Analysis of Photoplethysmographic Signal in Lumbar Sympathetic Block

An Analysis of Photoplethysmographic Signal in Diagnostic Lumbar Sympathetic Block for Complex Regional Pain Syndrome

This study aims to compare the alternative current and the direct current signal changes of photoplethysmography between both feet during one side lumbar sympathetic block.

The hypothesis is that signal changes occur earlier than other indices to decide whether it is successful following lumbar sympathetic block on only one-side.

Inclusion Criteria:

• Physically examined for complex regional pain syndrome on lower extremity,
• Scheduled for diagnostic lumbar sympathetic blockade.

Exclusion Criteria:

• Graded as ASA 3 or higher,
• Below 18 or above 70 years of age, or
• Had any other contraindication for regional anesthesia.