Blood Coagulation and Wound Healing Part 2 Flashcards
wound healing
complex process in which skin or other tissue repairs itself after injury
the classic model of wound healing can be divided into four sequential overlapping phases:
hemostasis
inflammatory
proliferative
remodeling
hemostasis occurs within
minutes after injury
hemostasis
platelets aggregate at the injury site to form a fibrin clot, which acts to control bleeding
inflammatory phase
bacteria and debris are phagocystosed and removed from the wound site. factors are released that cause migration and division of cells involved in the proliferative phase
proliferative phase
angiogenesis, collagen deposition, granulation, tissue formation, epithelialization, and wound contraction
remodeling phase
collagen is remodeled and realigned along tension force lines and cells no longer needed are removed by apoptosis
what is present during hemostasis? (4)
clot
platelet
RBC
scab
what is present during inflammation? (2)
macrophage
neutrophil
what is present during proliferation phase? (3)
granulation tissue
fibroblast
myofibroblast
remodeling phase
collagen fiber
what are some examples of diseases which interfere with wound healing progression? (4)
diabetes
venous or arterial disease
old age
infection
how are growth factors regulated? (2)
specially
temporally
ACD
acid citrate dextrose solution
what is ACD anticoagulant?
a solution of citric acid, sodium citrate, and dextrose in water
how does citrate work as an anticoagulant?
citrate and EDTA. citrate, in the form of sodium citrate or acid-citrate-dextrose is used to disrupt the coagulation cascade and prevent clotting. these citrate compounds bind to the calcium in the blood. by reducing the amount of calcium, there will be no regulation of the binding and the cascade cannot begin
prothrombin time (PT)
a test used to help detect and diagnose a bleeding disorder or excessive clotting disorder
the international normalized ratio (INR) is calculated from a
PT result
what is the INR used for
to monitor how well the blood-thinning medication (anticoagulant) warfarin (Coumadin) is working to prevent blood coagulation
prothrombin time is a measure of the integrity of
the extrinsic and final common pathways of the coagulation cascade
the extrinsic and final common pathways of the coagulation cascade consists of tissue factor and factors (5)
VII II (prothrombin) V X fibrinogen
PT is usually measured in
seconds
PT is compared to a
normal range that reflects PT values in healthy individuals
Because the reagents used to perform the PT test vary from one laboratory to another and even within the same laboratory over time, the normal ranges also
will fluctuate
To standardize results across different laboratories in the U.S. and the world, a World Health Organization (WHO) committee developed and recommended the use of the
Internationalized Normalized Ratio (INR)
INR ratio allows for
easier comparisons of test results from different laboratories
when is INR used?
if you take blood-thinning medications
normal INR in healthy people
1.1