[Agents for sedation and analgesia in the intensive care unit]

Sedation-analgesia for critically ill patients is usually performed with the combination of a sedative agent and an opioid. Midazolam and propofol are the agents most commonly used for sedation in ICU. The quality of the sedation is quite comparable with both agents, but pharmacokinetic properties of propofol allow a more rapid weaning process from mechanical ventilation. However, implementation of algorithms to adjust drug dosages reduces ventilator days and limits the kinetic differences between propofol and midazolam. Among the adverse events associated with propofol, propofol infusion syndrome is a rare but lethal aspect of propofol therapy. Opioids are the mainstay of analgesic therapy. They interact synergistically with hypnotics. Sufentanil, fentanyl and morphine are the most frequently used opioids. Remifentanil is an ultrashort acting opiate that does not appear to accumulate with prolonged use. The advent of remifentanil has allowed the use of analgesia-based sedation.