Spinal anaesthesia with meperidine as the sole agent.

Twenty male patients of ASA physical status I or II undergoing surgery of the perineal or inguinal areas received intrathecal meperidine in a dose of 1 mg X kg-1 as the sole anaesthetic agent. There was sensory and motor block within ten minutes of intrathecal injection of meperidine and surgery was performed with complete analgesia. The duration of surgery was 39.7 +/- 14 (mean +/- SD) minutes. Prolonged postoperative analgesia was obtained and some patients did not require additional narcotic analgesic during the postoperative period, lasting up to seven days. Side effects included nausea and vomiting (six patients), hypotension (five patients), pruritus (five patients) and urinary retention (two patients). There was no early or late respiratory depression. It is concluded that intrathecal meperidine in a dose of 1 mg X kg-1 is effective as the sole agent for spinal anaesthesia and produces prolonged postoperative analgesia. It offers an advantage for such painful operations as haemorrhoidectomy and anal fissurectomy where its prolonged analgesic effect is desirable. It could also serve as an alternative agent for spinal anaesthesia when a local anaesthetic is not available.