[The spread of spinal anesthesia in young patients].

We have studied the spread of spinal anesthesia with Neo-percamine S, containing hyperbaric dibucaine, in 20 younger patients (13-18 yr) and 20 older patients (22-61 yr). In younger patients, 2.17 +/- 1.7 (mean +/- SD) ml of the anesthetic solution blocked 19.4 +/- 1.7 spinal segments. In older patients, 2.22 +/- 0.18 ml of the solution blocked 16.3 +/- 0.18 spinal segments. Spinal anesthesia higher than T3 level was observed in 45% of the younger patients, whereas such level of spinal anesthesia was not observed in the older patients. Our results suggest that hyperbaric dibucaine solution for spinal anesthesia may have a tendency to produce an unexpectedly extensive spread of anesthesia in young patients.