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

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 18-60 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.