Lumbar Sympatholysis - An Overview

Introduction

Lumbar sympatholysis is performed to interfere with the sympathetic nerves in the lumbar area of the spine (usually L2 to L4). It is used to treat chronic pain issues, especially those that involve the lower extremities. It involves various methods to stop sympathetic nerve transmission, including chemical neurolysis and surgical methods (rarely used). Peripheral vascular disease (a slowly deteriorating circulation condition brought on by blockages or narrowing) and complex regional pain syndrome (CRPS) (discomfort that typically impacts the arm or leg) are two conditions for which lumbar sympatholysis can offer long-term relief. The benefits of lumbar sympatholysis might not last. Therefore, it is crucial to understand that additional treatments might be necessary for comfort from long-term pain.

It is critical to distinguish between a lumbar sympathetic block and lumbar sympatholysis. By employing methods other than local anesthetics, lumbar sympatholysis attempts to permanently or over time block the sympathetic chain's transmission to the lower extremities. On the other hand, a lumbar sympathetic block uses mostly local anesthetics. It is frequently used as a diagnostic procedure to evaluate a candidate's response before pursuing longer-term care, such as lumbar sympatholysis.

What Are the Indications of Lumbar Sympatholysis?

• Many illnesses of the lower extremities, including postherpetic neuralgia (chronic pain in the skin regions affected by shingles), phantom limb pain (experience of discomfort or pain in a limb that is missing), and complex regional pain syndrome (CRPS) are treated with lumbar sympatholysis.

• Patients with severe ischemic rest discomfort and peripheral artery disease that is considered irreversible have also benefited from lumbar sympathetic neurolysis.

• It has also demonstrated potential in treating chronic visceral pain associated with incurable cancers of the kidney, bladder, ovaries, descending colon, and upper sigmoid colon.

• Lumbar sympatholysis also treats plantar hyperhidrosis (excessive perspiration on the foot soles).

What Are the Contraindications of Lumbar Sympatholysis?

• An infection at the operation site and the lack of informed consent are strong contraindications to lumbar sympathetic neurolysis.

• Other contraindications include blood dyscrasias (conditions affecting the bone marrow, platelets, and lymph tissue) such as platelet dysfunctions (platelets not working properly), malignancy near the treatment site, systemic infection, coagulation abnormalities, bacteremia (presence of bacteria in the blood), and severe heart or lung disease.

How Is Lumbar Sympatholysis Performed?

Lumbar sympatholysis aims to reduce pain and dysfunction brought on by sympathetic nervous system activity. This can be accomplished using various techniques, such as radiofrequency ablation (RF), chemical neurolytic agents or medications, and, in rare cases, surgery.

• Patient Preparation:

  • Fluoroscopy facilitates sympathectomy procedures by making injected contrast material visible and assisting the physician in locating bone landmarks. With monitors attached, patients are positioned prone on the fluoroscopy bed. It is possible to provide anxiolytic medications. Antibiotics as a preventive measure are usually not necessary. A surgical time-out is carried out to confirm the patient's identification, technique, and site. Sterile procedures are used to prepare the lumbar area. Targeted areas in L2-L4 are identified by fluoroscopy in a posterolateral oblique projection. At the location of needle entry, local anesthetic is applied as needed. To assess the effectiveness of a successful sympathetic blockade, cutaneous temperature is typically measured at both lower extremities before and after.

• Chemical Neurolysis - Chemical neurolysis is a pain management technique that involves injecting a neurolytic substance, like alcohol or phenol, into particular nerves to cause dysfunction. For ailments like persistent back pain or discomfort associated with cancer, the anterolateral side of the vertebral body is frequently the target location.

  • To perform chemical neurolysis, a 15 cm (centimeter) or 5.90-inch needle with a gauge of 20 to 22 is inserted beneath the transverse process, approximately seven cm or 2.75 inches to the side of the midline.

  • The needle is moved toward the vertebral body's anterior border using fluoroscopy, occasionally into the perivertebral space.

  • Three to five mL (milliliter) of Bupivacaine 0.5 percent are administered after contrast material has been injected and properly disseminated to achieve nerve root anesthesia. After that, about five mL of the selected neurolytic agent—such as phenol or alcohol—is injected. All levels are verified and aspirated before administering the neuroleptic drug when using a multi-needle technique.

  • Depending on the availability and condition of the patient, practitioners may switch up the injectables.

  • A three-needle method is more effective and needs less neurolytic drug volume.

• Radiofrequency (RF) Thermocoagulation:

  • Radiofrequency (RF) thermocoagulation, often known as RF ablation, is a percutaneous technique that can potentially result in denervation. Though thermocoagulation (heat-induced tissue coagulation during surgery) is carried out at the anatomical targets using specialist needles and radiofrequency probes, the targets are comparable. When a high-frequency current is applied to neural tissue via a radiofrequency lesion generator in a closed circuit, it causes neurolysis (applying chemicals or physical agents to a nerve to damage the targeted nerve fibers temporarily). Tissue temperature, electrode size, and lesion length are significant factors that influence the RF ablation process.

• Surgical:

  • The sympathetic chain is often severed or clipped in various surgical techniques. This treatment is usually performed at or below L2 to reduce difficulties and adverse effects associated with sexual dysfunction.

  • Adverse effects associated with sexual dysfunction are more common when performed at higher levels, including the thoracic area.

  • It is important to emphasize that lumbar sympatholysis is a transient phenomenon.

  • While neurolytic or interventional radiofrequency methods usually offer relief for up to six months until nerve regeneration takes place, surgical lumbar sympatholysis may have effects that continue for several years.

What Are the Clinical Implications of Lumbar Sympatholysis?

For patients suffering from complicated regional pain syndrome, post-herpetic neuralgia, inoperable peripheral artery disease, phantom limb pain, erythromelalgia (a rare disease condition that primarily affects the extremities and is characterized by erythema, warmth, and persistent burning pain), and hyperhidrosis (heavy perspiration unrelated to heat or exertion), lumbar sympatholytic provides efficient relief from chronic, intractable lower extremity pain. The lumbar sympathetic chain is destroyed via radiofrequency thermocoagulation, chemical neurolysis, or surgical sympathectomy techniques during this process. The consequent improvement in symptoms may continue for several years. To guarantee that patients suffering from these debilitating conditions receive safe and effective therapy, healthcare personnel should be well-versed in these techniques and grasp their indications, contraindications, potential side effects, and problems.

What Are the Complications of Lumbar Sympatholysis?

The following are possible complications of lumbar sympatholytic:

• Bleeding.

• Infection.

• Nerve root injury.

Genitofemoral Neuralgia - After chemical lumbar sympatholysis and sympathectomy, the most frequent complication is genitofemoral neuralgia (chronic neuropathic pain in the groin, localized along the genitofemoral nerve's distribution), which occurs five to seven percent of the time. Certain data indicate that the incidence is higher when alcohol is used in place of phenol. The symptoms are usually temporary and go away in four to six weeks. By avoiding injecting drugs into the psoas muscle, the incidence of genitofemoral neuralgia can be decreased. This is especially true at levels L3 and L4, where intramuscular injection is more frequently used.

Neuraxial Injection - Accidental neuraxial injections (injections given around the central nervous system region) can result in severe outcomes, including complete spinal cord damage or even death. Intrathecal injections (injecting medications into the spinal canal or subarachnoid space allows the substance to enter the cerebrospinal fluid, where it can be used for pain relief, chemotherapy, or spinal anesthesia) of chemical neurolytic drugs have been observed to result in temporary weakness and paralysis, as well as permanent cases.

Intravascular Injection - Accidental intravascular injection of neurolytic drugs into blood arteries near the spine may occur, potentially resulting in toxicity or ischemia (reduced blood flow) of the spinal cord.

• Injury to the nerve root.

Conclusion

Although lumbar sympatholysis is useful in the treatment of persistent pain in the lower extremities, it has dangers that include death or paralysis; thus, patients must be carefully chosen and undergo an interdisciplinary review before the procedure. Comprehensive patient assessment requires communication across medical disciplines. To improve results and reduce risks, healthcare professionals doing the surgery must be well-versed in anatomy, physiology, and technique variations. Patients must be educated about these factors for the best possible treatment outcomes and informed decision-making.