UNIT 1 PLATELETS Flashcards
Uncontrolled platelet and hemostatic activation is
responsible for:
○ Deep vein thrombosis
○ Pulmonary emboli
○ Acute myocardial infarctions (heart attacks),
○ Cerebrovascular accidents (strokes),
○ Peripheral artery disease,
○ Repeated spontaneous abortions
(miscarriages)
A low platelet count, , is a common consequence of
drug treatment and may be life threatening
Thrombocytopenia
s usually accompanied by easy
bruising and uncontrolled hemorrhage.
Thrombocytopenia
s a rare life threatening malignant condition characterized by extremely high platelet counts and uncontrolled platelet production.
Essential thrombocythemia
Platelets size
2 to 4 µm in diameter
round, anucleated,slightly granular
platelet
accounts for many
hemorrhage-related emergency department visits.
Thrombocytopenia
platelets are made of
pieces of a
bone marrow cell known as a megakaryocyte
(fragments of Megakaryocytes)
Reference range for platelets:
150-450 K/cu.mm.
Platelets rapidly adhere to the surfaces of damaged blood
vessels, form aggregates with neighboring platelets to
plug the vessels, and secrete proteins and small
molecules that trigger
thrombosis, or clot formation
elevated platelet counts, signal
inflammation or trauma but convey modest intrinsic
significance.
Thrombocytosis
Platelets are the major cells that control _________, a
series of cellular and plasma-based mechanisms that seal
wounds, repair vessel walls, and maintain vascular patency (unimpeded blood flow).
hemostasis
ability to aggregate and adhere
platelet
means associated with clotting
“Thrombo-”
are true blood cells that
maintain blood vessel integrity by initiating vessel wall
repairs.
Platelets, or thrombocytes
