Safety Profile of Bone Marrow Aspiration and Biopsies Performed By the Hospitalist Procedure Service at an Academic Center: An Observational Study
Authors: Obasi Jennifer U , Umpierrez De Reguero Adrian P 
Published: November 2019

Background: Bone marrow sampling is an invasive procedure that can be obtained by aspiration and biopsy(also called trephine biopsy) and as such, requires good technical skills to avoid complications and increase diagnostic yield. Aspirate and biopsy samples are complementary and when obtained together, are an invaluable tool toward obtaining an accurate and comprehensive profile for cellular, cytogenetic, immunophenotypic and cytological assessments. Bone marrow aspiration and trephine biopsy are generally regarded as relatively low risk procedures, however, factors that should be taken into consideration include disseminated intravascular coagulopathy, factor deficiencies, skin infections, and severe thrombocytopenia. In adults, the posterior iliac crest is often the preferred site but other accessed sites include the sternum (aspiration only) and anterior superior iliac crest in obese patients.For procedures performed at the posterior iliac spine, possible complications include pain, bleeding and infection.
The hospitalist procedure service is a relatively newer advent that make up a subset of hospital medicine practice, mostly in larger academic centers. They are made up of internal medicine faculty with additional procedural training and expertise in bedside procedural care. Depending on the institution, the service performs a variety of procedures with lumbar punctures, thoracentesis and paracentesis, comprising a bulk of them. Other services include bone marrow sampling, arthrocentesis and chest tube placement. The long term impact of procedure services on inpatient hospital teams continues to be an ongoing area of research, but so far, studies have shown that these services have been associated with an increase in best practice safety process measures, increased patient satisfaction, and faster access to procedures without increasing complication rates.
At our institution, this procedure is performed by hematology/oncology staff and fellows and advanced practice providers (APP) in collaboration and with direct supervision by an attending physician. Direct supervision is usually unnecessary once competency is determined. Other services qualified to provide this service at our institution include the inpatient hospitalist bedside procedure service (HBPS) and interventional radiology (particularly if needed under computed tomography (CT) guidance). Other than those performed by hematology/oncology providers, the HBPS at our institution is responsible for the majority of bone marrow aspiration and biopsies performed at the bedside.
Methods: We reviewed procedure records kept by the inpatient HBPS from February 2017 through May 2019. Most bone marrow sampling were performed on patients on the adult inpatient hematology/oncology service. Other inpatient services represented included Internal Medicine, Physical Medicine and Rehabilitation (PM&R), Cardiology and Transplant (Surgical and Medical). Informed consent was obtained from all patients and/or patient surrogates. All procedures were performed at either the right or left posterior iliac crest using a powered bone marrow biopsy device (Teleflex Arrow On-Control) with an 11 gauge bone access needle, either 4 or 6 inches in length. The site was obtained via landmarks with the patient in either the prone or lateral decubitus position. Specific orders for the procedure were placed by the inpatient clinician/practitioner requesting the procedure. A technician was present at bedside to prepare slides.
Results: Of the 233 patients on which bone marrow aspirates and/or biopsies were attempted, 217 (93%) were performed successfully. 16 (7%) were unsuccessful with those patients subsequently referred to interventional radiology for placement under CT guidance. Of the procedures which were successful, 181 (83.4%) were successful with the first attempt, while 36 (16.6%) required more than one attempt. 1 (0.4%) patient experienced a procedural complication secondary to a hematoma.
Conclusions: We propose that bone marrow sampling performed by a hospitalist procedure services is a safe and efficacious option and alternative for busy inpatient hematology/oncology services as it can provide faster access to care for patients who need the procedure. It also helps liberate hematology/oncology providers from performing these procedures to allow them the opportunity to focus on patient care and rounds.

Disclosures
No relevant conflicts of interest to declare.