Abstract
All critically ill adult patients in intensive care units (ICU) typically experience pain. Critically ill adults suffer pain of different intensities. It depends on individual characteristics, specific procedural interventions, and underlying diseases. Inadequate management of acute pain is a risk factor for the emergence of chronic pain, where the incidence is up to 33% into the ICU survivor population. For the management of pain, agitation, and delirium, several coexisting clinical practice guidelines have been published. The first problem is that the patient recovered in intensive care unit should not be able to communicate its pain state. Opioids are the analgesic drugs of choice in critically ill patients with non-neuropathic pain. All intravenous opioids have the same effects, respecting the equianalgesic table. Observational research has shown that opioids are the main analgesic treatment in over 80% of mechanically ventilated patients. It is interesting that opioid consumption in an ICU and the memory of painful experience are linked to the development of post-traumatic stress disorder after ICU discharge. In order to reduce the side effects and maintain analgesia, it is useful to associate adjuvant medications with opioids. An opportunity to improve patients' experience in an ICU is to manage pain through multimodal approaches.