Extradural blood patch--why delay?

Seven patients are described in whom a prophylactic blood patch was instituted within 15 min of accidental dural puncture. Five of the patients received extradural anaesthesia before the blood patch, and one after the blood patch had been performed. In three of these patients further "top-up" doses of local anaesthetic were performed through the extradural catheter. The quality of analgesia obtained was satisfactory. No symptoms of spinal headache occurred in any of the patients.