We have compared the effects of gelatin, low molecular weight hydroxyethyl starch (HES) or albumin on tests of haemostasis and on the thrombelastogram in 42 ASA I patients undergoing total hip or knee replacement. Patients were allocated randomly to receive one of the three blood substitutes to obtain moderate intraoperative haemodilution. Blood loss and packed red cell infusion was the same in each group. A greater amount of gelatin was given (1.5 times the measured blood loss) because of its shorter half-life. There was a statistically significant but clinically negligible decrease in platelets count, prothrombin time and fibrinogen, and an increase in bleeding time in all groups. Platelets were slightly but significantly lower after HES. Haemodilution was comparable between groups. TEG showed a state of hypercoagulability in the gelatin group with a significant decrease in r, r + k and an increase in alpha angle.

Objective To assess the changes in overall coagulation status and define the degree of systemic fibrinolysis occurring in patients undergoing transurethral prostatectomy (TURP). Patients and methods Thirty patients undergoing TURP, 23 for benign prostatic hyperplasia and seven for prostatic carcinoma, were studied prospectively. Serial venous blood samples were taken using the two‐syringe technique. Samples were taken before, during and at intervals up to 72 h and 10–14 days after surgery. Thrombelastography (TEG) was performed on native whole blood samples. Peri‐operative blood loss was assessed, until the catheter was removed, by photometric estimation of the haemoglobin content of the irrigant fluid and the measurement of clot volume. Results There was no evidence of fibrinolysis (TEG Percentage Clot Lysis Ly60 >15%) in any patient over the whole peri‐operative period. There was a significant change in the mean TEG variables towards hypercoagulation from 3 h until 10–14 days post‐operatively, compared with the pre‐operative values (P<0.05). There was a significant correlation between blood loss and clot volume. Conclusion These results question the role of systemic fibrinolysis in primary and secondary haemorrhage following TURP and thus the rationale of using antifibrinolytics in these patients. The persistent hypercoagulable state post‐operatively indicates a possible role of hypercoagulability in clot retention.