COMPARISON OF PENTOSAN POLYSULFATE SODIUM (NA-PPS) WITH A LOW-MOLECULAR-WEIGHT HEPARIN IN THE PREVENTION OF VENOUS THROMBOSIS AFTER ABDOMINAL-SURGERY

The equivalence of therapeutic effectiveness and safety of the low-mol ecular weight, heparin-like substance Pentosanpolysulphate-sodium (Na- PPS) and low-molecular weight heparin (Fragmin) for prophylaxis agains t deep leg vein thromboses was compared in a prospective, randomised s tudy in 749 patients after abdominal surgery. Patients were allocated to three groups: groups 1 (n = 250) received Na-PPS 50 mg s.c. once da ily, group 2 (n = 247) Na-PPS 50 mg s.c. twice daily and group 3 (n = 252) Fragmin in the recommended dosis of 16 mg s. c. once daily. All p atients wore anti-thrombosis stockings after their operations. Daily I -125-fibrinogen tests were used to assess the incidence of deep leg ve in thromboses in the first 7 postoperative days. The incidence of such thromboses was 2.8% (6 patients) in group 1, 1.2% (3 patients) in gro up 2 and 1.2% (3 patients) in group 3. No pulmonary emboli occurred. T he equivalence range was defined as the standard proportion (delta = 8 %). The incidence of deep leg vein thromboses in groups 1 and 2 was eq uivalent to that in group 3 (p < 0.0001, the one-sided 90% confidence interval was 3.36% for group 1 - Na-PPS once daily - and 1.84% for gro up 2 - Na-PPS twice daily). There was no significant difference betwee n the incidences in groups 1 and 2 (p = 0.2579). These results show th at Na-PPS is equivalent to low-molecular weight heparin with respect t o the incidence (prophylaxis) of deep leg vein thromboses. Treatment t olerance was equally good in all groups, as was the incidence of intra - and postoperative blood loss, wound haematomas and blood transfusion s. Na-PPS (50 mg s. c. once daily) as postoperative prophylaxis agains t deep leg vein thrombosis in patients wearing anti-thrombosis stockin gs after abdominal surgery is thus equally effective and safe as low-m olecular weight heparin (in the recommended dosis of 16 mg s. c. once daily).