Hospital computerised records were reviewed to identify patients who had undergone splenectomy, then chart their platelet count before and for the 5 days after the operation. A pre-operative platelet count less than 100 x 10(9).l-1 occurred in 66% of leukaemia (n = 35), 56% of lymphoma (n = 41) and 5% of solid tumour (n = 39) patients. Platelet supplementation prior to epidural catheter insertion may reduce the risks of spinal bleeding. However, accidental catheter removal during a postoperative period of thrombocytopenia may lead to formation of an epidural haematoma. The lowest postoperative platelet count was less than 100 x 10(9).l-1 in 66% of leukaemia, 27% of lymphoma and 13% of solid tumour patients. Platelet counts varied considerably, so predicting an individual patient's postoperative nadir from the pre-operative count would be impossible. Consequently, placement of an epidural catheter in many of these patients could expose them to an increased risk of spinal bleeding if the catheter is removed accidentally.