The method for extracorporeal removing waste products and free water from the blood when the kidneys are in renal failure is called?

• A. Nephrectomy
• B. Renal transplant
• C. Hemodialysis
• D. Peritoneal dialysis

Answer: (C)

When kidneys fail, the body can no longer remove waste products and extra water from the blood. The method that cleans the blood outside the body using a machine is hemodialysis. In this process, blood is drawn from the patient and passes through a dialyzer, a filter with a semipermeable membrane. On one side of the membrane is the patient’s blood; on the other side is a special dialysis solution. Waste products and excess water diffuse into the dialysis fluid and are removed, while essential components like certain electrolytes can be balanced. The cleaned blood is then returned to the body. This extracorporeal filtration mimics kidney function to maintain chemical balance and fluid status.

Nephrectomy would remove a kidney, reducing filtration capacity rather than replacing it. A renal transplant replaces a failed kidney with a donor organ. Peritoneal dialysis uses the lining of the abdomen as the filter, with dialysis fluid infused into and drained from the abdomen—not an extracorporeal machine-based process.