Ask Dr. Z

We are doing large volume blood patches with our neurointerventional doc in the cath lab. These are patients with an unknown leak location or multiple leaks, or who have had a standard blood patch that provided only temporary relief. He puts a small sheath (4F) into the epidural space at the lumbar spine, threads a diagnostic catheter in, and goes all the way up to the cervical spine, and under fluoro starts slowly pulling back the diagnostic catheter while infusing a large amount of the patient's blood that we draw right before the infusion. He infuses about 100 cc of blood all the way from the cervical spine to lumbar spine. Myelography is also performed. Procedure time is approximately 1 hour 15 minutes. Sedation is managed by an anesthesiologist. How would you code these? Standard blood patch (62273)? Therapeutic infusion (62321/62323)? Unlisted code?