The clinical use of small-dose tetracaine spinal anesthesia for transurethral prostatectomy

In a double-blinded study, we compared conventional dose tetracaine (8 mg), small-dose tetracaine (4 mg) with added fentanyl and epinephrine, and smal l-dose tetracaine (4 mg) with added fentanyl subarachnoid anesthesia. Forty -five patients scheduled for transurethral resection of prostate (TURP) und er subarachnoid anesthesia were randomly assigned to Group 1 (8 mg hyperbar ic tetracaine), Group 2 (4 mg hyperbaric tetracaine, 10 mug fentanyl, and 0 .2 mg epinephrine), and Group 3 (4 mg hyperbaric tetracaine, 10 mug fentany l, and 0.2 mt saline). Evaluations were performed after spinal anesthesia. Subarachnoid block was successful in all patients except one in Group 1, wh o required general anesthesia by mask. The median peak sensory levels 10 mi n after the induction of spinal anesthesia in Group 1 was T8, which was sig nificantly higher than Group 2 and Group 3 (P < 0.05). The time of sensory and motor recovery in Group 3 was less than in Groups 1 and 2 (P < 0.05). H ypotension was observed in four patients in Group I and none in Groups 2 an d 3. We conclude that small-dose 4-mg hyperbaric tetracaine plus 10 mug fen tanyl might provide adequate anesthesia and fewer side effects for TURF whe n compared with the conventional (8 mg) dose.