Absolute
- Space occupying lesion with mass effect and evidence of increased ICP:
- Risk of cerebral herniation
- Suggested by midline shift or loss of cisterns on CT
- Posterior fossa mass
- Arnold-Chiari malformation
- Coagulopathy (see BSN Guidance):
- Platelets <40,000
- INR >1.4
- Anticoagulant & antiplatelet medication
- Skin infection at puncture site
- Patient refusal
Relative
- Brain, spinal and epidural abscess
- Issues with positioning:
- Respiratory distress
- Cardiovascular instability
- Poor mobility
- Spinal anomalies:
- Congenital anomalies
- Previous surgery
- Degenerative disease