Disorders of the blood Flashcards
1
Q
What are the functions of the blood
A
- transport of nutrients
- removal of waste
- transport host defences
- ability to carry nutrients/waste/defences
- ability to self repair
2
Q
what are the components of blood
A
- cell component
- plasma proteins (albumin, globulin)
- lipids
- nutrients
- water
3
Q
What is FBC
A
full blood count
will measure all the cells in the blood
4
Q
What is RBC
A
red blood cells
5
Q
What is RCC
A
red cell count
6
Q
What is WCC
A
white cell count
7
Q
What is PLT
A
platelets
8
Q
What is HCT
A
hematocrit
9
Q
What is MCV
A
mean cell volume
10
Q
What is the hematocrit
A
what is the proportional value that is cell and liquid
usually ~0.4-0.5
if high = viscous/clotting problems
11
Q
Define anaemia
A
low Hb
12
Q
Define leukopenia
A
low WCC
13
Q
Define thrombocytopenia
A
low platelets
14
Q
Define pancytopenia
A
all cells reduced
15
Q
If you have one of anaemia/ leukopenia/thrombocytopenia or pancytopenia what might this indicate
A
reactive change to environment
16
Q
If you have multiple of anaemia/ leukopenia/thrombocytopenia or pancytopenia what might this indicate
A
bone marrow failure
17
Q
Define polycythaemia
A
raised Hb
18
Q
Define leukocytosis
A
raised WCC
19
Q
Define thrombocythaemia
A
raised platelets
20
Q
If you have one of polycythaemia/ leukocytosis/ thrombocythaemia what might this indicate
A
reactive or pre-neoplastic
21
Q
If you have multiple of polycythaemia/ leukocytosis/ thrombocythaemia what might this indicate
A
pre-neoplastic (myelodysplasia)
22
Q
Define leukaemia
A
neoplastic proliferation of white cells, usually disseminated
23
Q
Define lymphoma
A
neoplastic proliferation of white cells, usually a solid tumour
24
Q
Why might someone have to get a blood transfusion?
A
- where one or more components of the blood has to be replace quickly (RBCs, platelets, clotting factors)
- where the bone marrow cannot produce blood cells (red cells, platelets)
25
What are the blood antigens
```
ABO system (A,B,O,AB)
D system (rhesus, + ro -)
```
n.b. there are others too
26
Why if possible should we avoid blood transfusions
we don't always know what is in the blood e.g. HepC didn't used to test for as didn't know it existed
27
What is a safe way to have a blood transfusion
giving yourself one
e.g. a hip operation
(if you know in advance you can store blood from the patient, patient replaces blood before the operation)
28
What is the process of a blood transfusion
- sample taken from patient
- tested against known blood types
(ABO and rhesus compatability)
- tested against donated sample
- matched blood given to patient
29
what antibodies does group AB have
none
30
What antigens does group B have
B
31
what antibodies does group O have
Anti A and B
32
what antibodies does group A have
Anti -B
33
what antigens does group O have
none
34
what antigens does group AB have
A and B
35
what antibodies does group B have
Anti -A
36
what is cross matching
when you mix blood from groups with different antibodies to see if they react
37
what happens when blood reacts with the antibodies it is cross matched with
coagulation
38
What are some possible transfusion complications
- incompatible blood (RBC lysis)
- fluid overload (Heart failure)
- transmission of infection (blood borne viruses, prions, bacterial infections)
39
As dentists what do we need to know about haemostatic disorders
- that coagulation is a continuous process
- understand principles of investigating a patient with a bleeding disorder
- know what investigations to ask for
40
What are the 3 components that can be abnormal in someone with a haemostatic disorder
- vascular component (retraction of vessel-collagen disorder)
- cellular component (platelets number and function)
- coagulation component (adequate clotting, adequate lysis)
41
How does aspirin/ NSAIDs affect platelets
reduces clotting ability for the lifetime of platelets present when dose taken (7-10 days)
42
what can be abnormal about the coagulation component of blood
- amount of clotting factors
- range of clotting factors
- balance between thrombotic and thrombolytic systems
(X linked condition)
43
What happens in disseminated intravascular coagulation (DIC)
a condition in which small blood clots develop throughout the bloodstream, blocking small blood vessels. The increased clotting depletes the platelets and clotting factors needed to control bleeding, causing excessive bleeding.
44
What clinical signs might someone with a clotting disorder present with
history of prolonged bleeding
- after extractions
- after minor cuts
visual signs
- pupura (purple blotches on skin)
- ecchymosis
- petechniae
45
What investigations can you do on someone with a suspected clotting disorder
- FBC (platelet numbers)
- Bleeding time (platelet function)
- INR and APPT
- LFT (clotting factor synthesis
(FBC and INR are main ones)
46
What does an INR test
how well you can produce a clot, testing how well the system works and can you make clotting factors, do they have enough clotting factors
1 = normal
the higher the number the thinner the blood
47
Characteristics of haemophilia?
- inherited deficiency of VIII or IX
- males affected, females carriers
- can be mild, moderate, severe
- treatment led to HBV, HCV and HIV (now treated using e.coli with genetic enginerring to make more factor VIII)
48
What is thrombophilia
excessive tendency to clot - usually DVT
49
what can exacerbate thrombophilia
```
smoking
immobiliity
surgery
pregnancy
medicines (OCP)
```
50
what is therapeutic coagulopathy
where the coagulation system is manipulated by medicine to make clotting less likely
51
how is therapeutic coagulopathy achieved
reduce platelet adhesion and function
(usuallly prevent arterial thrombosis)
reduce activity in the coagulation cascade (usually prevent venous thrombosis)
52
where do I look if i have a patient with a bleeding disorder
SDCEP (anticoagulant/antiplatelet)
53
What is the standard anticoagulant drug
warfarin
54
what drugs are coming to replace warfarin
- apixaban
- dabigatran
- rivaroxaban
55
As a dentist what's important to think/ do about bleeding problems
- always ask about bleeding problems
- always look for bleeding problems
- if in doubt test first (INR)
- if known haemostatic problem ask advice
- follow avaliable SDCEP guidance for dental care delivery
- remember local haemostatic measures
56
what do i need to know about porphyria
that it's bad
(abnormality or haem metabolism, 1:10000 population, 2 main groups, most people don't know they have them until they have an acute episode)
(photosensitive rash, neuropsychiatric disturbance in acute attacks, hypertension and tachycardia, may be fatal)
triggers are poorly understood (drugs including LA, pregnancy, acute infections, alcohol, fasting)
