Cold Storage: Can Blood Cells Handle the Chill?

Red blood cells are usually kept between 2 and 6 degrees Celsius. This is the standard in Europe. But what if they get colder? Much colder. What if they get exposed to temperatures below zero? This is a real concern. Sometimes, blood cells get too cold, especially when they are being transported to hospitals. This can happen before they are even used in a transfusion. So, a study was done to see if this cold exposure affects the quality of the blood cells. Three groups of packed red blood cells were used. Each group had 14 samples. These groups were exposed to different cold temperatures. One group was put at -1 degree Celsius, another at -5 degrees Celsius, and the last group at -11 degrees Celsius. This happened on the sixth day after the blood was donated. The groups were kept at these temperatures for 10 hours. Then, they were compared to a control group that was kept at the usual storage temperature. The researchers looked at several things. They checked for hemolysis, which is when red blood cells break open and release their contents. They also measured the pH levels and the chemistry of the plasma. Additionally, they counted the number of storage-induced micro-erythrocytes, or SMEs. These are tiny red blood cells that form during storage. They can indicate how well the blood cells will work after being transfused. The primary goal was to see if the blood cells met European storage standards by the 42nd day. The results were interesting. All three groups that were exposed to sub-zero temperatures met the storage standards by day 42. There were no big differences in hemolysis, pH, plasma chemistry, or the number of SMEs between the exposed groups and the control group. This means that the blood cells kept their quality even after being exposed to very cold temperatures. So, what does this mean? It shows that packed red blood cells can handle being very cold for a short time. This is important for making decisions about using blood cells in transfusions. It also helps in assessing the risks involved. However, it is crucial to remember that this study only looked at a specific situation. More research is needed to fully understand the effects of cold exposure on blood cells. This is especially true for longer periods of time or different conditions. Also, the study did not look at how the blood cells would work in a real-life transfusion. This is an important area for future research.