Effect of low-dose heparin on the phagocytic and catabolic function in the reticulo-endothelial system in man during surgery.

The effect of subcutaneous low-dose heparin prophylaxis on the phagocytic and catabolic functions of the reticuloendothelial system (RES) was studied in 10 patients undergoing elective cholecystectomy. The patients were divided into two groups; 5 patients receiving 5 000 units of heparin preoperatively and every 12 hours following the operation and 5 patients given saline at the corresponding time. Each patient served as his own control, when the RES function was tested twice with microaggregated human serum albumin labelled with 125I as a test substance. There was an enhanced phagocytic activity and a correspondingly raised catabolic activity of the RES in patients treated with heparin. The reasons for this are discussed. The results indicate that heparin in low doses has a favourable effect on the RES.