title: Effectiveness of nitrous oxide for postpartum perineal repair: a randomised controlled trial.
abstract: OBJECTIVE
  To compare the effectiveness of self-administered 50% nitrous oxide and conventional infiltrative anaesthesia with 1% prilocaine hydrochloride in postpartum perineal repair.
  
  
  METHODS
  A total of 100 women were prospectively enrolled and randomised to receive either infiltrative anaesthesia or a self-administered nitrous oxide mixture (Livopan(©)) for pain relief during postpartum perineal suturing. Besides data concerning anaesthesia, characteristics of patients and labour were documented for statistical analysis. Pain experienced during perineal repair was assessed using the short form of the McGill Pain Questionnaire (SF-MPQ).
  
  
  RESULTS
  Forty-eight women received nitrous oxide and 52 underwent perineal suturing after infiltrative anaesthesia. There were no statistically significant differences regarding maternal age, body mass index (BMI), duration of pregnancy and suturing time between the groups. The most frequent birth injury was second-degree perineal laceration in the study group [22/48; 46%] and episiotomy in the control group [18/52; 35%]. Pain experienced during genital tract suturing and patients' satisfaction showed no statistically significant differences between the groups. Thirty-seven women in the study group and 47 in the control group were satisfied with the anaesthesia during perineal repair and would recommend it to other parturients [37/48, 77% vs. 47/52, 90%; p=0.0699).
  
  
  CONCLUSIONS
  Nitrous oxide self-administration during genital tract suturing after vaginal childbirth is a satisfactory and effective alternative to infiltrative anaesthesia.
authors.affiliation: Department of Obstetrics and Gynaecology, University Medical Centre Mannheim, Heidelberg University, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Berlit
authors.forename: Benjamin
authors.initials: B
authors.lastname: Tuschy
authors.forename: Joachim
authors.initials: J
authors.lastname: Brade
authors.forename: Jade
authors.initials: J
authors.lastname: Mayer
authors.forename: Sven
authors.initials: S
authors.lastname: Kehl
authors.forename: Marc
authors.initials: M
authors.lastname: Sütterlin
mesh_terms: D000328:Adult; D018712:Analgesics, Non-Narcotic / Q000008:administration & dosage*; D000779:Anesthetics, Local / Q000008:administration & dosage; D005260:Female; D006801:Humans; D009609:Nitrous Oxide / Q000008:administration & dosage*; D010502:Perineum / Q000601:surgery*; D049590:Postpartum Period; D011247:Pregnancy; D011318:Prilocaine / Q000008:administration & dosage; D011446:Prospective Studies; D012646:Self Administration; D055815:Young Adult
chemical_list: D018712:Analgesics, Non-Narcotic; D000779:Anesthetics, Local; D011318:Prilocaine; D009609:Nitrous Oxide
keywords: Birth injury; Nitrous oxide; Perineal repair; Vaginal delivery