Do Postoperative Pain Management Techniques Influence Postoperative Delirium?

Postoperative delirium (POD) is a common postoperative complication in older patients and may increase morbidity and mortality. The etiology of POD is multifactorial and suggested to be the result of interactions between patient vulnerability (predisposing factors) and exposure to precipitating factors. Poorly controlled postoperative pain has been identified as a precipitating risk factor for POD. However, effective pain management strategies to reduce incidence of POD are still far from being elucidated. Postoperative pain management techniques in older patients have changed substantially in recent years; for example, peripheral nerve blocks and multimodal analgesia have become common adjunctive techniques. It is unclear; however, whether these pain control management techniques can change the incidence of POD. In this review, we will focus on the English-language literature published last 30 years investigating the association between pain management strategies and incidence of POD. We will review opioid analgesics which are the most commonly used postoperative pain medications for major surgery. In addition, we will highlight pain control techniques including intravenous patient-controlled analgesia, epidural analgesia, peripheral nerve blocks, multimodal analgesia, and structured pain management protocols in multi-component delirium intervention. Furthermore, pain control in cognitively impaired patients will be reviewed. © 2014, Springer Science + Business Media New York.