Bone marrow aspiration and trephine biopsy

Bone marrow is the tissue inside our bones which makes blood. To assess this we can remove some by sucking out a small amount (an aspirate) and examining this in the laboratory. Sometimes a small core is also taken for testing (a trephine).

Why do I need a bone marrow aspiration?

To assess the blood forming cells normally found there and look for any abnormal cells. A small sample of bone marrow will be taken and examined under a microscope.

Where will I have this done?

A bone marrow sample can be taken as an outpatient in the Day Unit or on the ward. The procedure may be undertaken whilst you are lying on a bed in either the bay beds or in a side room.

How long will it take?

The whole procedure usually takes around 15 – 20 minutes.

What happens?

The bone marrow sample is taken under local anaesthetic from the back of the hip bone (pelvis) or breast bone (sternum). You will usually be asked to lie on your side or front. If the sternum is being tested you will lie on your back.

The skin is then cleaned with an antiseptic solution which may feel cold.

The skin and bone are injected with a local anaesthetic which may sting before becoming numb.

When the area is numb a needle is inserted through the skin into the bone. You may feel pressure at this stage. Then a small sample of marrow is drawn into a syringe. This may be painful but only lasts for a few seconds.

Sometimes a small sample of the marrow core is also needed (trephine biopsy). Another needle will be inserted at the same place to remove a core of bone marrow. You may feel pressure and a little discomfort for a short while.

Once the needle has been removed, pressure will be applied to the site before a dressing is put on. You will be asked to lie on your back for 10 minutes or so to prevent bruising.

The sample site will be covered with a small dressing which can be removed after 24 hours.

Are there any complications?

These are not common. When the local anaesthetic wears off, you may feel pain. Paracetamol is a useful painkiller for this. Avoid Aspirin as this can increase the risk of bleeding. If the pain becomes severe, contact your doctor.

Bleeding

If you are on Warfarin or any other blood thinning agent such as Rivaroxaban, then please tell the haematology doctor or specialist nurse when the test is arranged. Try to avoid Aspirin or Anti-inflammatory drugs in the five days before the tests. If your platelet (platelets help the blood to clot) count is very low you may need a platelet transfusion first. If after the procedure the site continues to bleed excessively, contact the Haematology Department.

Infection

The procedure is carried out using aseptic precautions. Occasionally the site of the test may become infected becoming painful and red. Contact the Haematology Department if this occurs. Please tell your doctor or nurse if you have any known allergies to lotions or dressings before the procedure.

If you have any questions about this leaflet, or about having a bone marrow aspiration, please ask a member of the medical or nursing team looking after you.

Please ask if you require this information in other languages, large print or audio format: call 01223 256998 or see our online Accessible information.