Spinal anesthesia with pentazocine for total abdominal hysterectomy.

Intraspinal pentazocine, 1.5 mg/kg, produced sufficient analgesia and moter block in 50 cases of abdominal total hysterectomy. Pentazocine, a derivative of benzomorphans, shares some common characteristics with local anesthetics in the chemical structure. Both agents have an aromatic ring and an intermediate chain, in common, which connects the former to nitrogen moiety, and the local anesthetic action was anticipated. The onset of the sensory block was 3.2 +/- 0.9 (mean +/- SD) min, and the maximum level was T10 and T4 with mean level of T6. The onset of motor weakness at the knee was 4.1 +/- 1.9 min, and the duration was 108 +/- 10.5 min.