Continuous spinal anesthesia: dose requirements and characteristics of the block.

BACKGROUND AND OBJECTIVES

A fine-bore 28G CoSpan spinal catheter was used to provide continuous spinal anesthesia for major upper and lower abdominal, peripheral vascular, and orthopedic surgery in 90 patients, aged 31-91 years.

METHODS

Initial doses (0.5-2.0 mL) of hyperbaric bupivacaine 0.5% were given and followed, if needed, by additional doses of 0.5-1.0 mL to achieve a satisfactory blockade for the proposed type of surgery. The incidence of hypotension, ambulatory postdural puncture headache, and technical problems encountered with insertion of the spinal catheters were recorded.

RESULTS

The technique of continuous spinal anesthesia was successful and easy to learn. Satisfactory sensory and motor blockade was achieved within 12-18 minutes, and surprisingly small amounts were needed in those patients undergoing limb surgery.

CONCLUSIONS

Mild postdural puncture headache occurred in four patients, but none of the patients required blood patch. One catheter broke during removal; since then, it has been our policy to remove a catheter with the patient in a flexed position.