Reduced platelet function and role of drugs in acute gastrointestinal bleeding.
Gastrointestinal (GI) bleeding may be caused by a constitutive bleeding disposition or drug-induced inhibition of hemostasis. Platelet function in patients with ongoing GI bleeding is unknown. The aim of this study was to investigate platelet function in patients with acute GI bleeding. Patients (n=35) presenting with acute GI bleeding (hematemesis or melena) were recruited. For comparison, 13 patients treated with aspirin and 11 patients treated with clopidogrel without GI bleeding and 27 healthy controls were studied. Platelet function was measured by whole-blood aggregation and flow cytometry. Coagulation function was measured with calibrated automated thrombography. Platelet aggregation and P-selectin expression were significantly lower after arachidonic acid stimulation in GI bleeding patients than in healthy subjects (p≤0.05). Collagen-induced P-selectin expression was significantly reduced in patients using anti-platelet drugs (p=0.02) and in many patients not using anti-platelet drugs. Thrombin generation, measured by calibrated automated thrombography, was only reduced in patients on warfarin treatment. In conclusion, platelet function is reduced in acute GI bleeding patients and a considerable proportion appears to be related to drug use.
Department of Pharmacology, Oslo University Hospital, Ullevål, Kirkeveien 166, Oslo, Norway. m.k.kringen@medisin.uio.no
Marianne K
MK
Kringen
Sigrid
S
Narum
Idar
I
Lygren
Ingebjørg
I
Seljeflot
Per-Morten
PM
Sandset
Anne-Marie S
AM
Trøseid
Per W
PW
Johansen
Odd
O
Brørs
Mette R
MR
Holthe
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000009:adverse effects; D015703:Antigens, CD / Q000097:blood; D016718:Arachidonic Acid / Q000494:pharmacology; D001777:Blood Coagulation / Q000187:drug effects; D001792:Blood Platelets / Q000187:drug effects* / Q000378:metabolism; D003094:Collagen / Q000494:pharmacology; D005260:Female; D006471:Gastrointestinal Hemorrhage / Q000139:chemically induced* / Q000378:metabolism / Q000503:physiopathology; D006396:Hematemesis / Q000209:etiology; D006487:Hemostasis / Q000187:drug effects*; D006801:Humans; D008297:Male; D008551:Melena / Q000209:etiology; D008875:Middle Aged; D019007:P-Selectin / Q000097:blood; D010974:Platelet Aggregation / Q000187:drug effects; D010975:Platelet Aggregation Inhibitors / Q000009:adverse effects*; D010980:Platelet Membrane Glycoproteins; D012720:Severity of Illness Index; D060149:Tetraspanin 30
D000925:Anticoagulants; D015703:Antigens, CD; C554586:CD63 protein, human; D019007:P-Selectin; D010975:Platelet Aggregation Inhibitors; D010980:Platelet Membrane Glycoproteins; D060149:Tetraspanin 30; D016718:Arachidonic Acid; D003094:Collagen