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Diagnosis |
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Side Effects of Treatment |
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Catheters |
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Surgery |
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Radiotherapy |
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Blood Counts and Transfusions |
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Scans |
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Bone Marrow Transplants |
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Finishing the Treatment |
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Relapse |
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Blood, Blood Counts and Blood Product Transfusions
Blood comprises of a number of different cells suspended in a fluid called plasma. Blood cells are produced by the bone marrow which is the soft, spongy centre found inside most bones. As these cells wear out, they are filtered back from the blood stream and are continually replaced.
The major functions of blood include:
- To supply nutrients and oxygen to all parts of the body (red cells).
- To remove waste products and carbon dioxide from the body's cells, to organs where they can be excreted (red cells).
- To provide defence against infection by destroying bacteria and mounting immune responses (white cells).
- To prevent bruising and bleeding by assisting in the formation of clots (platelets).
There are three main types of blood cells:
Red blood cells are responsible for carrying oxygen from the lungs to all parts of the body. These cells are bright red in colour and usually last for about 120 days in the circulation after release from the bone marrow. "Anaemia" is the term used when there is a lack of red blood cells. Symptoms of anaemia include pallor, fatigue, loss of energy, listlessness, lack of appetite, dizziness, breathlessness and a fast heart rate.
To measure the amount of red blood cells in the blood we determine the HAEMOGLOBIN (Hb) level. A normal Hb in childhood varies according to age but is usually between 10.0 and 14.0 grams per 100 ml of blood. A packed red cell transfusion may be given if the Hb is less than 8.0 grams/100 ml or if the child is symptomatic (eg. dizzy or breathless).
There are five different types of White Blood cells that circulate in the blood and their main function is in the prevention of infection. The normal white cell count in children varies considerably, but is usually between 3.5 to 15 x 109/litre.
The type of white blood cell most commonly talked about in paediatric oncology is the NEUTROPHIL (or granulocyte). Neutrophils destroy bacteria in the body and help prevent septicaemia (blood-poisoning). The neutrophil numbers are usually expressed as a percentage of the total white cell count and the absolute neutrophil count can be calculated. In children who are having chemotherapy an absolute neutrophil count of 1 x 109/litre (which is the same as 1000 per cubic millilitre) is considered to provide adequate protection against infection. If the neutrophil count falls below 500 neutrophils per cu.mm. (ie < 0.5 x 109/litre) the risk of bacterial infection is increased and the child should be watched for signs of infection. If a child with a low neutrophil count develops a fever or becomes sick in any way then their doctor should be immediately notified because antibiotics may need to be given.
Although it is possible to transfusion white blood cells, this is not normally done as they have a very short life span and are not usually effective.
Lymphocytes are white cells that are responsible for fighting viruses and making antibodies. Acute Lymphoblastic Leukaemia is a cancer of the lymphocytes.
Platelets are small cells that are produced by the bone marrow and their function is to help in the formation of clots. If there are inadequate platelets the child is at risk of increased bleeding and bruising, and occasionally spontaneous bleeding can occur.
Bruising is most common on the limbs or trunk and sometimes, small red pin-head dots can appear. Oozing can also occur from the mouth and gums (especially if ulceration is present) or nose.
A normal platelet count is 150 to 500 x 109/litre. Platelet transfusions are usually given if the child has evidence of active bleeding or in some other special circumstances when the risk of bleeding is high.
Aspirin or medicines containing aspirin-like substances (eg. many cough and cold medicines) should not be given to patients having chemotherapy as aspirin interferes with the "stickiness" of platelets and can increase the risk of bleeding.
TRANSFUSIONS
There are many blood components that are available for transfusions but the products most commonly transfused in paediatric oncology are PACKED RED BLOOD CELLS (packed cells) and
PLATELETS. These products are collected and distributed by the Red Cross Transfusion Service. The Red Cross have strict guidelines for the screening of donors and all blood collected is tested for the group and Rh status, hepatitis B and C, HIV antibody, syphilis and any unusual antibodies.
Packed Cells are red blood cells that are prepared from whole blood by removing some of the plasma.
Platelet transfusion packs (bags) are prepared by separating out the platelets from whole blood. The platelet concentrate is suspended in a small amount of plasma and may contain some residual red cells and lymphocytes. The volume of platelets transfused depends on the size of the child and is usually between 4 to 8 bags. Platelets are transfused over about 30 minutes per bag. Reactions to platelets are quite common and include fever, chills, rash and hives. These are usually treated or prevented with an antihistamine and panadol.
Platelets and packed cells are sometimes given through a special filter which reduces the number of white cells in the transfusion and this can help reduce reactions and prevent some infections.
For patients undergoing bone marrow transplant, multiple units of platelets may be collected in one bag from an individual donor, by the use of a cell separator. Platelets and red cells for bone marrow transplant patients also must be IRRADIATED before they are given to the patient.
CHECKING THE BLOOD COUNT
Your doctor will check the blood count to determine the number of each of the above cells
at the time chemotherapy is due or if an infection is suspected. When the blood count is
low, chemotherapy may be delayed and antibiotics may be required if the child develops a
fever.
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