Comparative Study between Continuous Spinal Anesthesia and Combined Spinal Epidural Anesthesia in Knee Surgeries

Abstract

C ontinuous spinal anesthesia (CSA) is the technique of producing and maintaining spinal anesthesia with small doses of local anesthetic which are injected intermittently into the subarachnoid space via an indwelling catheter. It is considered a longstanding anesthetic technique that could be used for surgery of the lower limbs and lower abdomen. It is an underutilized technique in modern anesthesia practice. Compared with other techniques of neuraxial anesthesia as single-dose spinal anesthesia and continuous epidural anesthesia, it has shown several advantages such as administration of local anesthetics in small incremental doses titrated to the individual patient’s needs, reduced requirements of local anesthetics and thus decreased systemic toxic effects, ensured cardiovascular stability, and extended anesthesia by supplemental application of spinal local analgesics when surgery is unexpectedly extended. The combined spinal–epidural technique (CSE) can be defined as the intentional injection of drug into the subarachnoid space and the placement of a catheter into the epidural space as part of the same procedure. This technique combines the rapidity, density, and reliability of the subarachnoid block with the flexibility of continuous epidural block to extend duration of analgesia.