The Effect of Remifentanil or Fentanyl on Postoprative Nausea and Vomiting after Cesarean Section

INTERVENTION: Fentanyl 2 microg/kg pulse morphin 0.1mg/kg intravenously, Duration of treatment: time from after clamping of umbilical cord to completion of surgery Fentanyl injection (2 microg/kg/h) intravenously, Duration of treatment: time from after clamping of umbilical cord to completion of surgery Intervention 1: Remifentanil injection (0.05 microg /kg/h) intravenously, Duration of treatment: time from after clamping of umbilical cord to completion of surgery. Intervention 2: Fentanyl 2 microg/kg pulse morphin 0.1mg/kg intravenously, Duration of treatment: time from after clamping of umbilical cord to completion of surgery. Intervention 3: Fentanyl injection (2 microg/kg/h) intravenously, Duration of treatment: time from after clamping of umbilical cord to completion of surgery. Remifentanil injection (0.05 microg /kg/h) intravenously, Duration of treatment: time from after clamping of umbilical cord to completion of surgery Treatment ‐ Drugs CONDITION: Complications of anaesthesia during pregnancy. ; Other complications of anaesthesia during pregnancy Other complications of anaesthesia during pregnancy PRIMARY OUTCOME: Frequency of PONV. Timepoint: at recovery, 4, 8, 12 and 24 hours after surgery. Method of measurement: counting. Nausea intensity. Timepoint: at recovery, 4, 8, 12 and 24 hours after surgery. Method of measurement: Visual Analogous Scale (VAS) and scoring from 0 to 10. SECONDARY OUTCOME: Metoclopramide consumption. Timepoint: at recovery, 4, 8, 12 and 24 hours after surgery. Method of measurement: in miligram of drug. Opioid consumption. Timepoint: at recovery, 4, 8, 12 and 24 hours after surgery. Method of measurement: in miligram of opioid. Pain intensity. Timepoint: at recovery, 4, 8, 12 and 24 hours after surgery. Method of measurement: Visual Analogous Scale (VAS) and scoring from 0 to 10. INCLUSION CRITERIA: INCLUSION CRITERIA: Parturients, ASA physical status I‐II, scheduled for elective cesarean section, under general anesthesia Exclusion Criteria: Allergy to fentanyl or remifentanil, atopia, diabetes mellitus, presence of liver or kidney diseases, drugs abuse, presence of complicated pregnancy such as hypertension or preeclampsia