evaluation the effect of intrathecally fentanyl added to lidocaine on interception of shivering in abdominal hysterectomy: randomized clinical trial

Background: shivering is a frequent phenomenon in postoperative period. post spinal shivering causes a major distress for patients and may induce some complications. investigations to control shivering could not mange it completely. objectives: the aim of this randomized single-blind study was to investigate how much the high dose (50 g) of intrathecally administered fentanyl would influence the incidence and severity of shivering in patients undergoing abdominal hysterectomy. methods: in this prospective clinical trial, seventy healthy patients scheduled for abdominal hysterectomy under spinal anesthesia using 75 mg of hyperbaric 5% lidocaine were randomly allocated to receive an additional 50 g (1 ml) of fentanyl intrathecally (group f) or normal saline 1 ml (groups).then the level of shivering was measured with crossly and mahajon scale and analyzed with chi-square test using spss version 17 software. results: the incidence of shivering up to two hours after spinal anesthesia was 13 from 35 patients (37.2 %) in group f, and 27 from 35 patients (77.2%) in group s. the difference was statistically significant (p < 0.01). the shivering score was significantly lower in group f. there was no difference in the incidence of pharmacologic side effects. conclusions: addition of 50 g fentanyl to 75mgof hyperbaric 5% lidocaine intrathecally can reduce the incidence and severity of shivering in patients who receive abdominal hysterectomy without increasing other side effects.