[Spinal anesthesia with isobaric bupivacaine for percutaneous nephro-ureterolithotomy]

The duration of analgesia and the cardiovascular changes during anesthesia of spinal blockade with isobaric bupivacaine were examined in 36 patients between 21 and 75 years old undergoing percutaneous nephro-ureterolithotomy. Injection of 0.25% or 0.5% bupivacaine 3.0-4.0 ml through the L3-4 or L2-3 intervertebral space in the horizontal posture resulted in spread of hypalgesia to T6 in 30 patients and of analgesia to T6 in about a half of the patients. In six patients, another intrathecal injection of 2 ml of bupivacaine was performed because their analgesia level had been under T8. Although the operation took 32-141 min. (mean 77.7 +/- 27.5 min.), there was no case requiring exigent exchanging anesthesia for general anesthesia. The frequencies of the hypotension, bradycardia and nausea in spinal blockade with isobaric bupivacaine were not so different from those of the previous epidural anesthesia in 29 patients undergoing the same operation. Most of the cardiovascular changes in the spinal blockade with isobaric bupivacaine happened within 20-30 min. after intrathecal injection of bupivacaine. Spinal anesthesia with isobaric bupivacaine proved satisfactory for percutaneous nephro-ureterolithotomy.