RBC Lifespan in preterm babies:
**Core Concept**
The lifespan of red blood cells (RBCs) in preterm babies is significantly shorter compared to full-term babies due to the immaturity of the reticuloendothelial system and the liver's inability to produce sufficient erythropoietin. This leads to a higher rate of RBC destruction and turnover.
**Why the Correct Answer is Right**
Preterm babies have a higher rate of RBC destruction due to the immaturity of the spleen, which is responsible for filtering and removing old or damaged RBCs from the circulation. Additionally, the liver's inability to produce sufficient erythropoietin, a hormone that stimulates RBC production, contributes to the shorter RBC lifespan. As a result, preterm babies require more frequent blood transfusions to maintain adequate oxygen delivery to tissues.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it does not accurately reflect the shorter RBC lifespan in preterm babies.
**Option B:** This option is incorrect as it suggests that the RBC lifespan is unaffected by prematurity, which is not supported by clinical evidence.
**Option C:** This option is incorrect as it implies that the RBC lifespan is longer in preterm babies, which is the opposite of the actual outcome.
**Clinical Pearl / High-Yield Fact**
Preterm babies are at increased risk of anemia due to the shorter RBC lifespan, which can lead to inadequate oxygen delivery to tissues and potentially life-threatening complications. Monitoring RBC indices and transfusing as needed is crucial to prevent anemia-related complications in preterm infants.
**Correct Answer:** C. 28 days