title: Intrathecal opioids versus epidural local anesthetics for labor analgesia: a meta-analysis.
abstract: OBJECTIVE
  Some anesthesiologists contend that intrathecal opioid administration has advantages over conventional epidural techniques during labor. Randomized clinical trials comparing analgesia and obstetric outcome using single-injection intrathecal opioids versus epidural local anesthetics suggest that intrathecal opioids provide comparable analgesia with few serious side effects. This meta-analysis compared the analgesic efficacy, side effects, and obstetric outcome of single-injection intrathecal opioid techniques versus epidural local anesthetics in laboring women.
  
  
  METHODS
  Relevant clinical studies were identified using electronic and manual searches of the literature covering the period from 1989 to 2000. Searches used the following descriptors: intrathecal analgesia, spinal opioids, epidural analgesia, epidural local anesthetics, and analgesia for labor. Data were extracted from 7 randomized clinical trials comparing analgesic measures, incidence of motor block, pruritus, nausea, hypotension, mode of delivery, and/or Apgar scores.
  
  
  RESULTS
  Combined test results indicated comparable analgesic efficacy 15 to 20 minutes after injection with single-injection intrathecal opioid administration. Intrathecal opioid injections were associated with a greater incidence of pruritus (odds ratio, 14.01; 99% confidence interval, 6.9 to 28.3), but there was no difference in the incidence of nausea or in the method of delivery.
  
  
  CONCLUSIONS
  Published studies suggest that intrathecal opioids provide comparable early labor analgesia when compared with epidural local anesthetics. Intrathecal opioid administration results in a greater incidence of pruritus. The choice of technique does not appear to affect the method of delivery.
authors.affiliation: Department of Anesthesiology, University of Nebraska Medical Center, Omaha, Nebraska 98198-4455, USA. BBUCKLIN@UNMC.EDU
authors.forename: Brenda A
authors.initials: BA
authors.lastname: Bucklin
authors.forename: David H
authors.initials: DH
authors.lastname: Chestnut
authors.forename: Joy L
authors.initials: JL
authors.lastname: Hawkins
mesh_terms: D015360:Analgesia, Epidural / Q000009:adverse effects; D016362:Analgesia, Obstetrical / Q000009:adverse effects; D000701:Analgesics, Opioid / Q000008:administration & dosage* / Q000009:adverse effects; D000779:Anesthetics, Local / Q000008:administration & dosage* / Q000009:adverse effects; D036861:Delivery, Obstetric; D005260:Female; D006801:Humans; D007268:Injections, Epidural; D007278:Injections, Spinal; D009325:Nausea / Q000139:chemically induced; D010147:Pain Measurement; D011247:Pregnancy; D011537:Pruritus / Q000139:chemically induced
chemical_list: D000701:Analgesics, Opioid; D000779:Anesthetics, Local