high dose but not low dose granisetron decreases incidence and severity of post anesthesia shivering (pas) and postoperative nausea and vomiting (ponv) following lower abdominal surgeries under spinal anesthesia

Background: post anesthesia shivering (pas) is one of the common complications throughout recovery from general and regional anesthesia. the incidence of this complication is reported to be 40-70% among patients. pas occurrence depends on various factors such as age, gender and drugs used in anesthesia and surgery time. granisetron is a serotonin 5ht3 receptor antagonist. beneficial effects of such drugs have been shown in a limited number of studies. in this study, preventive effects of granisetron in prevention of shivering, nausea and vomiting following spinal anesthesia were evaluated in patients undergoing lower abdominal surgery. methods: one hundred and five patients aged 1860 years and with asa class i or ii who were scheduled to undergo elective lower abdominal surgery under spinal anesthesia were studied in 3 groups of 35 patients. after spinal anesthesia, group l received low dose granisetron with a dose of 10μg/kg, group h received high dose granisetron with a dose of 40 μg/kg and group c received normal saline as placebo. after leaving the operating room, patients were monitored in terms of shivering occurrence, time and severity of it and incidence of nausea and vomiting. results: incidence of shivering, nausea and vomiting was significantly lower in group h than c. (p=0.009 and 0.008, respectively). however, there was no significant difference between l and c or l and h groups in terms of shivering, or nausea and vomiting occurrence. no side effects of granisetron were observed in the study. conclusion: high dose granisetron with dose of 40μg/kg significantly reduced the prevalence and severity of pas and ponv in comparison to placebo.