What is the hematocrit?
The hematocrit is the proportion, by volume, of the blood that consists of red blood cells. The hematocrit (hct) is expressed as a percentage. For example, a hematocrit of 25% means that there are 25 milliliters of red blood cells in 100 milliliters of blood.
How is the hematocrit measured?
The hematocrit is typically measured from a blood sample by an automated machine that makes several other measurements of the blood at the same time. Most of these machines in fact do not directly measure the hematocrit, but instead, calculate it based on the determination of the amount of hemoglobin and the average volume of the red blood cells.
The hematocrit can also be determined by a manual method using a centrifuge. When a tube of blood is centrifuged, the red cells will be packed into the bottom of the tube. The proportion of red cells to the total blood volume can then be visually measured.
What is a normal hematocrit ranges by ages?
The normal ranges for hematocrit are depended on the age after adolescence and the sex of the individual. The normal hematocrit ranges by age chart are shown here:
| Age | Hematocrit Ranges |
|---|---|
| Newborn | 55% - 66% |
| One (1) week of age | 47% to 65% |
| One (1) month of age | 37% to 49% |
| Three (3) months of age | 30% to 36% |
| One (1) year of age | 29% to 41% |
| Ten (10) years of age | 36% to 40% |
| Adult males | 42% to 54% |
| Adult women | 38% to 46% |
These values may vary slightly among different laboratories.
QUESTION
Sickle cell disease is named after a farming tool. See AnswerWhat does a low hematocrit mean?
A person who has a low hematocrit is referred to as being anemic. There are many reasons for anemia. Some of the more common reasons are
- loss of blood (traumatic injury, surgery, bleeding, and colon cancer),
- nutritional deficiency (iron, vitamin B12, folate),
- bone marrow problems (replacement of bone marrow by cancer,
- suppression by chemotherapy drugs, kidney failure), and
- abnormal hemoglobin (sickle cell anemia).
What does a high hematocrit mean?
Higher than normal hematocrit levels represent abnormally elevated red blood cell counts.
- High hematocrits can be seen in people living at high altitudes and in chronic smokers.
- Dehydration produces a falsely high hematocrit that disappears when the proper fluid balance is restored.
Some other infrequent causes of elevated hematocrit are
- lung disease,
- certain tumors,
- a disorder of the bone marrow known as polycythemia rubra vera, and
- abuse of the drug erythropoietin (Epogen) by athletes for "blood doping" purposes.
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Anemia: Common Causes, Symptoms, Types, and Treatment
Anemia is a disease marked by low numbers of red blood cells. Low iron deficiency or underlying disease, like cancer, may be to blame. Treatment can resolve anemia.
Anemia
Anemia is the condition of having less than the normal number of red blood cells or less than the normal quantity of hemoglobin in the blood. The oxygen-carrying capacity of the blood is, therefore, decreased. There are several types of anemia such as iron deficiency anemia (the most common type), sickle cell anemia, vitamin B12 anemia, pernicious anemia, and aplastic anemia. Symptoms of anemia may include fatigue, malaise, hair loss, palpitations, menstruation, and medications. Treatment for anemia includes treating the underlying cause for the condition. Iron supplements, vitamin B12 injections, and certain medications may also be necessary.
Blood Transfusion
During a blood transfusion, blood or blood products are transferred from one person to another. There are two types of transfusions, autologous (your own blood), and donor blood (someone else's blood). There are four blood types: A; B; C; and O.In addition, each person's blood is either Rh-positive or Rh-negative. It is important to know what to expect before, during, and after a blood transfusion, and the risks, side effecs, or complications of blood transfusions.
Cancer
Cancer is a disease caused by an abnormal growth of cells, also called malignancy. It is a group of 100 different diseases, and is not contagious. Cancer can be treated through chemotherapy, a treatment of drugs that destroy cancer cells.
Common Medical Abbreviations & Terms
Doctors, pharmacists, and other health-care professionals use abbreviations, acronyms, and other terminology for instructions and information in regard to a patient's health condition, prescription drugs they are to take, or medical procedures that have been ordered. There is no approved this list of common medical abbreviations, acronyms, and terminology used by doctors and other health- care professionals. You can use this list of medical abbreviations and acronyms written by our doctors the next time you can't understand what is on your prescription package, blood test results, or medical procedure orders. Examples include:
- ANED: Alive no evidence of disease. The patient arrived in the ER alive with no evidence of disease.
- ARF: Acute renal (kidney) failure
- cap: Capsule.
- CPAP: Continuous positive airway pressure. A treatment for sleep apnea.
- DJD: Degenerative joint disease. Another term for osteoarthritis.
- DM: Diabetes mellitus. Type 1 and type 2 diabetes
- HA: Headache
- IBD: Inflammatory bowel disease. A name for two disorders of the gastrointestinal (BI) tract, Crohn's disease and ulcerative colitis
- JT: Joint
- N/V: Nausea or vomiting.
- p.o.: By mouth. From the Latin terminology per os.
- q.i.d.: Four times daily. As in taking a medicine four times daily.
- RA: Rheumatoid arthritis
- SOB: Shortness of breath.
- T: Temperature. Temperature is recorded as part of the physical examination. It is one of the "vital signs."
Complete Blood Count (CBC)
A complete blood count (CBC) is a calculation of the cellular makeup of blood. A CBC measures the concentration of white blood cells, red blood cells, platelets in the blood, and aids in diagnosing conditions and disease such as malignancy, anemia, or blood clotting problems.
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COPD is a pulmonary disorder caused by obstructions in the airways of the lungs leading to breathing problems. Learn about COPD symptoms, diagnosis, and treatment options.
Diarrhea
Diarrhea is a change in the frequency and looseness of bowel movements. Symptoms associated with diarrhea are cramping, abdominal pain, and the sensation of rectal urgency. Causes of diarrhea include viral, bacterial, or parasite infection, gastroenteritis, food poisoning, and drugs. Absorbents and anti-motility medications are used to treat diarrhea.
Erythropoietin (EPO Test)
Erythropoietin (EPO) is a hormone created by the kidney. EPO promotes red blood cell formation via the bone marrow. Low levels of EPO may indicate anemia. Elevated EPO levels may indicate polycythemia rubra vera or hormone misuse by some athletes whose performance benefit from higher red blood cell counts. Such athletes include cyclists, long-distance runners, speed skaters, and Nordic (cross-country) skiers.
Hemoglobin: Normal, High, Low Levels, Age & Gender
Hemoglobin is the oxygen-carrying protein molecule in the blood, specifically in the red blood cells. High hemoglobin count may be caused by dehydration, smoking, emphysema, tumors, or abuse of Epogen. Low levels of hemoglobin may be caused by anemia, blood loss, nutritional deficiency, bone marrow problems, chemotherapy, kidney failure, or sickle cell disease.
Hemoglobin vs. Hematocrit
Hemoglobin is a protein in red blood cells and hematocrit is a measurement of the amount of red blood cells as related to total blood cell count. Both hemoglobin and hematocrit are used to diagnose anemia. Both hemoglobin and hematocrit can be measured from standard blood tests, and both values are typically reported when a doctor orders a blood count.
Kidney (Renal) Failure
Kidney failure can occur from an acute event or a chronic condition or disease. Prerenal kidney failure is caused by blood loss, dehydration, or medication. Some of the renal causes of kidney failure include sepsis, medications, rhabdomyolysis, multiple myeloma, and acute glomerulonephritis.
Post renal causes of kidney failure include bladder obstruction, prostate problems, tumors, or kidney stones.Treatment options included diet, medications, or dialysis.
Pernicious Anemia Picture
Pernicious anemia is a disease where large, immature, nucleated cells (megaloblasts, which are forerunners of red blood cells) circulate in the blood, and do not function as blood cells; it is a disease caused by impaired uptake of vitamin B-12 due to the lack of intrinsic factor (IF) in the gastric mucosa. It was termed "pernicious" because before it was learned that vitamin B-12 could treat the anemia, most people that developed the disease died from it.
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