Sources of variability
1. Failure to aspirate marrow (a "dry tap") may
occur in a patient with a condition resulting in
excessive collagen disposition in the marrow. A
biopsy specimen must be obtain in such a
circumstance.
2. Rapid processing of the specimens is essential.
This is extremely difficult to do if the procedure
and the processing must be performed by the
same individual. It is desirable to have an assis-
tant or laboratory technician present to process
the specimens.
3. Correct technique in the processing of the speci-
mens is essential. It is usually best to have a
trained laboratory technician present to process
the specimens.
Medical Considerations
1. Reassurance of the patient is often necessary prior
to and during performance of the procedure.
2. In elderly individuals and in patients with
myeloma the bone may be soft. Take care not to
penetrate too deeply into bone.
3. At the end of the procedure, direct pressure
should be applied to the incision site until bleed-
ing has stopped. This may take a long time in
thrombocytopenic patients.
Specimen Collection Procedures A-7
