Haematological Disorders. Flashcards
The composition of Blood:
Write the Percentage or Portion of total blood or Total volume, as appropriate.
Total blood volume Plasma White blood cells Red blood cells Water
Total blood volume: 10% Plasma: 55% White blood cells: 1% Red blood cells: 45% Water: 90%
Describe the difference between oncotic pressure and hydrostatic pressure?
Essentially, hydrostatic pressure pushes out while osmotic pressure pulls in.
In the capillaries, hydrostatic pressure increases filtration by pushing fluid and solute OUT of the capillaries.
While capillary oncotic pressure (also known as colloid osmotic pressure) pulls fluid into the capillaries and/or prevents fluid from leaving.
Hydrostatic pressure is based on the pressure exerted by the blood pushing against the walls of the capillaries.
Oncotic pressure exists because of the proteins - like albumin, globulins and fibrinogen - that do not leave the capillary and draw water.
What might low albumen levels indicate?
- Albumin is a protein that is found in the blood. Poor nutritional state. You may have some form of liver disease, such as hepatitis, or cancer in your liver, which may have spread from elsewhere in your body that causes you to lose albumin, thus resulting in hypoalbuminemia.
- Certain heart conditions - such as congestive heart failure, or pericarditis - may cause you to have low albumin levels in your blood
Identify three types of granulocytes and their function.
Neutrophils
Phagocytes in early inflammation
Eosinophils
Eosinophils ingest antigen-antibody complexes
Induced by IgE hypersensitivity
Attack parasites
Basophils
Structurally and functionally similar to mast cells
Cytoplasmic granules contain vasoactive amines
Histamine
What is haemoglobin and how it is produced?
Haemoglobin is the protein inside red blood cells that carries oxygen and it is produced in the stem cells bone marrow.
Discuss how iron balance is maintained within the body.
Iron balance is maintained through controlled absorption at the intestines. Regulation of iron transport across the plasma membrane of GI epithelial cell is related to the cells iron content and the overall rate of erythropoiesis.
What is the impact on the body if the iron intake and maintenance does not meet or exceeds functional requirements?
If the body’s iron stores are low or the demand of erythropoiesis increases, iron is transported rapidly through the intestinal epithelial cell and into the plasma.
Identify three haematological changes that occur with the ageing process.
Blood vessels lose their compliance, may cause high BP
Incorporation of iron in marrow culture from older people is comparable to that from younger people, but it increases less with erythropoietin stimulation.
Although iron uptake from the intestines is normal in the elderly, slowed erythropoiesis reduces incorporation of iron into RBCs.
Define the term Pernicious anaemia and identify two complications that may occur if left untreated.
Pernicious anaemia is defined as a type of vitamin B12 deficiency that results from the impaired uptake of vitamin B-12 due to the lack of a substance known as an intrinsic factor (IF) produced by the stomach lining.
Pernicious anaemia can cause permanent damage to nerves and other organs if it goes on for a long time without being treated. It also raises the risk of developing stomach cancer.
Discuss how a patient may present if suffering from sickle cell anaemia.
Fatigue Weakness Dyspnoea Pallor Tachycardia Tachypnoea
How does this differ to a patient in sickle cell crisis?
It affects the production of RBC, causing occluded circulation, impaired erythropoiesis, or sequestration of large amounts of blood in the liver or spleen.
Identify 5 long-term complications associated with sickle cell anaemia?
Stroke.
A stroke can occur if sickle cells block blood flow to an area of your brain. Signs of stroke include seizures, weakness or numbness in your arms and legs, sudden speech difficulties, and loss of consciousness. If your baby or child has any of these signs and symptoms, seek medical treatment immediately. A stroke can be fatal.
Acute chest syndrome.
This life-threatening complication causes chest pain, fever and difficulty breathing. Acute chest syndrome can be caused by a lung infection or by sickle cells blocking blood vessels in your lungs. It might require emergency medical treatment with antibiotics and other treatments.
Pulmonary hypertension.
People with sickle cell anaemia can develop high blood pressure in their lungs (pulmonary hypertension). This complication usually affects adults rather than children. Shortness of breath and fatigue are common symptoms of this condition, which can be fatal.
Organ damage.
Sickle cells that block blood flow through blood vessels immediately deprive the affected organ of blood and oxygen. In sickle cell anaemia, blood is also chronically low on oxygen. Chronic deprivation of oxygen-rich blood can damage nerves and organs in your body, including your kidneys, liver and spleen. Organ damage can be fatal.
Blindness.
Sickle cells can block tiny blood vessels that supply your eyes. Over time, this can damage the portion of the eye that processes visual images (retina) and lead to blindness.
Identify the 6 classifications of anaemia.
- Iron deficiency anaemia
- Thalassemia
- Aplastic anaemia
- Haemolytic anaemia
- Sickle cell anaemia
- Pernicious anaemia
- Fanconi anaemia
Discuss the pathophysiological mechanisms of anaemia.
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Which blood tests are performed to diagnose and evaluate anaemia?
Full blood count (FBC) is done to determine blood cell
counts, haemoglobin, haematocrit and red blood cell indices.
Iron levels and total iron-binding capacity are performed to detect iron deficiency anaemia.
Serum ferritin is low due to depletion of the total iron reserves available for haemoglobin synthesis.
Sickle cell test is a screening test to evaluate haemolytic anaemia and detect HbS.
Haemoglobin electrophoresis separates normal haemoglobin from abnormal forms.
