Sympathetic blocks for complex regional pain syndrome: a survey of pain physicians

Background: Sympathetic blocks (SB) are commonly used to treat pain from complex regional pain syndrome (CRPS). However, there are currently no guidelines to assist pain physicians in determining the best practices when using and performing these procedures.

Methods: A 32-question survey was developed on how SBs are used and performed to treat CRPS. The survey was conducted online via SurveyMonkey. The responses were statistically analyzed using descriptive statistics, and comparing academic versus non-academic, and fellowship versus non-fellowship-trained physicians.

Results: A total of 248 pain physicians responded with a response rate of 37%. Forty-four percent of respondents schedule the first SB at the first clinic visit; 73% perform one to three consecutive blocks; over 50% will repeat the block if a patient receives at least 50% pain relief from the previous one lasting 1-7 days.Fifty-four percent of respondents perform stellate ganglion blocks (SGB) at the C6 vertebral level, 41% at C7; 53% perform lumbar sympathetic blocks (LSB) at L3 level, 39% at L2; 50% use fluoroscopy to guide SGB, 47% use ultrasound. More respondents from academic than non-academic centers use ultrasound for SGB. About 75% of respondents use a total volume of 5-10 mL for SGB and 10-20 mL for LSB. The most commonly used local anesthetic is 0.25% bupivacaine. About 50% of respondents add other medications, mostly steroids, for these blocks.

Conclusion: Our study showed a wide variation in current practice among pain physicians in treating CRPS with SBs. There is a clear need for evidence-based guidelines on when and how to perform SBs for CRPS.