What is one key difference between whole blood and packed cells?

Packed cells, also known as packed red blood cells (PRBCs), are derived from whole blood through a process that separates the red blood cells from the plasma and other components. One key difference is that packed cells contain significantly less plasma compared to whole blood, as the focus is on providing a concentrated source of red blood cells. This reduction in volume and plasma allows for more efficient transfusions where the primary goal is to increase the red blood cell count without introducing unnecessary fluids that could overload a patient.

In clinical practice, the use of packed cells is particularly important in situations where a patient may need red blood cell replenishment without additional plasma, such as in cases of anemia or significant blood loss. Whole blood has a complete composition of plasma, white blood cells, red blood cells, and platelets, which makes it suitable for different clinical needs, but it is not utilized as frequently for transfusions due to concerns about volume overload and other factors.

Therefore, the statement that packed cells do not have nearly as much plasma or volume as whole blood accurately reflects the essential distinction between the two types of blood products.