[Anaphylactoid reaction to dibucaine during spinal anesthesia]

A 71-year-old man with a history of allergic rhinitis for 6 years received spinal anesthesia using 2 ml of 0.3% dibucaine for transurethral prostatectomy. Two months previously he had undergone prostate biopsy and cystoscopy under spinal anesthesia with isobaric bupivacaine uneventfully. Forty five minutes after injection of dibucaine he complained of itching in the periorbital area, and developed tremor and muscle rigidity followed by loss of consciousness. Soon after, his blood pressure decreased to 40 mmHg, and erythema appeared over his body. Symptoms were relieved by epinephrine, hydrocortisone and antihistamine agents, but ten minutes after the treatment he again developed hypotension and erythema. Continuous infusion of epinephrine was needed for complete relief of symptoms. An intradermal test with 0.3% dibucaine carried out 6 days after surgery demonstrated a 12 x 8 mm wheal with flare. Although anaphylactic reaction to an amide local anesthetic has been reported to be quite rare, this is the 7th case report of anaphylactic reaction to dibucaine used for spinal anesthesia in Japan.