title: The effect of neuraxial anesthesia on maternal cerebral hemodynamics.
abstract: OBJECTIVE
  Neuraxial anesthesia is known to reduce sympathetic tone and mean arterial pressure. Effects on cerebral hemodynamics in pregnancy are not well known. We hypothesize that cerebral hemodynamic parameters will change with respect to baseline following regional analgesia/anesthesia.
  
  
  METHODS
  We performed maternal transcranial Doppler of the middle cerebral artery in 20 women receiving epidural analgesia for labor, and 18 undergoing spinal anesthesia for cesarean section at baseline, 5 and 15 minutes. Systemic blood pressure (BP), systolic/diastolic/mean velocity, resistance and pulsatility index (PI) were recorded. Cerebral perfusion pressure, critical closing pressure (CrCP), resistance area product, and cerebral flow index were calculated.
  
  
  RESULTS
  Epidural placement was associated with significant decreases in systolic/diastolic BP/mean velocity/CrCP after 15 minutes, with a corresponding increase in PI. In the spinal group, systolic/diastolic BP/mean velocity uniformly decreased and remained low after 15 minutes, and PI significantly increased and remained constant after 15 minutes. No differences were seen in BP or cerebral hemodynamics between the groups.
  
  
  CONCLUSIONS
  This study demonstrates that both epidural analgesia and spinal anesthesia result in measurable cerebral hemodynamic changes in normotensive term pregnancy that are likely to be clinically insignificant as they do not affect perfusion pressure or flow.
authors: Department of Obstetrics and Gynecology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors: Ineke R
authors: IR
authors: Postma
authors: Department of Obstetrics and Gynecology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors: Teelkien R
authors: TR
authors: van Veen
authors: Department of Anesthesiology, St Mark's Hospital, Salt Lake City, Utah.
authors: Scott L
authors: SL
authors: Mears
authors: Division of Obstetrics and Prenatal Medicine, Department of Obstetrics and Gynecology, Erasmus Medical Center, Rotterdam, The Netherlands.
authors: Gerda G
authors: GG
authors: Zeeman
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital, Houston, Texas.
authors: Sina
authors: S
authors: Haeri
authors: Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital, Houston, Texas.
authors: Michael A
authors: MA
authors: Belfort
mesh_terms: D000328:Adult; D015360:Analgesia, Epidural; D016362:Analgesia, Obstetrical; D000701:Analgesics, Opioid / Q000494:pharmacology; D000773:Anesthesia, Obstetrical; D000775:Anesthesia, Spinal; D000779:Anesthetics, Local / Q000494:pharmacology; D001783:Blood Flow Velocity; D001794:Blood Pressure; D002045:Bupivacaine / Q000494:pharmacology; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D002585:Cesarean Section; D005260:Female; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000502:physiology; D009020:Morphine / Q000494:pharmacology; D011247:Pregnancy; D017585:Ultrasonography, Doppler, Transcranial; D014655:Vascular Resistance; D055815:Young Adult
chemical_list: D000701:Analgesics, Opioid; D000779:Anesthetics, Local; D009020:Morphine; D002045:Bupivacaine