Development and current status of combined spinal epidural anaesthesia

Combined spinal and epidural anaesthesia/analgesia is a method whereby drugs are applied intrathecally as a single dose and epidurally either continuously or intermittently via an epidural catheter. More than 50 years ago, first attempts were made to introduce this method into clinical practice but they found little general acceptance. Only during the last decades has tremendous progress been made in developing new, highly-sophisticated equipment: matching spinal and epidural needles and catheters, epidural needles with a separate conduit for the spinal needle or with an additional hole for the exit of the spinal needle as well as fixation devices for the spinal needle. A specific feature of the method is the only recently recognised epidural volume extension, which allows the use of low-dose drug combinations with sufficient analgetic properties but less cardiovascular compromise and fewer side-effects. This review describes the main and most important developmental steps and offers practical examples for its use in day-case surgery of the lower limb, in the "walking epidural" in obstetrics and in caesarean section. The method has become a valuable new tool in the armamentarium of the anaesthetist and part of daily routine in many clinics.