A Pilot Clinical Trial of Sympathetic Blockade With Botulinum Toxin Type A to Treat Complex Regional Pain Syndrome (CRPS): a Randomized, Double-Blind, Controlled, Crossover Trial.
Condition: Pain
MeSH terms: Complex Regional Pain Syndromes; Reflex Sympathetic Dystrophy
Study type: Interventional

Summary: 
      Lumbar sympathetic blocks are part of the standard of care for treating patients with
      sympathetically-maintained pain (e.g. in complex regional pain syndrome or reflex sympathetic
      dystrophy- RSD). In these patients lower extremity pain can be reduced or abolished
      temporarily by blocking sympathetic nerves by doing a lumbar sympathetic block. Patients who
      respond only transiently to sympathetic blocks often choose between potentially dangerous
      lumbar sympathetic block with neurolytic agents, surgical sympathectomy, continued severe
      refractory debilitating pain or other risky invasive surgical procedures such as spinal cord
      electrical stimulation.. It is hypothesized that Botulinum Toxin Type A (BTA) injected in a
      lumbar sympathetic block can provide extended sympathetic blockade and thus pain relief. This
      pilot study aims to see if BTA can be used safely in lower extremity sympathetic blocks, and
      might be useful in providing prolonged pain relief.
    

Detailed description: 
      Lumbar sympathetic block will be performed twice on each patient: once as in the standard of
      practice with 10 cc 0.5% Bupivicaine and once with 75 units of Botox in 10cc of 0.5%
      Bupivicaine. These will be done in random order and the investigator and the patient will be
      blinded to which medicine they received. Two weeks after their pain has returned to 75% of
      their baseline they will receive the second of the blocks.

      Lumbar sympathetic blockade in the standard fashion is accomplished by placing an IV in the
      patient. The patient is then placed face down on a fluoroscopy table. They are then prepped
      and draped in a sterile fashion. Conscious sedation is provided with versed and Fentanyl in
      the operating room with monitoring of blood pressure, pulse oximetry, and ekg. The skin is
      topicalized with one cc of 1% Lidocaine. The L2 lumbar vertebral body is identified and under
      fluoroscopic guidance a 22 gauge 6 inch spinal needle is placed at the anterolateral border
      of the L2 vertebral body. The retroperitoneal space is identified with a loss of resistance
      technique. Correct needle positioned is confirmed radiographically and appropriate spread of
      medications is verified by injecting 3 cc of radio opaque contrast material. The needle will
      be aspirated to verify that it is not intravascular. Ten cc of Bupivicaine 0.5% will then be
      injected in divided dose to ensure safety. Between injections the patient will be asked to
      report ringing in the ears or tingling in the mouth.

      Subjects will be given a form asking them to rate their pain (from 0 to 10 where 0 is no pain
      and 10 is worst pain imaginable) at noon every day starting one week before the injection and
      continuing until they feel there pain has returned to baseline or two weeks whichever is
      longer. Days of analgesia will be the primary endpoint of the study.
    

Intervention name(s): Lumbar sympathetic block with Botulinum Toxin type A
Intervention type(s): Procedure
Intervention MeSH terms: Botulinum Toxins; Botulinum Toxins, Type A; abobotulinumtoxinA
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Double
Primary purpose: Treatment