Kidney failure is an alarming diagnosis, but if managed appropriately, pets can maintain a good quality of life for many months to years. Our team at Pet Emergency Clinic and Referral Center would like to educate you on kidney failure, to ensure your pet receives the care they deserve.
Why is my pet’s kidney function important?
The kidneys function in several ways to maintain homeostasis throughout the body.
- Water conservation — To maintain hydration, the kidneys regulate the amount of water removed, based on water intake. If your pet is dehydrated, the kidney must respond by conserving water, meaning they must remove waste products using the smallest water volume possible. If your pet drinks too much water, the kidneys must respond by removing the water to prevent blood dilution. If your pet has insufficient kidney function, they will not be able to make concentrated urine, and they will need to drink extra water to process their waste products. This is why excessive water intake is an important early warning sign in pets affected by kidney failure.
- Toxin removal — The kidneys filter out metabolic wastes. If circulation through the kidneys is insufficient, or the damaged kidneys cannot handle the waste load, toxins will accumulate. When the toxins in the bloodstream exceed the normal range, the condition is called azotemia. When the toxins reach a point where they cause your pet to feel sick, the condition is called uremia. Keeping the toxins below the uremic level will help ensure your pet has a good quality of life.
- Electrolyte balance — The kidneys control the balance between calcium and phosphorus, and sodium and potassium. When kidney function is impaired, phosphorus levels rise and potassium levels fall, leading to weakness.
- Blood pressure regulation — Sensors in the kidney help regulate blood pressure in the body. When these are damaged, high blood pressure can result, causing further kidney damage.
- Protein conservation — The kidneys’ filtration system typically retains proteins while removing harmful wastes. When this system is damaged, significant protein can be lost.
- pH balance — The body’s metabolic processes require a narrow pH range for efficiency. The kidneys regulate this balance.
- Red blood cell production — The kidneys produce erythropoietin, a hormone that signals the bone marrow to make more red blood cells. When the damaged kidney does not make this hormone, anemia occurs.
What is the difference between acute and chronic kidney failure in pets?
Kidney failure is typically classified as acute or chronic disease, and staged from I to IV. Stage I pets are mildly affected, and stage IV pets are severely affected.
- Acute kidney failure — Acute kidney failure is the result of sudden injury causing insufficient kidney function. The most common causes include decreased blood supply, toxins, heart failure, infection, urinary tract obstruction, sepsis, and cancer. Signs usually manifest in less than a week, and can occur minutes to hours after toxin ingestion. Signs include increased water intake and urination, abdominal pain, lethargy, vomiting, diarrhea, and seizures. As the condition progresses, your pet may stop urinating completely.
- Chronic kidney failure — Pets affected by chronic kidney failure gradually lose kidney function. This issue is more common in older pets, and prevalence increases as your pet ages. Signs include increased thirst and urination, lethargy, decreased appetite, vomiting, diarrhea, and weight loss.
How is kidney failure in pets managed?
Early, aggressive treatment is required to treat acute kidney failure. Hospitalization to administer intravenous fluids is often required, and the causative agent, if known, is addressed. Some pets who experience acute renal failure can be stabilized, but then develop chronic kidney disease. Managing chronic kidney disease involves:
- Underlying cause — If known, the causative agent is addressed (e.g., infections can be treated using antibiotics).
- Hydration — Correcting dehydration is paramount in all kidney patients. Increased urination, vomiting, diarrhea, and decreased appetite all contribute to dehydration. Intravenous fluids may be needed to stabilize a pet, and subcutaneous fluids may be required to maintain their hydration. Feeding wet food, or adding water to dry food, can help increase water intake. Offering numerous water bowls, and cleaning the bowls daily, can also encourage water consumption.
- Energy requirements — Pets affected by kidney failure typically have poor appetites. They need to consume sufficient calories to prevent fat and muscle loss, and meet their daily energy requirements. You can offer your pet several options to see which food they prefer. Higher fat diets are often recommended for pets in kidney failure, because they are more palatable and energy dense. Several small meals a day can help pets get the nutrients they need, and minimize nausea.
- Renal diets — Diets are available that have been specifically formulated for pets affected by impaired kidney function. These diets restrict phosphorus, phosphate, and acid. In later stages, your veterinarian may also recommend restricting protein. These diets provide adequate nutrition, while reducing the work the kidneys need to perform.
If your pet is affected by kidney failure, their condition can be managed to slow the disease progression and keep your pet feeling well. Our internal medicine team will be happy to determine an appropriate management plan for your pet. If your veterinarian believes a referral is in their best interest, contact our team at Pet Emergency Clinic and Referral Center, to receive emergency care.