Bone Marrow Aspiration

Indications

• Any unexplained leukocytosis, cytopenias, anemias
• Pyrexia of unknown origin
• Storage disorders
• Kala azar

Precaution

• Severe clotting disorders, e.g. hemophilia
• Fully aseptic technique must be employed using mask, gloves, gown and drapes
• Sites that have been irradiated should be avoided since they will not yield marrow
• Marrow aspiration from the posterior iliac crest is less hazardous and less painful than sternal aspiration. Because of the risks of penetration of the heart or great vessels, the sternal site is not usually recommended
• locate and sternal aspiration can be an easier technique
• The risks of sternal puncture are greater in the elderly and the osteoporotic, in whom the iliac crest is the recommended site
• Similarly, the iliac site is preferable in those who may require repeated marrow aspiration, e.g., in leukemia.

Technique

Posterior Iliac Crest Marrow Aspiration

• This is the recommended site:
• Position the patient prone, lying on a pillow placed beneath the pelvis or in the left lateral position
• Under strict aseptic precautions, cleanse the skin with an antiseptic, over the posterior iliac crest (often surface marked with a dimple)
• Infiltrate the skin over the posterior iliac crest with 1% lignocaine plain, down to and including the periosteum
• Using a Salah needle, draw up 2 ml of “sterile” sodium citrate into a 10 ml syringe and express all but a trace to delay clotting and avoid hemolysis
• Introduce the needle and stylet without the guard through the skin down to the periosteum and using a firm screwing motion, penetrate the periosteum. The “give” on entering the marrow cavity is less apparent than that which occurs using the sternal approach
• Remove the stylet from the needle. Warn the patient that pain may be experienced during aspiration. Then slowly aspirate 2 ml of the marrow
• Express the aspirate onto 6-8 glass slides and make lightly smeared marrow preparations (see needle aspiration cytology). If leukemia is suspected, remember to retain marrow blood. If military tuberculosis is a diagnostic possibility, send marrow blood for AFB culture?
• If the marrow preparations appear satisfactory, remove the needle and apply firm pressure to the puncture site for 3 minutes
• Cover the puncture site with a small sterile dressing. Watch the site daily for complications like osteomyelitis, which would not occur with strict aseptic technique.

Sternal Marrow Aspiration

The site of aspiration is immediately below the manubriosternal junction, opposite the second intercostal space with the point of entry just to one side of the midline since a sagittal bony septum may be present.

Technique

• Under strict aseptic precautions, cleanse with an antiseptic solution and anaesthetize.
• Infiltrate local anesthetic down to and including the periosteum.
• Use the anesthetic needle to gauge the depth of the periosteum from the skin surface.
• Set the guard on the Salah needle so that it is more than 5 mm above the skin surface when the top of the needle touches the periosteum. Alternatively, a Klima needle can also be used.
• Introduce the needle and stylet and on reaching the periosteum, “screw” it firmly into the sternum until it enters the marrow cavity with a characteristic “give”.
• Continue as for iliac crest approach.