Improving Residents' Knowledge of Peripheral Smears

Background: A peripheral smear is an important diagnostic tool, inexpensive, reliable and quick. It reflects the functional status of the bone marrow and can identify many blood disorders, some of which are life threatening and very time sensitive. Peripheral smears are useful to assess cytopenic states (eg, anemia, leukopenia, thrombocytopenia) or identify hematologic emergencies such as thrombocytopenic purpura/hemolytic uremic syndrome, acute myeloid leukemia, and disseminated intravascular coagulation etc. Sometimes it is sufficient to make a diagnosis solely based on them which can be life saving when time is of the essence. Based on our literature search, there are no studies to assess internal medicine residents' knowledge and understanding of peripheral smears.

Methods: We created a multiple-choice questions survey of 13 questions for residents to fill out, involving common findings on peripheral smears and those found in hematologic emergencies that every resident should be aware of. Response rate in all three program years (PGY) was 100%. 16/16 PGY-1, 10/10 PGY-2 and 9/9 PGY-3 completed the survey.

Results: Average pre-intervention score for PGY-1 was 42%, PGY-2 was 34% and PGY-3 was 30%. Questions most commonly wrong were regarding target cells, metamyelocytes, giant platelets and schistocytes. Most were correct about microcytosis and Auer rods. We then conducted the same survey weeks after our intervention, which was interactive, small group didactics sessions on peripheral smears. We compared results of the survey before and after didactics to check for improvement. Post-intervention score for PGY-1 was 98%, PGY-2 and PGY-3 were 96%.

Conclusions: Most medical residents are not aware of common interpretations of peripheral smears and this does not seem to improve with each progressive year. Improving residents' knowledge of peripheral smears is a cost effective and quick measure that can improve patient care, in addition to potentially improving internal medicine board results. In the future, we aim to make a curriculum for peripheral smear review for residents. We can compare results of the survey with hematology oncology fellows.