title: [Stereological study of the placenta in parturients with different prophylactic measures for hypotension during spinal anesthesia for cesarean section].
abstract: OBJECTIVE
  To explore the optimal approach to the prevention of hypotension during cesarean section for the benefits of both the parturients and the newborns.
  
  
  METHODS
  Forty singleton full-term pregnant women undergoing elective cesarean delivery were randomly allocated into two equal groups. For prevention of hypotension during spinal anesthesia, ephedrine or pre-anesthetic volume with Voluven was administered. The changes of blood pressure, heart rate, and Apgar scores of the newborns were monitored and recorded, and the umbilical arterial blood gas variables were compared between the two groups. The placental samples were collected and immunohistochemistry for CD34 was performed for stereological study of the placental villous capillaries.
  
  
  RESULTS
  The umbilical arterial PaCO(2), PaO(2) and Apgar scores showed no significant differences between the two groups (P<0.05). The heart rate, incidence of hypotension and the lactic acid value were significantly higher, and the umbilical arterial pH significantly lower in ephedrine group than in the Voluven group (P>0.05). While the length density of the villous capillaries was comparable between the two groups (P>0.05), the volume density of the villous capillaries was significantly decreased in ephedrine group (P<0.05).
  
  
  CONCLUSIONS
  Pre-anesthetic volume expansion with Voluven can maintain stable hemodynamics during spinal anesthesia and also efficiently improve the tissue perfusion, microcirculation and uteroplacental blood flow, thus increasing the oxygen supply to the fetus.
authors.affiliation: Department of Anesthesiology, First Affiliated Hospital of Jinan University, Guangzhou 510630, China. sbg14608@163.com
authors.forename: Bing
authors.initials: B
authors.lastname: Shuai
authors.forename: Xue-mei
authors.initials: XM
authors.lastname: Peng
authors.forename: Rui-man
authors.initials: RM
authors.lastname: Li
authors.forename: Ya-lan
authors.initials: YL
authors.lastname: Li
authors.forename: Dong-hua
authors.initials: DH
authors.lastname: Hu
mesh_terms: D000328:Adult; D000773:Anesthesia, Obstetrical / Q000009:adverse effects; D000775:Anesthesia, Spinal / Q000009:adverse effects*; D002585:Cesarean Section; D017558:Elective Surgical Procedures; D005260:Female; D006801:Humans; D006895:Hydroxyethyl Starch Derivatives / Q000008:administration & dosage*; D007022:Hypotension / Q000209:etiology / Q000517:prevention & control*; D010920:Placenta / Q000033:anatomy & histology / Q000098:blood supply*; D021041:Placental Circulation / Q000187:drug effects; D010952:Plasma Substitutes / Q000008:administration & dosage; D011247:Pregnancy
chemical_list: C485123:HES 130-0.4; D006895:Hydroxyethyl Starch Derivatives; D010952:Plasma Substitutes