Comparison of Analgesic Methods, and Their Effects on Patient Recovery, Following Liver Surgery

Overview

The provision of adequate pain relief following major liver surgery is essential, not only for patient comfort, but for the prevention of complications, such as chest infection. Commonly, pain relief in the first few days after surgery is provided by epidural analgesia. Drugs are delivered to the area around the spinal cord, through a fine plastic tube placed in the patients back, and this blocks sensation from the abdomen downwards, thereby providing effective pain relief without the need for opiate analgesia (e.g. morphine). Opiate analgesia can cause nausea, drowsiness and constipation, and its use should be minimised. Epidurals, however, can be associated with some problematic side effects. Low blood pressure is commonly encountered, and not only can its treatment be associated with complications, but patients are often confined to bed. Mobility can also be limited if muscle function in the legs, (in addition to sensation), is inadvertently affected by the epidural drugs. Other problems associated with epidural use are the relatively common failure of the technique to provide adequate analgesia (20%), and some extremely rare but potentially disastrous complications of epidural insertion. An alternative technique, is the provision of pain relief directly into the wound, via one or more multi-holed tubes(catheters), placed either in or close to the wound. This technique alone does not provide as effective analgesia as a functioning epidural, but when combined with other intravenous or oral analgesia, has been shown to be effective following a variety of surgical procedures. It is hypothesised that, following major liver surgery, the use of this latter technique may result in superior outcome and faster recovery, when compared with epidural, by avoidance of the side effects and complications discussed above. In this study, patients scheduled to undergo major liver surgery at the Royal Infirmary of Edinburgh with be randomly assigned to receive the first two days of pain relief either by epidural, or by wound catheter plus additional analgesia. Both groups will then receive an identical oral analgesic regime for the remainder of the hospital stay. Outcomes of interest will include the quality of pain relief attained, patient mobility, frequency of complications, and overall recovery time.