In the process of hemodialysis, when anti-heparin is being added?

Options

A. After the blood is taken out from an artery
B. Before the clear blood is pumped back to the body through a vein
C. Into the body before the blood is taken out for the process
D. Into the body after the cleared blood in injected into the veins.

Answer

### Step-by-Step Solution:

1. **Understanding Hemodialysis**: Hemodialysis is a medical procedure used to remove waste products, such as urea, from the blood when the kidneys are not functioning properly. This condition, known as uremia, can be harmful and may lead to kidney failure.

2. **Process of Hemodialysis**: During hemodialysis, blood is drawn from the patient's body through a convenient artery. This blood is then transported to a dialysis unit, often referred to as an artificial kidney.

3. **Role of Anticoagulants**: To prevent the blood from clotting during the dialysis process, an anticoagulant is added. Heparin is a commonly used anticoagulant in this context.

4. **Timing of Anticoagulant Addition**: The anticoagulant (heparin) is added to the blood after it has been drawn from the artery but before it enters the dialysis unit. This ensures that the blood remains fluid while it is being processed.

5. **Returning Blood to the Body**: After the blood has been cleaned of waste products in the dialysis unit, it is then pumped back into the patient’s body through a vein. Before this return, anti-heparin is added to ensure that the blood does not clot as it re-enters the circulatory system.

6. **Conclusion**: Therefore, the correct timing for the addition of anti-heparin in the hemodialysis process is before the clear blood is pumped back into the body through a vein.

### Final Answer:
Anti-heparin is added **before the clear blood is pumped back to the body through a vein**.

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