Plasma Storage and Coagulation Testing Flashcards
platelet poor plasma may be stored at ___ or lower for at least several weeks without loss of most factors
-40 c
the liquid should initially be frozen very quickly using
liquid nitrogen or temp at -80 to -40 C
when thawing frozen plasma it should be done rapidly in a ___ or ___
37 C incubator or water bath
cannot be refrozen
plasma
most coagulation studies are carried out at
37 C
it should be noted that specimens incubated in ___ take slightly longer to reach 37 C
dry heat
the temperature of the incubator should not fluctuate more than
(±) 0.5 C
accurate ___ of clotting times is extremely important
timing
4 general techniques in widespread use for reading the end point of clotting procedures
tilt tube, nichrome wire loop, moving probe, optical density
requires gentle tilting of the tube back and forth at the rate of about once per second until a fibrin web is formed
tilt tube
employs the use of a wire loop that is passed through the mixture at the rate of two sweeps per second until a formed clot adheres to the loop
nichrome wire loop
in the first two techniques ___ is important
light source without glare
facilitates the end point readings
black background
the third and fourth procedure employ the use of
automation
a clot is detected either by use of a ____ immersed in the mixture
moviing probe
