* under 18 years old * pregnant women * known allergy to heparin * participant in another clinical trial that is not approved for joint enrollment. * aptt\> 120 seconds, not due to anticoagulant therapy. * platelet count \<20 x 109 per l * lung bleeding. * uncontrolled bleeding * advanced neurological impairment * advanced oncological disease

* under 18 years old * pregnant women * known allergy to heparin * participant in another clinical trial that is not approved for joint enrollment. * aptt\> 120 seconds, not due to anticoagulant therapy. * platelet count \<20 x 109 per l * lung bleeding. * uncontrolled bleeding * advanced neurological impairment * advanced oncological disease

- under 18 years old - pregnant women - known allergy to heparin - participant in another clinical trial that is not approved for joint enrollment. - aptt> 120 seconds, not due to anticoagulant therapy. - platelet count <20 x 109 per l - lung bleeding. - uncontrolled bleeding - advanced neurological impairment - advanced oncological disease

- under 18 years old - pregnant women - known allergy to heparin - participant in another clinical trial that is not approved for joint enrollment. - aptt> 120 seconds, not due to anticoagulant therapy. - platelet count <20 x 109 per l - lung bleeding. - uncontrolled bleeding - advanced neurological impairment - advanced oncological disease