Disorders of the blood Flashcards
1
Q
What are the main functions of the blood? (4 points)
A
- Ability to transport nutrients
- Ability to carry and remove waste
- Ability to transport host depences
- Ability to self repair
2
Q
What makes up the blood? (5 points)
A
- Cell component
- Plasma proteins (albumin, globulin)
- Lipids
- Nutrients
- Water
3
Q
Is it easy to make artificial blood?
A
No, as a lot of things make up normal blood and it is tricky to include all of these things into artificial blood
4
Q
What does ‘FBC’ stand for?
A
- Full blood count
5
Q
What does ‘CBC’ stand for (used in America)?
A
- Complete blood count
6
Q
What does ‘RBC’ stand for?
A
- Red blood cells
7
Q
What does ‘RCC’ stand for?
A
- Red cell count
8
Q
What does ‘WCC’ stand for?
A
- White cell count
9
Q
What does ‘PLT’ stand for?
A
- Platelets
10
Q
What does ‘HCT’ stand for?
A
Haematocrit
11
Q
What is haematocrit?
A
- What proportion of the blood volume is cells and what proportion is liquid
12
Q
What does ‘MCV’ mean?
A
- Mean cell volume
13
Q
What is anaemia?
A
- Low haemoglobin levels
- Can have loads of RBC’s with little Hb which causes anaemia or can have few RBC’s with loads of Hb so no anaemia
14
Q
What is Leukopenia?
A
- Low White blood cell count
15
Q
What is thrombocytopenia?
A
- Low platelets
16
Q
What is Pancytopenia?
A
- All cells reduced (low in number)
- Will generally mean that bone marrow is not working as this is where the cells are produced
17
Q
What happens if someone has 1 blood cell deficiency?
A
- Reactive change to the invironment
18
Q
What has happened if someone has multiple blood cell deficiencies?
A
- Bone marrow failure
19
Q
What is polycythaemia?
A
- Raised Hb (opposite to anaemia)
20
Q
What is leucocytosis?
A
Raised White blood cell count
21
Q
What is thrombocythemia?
A
Raised platelets
22
Q
What happens if there is one blood cell that is being over produced?
A
Reactive or pre-neoplastic
23
Q
What is it called when multiple blood cell levels are raised?
A
- Pre-neoplastic (myelodysplasia)
24
Q
What is Leukaemia?
A
- Neoplastic proliferation of white cell
- usually disseminated (spread through the blood)
25
What is Lymphoma?
- Neoplastic proliferation of white cells
| - BUT not in the circulation, usually a solid tumour
26
Blood transfusions can be given where one or more components of the blood have to be replaced quickly. Give examples of these components? (3 points)
- Red cells
- Platelets
- Clotting factors
27
Blood transfusions can be given where the bone marrow cannot produce blood cells. Give 2 examples of these blood cells?
- Red cells
| - Platelets
28
What are the types of antigens in the blood (2 points)
ABO system
- A
- B
- O
- AB
D system (rhesus)
= + or -
29
What 2 things indicate that a blood transfusion is needed?
- Blood loss
- Specific production problems
(RBC, platelets, plasma proteins - clotting factors, albumin, gamma globulins)
30
Why in general should you AVOID giving a blood transfusion if at all possible?
- Because we don't always know what else is in the blood
31
What is the 1 completely safe way of getting a blood transfusion?
- By giving yourself a blood transfusion
- If getting for example a hip replacement done - patient usually looses about 2 units of Hb - if the paitnet knew they were getting this operation on 8-12 weeks can take blood from the patient before this and it can be stored so when the patient has the operation you can take their blood and transfuse it back into them
32
What is the process of giving a blood transfusion?
- Sample taken from patient
- Tested against known blood types
- Tested against donated sample
- Matched blood given to patient
33
What is the first stage in the process of giving a blood transfusion?
Sample taken from the patient - need to find out about their blood
34
What is the second stage in the process of giving a blood transfusion? (3 points)
Tested against known blood types:
- Basic ABO compatibility
- Rhesus compatibility
- Does not always detect irregular antibodies
35
What is the third stage in the process of giving a blood transfusion?
- Blood from patient tested against donated sample
- If donated sample and patients sample when put together don't do anything bad then it should be safe to give them the transfusion
36
What is the fourth stage in the process of giving a blood transfusion?
- Matched blood is given to the patient
37
What blood group is a universal donor?
- O
38
What are 3 possible blood transfusion complications?
- Incompatable blood
- Fluid overload
- Transmission of infection
39
Incompatible blood is a possible blood transfusion complication. What can this lead to? (4 things)
- RBC lysis
| - Fever, jaundice, death
40
Fluid overload can be a blood transfusion complication. What can this lead to?
- Heart failure
- If a patient is healthy and is not lacking volume but only the extra cells then extra fluid may make any possible heart condition worse
41
Transmission of infection is a possible blood transfusion complication. What can this lead to? (3 points)
Blood borne viruses
- CMV, Hep B, Hep C, HIV, TT virus
Prion disease
- vCJD
Bacterial Infections
- Syphilis
42
What is haemostasis?
- The stopping of a blood flow
43
When does the clotting cascade work?
- continuous process that happens all the time - the rate at which it happens is what changes
44
What does fibrinolysis in the clotting cascade break down?
- The fibrin inhibitor
45
What are the three different categories of haemostatic disorders?
- Vascular component
- Cellular component
- Coagulation component
46
What does a haemostatic disorder of the vascular component cause?
- Retraction of vessel (collagen disorder)
| - People who make abnormal collagen means the blood vessels will not act as they should
47
What does a haemostatic disorder of the cellular component cause?
- Changes in platelets number and function
48
What does a haemostatic disorder of the coagulation component cause? (2 points)
- Prevents adequate clotting
| - Prevents clot lysis
49
To check that platelet function is okay you can heck the 'bleeding time' of a patient. What is this?
- Cut someone and see how long it takes for them to stop bleeding
- If have the right number of platelets generally the platelet function will be normal
- Assume the function is okay unless have a huge number of platelets
50
Aspirin and NSAID's will have a permanent effect on platelets. How long before new platelets are formed?
- 7-10 days
51
For the coagulation component of haemostatic disorders what do you need an adequate amount of clotting factors and an adequate range of clotting factors. What causes an inadequate range of clotting factors?
A hereditary deficiency - Factors V, VIII, IX and XI
52
To prevent a haemostatic disorder in the coagulation component, what do you need a proper balance between?
- Thrombotic and thrombolytic systems
- If you can make lots of clot but cannot break down again then you have a lot of solid fibrin in your blood vessles - important
- If clots don't break down adequately then will get clots where they shouldn't be
53
Why do people with haemophilia suffer to varying degrees?
- Women tend not to get haemophilia as it is an X-liked clotting factor so if women has 1 abnormal X chromosome then they will still make 50% of the normal clotting factor
- Whereas if men, have one Y and one abnormal X chromosome then they may only make 5%. 10% or any variety of % of normal clotting factor
54
In a clinical situation when should yo ask if a patient has a history of prolonged bleeding?
- After extractions
| - After minor cuts
55
In a clinical situation what should you look for visual signs of is a patient has a haemostatic disorder? (3 points)
- Purpura
- Ecchymosis
- Petechiae
56
What is purpura?
- A rash of purple spots on the skin caused by internal bleeding from small blood vessels
57
What is ecchymosis?
- A discolouration of the skin resulting from bleeding underneath, typically caused by bruising
58
What is petechiae?
- A small red or purple spot caused by bleeding into the skin
59
What are the possible investigations you can take to test for haemostatic disorders?
- FBC (platelet numbers)
- Bleeding time (platelet function)
- INR (how easily you can produce a clot) and APPT
- LFT (clotting factor synthesis)
60
What does LFT stand for?
- Liver function test
61
What is haemophilia a inherited deficiency of?
- VIII or IX
62
What effect does haemophilia have on a patient?
- Varying effecr - mild, moderate, severe
| - MALES are affected, FEMALES are carriers
63
What diseases can haemophilia lead to due to blood transfusions? (3 points)
- HBV, HCV, HIV
64
Thrombophilia is an excessive tendency to clot. Why is this life threatening?
- Can cause a pulmonary embolism
65
Thrombophilia is a genetic condition but can be exacerbated by thrombo-promoting actions. What are 5 examples of these?
- Smoking
- Immobility - travel
- Surgery
- Pregnancy
- Medicines - oestrogen contraceptive pill
66
What is therapeutic coagulopathy?
- Where the coagulation system is manipulated by medicine to make clotting less likely
67
What does therapeutic coagulopathy do? (2 points)
Reduces the platelet adhesion and function
- Usually prevent arterial thrombosis
Reduce activity in the coagulation cascade
- Usially prevent venous thrombosis
68
What are 3 examples of standard antiplatelet drugs?
- Aspirin
- Dipyrimadole
- Clopidogrel
69
What are 2 examples of new antiplatelet drugs?
- Prasugrel
| - Ticagrelor
70
W hat is an example of a standard anticoagulant drug?
- Warfarin
71
What are 3 examples of new anticoagulant drugs?
- Apixaban
- Dabigatran
- Rivaroxaban
72
What should you always do in a dental respect in relation to haemostatic disorders before treating a patient? (3 points)
- ALWAYS ask about bleeding
- ALWAYS look for bleeding problems
= Skin - red spots or purpura
= Mucosa - purpura or blood blisters
- If in doubt TEST first
= FBC, INR, APPT
73
If you, as a dentist, know the patient has a haemostatic problem, what should you do? (3 points)
- Ask ADVICE from a dental specialist
- Follow available SDCEP guidance for dental care delivery
- REMEMBER local haemostatic measures
74
What do you need to know about Porphyria?
- It is BAD
75
What is Porphyria?
- A group of rare genetic disorders. Called porphyria's because they cause a build up of chemicals called porphyrins or the simpler chemicals used by the body to make porphyrins
- It is an ABNORMALITY in haem metabolism
76
How much of the population has porphyria?
- 1 : 10,000
77
What are the 2 main groups of porphyria?
- Hepatic porphyrias
| - Erythropoietic porphyria's
78
What is a big problem with people who have porphyria?
- They dont know they have it until they have an acute episode
79
What are 3 clinically relevant porphyria's?
Variegate
- Afrikaans decent
Acute intermittent
- Any population group
Hereditary coproporphyria
80
What are the possible clinical effects of a patient who has porphyria? (4 points)
- Photosensitive rash
- Neuropsychiatric disturbance in acute attacks
(motor and sensory changes, seizures and autonomic disturbances)
- Hypertension and tachycardia
- May be fatal
81
What are 5 possible triggers of porphyria?
Poorly understood
- Many drugs (important from dental point of view - especially LA)
- Pregnancy
- Acute infections
- Alcohol
- Fasting
82
What is CMV?
- Cytomegalovirus
83
What is the prion disease - vCJD?
- Varient Creutzfeldt- Jakob disease
84
What blood tests could you ask for to test someone's coagulation? (3 points)
- Ask for FBC
- Platelet Test
- Bleeding time
85
How does aspirin inhibit the formation of blood clots?
- By preventing platelets from producing a chemical called thromboxane A-2, Which normally induces platelet clumping
- Without thromboxane A-2, platelets cannot stick together and join with fibrin to make blood clot
86
What is the INR test (international normalised ratio)? (2 points)
- A measure of the patients prothrombin time based on what it would be if measured using the WHO international reference reagent. The INR is used as a standard for monitoring the effects of anticoagulant treatment with WARFARIN.
- The blood test looks to see how well your blood clots
87
What should a persons INR be if they are taking a blood thinner?
- Between 2 and 3
88
What is a pulmonary embolism?
- When a blood clot gets caught in the arteries in the lungs
89
What is an APPT test?
- Activates Partial Thromboplastin Time test
90
What are 2 examples of local haemostatic measures?
- Pack socket with haemostatic material that will produce a meshwork to control the clot
- Cover with stitches to close the wound
