CT-Guided Lumbar Sympathectomy: A Palliative Approach for Intractable Ischemic Rest Pain in Chronic Limb-Threatening Ischemia

A 76-year-old woman was referred for severe, chronic bilateral foot pain (left greater than right). Her medical history included advanced dementia (Brief Interview for Mental Status score 3), hypertension, hyperlipidemia, type 2 diabetes (HbA1c 7.7% one year prior), coronary artery disease with prior stenting, and severe peripheral vascular disease. She used a wheelchair due to chronic debilitating bilateral foot pain that worsened when lying flat, especially at night. Notably, she had no history of prior leg or foot wounds. 

The patient’s medical records were only partially available, and neither the patient nor the family were able to provide a reliable account of her surgical history. Due to the patient’s limited mobility, a telehealth consultation was conducted in lieu of an in-person physical examination. 

Approximately 1.5 years prior to consultation, the patient’s ankle-brachial indices were measured at 0.46 on the right and 0.24 on the left. Given her significant comorbidities and frailty, the patient was deemed unsuitable for further revascularization at that time by another department. However, her persistent and severe ischemic pain continued to be a major concern for the patient and her family. A CT angiogram (CTA) was obtained at our institution through another department, with the aim of identifying potential revascularization targets that could alleviate her symptoms. The CTA revealed severe diffuse bilateral vascular disease, including 60% to 70% stenosis of the distal aorta, severe stenosis of the right common femoral artery, occlusion of a right profunda-to-popliteal bypass graft and occluded native right superficial femoral artery, an occluded or severely stenotic right popliteal artery, and 2-vessel runoff to the right foot via the posterior tibial and peroneal arteries (Figures 1 and 2). On the left, there was multifocal mild-to-moderate disease in the common and proximal external iliac arteries, a patent external iliac stent, long-segment occlusion of the left superficial femoral artery, and 2-vessel runoff to the left foot via the posterior tibial and peroneal arteries (Figure 3).

The patient was subsequently referred to our clinic to evaluate potential treatment options. There was significant concern that the patient would tolerate only minimal sedation and limited time on the procedural table due to persistent pain, confusion, and general frailty (American Society of Anesthesiologists class III). However, she had no impending risk of amputation and no active wounds. Considering the nature of her symptoms, her overall risk profile, and the typically short duration of the procedure, the patient was deemed an appropriate candidate for percutaneous CT-guided LS with a concurrent block. After a thorough discussion of the risks and benefits with the patient and her family, the patient was scheduled for the procedure. On preprocedural examination, her feet were cool to the touch, painful, and difficult to move (left worse than right). Monophasic Doppler signals were present in each dorsalis pedis artery. No detectable signal was present over the bilateral posterior tibial arteries. 

In brief, the procedure was initiated by obtaining intravenous access to provide moderate sedation. The patient was placed prone in the CT scanner (Brilliance iCT 256 [Phillips]). Minimal procedural medications were administered: two 25-µg doses of intravenous fentanyl and 4 mg of intravenous ondansetron. Initial CT (3-mm width slices) images were obtained from the diaphragm to the pelvis. The access site was cleaned and prepped under sterile conditions, and 1% lidocaine was used for subcutaneous anesthesia in the paralumbar region. Access sites were chosen that provided a safe path to the bilaterally lumbar sympathetic chains at the L2/L3 level. An oblique needle path was required to avoid vital structures.

Under intermittent CT guidance, two 22G needles were advanced lateral to the iliopsoas muscles until the tips were immediately adjacent to the sympathetic chains. Needle placement was confirmed by an inability to aspirate blood and by a test injection of 4 cc of a 10% contrast (Omnipaque 350 [GE Healthcare]) saline mixture, which confirmed spread around the bilateral sympathetic chains. Subsequently, 2.5 mL of 99% ethanol was administered on each side, with a dwell time of 3 minutes. This was followed by an injection of a mixture containing 3 mL of betamethasone acetate/betamethasone sodium phosphate (Celestone Soluspan), 4 mL of 0.5% of bupivacaine, and 1 mL of Omnipaque 350 contrast, which diluted the original ethanol injection. Post-injection CT imaging confirmed that the solution surrounded the bilateral lumbar sympathetic chains (Figure 4). The patient tolerated the procedure well without any complaints of pain or changes in vital signs. She was transported to the recovery area without complications. Total procedure time was 21 minutes; administered radiation was DLP1499 mGy.cm, CTDIvol 16.3 mGy.

Shortly after the procedure, both feet were noted to be warm and pain-free, with noticeably improved mobility. The patient was held in observation for 3 hours post-procedure and then discharged without complaints. At her 2- and 4-month follow-up visits, her family reported she was no longer complaining of foot pain and showed some improvement in her ability to engage in physical therapy and ambulate. The patient passed away shortly after the 4-month follow-up due to unrelated causes; however, her family emphasized that she never complained of foot pain after this procedure.