OBJECTIVE: To determine whether administration of parenteral analgesic affects clinical monitoring, diagnostic accuracy and outcome of patients with suspected acute appendicitis.

METHODS: Prospective, double-blind, placebo-controlled administration of tramadol and normal saline (NS). Patients 11 to 65 years old with abdominal pain for less than seven days, with possibility of acute appendicitis and needing clinical monitoring for detinitive diagnosis, were included. Changes in abdominal physical examination findings and pain response were evaluated 30 minutes after administration of tramadol and placebo which were given right after initial assessment. Accuracy in diagnosis, appendiceal perforation rate, and morbidity and mortality rates were the outcome measures.

RESULTS: One hundred sixty-three patients were enrolled. Eighty-four patients received tramadol (Grp 1) and 79 received NS (Grp 2). Seven patients, 5 in Grp 1 and 2 in Grp 2, did not undergo an operation because of nonsurgical diagnoses which were verified to be accurate during follow-up. One hundred fifty-six patients, 79 in Grp 1 and 77 in Grp 2, were admitted with a diagnosis of acute appendicitis and underwent surgery. There was no significant difference between the groups when comparing the accuracy of preoperative diagnosis and outcome of appendectomy in terms of perforation, morbidity, and mortality rates. In those receiving parenteral analgesics, there was significant pain relief

CONCLUSION: When compared with saline placebo, the administration of a parenteral analgesic (tramadol) to patients being monitored for possible acute appendicitis effectively relieved pain and did not alter the ability of the surgeons to accurately evaluate such patients.