Haemoglobin (Hb) test overview

Haemoglobin is the main component of red blood cells and is responsible for their red hue. Its usual content in erythrocytes is 34%. Haemoglobin is a globular protein having chains of 141 and 146 amino acids, respectively. It exists as a tetramer, with each monomer possessing a heterocyclic porphyrin ring and iron constituting the heme.

Haemoglobin is a protein found in red blood cells that transports oxygen to organs and tissues and carbon dioxide from organs and tissues back to the lungs. If your haemoglobin level is lower than normal, it indicates that you have a low red blood cell count (anaemia). Anaemia can be caused by a variety of factors, including vitamin deficiencies, bleeding, and chronic disorders. If a haemoglobin test reveals a higher-than-normal level, there are various possible explanations, including the blood condition polycythaemia vera, high altitude living, smoking, and dehydration.

Haemoglobin is also vital in preserving the structure of red blood cells. Red blood cells are naturally spherical with narrow centres, resembling a doughnut without a hole in the middle. As a result, abnormal haemoglobin structure can distort the shape of red blood cells, impairing their function and passage through blood arteries.

Haemoglobin (Hb) test overview

Haemoglobin is the main component of red blood cells and is responsible for their red hue. Its usual content in erythrocytes is 34%. Haemoglobin is a globular protein having chains of 141 and 146 amino acids, respectively. It exists as a tetramer, with each monomer possessing a heterocyclic porphyrin ring and iron constituting the heme.

Haemoglobin is a protein found in red blood cells that transports oxygen to organs and tissues and carbon dioxide from organs and tissues back to the lungs. If your haemoglobin level is lower than normal, it indicates that you have a low red blood cell count (anaemia). Anaemia can be caused by a variety of factors, including vitamin deficiencies, bleeding, and chronic disorders. If a haemoglobin test reveals a higher-than-normal level, there are various possible explanations, including the blood condition polycythaemia vera, high altitude living, smoking, and dehydration.

Haemoglobin is also vital in preserving the structure of red blood cells. Red blood cells are naturally spherical with narrow centres, resembling a doughnut without a hole in the middle. As a result, abnormal haemoglobin structure can distort the shape of red blood cells, impairing their function and passage through blood arteries.

What exactly is a haemoglobin test?

The amount of haemoglobin in your blood can be measured using a haemoglobin test. Red blood cells are mostly made of a protein called haemoglobin (erythrocytes). Because iron is present in haemoglobin, it can bind to oxygen. Your red blood cells' ability to transport oxygen from your lungs to other tissues and organs throughout your body is due to haemoglobin. Your haemoglobin levels or amount can provide you hints about how well-functioning your red blood cells are. The diagnosis of blood diseases and other illnesses might be assisted by knowing your haemoglobin level by a healthcare professional. Anaemia, which results from having insufficient haemoglobin or healthy red blood cells, is frequently diagnosed with haemoglobin testing.

The cells in your body do not receive enough oxygen if you have anaemia. Measurements of haemoglobin are made as part of a complete blood count (CBC).

What is the purpose of a haemoglobin test?

• To evaluate your overall health. During a typical medical examination, your doctor may test your haemoglobin as part of a complete blood count to monitor your overall health and screen for many illnesses, such as anaemia.
• To determine the cause of a medical illness. If you're feeling weak, exhausted, have shortness of breath, or have dizziness, your doctor may recommend a haemoglobin test. These symptoms may indicate anaemia or polycythaemia vera. A haemoglobin test may aid in the diagnosis of these and other medical disorders.
• To keep track of a medical condition. If you have anaemia or polycythaemia vera, your doctor may order a haemoglobin test to monitor your status and guide your therapy. A standard physical examination by your doctor may include a haemoglobin test. The number of red blood cells, white blood cells, and platelets in a blood sample is determined by a complete blood count (CBC) test, which includes haemoglobin assays. Your doctor can evaluate your health using this information and check for specific diseases.

If you exhibit signs of diseases associated with low haemoglobin levels or high haemoglobin levels, your doctor may potentially order a haemoglobin test for you.

Low haemoglobin level

Too few red blood cells (RBC) or low haemoglobin levels can deprive your tissues and organs of the oxygen they require to produce energy and keep you healthy. The following are the indications of low haemoglobin levels:

• Fatigue
• Light skin colour (paleness)
• Tiredness
• Dizziness
• Breathing difficulty
• Cold feet and hands

High haemoglobin level

An excessive number of red blood cells or a high level of haemoglobin might cause your blood to thicken and slow down. Because thick blood does not flow as quickly, your organs aren't getting enough oxygen. The following are signs of elevated haemoglobin:

• Headaches
• Double or blurred vision
• Dizziness
• Itching
• Clots of blood

How to get prepared for the haemoglobin test?

There is no particular preparation necessary for a haemoglobin test. Only a few minutes are needed. A medical laboratory, your provider's office, or another outpatient location are all options for getting tested. A haemoglobin test could be combined with other blood tests that call for you to fast (without eating or drinking) for a set period before the test in some cases. To be ready, follow the advice from your physician.

The procedure for the haemoglobin test

• Your doctor will take a blood sample from your hand or arm. They can pierce your finger to get blood as well.
• Your doctor will first wipe some alcohol onto your skin. To facilitate easier blood flow, they will wrap an elastic band over your upper arm and instruct you to make a fist. They will next place a tiny needle into a vein. The needle may sting as it is inserted. The needle will draw your blood and deposit it into a container.
• In the end, the bottle will be sent to a lab for evaluation by your provider.

Haemoglobin test result interpretation

A haemoglobin test can determine whether your levels are too low, as in anaemia, or too high. It can also indicate the severity of your disease. The haemoglobin level is measured in grammes (gm) per decilitre (dL) of whole blood, with a decilitre equalling 100 millilitres.

The normal levels for haemoglobin vary on the person's age and, beginning in adolescence, gender. The normal haemoglobin range is:

• 13.2 to 16.6 grams per decilitre for Males
• 11.6 to 15 grams per decilitre for Females

Children's healthy weight ranges differ depending on their age and gender. The range for a healthy haemoglobin level varies slightly amongst medical practices.

Low levels

You have anaemia if your haemoglobin level is below normal. Anaemia comes in a variety of types, each with a unique set of reasons, such as:

• Deficit in iron
• B-12 vitamin deficiency
• Folic acid deficiency
• Bleeding
• Bone marrow-related cancers like leukaemia
• kidney illness
• Liver illness
• Hypothyroidism
• Low quantities of haemoglobin and red blood cells are a result of the hereditary condition thalassemia.

High levels

Your haemoglobin level may be greater than usual for a variety of reasons, including:

• A blood illness called polycythaemia vera causes your bone marrow to produce an excessive amount of red blood cells.
• Lung disorder
• Dehydration
• Residing in an alpine environment
• Excessive smoking
• Burns
• A lot of vomiting
• Intense physical activity