PAracetamol and NSAID in Combination: A Randomised, Blinded, Parallel, 4-group Clinical Trial

Trial name: PAracetamol and NSAID in combination: A randomised, blinded, parallel, 4-group clinical trial Trial acronym: PANSAID Background: Effective postoperative pain management is essential for the well-being and rehabilitation of the surgical patient. No "gold standard" exists after total hip arthroplasty (THA) and combinations of different non-opioid medications are used with virtually no evidence for additional analgesic efficacy compared to monotherapy. Objectives: The objective of this trial is to investigate the analgesic effects and safety of paracetamol and ibuprofen and their combination in different dosages after THA. Intervention: Patients are randomised to 4 groups: A) paracetamol 1 g x 4 and ibuprofen 400 mg x 4; B) paracetamol 1 g x 4 and placebo (ibuprofen); C) placebo (paracetamol) and ibuprofen 400 mg x 4; and D) paracetamol 0,5 g x 4 and ibuprofen 200 mg. Design: Placebo controlled, parallel 4-group, multicentre trial with adequate centralised computer-generated allocation sequence and allocation concealment with varying block size and stratification by site. Blinding of assessor, investigator, caregivers, patients, and statisticians. Sample size: 556 eligible patients are needed to detect a difference of 10 mg morphine the first postoperative day with a standard deviation of 20 mg and a type 1 error rate of 0,004 (two-sided) and a type 2 error rate of 0,10.