2006 Annual Scientific Meeting - CLICK FOR PROGRAMME

Remifentanil for Sedation in Intensive Care

Kevin Gunning, Addenbrooke’s Hospital, Cambridge

Sedation is one of the most commonly used therapies in intensive care and nearly all patients will receive some form of sedation during their stay on the ICU. Most national intensive care societies have published guidelines for sedation. Despite this sedation is not always done well and there is no consensus as to the best drugs or regimen. Patients also vary in their need and response to the drugs used for sedation. Traditionally sedation has been based on hypnotic drugs such as midazolam or propofol, with bolus doses or an infusion of long acting opioids used to control pain. However, studies have shown that pain is not well managed on the ICU, with between 40-60% of patients reporting moderate to severe pain during their stay. “Doing everything possible to control pain”, was mentioned by 76% of respondents in the CoBaTrICE survey of patients and relatives views on the competencies essential in an intensivist. Many patients in intensive care have impaired renal or hepatic function resulting in an unpredictable duration of action when traditional drugs with active metabolites are used.

The licensing of the of the potent, short acting opioid remifentanil for sedation in critically ill patients for up to 72 hours has allowed us to change the way we sedate patients in intensive care. Remifentanil has many characteristics that make it suitable for use in intensive care. It has a rapid onset of action and is easy to titrate making it simple to achieve a desired level of sedation. It provides good analgesia, reduces the need for hypnosis and improves the patient’s experience of intensive care. Communication is therefore better and patients can be comfortable and awake on a ventilator. It is possible that this could lead to a reduction in posttraumatic stress disorder seen after intensive care. Good analgesia can be provided for painful procedures such as chest drain insertion, or percutaneous tracheostomy without the risk of an overdose. The short context sensitive half life and metabolism that is independent of renal and hepatic function mean that the drug wears off in a predictable manner. Weaning from the ventilator is facilitated by this rapid offset time, allowing more efficient use of beds when the ICU is busy. There is increasing evidence that the duration of mechanical ventilation is shorter with the use of analgesia-based sedation in both long and short stay patients. Dahaba showed a significant reduction in the duration of ventilation in a study of 40 postoperative patients. In an international study of 150 patients ventilated for up to 10 days, Breen showed a significant reduction in duration of mechanical ventilation and time from weaning to extubation.

The rapid offset of action however, means that staff must be trained to think about analgesia before stopping remifentanil in patients with on going pain.

With its unique pharmacological profile, remifentanil has enabled us to make analgesia the cornerstone of sedation and is a cost effective way of providing sedation in ventilated critically ill patients.