Prophylaxis Ephedrine or Ondansetron Prevents Hypotension After Spinal Anesthesia for Cesarean Section

Prophylaxis Ephedrine or Ondansetron Prevents Hypotension After Spinal Anesthesia for Cesarean Section

Prophylaxis Ephedrine or Ondansetron Prevents Hypotension After Spinal Anesthesia for Cesarean Section; a Randomized, Double Blinded, Placebo Controlled Trial

Maternal hypotension after spinal anesthesia in parturients undergoing cesarean section is a very common problem leading to several complications to both patients and their babies. It can cause maternal discomfort, lightheadedness, nausea and vomiting. The most important complication is the decreasing blood flow to babies; which may lead to fetal acidosis. Many interventions has been studied in order to prevent hypotension after spinal anesthesia in cesarean section e.g., fluid loading: colloid vs crystalloid, medications: ephedrine, phenylephrine, and metaraminol, etc. The recent study showed ondansetron (the antiemetic drug) can be effectively used to prevent hypotension after spinal anesthesia in normal patients or parturients. The action of ondansetron is believed to inhibit Bezold-Jarish reflex. This aim of this study is to compare the efficacy of ephedrine and ondansetron in the prevention of maternal hypotension after spinal anesthesia in cesarean section.

Ondansetron or ephedrine will be given immediately after spinal anesthesia, then record blood pressure and heart rate one-minutely until delivery.

Inclusion Criteria: Age > 18 years Elective cesarean section Patient accept spinal anesthesia ASA classification I-II Term, Singleton pregnancy Understand all process in this study Exclusion Criteria: DM any type that not the gestational DM Hypertensive disorder BMI>40 Complicated pregnancy such as placenta previa, preeclampsia Allergic to study drugs Long QT syndrome Contraindication to spinal anesthesia

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