This procedure is sometimes termed a laminectomy and is often done in combination with a discectomy (which has all the same anesthetic implications) Keep the patient motionless – If muscle relaxants are not contraindicated, use them. Any movement could result in a CSF leak, major blood loss, nerve root injury, post-op instability, and/or injury to retroperitoneal structures. Keep the patient normothermic – Should have the patient prewarmed and potentially heat the room. Preparation after induction can take quite a bit of time, so the patient can be hypothermic by the time the surgery is started. The surgeon may request a valsalva-like maneuver (sustained inspiration at 30–40 cm H2O).
There are many indications for this procedure: Lumbar radiculopathy (nerve/root compression), spondylolisthesis (one vertebrae slips over another), spondylolysis (structural defect in the pars interarticularis), lumbar disc disease (hernia or degeneration of lumbar discs), lumbar canal stenosis, lumbar spondylosis (breakdown of lumbar spine), lateral recess stenosis, metastatic tumor in the spine, lumbar spine tumor, neurogenic claudication The disc is removed piece-by-piece using curettes and disc-biting rongeurs. Risks include damage to the retroperitoneal structures such as the great vessels or intestines. There is also a risk of epidural bleeding, which can be significant.
In short, the structures of the spine have broken down or stenosed, requiring intervention. This procedure removes part of the lamina of a vertebral arch in order to relieve the pressure that is being put on the vertebral canal. In the event that the surgery is considered "minimally invasive", all of the major risks are reduced, but still present (blood loss, postoperative pain, etc).
