The burden of acute postoperative pain and the potential role of the COX-2-specific inhibitors.

Pain has been recognized as a problem of global proportions, and postoperative pain is one of the most common types of pain. Postoperative pain is acute and, although it is preventable and/or treatable, it is often undertreated. Lack of appropriate analgesic management has significant impact on clinical and economic outcomes. Negative clinical outcomes of inadequately managed acute postoperative pain include extended hospitalization, compromised prognosis, higher morbidity and mortality, and the development of a chronic pain state as a result of neuronal plasticity. Although estimating the economic burden of postoperative pain is difficult, this burden is considerable and results from direct costs due to excess health-care resource use, as well as indirect costs due to reduced patient functionality and productivity. These latter factors also have a significant adverse impact on patients' quality of life and may be associated with the development of depression and anxiety. Thus, improved clinical outcomes are dependent not only on the availability of effective drugs but also on their appropriate utilization. A multimodal approach incorporating different drugs and techniques is effective in reducing postoperative pain but is limited by the currently available therapies. The efficacy of opioids is well established, but there are concerns about dependency, respiratory depression and side-effects, which patients often find intolerable. Non-steroidal anti-inflammatory drugs (NSAIDs) are effective as adjunctive medication in a multimodal regimen but are associated with side-effects, such as platelet dysfunction and renal and gastrointestinal toxicity, that have special clinical significance in patients undergoing surgical procedures. Cyclooxygenase-2-specific inhibitors such as celecoxib, rofecoxib and valdecoxib, were developed to provide the efficacy of non-specific NSAIDs while limiting associated toxicity. These agents have demonstrated analgesic efficacy and an opioid-sparing effect in a variety of surgical procedures, suggesting their value as an alternative to non-specific NSAIDs. Further studies are needed to determine the impact of these drugs on clinical and economic outcomes when used in a programme of postsurgical pain management.