25 yo primip, 5'4", 190#, otherwise healthy. Never had surgery before. Failure to progress, some evidence of fetal intolerance, so we go to section. I sit her up, prep, drape, etc. 24 ga pencan via introducer, clear fluid at about L 4-5, deposit 1.6cc .75% marcaine with 25mcg fentanyl, free flow before and after injection. Lay her down, her feet and bottom are tingling, within 5 minutes she has a T 4 level to temp sensation, still can wiggle feet, but "they're numb". We get her prepped and draped, surgeon steps up, pinches the incision site -- "Ouch". No apparent anesthesia at the incision site, she felt nothing when the catheter went in, legs were flaccid. Wait 5 minutes, test again -- "OUCH". She describes exactly what the surgeon is doing and where. Still has a T-4 sensory level to temp change, but not to sharp stim.

So, what are reasons a spinal fails? What would you do next?