Intravenous Acetaminophen Significantly Reduces Incidence of Postoperative Delirium

Intravenous acetaminophen significantly reduced the incidence of postoperative delirium following coronary artery bypass graft (CABG) procedures in patients aged older than 60 years, according to a study published in JAMA.

The findings of a single-centre trial may represent the first steps toward a therapeutic intervention for the prevention of postoperative delirium.

“Currently, IV acetaminophen administration is considered an expensive intervention, and there is significant variation in pain management following cardiac surgery,” said Balachundhar Subramainam, MD, Beth Israel Deaconess Medical Center, Boston, Massachusetts. “If our findings are replicated in a larger, multicentre study, postoperative intravenous administration of acetaminophen could become a standard of care in all cardiac surgical patients and could be incorporated in cardiac surgery recovery protocols.”

The researchers enrolled 120 patients aged 60 years or older who underwent CABG surgery with or without valve repair at Beth Israel Deaconess Medical Center between September 2015 and April 2018.

To evaluate the effect of IV acetaminophen on postoperative delirium, the researchers randomised patients into 1 of 4 groups receiving different combinations of sedation and pain medication after surgery.

Patients were assigned to receive dexmedetomidine with IV acetaminophen (n = 29), dexmedetomidine plus placebo (n = 30), propofol plus acetaminophen (n = 31), or propofol plus placebo (n = 30).

Patients treated with acetaminophen demonstrated a significant reduction in in-hospital delirium. Only 10% of the group given acetaminophen experienced signs of delirium, compared with 28% of those given placebo.

Moreover, those given acetaminophen also were more likely to have shorter stays in the intensive care unit and less breakthrough pain. Patients who did experience delirium had shorter bouts of the acute confusion.

In addition to decreasing the incidence of delirium, adding acetaminophen to postoperative care also reduced the need for opioid painkillers in these patients.

“Postoperative pain is known to increase the risk for postoperative delirium, as is the use of opioids to manage postoperative pain,” said Dr. Subramaniam. “We found that the use of IV acetaminophen provided effective pain control, and we observed a noticeable sparing of opioids in the postoperative period with decreased duration of delirium and intensive care unit length of stay.”