Clinical evaluation of a spinal catheter technique in femoro-popliteal graft surgery.

The use of a 24-gauge catheter for continuous spinal anaesthesia was evaluated in 20 patients undergoing femoro-popliteal graft surgery for occlusive disease. The catheter was inserted through either a Tuohy or Quincke-tip needle and isobaric amethocaine used for the initial injection. In five patients identification of the subarachnoid space was not straightforward, but clear difficulty with catheter insertion was encountered in only one. The range of blocks seen was wider than expected, but it was adequate for surgery 15 minutes after injection in 16 of the 20 patients. In another three the injection of a small dose of hyperbaric bupivacaine produced the necessary extension of block. Two patients (10%) required a general anaesthetic, one because of grossly inadequate spread of solution, the other because the catheter kinked and prevented injection of a second dose after the start of surgery.