Acute pain is a significant problem for inpatients and can occur secondary to acute illness or disease processes, trauma, or operative procedures in both adults and children. In the post-operative period, 80% of individuals suffer from post-operative pain with almost all describing it as moderate to severe. Physiologically, pain serves to alert individuals to tissue damage and to prevent further harm. However, in the acute inpatient setting, it often serves no useful purpose. Pain activates the sympathetic nervous system, increasing blood pressure, cardiac workload and respiratory rate. It impairs recovery by reducing mobility and physical activity. In many instances acute pain coincides with a patient being unable to take oral medication and at such times it is important to have access to appropriate intravenous treatments. This is usually only required for short periods in the acute situation e.g. post operative.
Opioid analgesics are a mainstay in the management post-operative and acute pain in the inpatient setting. However adverse effects including respiratory depression, sedation, allergic reactions and gastrointestinal events often limit their use. Opioids are useful in mitigating the sensation of pain, but provide no benefits to the underlying disease process. Adjunctive agents for pain including non-steroidal anti-inflammatory agents (NSAIDs) may be used in combination with opioids. Combination therapy may help mitigate the side effects of both agents by reducing the total dose required. The anti-inflammatory properties of NSAIDs may also be useful in promoting healing and resolution of pain. NSAIDs inhibit the production of COX-1 and COX-2 enzymes and prevent the sensitization of pain receptors at the site of injury.