Delirium, or severe confusion and disorientation, is often experienced by critically ill patients, and although causality between delirium and mortality is not established, critically ill patients who develop delirium are up to three times more likely to die by 6 months than are those who do not. Delirium may also add to the distress and discomfort experienced by both a critically ill patient and their family.
A group of researchers led by Dr Valerie Page tested the effect of haloperidol on delirium in 141 critically ill patients on artificial ventilation in Watford General Hospital, Watford, UK. Just over half (71) of the patients received haloperidol to treat delirium, with the remaining 70 patients receiving a placebo.
Haloperidol doses were based on existing clinical practice for the management of delirium, and patients were carefully monitored for adverse reactions to the drug, as well as over-sedation. Both the clinicians administering the study drug, and the researchers who analysed the data, were not aware of patients' placement in the control or study groups.
The researchers found that compared to the placebo group, haloperidol had no effect on the number of days spent without delirium or without coma, up to 14 days after the study began. Nor did the drug affect mortality rates, length of stay in critical care or hospital, or number of ventilator-free days up to 28 days after the study began.
Despite its lack of effectiveness in treating delirium, the trial results show that patients given haloperidol seemed to require less sedation than those given placebo, suggesting that the drug may still be useful for short-term management of acute agitation.
"Despite a limited evidence base, increasing numbers of patients are being exposed to haloperidol for the management of delirium," says Dr Page. "Our results suggest a commonly used haloperidol dose regimen does not decrease delirium in critically ill patients requiring mechanical ventilation, when commenced early during ICU stay."*
"Although haloperidol can be used safely in this population of patients, our results do not support the idea that haloperidol modifies duration of delirium in critically ill patients. Identification of a drug to prevent or reduce delirium and improve adverse outcomes, including in the intensive care setting, needs to be a high priority within delirium research."*
"Although haloperidol is used commonly, its use to treat delirium does not seem to be justified," Dr Yoanna Skrobik, Lise and Jean Saine Critical Care Chair at the University of Montreal in Canada, writes in a linked Comment. Dr Skrobik goes on to question whether delirium even needs to be treated with drugs, adding that, "Only non-pharmacological prevention measures have been shown to reduce its occurrence in critically ill patients.
Non-pharmacological interventions are effective in numerous psychiatric and psychological disturbances. The challenge lies in the distress delirium symptoms cause in caregivers…We should be asking ourselves, are we treating the patients or our own discomfort?"
Explore further: Delirium following cardiac surgery common in older patients