Plasma donation involves drawing blood, separating the plasma using an apheresis machine, and returning the remaining components to the donor. This protein-rich liquid is used to create life-saving therapies for people with rare and chronic diseases. Centers enforce strict safety rules to protect both the donor and the quality of the final product. A common reason for temporary deferral is the presence of a bruise at the venipuncture site, a rule rooted in procedural efficiency and medical safety.
The Anatomy of a Bruise and Vein Access
A bruise, or hematoma, forms when small blood vessels (capillaries) are damaged beneath the skin. This damage causes blood to leak out and collect in the surrounding soft tissue. The resulting discoloration is pooled, clotted blood that the body must absorb over time.
Plasma donation requires precise access to a healthy, structurally sound vein for a successful collection. A bruise indicates that the vascular integrity of the tissue immediately surrounding the vein is compromised. Inserting a large-gauge needle into an area that is already inflamed and damaged significantly increases the difficulty of the venipuncture.
Critical Safety Risks During Plasma Collection
The primary concern with donating through a bruise is the risk of worsening the existing hematoma and causing severe discomfort. A recently damaged vein is more likely to rupture, or “blow,” upon re-puncture, leading to a much larger collection of blood under the skin and immediate procedural failure. This risk of procedural complication is too high for centers to permit the attempt.
A second safety consideration is the possibility of localized infection. Bruised tissue represents a site of trauma, and the skin barrier over that area may be weakened or compromised. Although the venipuncture site is cleaned thoroughly with an antiseptic solution, puncturing through damaged tissue can increase the opportunity for localized bacteria to enter the bloodstream. Centers minimize any risk of introducing contaminants to the donor’s system.
Finally, the integrity of the collected plasma product is a concern. The bruise consists of red blood cells and cellular debris that have leaked from the vessel. If the needle is inserted near this damaged tissue, this localized cellular material could be drawn into the collection tubing. The presence of excess red blood cells, or hemolyzed blood, compromises the purity and quality of the collected plasma, rendering the entire donation unsuitable for therapeutic products.
Guidelines for Re-Donation After a Bruise
The disqualification associated with a bruise is temporary and applies only to the specific arm or site where the discoloration is present. A minor bruise typically begins to fade quickly, but larger hematomas may take up to two or three weeks to be completely absorbed. The healing process is marked by the bruise changing color from a dark blue or purple to green, then yellow, before fully fading.
A donor may only return to use the affected arm once the venipuncture site is completely clear of any discoloration and tenderness. The tissue must be fully healed beneath the skin to ensure the vein is structurally ready for another donation and to minimize the risk of pain or further injury. This policy extends to other localized skin issues, such as rashes or open cuts, ensuring the skin at the access site is healthy and intact.