Storage Lesion

Now that's a office style storage lesion!

Blood transfusions have saved countless lives by replacing lost or deficient blood components, such as red blood cells (RBCs), platelets, and plasma. However, the quality and effectiveness of blood products can be affected by storage time, leading to a set of changes known as storage lesion. In this article, we'll explore what storage lesion is, how it affects blood products, and why fresher blood may be better for some people.

What is Storage Lesion in Blood Products?

Storage lesion refers to the changes that occur in blood products over time, particularly during refrigerated storage. These changes can affect the viability, function, and safety of the blood components, and may vary depending on the type of product and storage conditions. Some of the common changes associated with storage lesion in blood products include:

• Reduced levels of adenosine triphosphate (ATP), which is essential for energy metabolism and cell membrane integrity;
• Increased levels of reactive oxygen species (ROS), which can damage cell membranes, proteins, and DNA;
• Loss of membrane flexibility and deformability, which can impair oxygen delivery and hemostasis;
• Alterations in blood cell surface markers and activation status, which can affect immune responses and thrombosis;
• Changes in coagulation factors, complement proteins, and cytokines, which can modulate inflammation and immune reactions.
• Decreased pH: During storage, the pH of blood products can decrease, which can impair the function of enzymes and other proteins in the blood.

These changes can have important clinical implications for patients who receive transfusions, especially those who are critically ill, have underlying diseases, or require frequent transfusions. For example, storage lesion in RBCs can cause an increase in potassium levels and an increase in free hemoglobin, which can lead to hyperkalemia and hemolysis in susceptible patients. Moreover, storage lesion can compromise oxygen delivery, exacerbate inflammation, and increase the risk of transfusion-related complications, such as transfusion-associated circulatory overload (TACO), transfusion-related acute lung injury (TRALI), and transfusion-transmitted infections (TTIs).

Platelet Storage Lesion

During platelet storage, several biochemical and physiological changes can occur, collectively known as the platelet storage lesion. Some of the common changes associated with the platelet storage lesion include:

• Loss of platelet function: Platelets stored for longer durations may become less effective at forming blood clots or adhering to damaged blood vessels.
• Activation of platelets: Platelets can become activated during storage, leading to the release of proinflammatory and procoagulant substances, such as cytokines, thromboxane A2, and platelet factor 4.
• Loss of platelet viability: Platelets can undergo apoptosis or programmed cell death during storage, leading to a reduced number of viable cells.
• Changes in platelet membrane structure and composition: Platelets stored for longer durations may undergo structural changes in their membranes, such as increased lipid peroxidation, which can impair their function and survival.
• Bacterial contamination: Platelet storage bags and units can become contaminated with bacteria, which can cause transfusion-related infections and other complications.

Why Fresher Blood May Be Better for Some People?

Given the potential adverse effects of storage lesion in blood products, researchers and clinicians have explored various strategies to minimize its impact. One of these strategies is to use fresher blood, i.e., blood that has been stored for a shorter duration. This approach is based on the hypothesis that fresher blood has fewer storage lesions and, therefore, may be more effective and safer for some patients.

Several studies have investigated the association between blood storage time and clinical outcomes in various patient populations. For example, a randomized controlled trial published in the New England Journal of Medicine in 2015 found that transfusion of fresher RBCs (stored for less than 10 days) did not improve mortality or morbidity in critically ill adults compared to standard-issue RBCs (stored for up to 42 days). However, the study also showed that fresher blood was associated with a lower risk of new-onset multiple organ failure, suggesting a potential benefit for specific subgroups of patients.

Another study published in JAMA in 2021 analyzed data from nearly 300,000 transfusions in more than 80,000 patients and found that fresher RBCs were associated with a lower risk of in-hospital mortality and complications, especially in patients with sepsis, acute respiratory distress syndrome (ARDS), and cardiac surgery. The study also reported that fresher RBCs had higher levels of ATP, lower levels of potassium, and less hemolysis than older RBCs, supporting the hypothesis that storage lesion contributes to the adverse effects of blood transfusions.

However, using fresher blood may not be feasible or cost-effective in all settings. Physicians should order and use judiciously, and transfusion centers should be sure to double check with the physician before proceeding.