WEEK 10 - lab eval of fibrinolysis and anticoagulant therapy Flashcards
is the enzymatic breakdown of fibrin in blood clots.
fibrinolysis
star of fibrinolysis
plasmin
(including activators and inhibitors) cuts the fibrin mesh at various places, leading to the production of
circulating fragments that are cleared by other proteases.
plasmin
The endogenous plasmin-mediated process of dissolving a formed thrombus is denoted __
fibrinolysis
principle of whole blood clot lysis time
A clot is dissolved as a result of plasmin activity (no plasmin, no dissolution). Normally, this does not
occur in less than 72 hours because of the presence of plasma inhibitors which inactivate plasmin as it forms.
it assesses body’s ability to dissolve a blood clot and assess the fibrinolyutic system that is responsible in breaking clots
whole blood clot lysis time
if the lysis of clot occurs less than 72 hours it suggest that
our fibrinolytic system is enhanced due to certain conditions
conditions that enhance fibrinolytic activity of WBCLT
hyperfibrinolysis
liver disease
malignancy/cancer
systemic disorders
principle of diluted blood clot lysis time
plasmin inhibitors loose activity on dilution. In this method, whole blood is diluted with a buffer solution and clotted by the addition of thrombin. Then the clot is observed to lysis
Three buffer solutions that can be used in DCLT
o Phosphate buffer (PBS) – most common
o Sodium acetate
o Sodium chloride
purpose of diluted blood in DCLT
makes the blood more sensitive and the dilution reduces the concentration of clotting factors and inhibitors (plasmin inhibitors) to be observed readily ng
normal value of DCLT
should not lyse less than 6-10 hrs
shorten lysis suggests
increase fibrinolysis in DCLT observe in conditions such as
DIC - disseminated intravascular coagulation
liver disease
cancer
prolonged lysis time suggest in DCLT
defective fibrinolysis or excessive inhibitions seen in conditions where clot breakdown is impaired
Blood is collected in an anticoagulant, centrifuged and the plasma is recalcified, and checked for clot lysis
PLASMA CLOT LYSIS TIME (PCLT)
steps for plasma clot lysis time
collect blood
centri
recalcified plasma - adding calcium
check for clot formation
observe lysis
incubation
are proteins that can be precipitated when plasma is acidified by 1% acetic acid
euglobulin
fraction of plasma protein
eugloblulin
A screening procedure for the measurement of fibrinolytic activity (overall fibrinolysis).
EUGLOBULIN CLOT LYSIS TIME (ECLT)
euglobulins are fraction of plasma protein which is composed of
plasminogen, plasminogen activator and fibrinogen
normal value of whole blood clot lysis time
lysis after 24 hrs
this test is more sensitive than the clot lysis time
euglobulin clot lysis time
increase fibrinolytic activity of ECLT is seen in
associated with circulatory collapse
adrenalin injection
sudden death
pulmonary surgery
pyrogen reaction
obstetric complication
extreme stress
increased fibrinolytic activity is observed in euglobulin clot lysis time such as the condition associated with circulatory collapse, what are the conditions or example of scenario where it is observed?
shock
circulatory system fail