An assistant should now apply pressure for a couple of minutes with a sterile gauze pad over the entrance wound to prevent seepage or haematoma formation. You should be able to see clumps of marrow within the fluid sample. Repeat this process to make 3 or 4 smears. If your sample clots quickly it may be pure blood. In this case you may have to repeat the procedure, moving along the iliac crest slightly.
Air dry the slides, then fix in methanol for a few minutes.
Remove from the methanol and air dry again before staining or submitting to a lab. Ideally, further aspirated samples should be fixed in formalin to allow an assessment of the overall cellularity of the bone marrow.