Intravenous Acetaminophen Does Not Decrease Persistent Surgical Pain After Cardiac Surgery

The authors investigated the hypothesis that perioperative acetaminophen reduces incisional pain at 30 and 90 days.

This was a prospective, randomized, double-blind trial.

Tertiary-care hospital (single center) cardiac surgery unit.

Patients undergoing cardiac surgery via median sternotomy.

Patients were assigned randomly to intravenous (IV) acetaminophen or IV placebo. Patients were given 4 doses of 1 g of IV acetaminophen or an equal volume of saline placebo over 15 minutes every 6 hours for 24 hours starting in the operating room after sternal closure.

Study participants were assessed by phone for incisional pain severity 30 and 90 days after surgery. Those reporting any incisional pain were asked to complete the Neuropathic Pain Questionnaire-Short Form and the modified Brief Pain Inventory. Patients were compared on 30- and 90-day incisional pain severity using separate multivariable linear regression models. IV acetaminophen had no effect on 30- and 90-day incisional pain, with an estimated difference in means (confidence interval) of 0.06 (-0.87 to 0.99) at 30 days (p = 0.88) and 0.07 (-0.71 to 0.86) at 90 days (p = 0.83). Low pain severity, neuropathic pain, and interference at both 30 and 90 days after surgery, regardless of treatment group, were observed.

IV acetaminophen did not reduce the incidence or intensity of incisional pain at 30 days and 90 days after surgery.