Pre-emptive analgesia for chronic limb pain after amputation for peripheral vascular disease: a systematic review.

BACKGROUND: Chronic stump and phantom limb pain after amputation for critical ischemia significantly affect patients' quality of life and pose challenging clinical problems. Pre-emptive analgesia attempts to prevent chronic postoperative pain by minimizing painful stimuli before and during surgery.
METHODS: This systematic literature review aimed to evaluate the evidence supporting the use of pre-emptive analgesia in minimizing the risk of chronic stump and phantom pain after lower limb amputation for critical ischemia of peripheral vascular disease.
RESULTS: A total of 11 studies have been retrieved. Five different types of analgesic drugs were evaluated (local anesthetics, opiates, N-methyl-D-aspartate receptor antagonists, a(2)-agonist, and gamma-aminobutyric acid analogues), administered separately or in combinations, through the oral, intravenous, epidural, or regional (perineural) route. The beneficial effect of combined bupivacaine, diamorphine, and clonidine in reducing the risk of phantom limb pain was supported by only one study (level 3 evidence). Epidural and perineural infusions containing local anesthetic ± opiates are effective in treating acute perioperative pain, although not without potentially serious complications. Most studies were characterized by high drop-out rates because of disease-associated mortality.
CONCLUSIONS: There is no robust evidence supporting the use of pre-emptive analgesia to minimize the risk of chronic pain after amputation for critical ischemia of peripheral vascular disease. The methods used are, however, effective in treating acute postoperative pain.