**Question:** A CKD patient on haemodialysis complains of chest pain and back pain after five minutes of dialysis initiation. On reassurance by nurse he feels gradually better and the symptoms resolve on their own. What is the cause?

**Core Concept:** The described symptoms are consistent with the phenomenon of **dialysis-induced hypovolemia** or **dry-dialysis syndrome**. This occurs when the patient experiences a decrease in intravascular volume during hemodialysis, due to fluid removal, ultrafiltration, and/or excessive bleeding.

**Why the Correct Answer is Right:** In the described scenario, the patient experiences relief from pain symptoms after the nurse's reassurance, suggesting that the hypovolemia is causing the patient's distress. Reassurance leads to a sense of comfort and improved blood volume, alleviating the hypovolemia-induced symptoms.

**Why Each Wrong Option is Incorrect:**

A. **Hypotension (low blood pressure)**: Although hypotension can contribute to the patient's discomfort, it is not the primary cause of the described symptoms. Hypovolemia is more likely to result in chest pain, back pain, and anxiety, which is resolved by reassurance.

B. **Hypoxia (low oxygen levels)**: Hypoxia is unrelated to the described symptoms, which are primarily related to hypovolemia. While hypoxia may worsen the patient's discomfort, it does not explain the relief provided by reassurance.

C. **Hypoglycemia (low blood sugar)**: Hypoglycemia is not relevant to the patient's symptoms caused by hypovolemia. Reassurance does not address hypoglycemia.

D. **Hypothermia (low body temperature)**: Hypothermia is unrelated to the patient's symptoms caused by hypovolemia. Reassurance does not treat hypothermia.

**Clinical Pearl:** Dialysis-induced hypovolemia is a common issue in hemodialysis patients, especially those with CKD. Recognizing and managing hypovolemia is crucial for patient comfort and safety during hemodialysis sessions.

**Correct Answer:** D. **Hypovolemia (low blood volume)**: Hypovolemia is the primary cause of the patient's discomfort, including chest pain, back pain, and anxiety. Reassurance from the nurse alleviates the patient's distress, indicating that the patient's symptoms are related to the improvement in blood volume caused by reassurance.