Does the evidence support the use of spinal and epidural anesthesia for surgery?

When spinal and epidural anesthesia were introduced into clinical practice, their primary use was as an alternative to general anesthesia. Later, largely as a result of the realization that opioids could be safely and effectively used to produce selective spinal analgesia, spinal and epidural (neuraxial) analgesia began to be used specifically for the treatment of perioperative pain. We present a systematic review of the literature on neuraxial anesthesia and analgesia, new meta-analyses that illustrate the powerful effect of improvements in perioperative safety in general on the ability of neuraxial techniques to make a difference, and a consideration of why a literature analysis does not provide clear answers.