Small-Volume Blood Sample Tubes May Reduce Anemia and Transfusions in Intensive Care

Using small-volume rather than standard-volume collection tubes to draw blood for laboratory testing

may reduce the incidence of anemia and the need for red blood cell (RBC) transfusion in intensive care

(ICUs), according to a new study. The change does not appear to impair biospecimen sufficiency for lab

analysis.

In addition, by reducing blood transfusion during ICU admission by about 10 units per 100 patients, the

change may enable hospitals and health systems to sustain blood product supply during ongoing

shortages.

Reducing Blood Loss

Among ICU patients with critical illness, there is a high prevalence of anemia, Siegal noted. More than

90% of these patients have some degree of anemia after a 3-day stay. Typically, RBC transfusions are

given to correct the low blood counts, and as much as 40% of ICU patients receive at least one RBC

. Anemia and RBC transfusion are each associated with adverse outcomes, including higher mortality and

longer ICU and hospital stays.

Although anemia in critically ill ICU patients can have several causes, blood sampling can be substantial

because of the need to draw multiple tubes several times per day. During 8 days in an ICU, the amount of

blood drawn equals about 1 unit of whole blood, the authors noted, and ICU patients often struggle to

increase RBC production and compensate for blood loss.

Even then, only 10% of the blood collected is required for lab testing; the remaining 90% is often

discarded as waste, the authors noted. Small-volume tubes (1.8 to 3.5 mL), which are designed to draw

about 50% less than standard-volume tubes (4 to 6 mL) by using less vacuum strength, are of the same

size and cost as standard-volume tubes, and the collection technique is the same. They are produced by

same manufacturers and are compatible with existing lab equipment.