moderate or poor outcome was associated with age<60 years (OR=4.00, CI 1.04-15.26), male gender (OR=2.93, CI 0.71-12.11) and duration of therapy>2 weeks (OR=3.27, CI 0.86-12.36). The factors duration of time until therapy, initial pain intensity and total dose of guanethidine were not associated with increased rates of moderate or poor outcome. We only seldom observed a complete functional restoration after CRPS. Male patients <60 years showed an increased risk of developing chronic pain. It remains unclear whether the risk of chronic pain reflects different responses to therapy or differences in the natural course of the disease in our patients. A meta-analysis of randomised trials of IVRSB in CRPS failed to prove the effectiveness of this intervention. If other investigations confirm our impression, future studies of CRPS-treatments should be planned and analysed with regard to the possible influence of the natural course and different risks of chronic pain among patients with CRPS.

Clinical management of the child with chronic pain

Clinical management of the child with chronic pain

REGIONAL INTRAVENOUS SYMPATHETIC NERVE BLOCKS

The assessment of the possible efficacy of regional intravenous blocks or sympathetic blocks, in general, raises a number of questions that may be answered after studying the techniques of regional pharmacologic segmental blocks and their effects on the sympathetic system. The authors present an original clinical study evaluating the capacity of regional intravenous guanethidine to induce a sympathetic blockade compared with other techniques.

Dysesthetic pain in patients with syringomyelia.

Dysesthethic pain is a common complaint of patients with syringomyelia, traumatic paraplegia, and various myelopathic conditions. Because cavitary lesions of the spinal cord can be defined with good resolution by magnetic resonance imaging, syringomyelia provides a potential model for examining anatomic correlates of central pain. In this study, a syndrome of segmental dysesthesias, characterized by burning pain, hyperesthesia, and a variable incidence of trophic changes, was described by 51 of 137 patients (37%) with syringomyelia at the time of clinical presentation. Complete magnetic resonance scans, including axial images, demonstrated extension of the syrinx into the dorsolateral quadrant of the spinal cord on the same side and at the level of pain in 43 of 51 patients (84%). Surgical treatment of syringomyelia resulted in the relief or improvement of dysesthetic pain in 22 of 37 patients (59%), but 15 patients (41%) reported no improvement or an intensification of pain despite collapse of the syrinx. Postoperative dysesthetic pain was often a disabling complaint that responded poorly to medical therapy, including analgesics, sedatives, antiepileptics, antispasmodics, and anti-inflammatory agents. In most cases, there was a gradual improvement of symptoms, although six patients continued to complain of pain 24 to 74 months postoperatively. Prompt but transient relief was achieved in two of two patients with regional sympathetic blocks, and prolonged relief was achieved in one patient by stellate ganglionectomy. We conclude that painful dysesthesias can be caused by a disturbance of pain-modulating centers in the dorsolateral quadrant of the spinal cord and have certain causalgia-like features that respond in an unpredictable way to surgical collapse of the syrinx.

Intravenous regional sympathetic blockade for pain relief in reflex sympathetic dystrophy: A systematic review and a randomized, double-blind crossover study

The first aim was a systematic review of intravenous regional sympathetic blocks (IRSBs) in patients with reflex sympathetic dystrophy (RSD). Randomized controlled trials (RCTs) of IRSBs in patients with RSD were identified by MEDLINE search (1966 to May 1993) and by hand search of 30 journals (1950 to May 1993). Authors of eligible trials were asked for information on additional trials and for unpublished data. Seven RCTs of IRSBs in RSD were found. Four used guanethidine; none showed significant analgesic effect in IRSBs to relieve pain due to RSD. Two reports, one using ketanserin and one bretylium, with 17 patients in total, showed some advantage of IRSBs over control. RCT results were not combined because of the variety of different drugs and outcome measures and because of methodological deficiencies in most of the reports. The second aim was a randomized, double-blind, crossover study to assess the effectiveness of IRSBs with guanethidine. Patients fulfilling diagnostic criteria for RSD and who had reported pain relief after an open IRSB with guanethidine received IRSBs with guanethidine high dose, guanethidine low dose, and normal saline. Pain intensity and relief, adverse effects, mood, duration of analgesia, and global scores were recorded. Sixteen patients with diagnosis of RSD were recruited, but only nine entered the double-blind phase. The trial was stopped prematurely because of the severity of the adverse effects. No significant difference was found between guanethidine and placebo on any of the outcome measures. Patients in all groups reported less than 30% of the maximum possible relief during the first week after the injections, and on only two occasions (one saline and one guanethidine low dose) was relief reported for longer than a week. There was no evidence of a dose response for guanethidine. The use of guanethidine in IRSBs for patients with RSD was not supported by the systematic review or by the double-blind study.

Intravenous Regional Sympathetic Block with Labetabol for Reflex Sympathetic Dystrophy (R.S.D.)

Intravenous Regional Sympathetic Block with Labetabol for Reflex Sympathetic Dystrophy (R.S.D.)

An unusual case of causalgia. Relevance to recent hypothesis on mechanism of causalgia

Intravenous regional sympathetic block with guanethidine caused only limited improvement in a patient with longstanding causalgia. Lumbar sympathetic block with phenol also had little direct effect on the pain but completely abolished associated allodynia and vasomotor signs. Following sympathectomy the response to subsequent guanethidine blocks was enhanced. This improvement persisted even after 8 months when there was some return of the previous allodynia and vasomotor signs (to involve a smaller area than previously). The case would appear to have implications for a recently proposed hypothesis concerning the mechanism of pain in causalgia.