Ureteropelvic damage is the most frequently reported serious complication of conventional chemical lumbar sympathectomy or CLS. Although it is relatively rare, it is very harmful to patients. This protocol aids in the precise delivery of the activating agents behind the anterior fascia of the psoas major muscle, allowing selective targeting of gray rami communicantes, thus the safety of CLS can be largely improved.
Before initiating the treatment procedure, confirm the presence of indications and lack of contraindications based on the patient's clinical and laboratory results. Disinfect an approximately 30 centimeter area of skin two times at the planned needle puncture site with 2%entoiodine and cover the patient's back with surgical towels. Using lateral thoroscopy guidance, anesthetize the skin and the entire needle tract with 5-8 milliliters of 0.5%lidocaine without vasoconstrictors, advancing the needle to the vertebral body surface gradually.
Position the needle tip in the optimal injection area by using lateral view lumbar x-ray. Then, inject 0.5 milliliters of contrast agent to confirm the needle tip is behind the anterior fascia of the psoas muscle. If the contrast agent remains mainly confined to the optimal area with spreading along the psoas major muscle, the needle placement was successful.
Inject 2 milliliters of 5%aqueous phenol solution into the injection site, adjusting the needle tip direction to ensure that 1 milliliter of phenol spreads toward the patient's head and that 1 milliliter spreads toward the patient's feet. When the phenol has been injected, withdraw the needle from the skin and compress and cover the puncture site with gauze to achieve hemostasis. Five minutes after the injection, confirm a satisfactory sympathetic interruption as a rise of at least 2 degrees Celsius in skin temperature.
If satisfactory interruption is not achieved, perform a supplemental injection to another optimal area with a total phenol volume of no larger than 10 milliliters in one day. Measure the patient's skin temperature again, calculating the average among the temperature increases in the shin, plantar, and dorsal foot. Before injecting the phenol solution, confirm that the needle tip is located within the optimal area.
In selective CLS, the contrast agent is injected behind the anterior fascia of the psoas major muscle, targeting the gray rami communicantes. The expected clinical effects are vasodilation, sweat reduction, and pain relief. A precise placement of the needle tip and evaluation of the contrast agent spreading are critical for ensuring an accurate targeting of the gray rami communicantes in CLS treatment.
With selective CLS, the risk of operation is largely reduced, so the indications for CLS could be widened.
