The effect of ephedrine on maternal hypotermia

Purpose: The purpose of the study was to investigate the effect of bolus and small doses of ephedrine on maternal hypotermia which we use for treating maternal hypotension under spinal anesthesia.Methods: 110 ASA I-II patients who developed maternal hypotension were included into the study. After getting the operating room the patients who did not get premedication were monitorized and core (tympanic membrane) and peripheral body aksillar temperatures were measured. All the cases was prehydrated with 10 mL/kg ringer lactate after intravenous canulation. Spinal anesthesia was performed at sitting pozition at L3-L4 or L4-L5 space by using Quincke 25G spinal needle with 12 mg. bupivacaine + 15 ?g fentanyl. The patients who developed hypotension were seperated into two groups by envelope technique.Grup I: Ephedrine bolus 5 mg+ ephedrine infusionGrup B: Ephedrine bolus 5 mg+SF infusionIt was allowed to systolic pressure to change ± % 20 from basal values. Ephedrine solutions were prepared at 3mg/mL. Ephedrine solution infusion started at 10mL/hour after hypotension occured.(0,5 mg/minute). These infusions were folded or reduced twice to continue basal systolic pressures. The body temperature under < 35.5 ºC was accepted as hypothermia. Shivering was evaluated with a 4 points shivering scale. The cases who had serious shivering after labour were treated with 20 mg. IV meperidin. Heat comfort score was evaluated with a 10 points scale.The newborn?s rectal temperature was measured, APGAR Scores (1, and.5. mins.) recorded. Umblical vein-arterial blood gase and acid-base status were recorded. After operation, all the patients were observed in post-op unit minimally for 30 minutes until the spinal block level returned to L5 or having stabil vital signs. Then they were discharged to obstetrics service.Results: In Gruop I, body core temperatures which measured at 10 th,20 th,35 th,40 th,45 th and 50 th minutes were significiantly higher than Group B.(p<0.05). Axillary temperatures were similar between groups. There were no differences for the heat comfort and shivering scores between groups. The maternal hypothermia incidence in Group I was % 65.5( 36/55) and significantly lower than the Group B which maternal hypothermia incidence was %85.5 (47/55) (p<0.05). In Group I newborn rectal temperatures and total used dose of ephedrine was significiantly higher than Grup B (p<0.05).In Group I 35 th, 40 th, 45 th and 50 th minutes systolic and mean arterial pressures were higher than Group B. (p< 0.05).There were no differences between groups for adverse effects such as nausea, vomiting, pain and itching.Conclusion: As a result, we found that using ephedrine infusion for treating maternal hypotension that occured at women who goes cesarean section under spinal anesthesia, prevent maternal and neonatal hypothermia. We think that these two effects of this drug may be beneficial for clinical practice.Key words: Maternal hypothermia, Maternal hypotension, Spinal anesthesia, Ephedrine