title: Effect of intravenous vitamin C on postoperative pain in uvulopalatopharyngoplasty with tonsillectomy.
abstract: BACKGROUND
  Postoperative pain is a common problem in hospitals. Adults undergoing uvulopalatopharyngoplasty (UPPP) with tonsillectomy experience an unacceptable level of intense postoperative pain, especially during the first 24 h after surgery. This study investigated the analgesic effects of vitamin C in patients undergoing UPPP and tonsillectomy.
  
  
  METHODS
  This study was done on forty patients that were evaluated in a randomised double-blinded clinical trial. Patients included in the study were within the age range of 25-50 years with BMI<35, physical status I,II according to the American Society of Anesthesia (ASA) and who underwent uvulopalatopharyngoplasty and tonsillectomy. Patients with epilepsy, BMI>35, any neuropsychiatric disorders, a history of chronic pain, liver and/or renal disease, drug allergy, and drug abuse were excluded from the study. All patients underwent the same method of anaesthesia and surgical procedure. During the first 30 min after the beginning of the surgery, group C (vitamin C) received infusion of 3 g vitamin C in 500 mL of Ringer and group P received 6 mL normal saline in 500 mL of Ringer. Measurements of systolic blood pressure, diastolic blood pressure, mean arterial blood pressure and heart rate were recorded before and during anaesthesia and at intervals of 0,15,30 and 60 min after extubation. Pain severity was recorded according to VAS score at intervals of 0 (recovery room), 6, 12 and 24 h after the procedure, request for analgesic drugs (iv paracetamol or pethedine) according to total number of times of analgesic request and time of the first dose of analgesic use and dose of pethidine were also recorded by questionnaire.
  
  
  RESULTS
  There was a significant difference in evaluations for mean pain severity between the two groups at recovery room, 6, 12 and 24 h after surgery (P-value = 0.001). There was a significant difference in mean times that patient requested an analgesic, time of first dose of analgesic and pethidine dose between the two groups (P-value< 0.05). There was no significant differences in measurements of systolic blood pressure, diastolic blood pressure, mean arterial blood pressure and heart rate in different times between the two groups (P-value> 0.05). Blood loss was similar in the two groups (P-value> 0.05).
  
  
  CONCLUSIONS
  According to this study, administration of vitamin C 3 g IV intraoperative reduced postoperative pain without increased side-effects in patients undergoing UPPP and tonsillectomy.
authors.affiliation: Department of Anesthesiology, School of Medicine, Shahid Sadoughi University of Medical Sciences and Health Services, Yazd, Iran.
authors.forename: V
authors.initials: V
authors.lastname: Ayatollahi
authors.affiliation: School of Medicine, Shahid Sadoughi University of Medical Sciences and Health Services, Yazd, Iran.
authors.forename: S
authors.initials: S
authors.lastname: Dehghanpour Farashah
authors.affiliation: Department of Anesthesiology, School of Medicine, Shahid Sadoughi University of Medical Sciences and Health Services, Yazd, Iran.
authors.forename: S
authors.initials: S
authors.lastname: Behdad
authors.affiliation: Pain research center, Shahid Sadoughi University of Medical Sciences and Health Services, Yazd, Iran.
authors.forename: S
authors.initials: S
authors.lastname: Vaziribozorg
authors.affiliation: Department of Otorhinolaryngology - Head and Neck Surgery, Imam-Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: M
authors.initials: M
authors.lastname: Rabbani Anari
mesh_terms: D000082:Acetaminophen / Q000627:therapeutic use; D000328:Adult; D000700:Analgesics / Q000627:therapeutic use*; D000975:Antioxidants / Q000627:therapeutic use*; D001205:Ascorbic Acid / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008614:Meperidine / Q000627:therapeutic use; D008875:Middle Aged; D013517:Otorhinolaryngologic Surgical Procedures / Q000009:adverse effects*; D010147:Pain Measurement; D010149:Postoperative Pain / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control*; D014068:Tonsillectomy / Q000009:adverse effects*
chemical_list: D000700:Analgesics; D000975:Antioxidants; D000082:Acetaminophen; D008614:Meperidine; D001205:Ascorbic Acid