title: Predicting prolonged fetal heart rate deceleration following intrathecal fentanyl/bupivacaine.
abstract: BACKGROUND
  Intrathecal opioids for labor analgesia are occasionally associated with fetal heart rate abnormalities. We wanted to identify risk factors for this occurrence.
  
  
  METHODS
  The fetal tracings of 151 consecutive patients were reviewed for the period including 30 min before and 60 min after combined spinal-epidural analgesia using intrathecal bupivacaine with fentanyl. Their progress of labor at injection was also recorded.
  
  
  RESULTS
  Lack of fetal head engagement (odds ratio 5.5, 95% CI 2.1-14.2) and the presence of variable fetal heart rate decelerations (odds ratio 3.6, 95% CI 1.6-8.4) were associated with prolonged fetal heart rate deceleration after combined spinal-epidural analgesia.
  
  
  CONCLUSIONS
  This case-control study suggests that if the fetal head is not engaged or if the fetus is experiencing variable decelerations, there is an increased risk of prolonged fetal heart rate deceleration following intrathecal fentanyl/bupivacaine. This finding must now be confirmed in a cohort study.
authors.affiliation: Department of Anesthesia, Hospital of the University of Pennsylvania, Philadelphia, PA 19104, USA. gaiserr@uphs.upenn.edu
authors.forename: R R
authors.initials: RR
authors.lastname: Gaiser
authors.forename: M
authors.initials: M
authors.lastname: McHugh
authors.forename: T G
authors.initials: TG
authors.lastname: Cheek
authors.forename: B B
authors.initials: BB
authors.lastname: Gutsche
mesh_terms: D000328:Adult; D000701:Analgesics, Opioid / Q000009:adverse effects*; D000773:Anesthesia, Obstetrical / Q000009:adverse effects*; D000779:Anesthetics, Local / Q000009:adverse effects*; D002045:Bupivacaine / Q000009:adverse effects*; D016022:Case-Control Studies; D015331:Cohort Studies; D003864:Depression, Chemical; D005260:Female; D005283:Fentanyl / Q000009:adverse effects*; D006340:Heart Rate, Fetal / Q000187:drug effects*; D006801:Humans; D007231:Infant, Newborn; D007278:Injections, Spinal; D007743:Labor, Obstetric; D016017:Odds Ratio; D011247:Pregnancy; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D000701:Analgesics, Opioid; D000779:Anesthetics, Local; D005283:Fentanyl; D002045:Bupivacaine