A patient is on aspirin, what will be the finding?
Answer is A (Prolonged bleeding time (BT) Bleeding time is indicative of function of platelets. Aspirin ingestion results in defective platelet function and hence the deranged parameter will be Bleeding time. PT, APTT and Clotting time (CT) are parameters of coagulation defects, and will be normal in isolated disorders of platelet function. 'Ingestion of Aspirin and other Nonsteroidal Antiinflammatory drugs, significantly prolongs the bleeding time'. `Aspirin even in small doses irreversibly inhibits T xA2 synthesis by platelets. Thus it interferes with platelet aggregation and bleeding time is prolonged to nearly twice the normal value'- Note: Aspirin irreversibly inhibits COX -1 and COX - 2. (Harrison) COX inhibition leads to prevention of TXA2 synthesis and impairment of platelet secretion and aggregation The effect of aspirin on platelet function occur within 1 hour and lasts for the duration of the affected platelet's life span ie. 1 week.Q
Prolonged BT
Prolonged PT
Prolonged APTT
Prolonged CT