PREEMPTIVE ANALGESIA WITH AMITRIPTYLINE IN WOMEN UNDERGOING ABDOMINAL HYSTERECTOMY: A RANDOMIZED CLINICAL TRIAL

Abstract

The concept of preemptive analgesia, albeit long-standing, has reemerged. Consequently, recent research has focused on testing a variety of drugs preoperatively to prevent the occurrence of postoperative pain, a major factor of morbidity. Amitriptyline is a tricyclic antidepressant used to treat chronic pain. Because amitriptyline acts on pain transmission pathways, it could theoretically be used as an agent for the prevention of postoperative pain. This study evaluated the effectiveness of amitriptyline in preventing pain in patients submitted to hysterectomy, the most commonly performed gynecological surgery. A randomized, double-blind clinical trial was conducted with 145 patients, 72 of these receiving amitriptyline and 73 placebo. All patients were evaluated at 6, 12, 24 and 48 hours after surgery using a visual analog scale (VAS) for pain and algometry to determine the pressure-pain threshold. Statistical analysis was conducted using the chi-square test of association, Student's t-test, and the Mann-Whitney test, with Fisher's exact test being used whenever appropriate. No statistically signicant difference was found between the two groups with respect to pain at any of the time points evaluated, leading to the conclusion that at a dose of 25 mg, amitriptyline is ineffective in preventing postoperative pain in patients submitted to abdominal hysterectomy