A Comparison of the Effects between Acetaminophen and Flurbiprofen after Lumbar Spinal Fusion Surgery

Aims: Introduction: Spinal fusion surgery is often associated with severe postoperative pain. This study aimed to determine whether intravenous acetaminophen produces equivalent analgesic effects to flurbiprofen under fentanyl patient-controlled analgesia (PCA) after one-level lumbar spinal fusion surgery.

Study Design: Rondomized controlled trial.

Place and Duration of Study: Department of Anesthesia, Nagasaki Rosai Hospital, Sasebo Japan, between October 2015 to March 2017.

Methodology: We studied 75 patients who underwent one-level lumbar spinal fusion surgery. Patients were randomly allocated to 1 of 3 groups: Group A (n = 25), which received 15 mg/kg acetaminophen intravenously every 6 hr. Group F (n = 25), which received 1 mg/kg flurbiprofen intravenously every 8 hr; and Group C (n = 25), which received saline every 6 hr as the control. Each drug was started from prior to skin closure to 24 hr after surgery. All patients received fentanyl at a fixed dose of 0.33 μg/kg/hr continuously after a bolus administration of 250 μg fentanyl. A bolus of 0.33 μg/kg of fentanyl was administered on demand by PCA (lockout interval 15 min). Postoperative pain was evaluated using a numerical rating scale (NRS) at 1, 2, 6, 12, 24 hr postoperatively and fentanyl consumption was recorded for 6 and 24 hr after surgery. The frequency of bolus fentanyl administration were also recorded.

Results: There were no significant differences in NRS scores among the 3 groups. Acetaminophen and flurbiprofen did not show opioid sparing-effects under fentanyl PCA. However, the frequency of fentanyl boluses were significantly less in group A than in group C.

Conclusions: Acetaminophen may produce equivalent analgesic effects to flurbiprofen after one-level lumbar spinal fusion surgery.