Diseases of the Blood Flashcards
What is a FBC? (Full blood count)
A measure of all the cells in the blood.
What is a HCT? (Haematocrit)
The proportion of cells to liquid.
What does a low HCT mean?
Losing blood cells quicker than you can replenish them.
What does a high HCT mean?
Lots of blood cells create a viscous blood which is prone to clotting.
What is the MCV? (Mean cell volume?)
The average size of the cells.
Define anaemia.
Low amounts of haemoglobin in the blood.
In the form of:
Lots of RBC with little haemoglobin.
Small amounts of RBC with lost of haemoglobin.
What is leukopenia?
Low white blood cell count .
What is thrombocytopenia?
Low platelet count. (Platelets create clotting capacity)
What is pancytopenia?
Reduction in all cells of the blood.
Can be an indication of bone marrow issues - where blood cells formed.
What is polycythaemia?
Raised levels of haemoglobin.
Define leukocytosis.
Raised white blood cell count
Define thrombocythaemia.
Raised platelet levels.
Define leukaemia.
Neoplastic proliferation of white cells, usually disseminated throughout the blood.
Define Lymphoma.
Neoplastic proliferation of white blood cells, SOLID tumor.
Describe the indications for blood transfusion? (In what two situations are blood transfusions given)
Where 1 or more components of the blood have to be replaced quickly (from a great loss.)
When bone marrow cannot produce blood cells.
i.e. in leukaemia - bone marrow overproducing WBC and not producing RBC or platelets etc.
Name the 2 blood antigen systems.
ABO
D (rhesus)
What is the safest way a blood transfusion can be given?
Blood given by yourself.
The donor blood is taken weeks in advance of when the blood is required. Gives the patients blood time to recover before the operation/transfusion.
What blood type is universally given?
Group O
What blood group can recieve any blood?
Group AB
List the complications of blood transfusions.
Incompatible blood:
leads to lysis of RBC = jaundice, fever and death.
The cells burst and release the contents into circulation.
Fluid overload:
Going from a low volume of blood to a high volume can over work the heart.
Dangerous in those with cardiovascular problems, the old and the young.
Transmission of infection:
Blood borne viruses, prion disease (causes brain damage) and bacterial infections.
What PROTEINS regulate clotting/haemostasis?
Protein C and S
Describe the 3 components of haemostatic disorders.
Vascular component - associated with collagen disorders
Cellular component - platelet no. and function
Coagulation component - ability to balance clotting and break down of clots.
Availability of clotting factors.
What is involved in the cellular component of haemostatic disorders.
platelet number and function.
What assumption is made in terms of the cellular component? (Haemostatic disorders)
Adequate number of cells = adequate function
What have an effect on the cellular component?
NSAIDs and Asprin.
Permanent effect on platelets, takes 7-10 days for regeneration.
What is involved in the coagulation component of haemostatic disorders.
Is there adequate amounts of clotting factors being made and used. BALANCE
Is there adequate amounts of clotting and adequate amounts of clot lysis. BALANCE
What is coagulation regulated by?
The chemicals released by the blood vessels
In a clinical sitation how do you approach diagnosis of a haemostatic disorder?
Take a history - attention made to prolonged bleeding after extractions and minor cuts.
Visual cues: (Blotches on skin from bruising underneath)
Purpura
ecchymosis
Petechiae
What investigations can you carry out to determine haemostatic disorders?
Most common/useful:
Full blood count - count platelet numbers.
INR and APPT - How well the clots are produced
Bleeding time - determines platelet funtion.
LFT (clotting factor synthesisi)
What is haemophilia? What are the types of haemophilia?
Tendency to excessively bleed.
Range of severity
Haemophilia A - inherited deficiency of factor 8 (clotting factor)
Christmas disease/Haemophilia B - inherited deficiency of factor 9 (clotting factor)
Von Willebrand’s disease - Inherited deficiency of factor 8 paired with a lack of VW protein on platelets.
WHo is affected by haemophilia?
Males (females are carrers)
What is thrombophilia?
Tendency to clot.
What factors increase the risk of thrombophilia?
Smoking
Immobility; Travel and surgery associated
Trauma: Body goes into exaggerated clotting.
Medication: the pill
Pregnancy
List anti platelet drugs (old and new) what is their action?
Prevent platelet aggregation - leads to clot formation.
Aspirin
Clopidogrel
New:
Prasugrel
List anticoagulant drug (old and new) what is their action?
Prevents clots from forming and growing
Warfarin
New:
Rivaboxaban
Apixaban
What is porphyria?
VERY DANGEROUS - most individuals are unaware
Abnormality of haem metabolism.
What are the 2 main groups of porphyria?
Hepatic prophrias
Erythropoietic porphyrias
What are the clinical effects of porphyria?
Photosensitive rash Neuropsychiatric disturbances: Motory/sensory changes, seizures. Hypertension Tachycardia Death
What are the triggers of porphyria?
Medications: LOCAL ANAESTHETIC Pregnancy Acute infections Alcohol Fasting
What will many dental patients confuse an episode of porphyria with?
An allergy to local anaesthetic.
What could multiple reductions in blood cells indicate?
Bone marrow failure.
What could multiple increases in blood cells indicate?
Pre-neoplastic myelodysplasia which can lead to leukaemia.
Describe the process of blood transfusion.
Blood taken from patient
Tested against blood types; ABO and rhesus
Tested against the donor sample
Matched blood is given to the patient
In terms of haemostasis; what occurs in trauma?
Chemicals are released by cells that enhance/speed up clotting
What are the visual signs of clotting disorders?
Petechiae - Bleeding under the skin
Ecchymosis - bruising from blood under the skin
Purpura - prurple blotches on the skin/mucous membrane.
What are anti platelet drugs used in?
Treating atherosclerosis
What are anticoagulant drugs used in?
Treating thrombphilia
