Drawing a patient's blood for laboratory testing, or "diagnostic phlebotomy," is among the most commonplace hospital practices. But a recent study found that greater use of diagnostic phlebotomy is independently associated with the development of anemia in hospitalized patients with myocardial infarction (MI)-and anemia in this population is associated with higher mortality rates and worse health status.

Researchers examined data on 17,676 patients admitted to 57 hospitals from January 1, 2000, through December 31, 2008. All patients had a diagnosis of acute MI; none had anemia at admission. The investigators found that more than 20% of patients developed moderate-to-severe hospital-acquired anemia (HAA), and the amount of blood taken for diagnostic purposes from these patients was about 90 mL greater than from those who didn't develop HAA.

Although the authors focused their study on patients with MI, they believe that the negative association between phlebotomy and anemia will likely translate to other patient populations, and although some factors contributing to HAA aren't modifiable, diagnostic phlebotomy is clearly under the control of health care providers. They stressed the need to reduce blood loss by using pediatric tubes, for instance, or drawing less blood into adult tubes.

Sherri Ozawa, clinical director of the Institute for Patient Blood Management and Bloodless Medicine and Surgery at Englewood Hospital and Medical Center in Englewood, New Jersey, thinks that a change in equipment would help but would also like to see institutional protocol changes to eliminate routine blood testing. "We see an excessive amount of blood drawing, just because it's always been done that way," she told AJN.

Ozawa is calling upon nurses to question the need for drawing blood when it seems excessive and to look for ways to gauge a patient's status (by looking at symptoms, for instance) without depending on laboratory studies. She noted that, particularly at teaching hospitals, where residents call for frequent laboratory tests, nurses need to speak up and ask why.

"Good old-fashioned medical care will often give you the information you need before a blood draw would," she said.-Laura Wallis

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