title: Effect of sitting position on equal-dose spinal anaesthetic for caesarean section and post-partum tubal ligation.
abstract: BACKGROUND
  We studied the hypothesis that an equal spinal anaesthetic dose administered in the sitting position to patients undergoing post-partum tubal ligation (PPTL) and caesarean section (CS) would yield similar sensory block characteristics and analgesic efficacy.
  
  
  METHODS
  This prospective, non-randomised trial recruited 20 women undergoing PPTL within 48 h of vaginal delivery and 20 undergoing CS. Spinal anaesthesia comprising intrathecal hyperbaric bupivacaine 12 mg and morphine 100 μg was administered at L3/4 with patients sitting. Our primary end point was the maximal dermatomal sensory block (to cold).
  
  
  RESULTS
  Baseline demographics were comparable, but PPTL patients had greater parity, with mean ± standard deviation 17.54 ± 11.2 h from delivery to spinal anaesthesia, and shorter duration of surgery, 17.54 ± 11.2 vs. 40.3 ± 15.5 min. Similar maximal sensory blocks (to cold) were achieved in group PPTL vs. CS, T4 (T1-T5) vs. T3 (T1-T5), P = 0.104, in comparable times, 8.6 ± 2.6 vs. 7.6 ± 3.0 min, P = 0.267. PPTL patients had significantly faster two-segment block regression (70.7 ± 23.5 vs. 97.6 ± 23.9 min, P = 0.001) and to T10 (120.8 ± 35.6 vs. 145.1 ± 24.3 min, P = 0.016), with less hypotension (25% vs. 65%, P = 0.025) and phenylephrine (20.0 ± 60.6 μg vs. 120.0 ± 119.6 μg, P = 0.005).
  
  
  CONCLUSIONS
  The same dose of hyperbaric bupivacaine 12 mg and morphine 100 μg administered in the sitting position to both PPTL and CS parturients yielded similar maximal sensory blocks, but PPTL exhibited faster block regression and less hypotension/vasopressor requirement.
authors.affiliation: Department of Women's Anaesthesia, KK Women's and Children's Hospital, Singapore, Singapore.
authors.forename: S C
authors.initials: SC
authors.lastname: Kwok
authors.forename: W H L
authors.initials: WH
authors.lastname: Teoh
authors.forename: F
authors.initials: F
authors.lastname: Ithnin
mesh_terms: D000328:Adult; D000762:Anesthesia Recovery Period; D000773:Anesthesia, Obstetrical / Q000379:methods*; D000775:Anesthesia, Spinal / Q000379:methods*; D000779:Anesthetics, Local / Q000008:administration & dosage*; D002045:Bupivacaine / Q000008:administration & dosage*; D002585:Cesarean Section; D003080:Cold Temperature; D036861:Delivery, Obstetric; D005260:Female; D006801:Humans; D007022:Hypotension / Q000139:chemically induced; D007431:Intraoperative Complications / Q000139:chemically induced; D007813:Laparotomy; D009020:Morphine / Q000008:administration & dosage; D009294:Narcotics / Q000008:administration & dosage; D061646:Operative Time; D056888:Patient Positioning; D049590:Postpartum Period; D011247:Pregnancy; D011446:Prospective Studies; D013246:Sterilization, Tubal
chemical_list: D000779:Anesthetics, Local; D009294:Narcotics; D009020:Morphine; D002045:Bupivacaine