A guide to performing a bone marrow aspiration

1. Decide on the most appropriate site for aspiration;

• The usual site for puncture in adults is the posterior superior iliac spine (PSIS).
• This may be technically difficult in obese or immobile subjects.
• The main advantage of this site is that a trephine biopsy can also be performed. Alternatively the sternum ( manubrium or 1^st or 2^nd parts of the body) can be used with care as there is a danger of  perforating the inner cortical layer and damaging the underlying large blood vessels and right atrium with serious consequences.

2. Obtain informed written consent;

• The procedure (in brief) and its main adverse effects (although rare) should be explained to the patient prior to obtaining consent.
• Pain, bleeding/haematoma formation and infection at aspiration site are the most commonly seen adverse effects, however, very rarely cause major concern.

3. Positioning the patient;

• Either left or right lateral decubitous on a bed/couch, with the dorsal surface of the patient facing the operator.
• Hold the hips and knees flexed to a comfortable maximum – knees drawn up and tucked into chest.