Kidney Functions and ESRD Basics
Key Takeaways
- Healthy kidneys remove metabolic wastes, regulate fluid and electrolytes, help maintain acid-base balance, and support blood pressure, red blood cell production, and bone health.
- ESRD means kidney function is no longer adequate to maintain internal balance without kidney replacement therapy.
- Hemodialysis replaces selected filtering and fluid-removal functions, but it does not replace every kidney function.
- CCHT exam scenarios usually test safe recognition, reporting, documentation, and following facility protocol, not independent diagnosis.
Why kidney function matters
Healthy kidneys filter blood continuously. They remove wastes such as urea, regulate sodium, potassium, bicarbonate, calcium, phosphorus, and water, and help control blood pressure, red blood cell production, and bone health.
In ESRD, these functions are no longer adequate to keep the internal environment stable. Hemodialysis removes selected solutes and water on a schedule, but it does not replace endocrine kidney functions or continuous regulation.
Technician focus
| Kidney function | Dialysis concern | CCHT-safe focus |
|---|---|---|
| Waste removal | Uremic symptoms | Report nausea, confusion, severe itching, or major change in condition. |
| Fluid balance | Edema, hypertension, shortness of breath | Compare weights, vital signs, and symptoms with the prescription and report concerns. |
| Electrolyte and acid-base balance | Potassium and acidosis risks | Know the ordered dialysate context and report weakness, palpitations, or abnormal symptoms. |
| Hormone-related functions | Anemia and bone-mineral disease | Reinforce the care plan and report symptoms or medication concerns to licensed staff. |
Before treatment, link findings to physiology without diagnosing. New shortness of breath may suggest fluid overload, weakness may relate to electrolyte or anemia concerns, and confusion or severe nausea can signal urgent problems.
On the exam, the safest answer is usually to verify, report, document, and follow facility policy. Do not start or change treatment just because a symptom seems common in dialysis.
A patient with ESRD asks what hemodialysis replaces most directly. Which response is most accurate for a CCHT?
Before treatment, a patient has new shortness of breath, ankle swelling, and a larger than usual weight gain. What is the safest first action?
Why do patients on hemodialysis still need diet, fluid, and medication plans?