Blood Counts

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What is blood?

Blood is made up of three basic types of cells:

  • Red blood cells. The hemoglobin in the red blood cell carries oxygen to all parts of your body to give you energy. If your red blood cell count is low (anemia), you may look pale and feel tired. If your hemoglobin is very low, you may need a blood transfusion.
  • White blood cells. White blood cells fight infections. The white blood cells that fight the best are called neutrophils (segs). Your neutrophils are called "bands."
  • Platelets. Platelets help prevent bleeding by clotting the blood. These cells travel through your body in a white/yellow liquid called plasma. When your platelet count is low you may bleed when you get a cut, bruise or nose bleed. You may, if your count is very low, need a platelet transfusion to prevent bleeding.

Where do blood cells come from?

Your body is constantly producing blood cells. Blood cells are made in the bone marrow, the spongy tissue inside your bones. They come from a type of cell called a stem cell. The stem cell divides in response to signals made by your body. It will either become a red blood cell, a white blood cell, or a platelet. These signals are called growth factors. Blood cells live for a specified time in your body. White blood cells live for a few hours to a few months. Red blood cells live for 120 days. Platelets live for five to nine days.

Why does chemotherapy affect my blood cells?

Chemotherapy affects rapidly growing cells more than slower growing cells. Some normal cells have a fast rate of growth. These include your blood cells. A side effect of chemotherapy may destroy young blood cells as they are growing. It can take anywhere from seven to 21 days for your blood cells to reach their lowest numbers.

Your nurse or doctor will tell you when your blood cells counts are expected to be low. This is called your nadir. You will have your blood tested periodically to see how many of each type of blood cell you have. This is called having your counts checked.

What happens when my counts are low?

Red blood cells are measured by values called hemoglobin (Hgb) and hematocrit (Hct). The normal value for hemoglobin is 14.0 to 18.0; hematocrit is 37 to 52. If your red blood cell count is low, you may feel more tired or short of breath than usual. This is called anemia. Your doctor may order a red blood cell transfusion for you. Sometimes your red blood cells may be low because of the disease itself. Your doctor may prescribe a growth factor called erythropoietin (EPO) to help increase your red blood cell counts.

One type of white blood cells are neutrophils. When neutrophils are low, this is called neutropenia. You may not see the usual signs of infection so review the signs of infection at the bottom of this page.

A normal white blood cell count is 4,000 to 10,000. Sometimes your doctor may order a growth factor called GM-CSF or G-CSF to help your white blood cells recover more rapidly. The neutrophils fight most common infections. For that reason, this portion of the white cell count is also monitored. This is called the Absolute Neutrophil Count (ANC).

A normal platelet count is 130,000 to 400,000. A platelet count below 50,000 may make you more at risk for bleeding. This is called thrombocytopenia. If your platelet count drops, your doctor may order a platelet transfusion for you.

What should I do if my counts are low?

Talk with your nurse or physician about avoiding crowds and public places such as shopping malls, airplanes, buses, trains, etc. You may need to wear a mask if your white blood count is very low.

Good hygiene is important. Shower or bathe daily and pat yourself dry. Wash hands often and well. Always wash them before eating and after using the bathroom.

  • Try to avoid nicks, cuts, and tears in your skin.
  • If you nick, cut or burn yourself, wash skin immediately with soap and water Bandage the cut if necessary.
  • Avoid going barefoot.
  • Wear gloves when doing any physical activity that might dry or damage your skin.
  • Be careful cutting or trimming your nails to avoid small nicks.
  • Do not have a manicure.
  • Use cuticle cream remover instead of picking, tearing or cutting cuticles.
  • If you shave, use an electric razor.
  • Do not take rectal temperature.
  • Do not clean out litter boxes or bird cages. Avoid all contact with animal urine or stool.
  • Avoid long exposure to the sun. Wear sunscreen of at least SPF 30.
  • Avoid getting a sunburn.
  • Brush your teeth two to four times per day with a soft toothbrush and rinse with a mixture of salt and water or baking soda and water. Good mouth care will help decrease the number of germs in your mouth.
  • Prevent constipation. Straining to have a stool could cause small tears in the rectal area.
  • Do not use suppositories or enemas unless told otherwise by your nurse or doctor.
  • If needed your physician can recommend a stool softener.
  • Wipe very gently but thoroughly after a bowel movement.
  • Tears in the lining of the intestine or rectal area can be dangerous when the white blood cell count is low.
  • Increase your dietary fiber with fruits and vegetables.
  • Drink eight 10-ounce glasses of liquid a day.
  • Perform gentle exercise such as walking daily.
  • Take short rest periods between activities.
  • If you receive blood or platelets at a hospital other than Dana-Farber, make sure they are irradiated or leukoreduced. Obtain a medical alert bracelet.
  • Do not take medications containing aspirin or ibuprofen unless your doctor tells you to. These drugs can make the platelets less effective.
  • If your platelet count is low:
    • you should not have sexual intercourse.
    • women should not use tampons or douche.
    • You should avoid trauma during sexual relations, maintain cleanliness and lubrication.

Signs of Infection

Be sure to notify your nurse or doctor immediately if you have any abnormal bleeding. This includes nose bleeds, blood in urine or stool, dark tarry stools, bleeding gums or easy bruising.

Be sure to let your nurse or doctor know if you develop any of the following signs of an infection:

  • a fever of 100.5 degrees or more
  • loose stool for more than two days
  • severe night sweats, shaking chills
  • shortness of breath, cough or sore throat
  • headaches or neck stiffness
  • frequent urination, burning with urination
  • redness, swelling, pain or discharge from anywhere on your body
  • extreme fatigue