Prevention of Hypotension During Spinal Anesthesia for Caesarean Section: Preload with Crystalloids or Hydroxyethyl Starch

Prevention of hypotension during spinal anesthesia for cesarean section avoids maternal and fetal side effects. The aim of this study is to compare the effects of prehydration with crystalloid and prehydration with Hydroxyethyl starch on maternal blood pressure and neonatal outcome during cesarean section under spinal anesthesia. We enrolled 72 full term women weighting between 50 and 85 Kg, classified as ASA I, scheduled for elective caesarean section under spinal anesthesia. Participants were randomly allocated equally to one of crystalloid or Hydroxyethyl starch (Voluven) groups. After arrival in the operating room and intravenous (IV) access, 500 ml of ringer solution was infused within 10-15 min before the initiation of the spinal block in the crystalloid group, but in the Voluven group, 500 ml of 6% Hydroxyethyl starch solution was infused to the patients. Hypotension occurred in 47.2% of patients in crystalloid group and 25% of patients in Voluven group and the statistical difference between two groups was meaningful.(P = 0.008). The incidence of nausea was %41.6 (15 patients) in crystalloid group vs %22.2 (8 patients) in Voluven group. Apgar scores in newborns in both groups were above 8. As conclusion, prophylactic prehydration with Hydroxyethyl starch was more effective than prehydration with crystalloid in the prevention of hypotension during spinal anesthesia for elective caesarean section.