[Combined epidural-spinal analgesia during labor: a quantitative systematic review of the literature (meta-analysis)]. / Analgesia combinada epidural-intradural para el trabajo de parto: una revisión bibliográfica sistemática cuantitativa (metaanálisis).

OBJECTIVE: To perform a meta-analysis on the use of combined epidural-intrathecal analgesia during labor, including intrathecal fentanyl and/or morphine compared to usual epidural techniques. MATERIAL AND METHOD: A literature search was made looking for randomized clinical trials in MEDLINE, EMBASE and Cochrane Library. The size of the effect for quantitative variables was analyzed by weighted mean difference; for qualitative variables, by odds ratio. Variables analyzed were: labor duration, type of delivery (spontaneous, instrumental and caesarean section), motor blockade, pain, and satisfaction. The analysis used in most cases was a random effects model. RESULTS: A total of 21 trials, which included 3.646 patients, were selected out of the 38 initially found. The type of delivery variable with its 3 subgroups was the only one to show uniformity (p>Q 0.1; I(2)<50%). There were no differences in the variables analyzed except pain, which was advantageous for the group with intrathecal fentanyl or morphine by 0.55 points out of 10. CONCLUSION: Combined analgesia including intrathecal fentanyl-morphine does not offer significant advantages compared to the standard epidural.