Postoperative analgesia and sedation in the adult intensive care unit: a guide to drug selection

Abstract

An essential goal of all critical care physicians should be to maintain an optimal level of pain control and sedation for their patients. This has become increasingly important because of evidence showing that the combined use of sedatives and analgesics may ameliorate the detrimental stress response in critically ill patients. Unfortunately, both pain and anxiety are subjective and difficult to measure, thereby limiting our ability to analyse these states and making management more challenging. Although there is still a lack of high quality, randomised, prospective, controlled trials comparing agents, monitoring techniques and scoring scales, several societies have come together to publish some clinical practice guidelines for sedation and analgesia. Recommended opioids are fentanyl or hydromorphone for short-term use, and morphine or hydromorphone for longer-term therapy. Midazolam or diazepam are recommended for sedation of the acutely agitated patient, while lorazepam is recommended for longer infusions. Propofol is preferred when rapid awakening is desired. The challenge for critical care physicians is to use these medications to provide comfort and safety without increasing morbidity or mortality. Most studies support the use of protocols in order to help achieve these goals. The bottom line is that most protocols end up stressing some common issues. These include daily cessation of drugs to evaluate the patient and frequent reassessment of the level of sedation required by each specific patient. Much is still unknown about the long-term effects of sedative and analgesic drugs used as infusions that may last from days to weeks to months. Hopefully, as more studies are performed, we will have more defined clinical end-points, newer drugs with rapid onset and offset and no active metabolites, and decreased morbidity and mortality for our patients.