title: Reduction of bupivacaine dose in spinal anaesthesia for caesarean section may improve maternal satisfaction by reducing incidence of low blood pressure episodes.
abstract: BACKGROUND
  Spinal anaesthesia for caesarean section exposes to high incidence of arterial hypotension which can result in maternal and neonatal morbidity. We hypothesized that the reduction of this dose from 10 mg to 7.5 mg would minimize hypotension without altering pain relief.
  
  
  METHODS
  In this double-blind prospective study, 80 ASA1 women scheduled for elective caesarean section were randomized into two groups A and B receiving respectively 10 and 7.5 mg of isobaric bupivacaine both with 25 microg of fentanyl and 100 microg of morphine in spinal anaesthesia. Intravenous ephedrine was administered for each episode of hypotension. We recorded sensory and motor block, intraoperative pain, nausea and vomiting. In postanaesthesia care unit, sensory and motor recoveries were measured and maternal satisfaction rate was assessed.
  
  
  RESULTS
  In group A, a larger dose of ephedrine was needed (32 +/- 23 vs 19 +/- 16 mg; p = 0.004). Incidence of sensory block above T4 (52 vs 10%; p < 0.001), nausea (52 vs 22%; p = 0.005) and vomiting (25 vs 8%; p = 0.03) were all higher than in group B. Arterial hypotension was less frequent in group B (68 vs 88%; p = 0.03). The time required for recovery to T10 sensory level and motor regression were shorter than in group A (p < 0.001) and the satisfaction rate was higher than in group A (excellent and good in 90% vs 67%; p = 0.03). There was no difference in pain relief.
  
  
  CONCLUSIONS
  A dose of 7.5 mg of isobaric bupivacaine reduced incidence of hypotension, nausea and vomiting and improved patient satisfaction.
authors.affiliation: Department of Anaesthesiology, ICU and Emergency Medicine, Mongi Slim Hospital, La Marsa, Tunisia. msmebazaa@gmail.com
authors.forename: Mhamed S
authors.initials: MS
authors.lastname: Mebazaa
authors.forename: Sonia
authors.initials: S
authors.lastname: Ouerghi
authors.forename: Riadh
authors.initials: R
authors.lastname: Ben Meftah
authors.forename: Maamoun
authors.initials: M
authors.lastname: Ben Cheikh
authors.forename: Tahar
authors.initials: T
authors.lastname: Mestiri
authors.forename: Mohamed S
authors.initials: MS
authors.lastname: Ben Ammar
mesh_terms: D000328:Adult; D000773:Anesthesia, Obstetrical / Q000009:adverse effects*; D000775:Anesthesia, Spinal / Q000009:adverse effects*; D000779:Anesthetics, Local / Q000008:administration & dosage*; D002045:Bupivacaine / Q000008:administration & dosage*; D002585:Cesarean Section; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007022:Hypotension / Q000453:epidemiology / Q000517:prevention & control*; D015994:Incidence; D017060:Patient Satisfaction; D011247:Pregnancy
chemical_list: D000779:Anesthetics, Local; D002045:Bupivacaine