Haemotology Flashcards
Coagulation cascade:
- Prothrombin to thrombin
- Thrombin changes fibrinogen to fibrin
- Causes the cross-linked fibrin coat
Two pathways of the coagulation cascade:
- Intrinsic: important for amplification more than initiation
- extrinsic: important for initiation, triggered by release of tissue factor from damaged tissue
4 components of clotting:
- Vascular response - vasoconstriction
- Platelet plug formation
- Fibrin plug - intrinsic and extrinsic pathway
- Lysis of clot
Objective assessment:
- Lymph node assessment
- Palpate liver and spleen
- Skin
- Eyes, mouth
- Neurological
- Vital signs
Full Blood Count components:
- Haemoglobin
- Haematocrit (packed cells)
- White cell count
- Erythrocyte sedimentation rate
- Platelets
- Other: blood typing, Rh factor, iron metabolism
Cause of low Hb:
- inadequate production of RBC
- inadequate iron intake
- inadequate folate/vitamin B12
- microscopic bleeding/blood loss
- blood cell destruction
- chronic illness
- defect in Hb molecule
Haematocrit:
- percentage of packed RBC in a whole blood sample
- influenced by absolute number of cells, but also average size of cells
erythrocyte sedimentation rate:
- time needed for the RBCs in a whole blood sample to settle to the bottom
International Normalised Ratio (INR)
- measure of how long it takes for blood to clot
- target INR different for different conditions (eg. AF 2-3seconds)
- higher INR recommended for mechanical heart valve or irregular clotting conditions.
Diagnostics:
- Full Blood Count
- Coagulation panel (PT, INR, APTT)
- Liver function tests
- Platelet count
- ESR
- Fibrinogen
- Iron studies
- Stool for hemoccult blood
Low Molecular Weight Heparin (LMWH)
- 100-750 times smaller than heparin
- greater SC availability and longer half-life
- fewer adverse effects
- eg. Clexane (enoxaparin)
Prophylactic vs analgesic aspirin doses:
- Prophylactic (platelet coagulation): 100-150mg
- Analgesic/anti-inflammatory effect: 300-600mg
Lymphoma
Malignancy of lymphocytes that begins in lymph nodes.
- Hodgkins (more common in young and male)
- Non-Hodgkins (90% of lymphomas, B cell (CLL & SLL)
Lymphoma risk factors:
- Radiation exposure
- Weakened immune system (immunosuppressants, genetics)
- more common in people with autoimmune diseases
- caused by infection (eg. helicobacter pylori, HTLV-1)
- exposure to chemicals/drugs (eg. benzene, herbicides, insecticides)
- chemotherapy
Diagnosis of lymphoma:
- symptoms (eg. fatigue, infection, lymph node enlargement
- biopsy
- blood smear - morphology
- blood counts
- immunophenotypic markers
Lymphoma treatment:
- Chemo/radiotherapy
- monoclonal antibodies
- stem cell transplant
Role of WBC
- fighting pathogens/infection
- clearing debris
- healing tissue
Role of RBC
- transportation of oxygen and CO2 between pulmonary and systemic circulation
- risk of anaemia if lacking
Role of platelets
- clotting
- intrinsic clotting cascade
- risk of bleeding if lacking
Nursing considerations when bone marrow is suppressed by disease or treatment?
- reduced platelets –> do not give anticoagulants, antiplatelets or thrombolytics
- reduced WBC –> do not give immunosuppressants
- reduced RBC –> may need iron transfusions and regular haemoglobin level testing
Causes of iron deficiency anaemia:
- Diet = inadequate diet intake
- Blood loss due to menstruation = IUDs can cause increased blood loss
- Pregnancy = mother and baby require a lot of iron for extra RBCs so more iron is needed in pregnancy
Iron deficiency anaemia treatments:
- iron infusion
- iron supplements
Universal donor:
- O blood type
- no antigens present on cell, therefore no antibodies can destroy them, anyone can take them
Universal recipient:
- AB blood type has no antibodies against antigens, therefore can take any blood type
