Intranasal Tapentadol Versus Intravenous Paracetamol for Postoperative Analgesia in Lower Limb Orthopaedic Surgeries Under Spinal Anaesthesia: A Single Blind RCT.

Objective: We aimed to compare the analgesic effectiveness of intranasal tapentadol nasal spray 44.5 mg and intravenous (IV) paracetamol 1 gm during the postoperative period in patients undergoing lower limb orthopedic surgeries under spinal anesthesia.

Methods: This prospective, randomized, single-blind clinical trial was carried out in a tertiary care teaching hospital. Patients aged between 18 and 60 years of physical status ASA grade 1-3 were included in the study. Postoperative pain scores were measured using the visual analog scale (VAS) in centimeters (cm) every 12 hours in 37 patients per group. The patients were administered either intranasal tapentadol or IV paracetamol every 6 hours for 72 hours, beginning 3 hours after surgery.

Results: There was a significant group by intervention effect favoring intranasal tapentadol, suggesting a greater reduction in VAS pain scores after the intervention at 72 hours (estimate: -1.58 cm; SE:0.2; P<0.001). Group by time effect for all the measured time frames, except for 36 hours, favored intranasal tapentadol with estimated values for greater reduction in VAS pain scores ranging from -0.8 cm to -1.6 cm.

Discussion: The results of the present study suggests that intranasal tapentadol results in a greater reduction of postoperative pain compared with IV paracetamol in lower limb orthopedic surgeries. The ease of administration of tapentadol may make it a preferred option over IV paracetamol in such surgeries.