fa مقایسه‌ی اثرات تجویز کلوئید قبل و بعد ازآنستزی اسپاینال Co-Loading)و (Pre-Loadingدر پیشگیری از هیپوتانسیون مادران دراعمال سزارین کارآزمایی بالینی Clinical Trials <p>Background and Objective: Hypotension associated with spinal anesthesia for cesarean section is still a clinical problem. The role of crystalloid preloading to prevent hypotension associated with spinal anesthesia in parturients during cesarean section has been challenged. However, studies with crystalloids predict that fluid loading should be more efficacious if administered immediately after induction of spinal anesthesia. The effects of colloid loading after spinal anesthesia in cesarean section have not been studied enough. The aim of this study was to compare pre and co-loading of hetastarch for the prevention of hypotension following spinal anesthesia for cesarean delivery. Materials and Methods: This randomized clinical trial study was performed in 112 parturients (ASA I or II) undergoing elective cesarean section. Patients were randomly allocated to one of the two groups to receive rapid infusion of 500 ml of 6% hydroxyethylstarch (HES) before spinal anesthesia (preloading group, n = 56), or rapid infusion of 500 ml of HES after induction of spinal anesthesia (co-loading group, n= 56). The incidence of hypotension and the amount of vasopressor, (ephedrine 5 mg/mL + phenylephrine 25 micg/mL) were compared in the treatment of hypotension. Results: There was no significant difference in hypotension between the two groups (P = 0.58). The pre-loading group used 2.2 &plusmn; 1 ml of vasopressor mixture compared with 1.7 &plusmn;0.7 ml in the co-loading group (P = 0.04) and the difference was significant. Conclusion: Colloid loading after induction of spinal anesthesia is as effective as preloading in reducing hypotension in cesarean section.</p> Keywords: Spinal anesthesia, Hypotension, Cesarean delivery, Colloid, Hetastarch, Vasopressors 1 9 http://journal.zums.ac.ir/browse.php?a_code=A-10-4-744&slc_lang=fa&sid=1 Mitra Golmohammadi میترا گل محمدی mitragolmohammadi@yahoo.com 5200319475328460059408 5200319475328460059408 Yes Dept. of Anesthesiology. School of Medicine, Urmia University of Medical Sciences, Urmia, Iran Peyman Mansuri پیمان منصوری 5200319475328460059409 5200319475328460059409 No Dept. of Anesthesiology. School of Medicine, Urmia University of Medical Sciences, Urmia, Iran Mina Jafari Javid مینا جعفری جاوید 5200319475328460059410 5200319475328460059410 No Dept. of Anesthesiology. School of Medicine, Urmia University of Medical Sciences, Urmia, Iran Hamidreza Khalkhali حمیدرضا خلخالی 5200319475328460059411 5200319475328460059411 No Dept. of Biostatistian& Epidemiolog. School of Medicine, Urmia University of Medical Sciences, Urmia, Iran Mir mousa Aghdashi میر موسی آقداشی 5200319475328460059412 5200319475328460059412 No Dept. of Anesthesiology. School of Medicine, Urmia University of Medical Sciences, Urmia, Iran