Definition & Overview
The bone marrow is a soft, spongy tissue found inside the bone. It is vital for the production of blood cells including the red and white blood cells as well as platelets. These cells are produced in large bones such as the skull, ribs, hips, spine, and breastbone.
The blood cells and platelets are vital for survival. The red blood cells transport oxygen and nutrients to all parts of the body while the white blood cells protect the body from infections. Platelets, on the other hand, play a key role in blood clotting.
A bone marrow aspiration is different from a bone marrow biopsy. The latter removes a part of the bone, the marrow, and the fluid inside and examines them under a microscope. A bone marrow aspiration, on the other hand, only examines the marrow. It is performed to check for any blood-related diseases or abnormalities.
The patient’s marrow can either be red or yellow. Red marrow can be extracted from the hip and vertebrae while a yellow marrow is a red marrow that has saturated with fat cells.
Doctors aspirate the red marrow from the bones, which is then sent to a medical laboratory for examination. The pathology lab will check if the bone marrow is producing healthy blood cells or if there are any abnormalities in the cells being produced in the body. The lab results will reveal any infections, cancer, and other types of bone marrow diseases.
Who Should Undergo and Expected Results?
The procedure is often performed in patients with an abnormally high or low blood cells (white, red, and platelets) count. Abnormalities and diseases commonly diagnosed using the procedure include:
- Anaemia - A condition marked by a deficiency of haemoglobin or red blood cells that results in an unhealthy pale appearance and extreme tiredness
- Aplastic anaemia – A condition wherein the bone marrow is unable to produce enough blood cells thereby giving the patient an overall feeling of fatigue. The condition also increases the risk of blood infections and bleeding.
- Myelofibrosis or myelodysplastic syndrome – Common types of bone marrow diseases
- Bone marrow cancer, such as leukaemia or lymphomas
- Haemochromatosis - A hereditary metabolic disorder wherein iron salts are deposited in various tissues of the body. This excess iron in the tissues can damage the organs, joints, and can lead to death
- Hodgkin or non-Hodgkin lymphoma
- Idiopathic thrombocytopenic purpura (ITP)
- Multiple myeloma
- Primary thrombocytopenia
- Waldenstrom macroglobulinemia
How is the Procedure Performed?
Patients will need to tell their doctor if they have a bleeding disorder or are currently taking any medication.
The doctor will need to know the patient’s medical history, including any allergies to food and drugs. If the patient is a woman, the doctor will need to know if she’s pregnant or planning to have a baby. If the patient is feeling anxious about the entire procedure, the doctor may administer medication to help the patient relax.
A bone marrow aspiration is a simple medical procedure that can be performed using a mild sedative. It can be done in a hospital or clinic with a skilled or trained physician.
Before the procedure starts, the physician’s assistants will take the patient’s heart rate and blood pressure, which are monitored all throughout the procedure.
The doctor will then clean the area where the needle will be inserted. Once cleaned, a needle with anaesthesia or sedative drug is injected to numb the area and the surrounding bones. A special kind of needle is then used to aspirate the bone marrow. The needle is connected to a tube that creates suction so the obtained sample flows through the tube into a container.
When an enough amount of bone marrow is obtained, the needle is removed. The insertion area is applied with pressure and a bandage is used to stop the bleeding, if there's any.
The test can result in a slight burning sensation due to the medicine used. As the doctor aspirates the marrow from the bone, a sharp pain is felt but only lasts for a few seconds. The whole procedure only lasts about 10 minutes.
The doctor may ask the patient to stay for an hour or two in the hospital or clinic for observation before being allowed to go home. Any post-procedural pain is managed with over-the-counter pain relievers. The incision has to be kept dry and must be regularly cleaned to avoid infection.
The doctor will schedule a follow-up appointment to go through the lab result with the patient. Any abnormal findings will warrant further tests or treatment.
Possible Risks and Complications
Complications arising from a bone marrow aspiration are rare. These include:
- Infection, which can be treated with medications
- Allergic reaction to the anaesthesia
- Nagging or persistent pain in the area where the procedure was performed. The pain can be managed by taking pain relievers or analgesics.
Patients with a weak immune system may be at a higher risk of acquiring bacterial infections while those diagnosed with a low platelet count may suffer from increased bleeding during and after the procedure.
Quesada AE, Tholpady A, Wanger A, Nguyen AN, Chen L. Utility of bone marrow examination for workup of fever of unknown origin in patients with HIV/AIDS. J Clin Pathol. 2015 Mar. 68(3):241-5. [Medline].
Sokolowska B, Skomra D, Czartoryska B, Tomczak W, Tylki-Szymanska A, Gromek T, et al. Gaucher disease diagnosed after bone marrow trephine biopsy - a report of two cases. Folia Histochem Cytobiol. 2011. 49(2):352-6.