Blood Measurements Flashcards
(24 cards)
What is Packed cell volume (PCV)?
This is the percentage volume of red blood cells present in a given sample of blood
Packed cell volume is also called ____________
Hematocrit
Hematocrit can be used to diagnose blood disorders such as
Anaemia
Hypoxia
Systemic ischemia
______________ and _______________ are the methods for PCV determination
Wintrobe method
Capillary tube method
What is hemostasis?
Stoppage of bleeding after a blood vessel is punctured, cut or damaged
What are the stages of hemostasis?
Vasoconstriction
Platelet plug formation
Blood clot formation
Fibrinolysis
What is Bleeding time?
Time interval between when a blood vessel gets punctured to when there is cessation of bleeding.
What is clotting time?
Time interval from oozing of blood from an injury or puncture to the formation of clot
What is the normal range for bleeding time?
3-6 minutes
What is the normal range for clotting time?
3-8 minutes
________________, ________________ and ________________ are methods of assessing bleeding time
Ivy’s method
Duke’s method
Simplate
What are the methods of assessing clotting time
Venous blood clotting time
Capillary blood clotting time
Drop method
_______________ and ______________ are the two important blood group determination systems
ABO
RH (Rhesus)
What is the clinical importance of knowing blood groups?
Important for blood transfusions and tissue transport
Used for settling parental disputes in medicolegal cases
_____________, ______________ and ______________ are reagents used in the estimation of prothrombin time
Plasma samples
Thromboplastin
Calcium chloride 0.025m
Thromboplastin used in the estimation of prothrombin time is obtained from ____________________
Human or rabbit brain tissue
Outline the method of prothrombin time estimation
A 75*10mm tube is placed in a water bath at 37°C
0.1ml of plasma is deposited inside
0.1ml of thromboplastin is added after 1 minute delay
0.1ml of calcium chloride 0.025m is added and the mixture is carefully mixed
Submerge lower end of the tube and start stopwatch
Fibrin clot formation marks the end point
Normal range for prothrombin time is about ______________
10 to 14 seconds
What is Erythrocyte sedimentation rate?
This is the rate at which red blood cells settle in a collected blood sample
Why do RBCs settle at the bottle of a blood sample instead of plasma?
This is because RBCs have a greater specific gravity than that of Plasma
2 factors affecting velocity of ESR
Sedimentation rate is directly proportional to the size of RBCs
Sedimentation rate is inversely proportional to the viscosity of plasma
Increased rouleaux formation rate increases sedimentation rate
ESR is used to ____________
Measure progress of chronic diseases e.g. Rheumatism, tuberculosis.
Normal range of ESR in males is ___________
0-5mm/hr
Normal range of ESR in females is ___________
0-7mm/hr
