Shelf life of blood with CPDA
**Core Concept**
The shelf life of blood is determined by the anticoagulant-preservative solution used, with CPDA (Citrate-Phosphate-Dextrose-Adenine) being one of the most commonly used solutions. CPDA helps to prevent blood coagulation and maintain red blood cell viability by providing glucose, phosphate, and adenine, which are essential for red blood cell metabolism.
**Why the Correct Answer is Right**
The CPDA solution contains adenine, which is a precursor to ATP (adenosine triphosphate) in red blood cells. Adenine helps to maintain the ATP levels in red blood cells, thereby preventing the breakdown of 2,3-bisphosphoglycerate (2,3-BPG), a critical molecule that regulates oxygen delivery to tissues. The combination of CPDA's glucose, phosphate, and adenine helps to maintain red blood cell viability for up to 35 days. This extended shelf life is crucial for blood banks and transfusion services.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not provide sufficient information about the shelf life of blood with CPDA.
**Option B:** This option is incorrect because it suggests a shorter shelf life than is actually possible with CPDA.
**Option C:** This option is incorrect because it implies that CPDA does not provide any benefits for red blood cell viability.
**Clinical Pearl / High-Yield Fact**
It's essential to note that the shelf life of blood with CPDA can be extended to 42 days when stored at 4°C and with gentle agitation. This extended shelf life is crucial for blood banks and transfusion services, particularly in areas with limited access to fresh blood supplies.
**Correct Answer: B. 35 days**