IRON PRE-LOAD FOR MAJOR JOINT REPLACEMENT

Patients undergoing total hip or knee replacement frequently receive b lood transfusion. Homologous blood transfusion carries appreciable ris ks and should therefore be reduced to a minimum. We have investi gated the use of preoperative oral iron supplements to optimize haemoglobin concentration and iron stores prior to surgery. All patients attendin g a preadmission clinic 4 weeks prior to primary hip or knee replaceme nt had a haemoglobin measurement. If the haemoglobin concentration (Hb ) was less than 12 g dL(-1) they were given a four week course of ferr ous sulphate. If it was greater than or equal to 12 g dL(-1) they were randomized to a control group or given a supplementation course of fe rrous sulphate. One hundred patients were seen. Of these 18 (18%) had haemoglobin less than 12 g dL(-1) and 16 were treated with iron. The m ean Hb was 10.8 g dL(-1) and mean cell volume (MCV) 86. These patients increased their Hb by a mean 1.1 g dL(-1) prior to admission (P = 000 8). MCV was the best predictor of response (r = -0 63, P < 0.02). This group dropped their haemoglobin by a mean 1.4 g dL(-1) in the first p ost-operative week. In the study groups there was no significant preop erative rise in Kb. However, the control group dropped their Hb by a m ean 1.3 g dL(-1) in the week following surgery compared with 0.4 g dL( -1) in the group which had received iron supplements (P < 0.001). We c onclude that at least 18% of patients attending for hip or knee replac ement in this region are frankly anaemic and benefit significantly fro m preoperative iron supplements over 4 weeks. Iron supplementation in patients without obvious anaemia protects against a fall in Hb during the immediate post-operative period, suggesting a widespread underlyin g depletion of iron stores in this group despite a normal Hb. Preopera tive iron supplements may reduce transfusion requirements as part of a co-ordinated strategy in this group of patients.