| Risk Factors | Not Risk Factors |
|---|---|
| Lidocaine | Lidocaine dose |
| Addition of phenylephrine to 0.5% tetracaine | Addition of epinephrine to lidocaine |
| Lithotomy position | Presence of dextrose |
| Leg flexed (as for meniscectomy) | Paresthesia or blood-tinged CSF |
| Outpatient status | Hypotension |
CSF = cerebrospinal fluid.