OBJECTIVE To assess the efficiency of corticosteroids and preoperative acute normovolaemic haemodilution (PANHD) in reducing postoperative inflammation after maxillofacial surgery. STUDY DESIGN Randomized clinical trial. PATIENTS Thirty-two patients scheduled to undergo maxillary osteotomy for facial dysmorphia were randomized into four groups of eight (PANHD or not; corticosteroids or not). METHODS PANHD decreased haematocrit to 30%. In the corticosteroid groups, methylprednisolone
1.5 mg.kg-1 was given intravenously at the beginning of surgery (after PANHD in haemodiluted group), and after surgery, 1.5 mg.kg-1 iv daily for three days. Postoperative inflammation was assessed with an X-Ray technique (radiotelemetry) providing data on tissue thickness (extent of facial oedema), and by measurement of plasma concentrations of four acute phase proteins during the first postoperative week. RESULTS No change in facial oedema and in acute phase proteins occurred with PANHD. Corticosteroids decreased postoperative oedema and acute phase proteins. CONCLUSION Corticosteroids decrease postoperative inflammation after maxillofacial surgery but not PANHD.