Bone marrow procedures move into the 21st century

KENNETH SYMINGTON, MD

FELIX MARTINEZ, JR., MD

For many years, the standard methods of performing bone marrow procedures in patients with varying bone densities have remained unchanged. This is despite the fact that the manual method of performing bone trephine biopsies has significant limitations, including patient discomfort, needle-related adverse events, and operator dependence.

The new and developing field of intraosseous medicine is finally bringing much-needed change to bone marrow procedures. Intraosseous (IO) vascular access was commonly used by World War II medics to resuscitate soldiers dying from hemorrhagic shock. The technique of infusing fluids and drugs into patients in trauma and resuscitative situations via IO space fell out of favor once the war ended. But in the 1980s, a pediatrician from the Cleveland Clinic observed IO being used during a cholera epidemic in India, and the technique became standard in pediatric advanced life support.

More recently, the American Heart Association and other international organizations have recommended that it be employed as a first alternative to delayed or failed IV via peripheral vascular access. Now IO has been adapted for use in bone marrow procedures.

In this article, we offer a brief history of bone marrow procedures and how the IO approach is revolutionizing the field (see Table).

Drawbacks of manual manipulation

Bone marrow samples are difficult to evaluate and are plagued by varying consistency. In one large study, the investigators noted that only 42% of their biopsy specimens were adequate for accurate diagnosis (J Clin Path 45:1105-1108, 1992).

Inadequacy of specimens has huge significance. The patients who come to us may be seriously ill; their treatment depends on the accuracy of the diagnosis we render. To do this properly, we need core samples of sufficient size and as free as possible from crush artifact and trabecular distortion. It stands to reason that the larger the amount of tissue taken, the greater the chance of detecting focal lesions.

The manipulation of the needles used to retrieve the samples is an influential factor in sample quality: The less manipulation, the greater the possibility of achieving an intact sample of sufficient size. Getting good core samples has historically been highly dependent on operator expertise. Even with experience, approximately 5% of procedures result in "dry taps," or no specimens (Yonsei Med J 27:100-105, 1986). A significantly higher percentage (20%) yield inadequate amounts of tissue. Acquisition of samples of sufficient size with good cellular viability in as short a time as possible is the key objective of bone marrow biopsy and aspiration. Current manual techniques often limit our ability to do this.

Then there is the problem of patient discomfort and pain. A complete bone marrow biopsy with manual techniques can take up to 30 minutes. Studies have shown that duration of the procedure is the most important factor influencing the intensity of patient pain (Acute Pain 6:9-14, 2003). Patients with hard bones often suffer a great deal because of the difficulty of accessing the marrow space (often described as a "non-collapsible" vein).

With imaging guidance, interventional radiologists who perform bone marrow procedures offer conscious sedation, which can reduce procedure-related pain. Still, with manual needles we often need to "muscle" patients whose bones are particularly hard or in whom the lesions are difficult to locate. Often we have problems securing the needle to stand on top of the bone cortex.

In addition to pain, there is the morbidity and mortality associated with bone marrow procedures, even those carried out by experienced operators. A 2003 retrospective series highlighted some of the more common adverse events, including needles breaking off the manual devices and being left behind in the patient (Br J Haematol 121:949-951, 2003).