Acute Kidney Failure: A Dangerous Complication That Must Be Monitored, Untreated Cases May Result in Death
In this condition, the kidneys rapidly lose their function. Acute kidney failure can be divided into 2 stages. The first stage is the Pre-renal stage, which means kidney failure caused by reduced blood flow to the kidneys, such as in cases of blood loss or shock, leading to a significant decrease in the ability to excrete waste. Patients of this type will have reduced urine output, but since there is no damage to the renal tubular cells yet, if treated with adequate fluid replacement and correction of the reduced blood flow to the kidneys, the kidneys will return to normal within just 24-72 hours, and urine output will return to normal. However, if treatment is delayed, tubular damage will occur, which is called the Acute Tubular Necrosis (ATN) stage. Even with fluid replacement, urine output cannot be increased, and the kidneys cannot return to normal in the short term. But if treated well and the kidney damage is not severe, recovery to normal may occur within about 1 week to 3 months. If it exceeds 3 months without improvement, it is considered chronic kidney failure. However, with proper treatment, the kidneys may return to normal within about 3 days.
Common Causes of Acute Kidney Failure
Severe dehydration causing reduced blood flow to the kidneys, such as severe diarrhea or in trauma patients with massive blood loss; use of drugs or toxins harmful to the kidneys. Common drugs include antibiotics and anti-inflammatory drugs. Generally, long-term medication use may affect the kidneys because almost all drugs are metabolized by the liver and excreted by the kidneys. Severe infections, major surgeries especially heart surgery, kidney inflammation from SLE, or post-infection; urinary tract obstruction from kidney stones in the ureters or bladder, enlarged prostate, or cervical cancer, etc.
Treatment of Acute Kidney Failure
Once acute kidney failure occurs, the treatment steps are as follows:
1. Treat the Cause of Acute Kidney Failure
The important step is to identify and stop the cause as much as possible, such as correcting shock or stopping drugs that may cause acute kidney failure, especially NSAIDs, herbal medicines, and possibly providing fluid replacement if the body is dehydrated.
2. Medication for Acute Kidney Failure
There have been attempts to use various drugs to treat acute kidney failure to improve kidney function or at least increase urine output. Many drugs tested in acute kidney failure are mainly vasoactive agents and diuretics. Although many drugs have shown benefits in animal models, they are mostly effective in prevention. Only a few drugs show therapeutic effects once acute kidney failure has occurred. Unfortunately, despite good results in animal studies, clinical outcomes in patients have not been as effective. Therefore, there is no definitive effective drug treatment for acute kidney failure. Prevention remains the most important.
3. Supportive Treatment and Management of Complications
If the kidneys do not recover after treating the cause and correcting the prerenal condition, and after trying medications as in point 2, the next step is supportive treatment to prevent and manage complications that may occur while waiting for kidney recovery to reduce the need for dialysis, including:
3.1. Control of Fluid Balance The amount of fluid a patient should receive daily should equal the total urine output plus (Insensible loss – water of metabolism = 500-600 ml/day) and extrarenal loss. If the patient’s weight can be measured, the weight should decrease by about 0.2-0.3 kilograms per day. If the weight remains the same or increases, it indicates fluid retention.
3.2 Avoid Nephrotoxic Drugs
3.3 Use of Medications Dosages must be adjusted appropriately according to the reduced kidney function.
3.4 Correct Acidosis by administering alkaline substances in cases of severe acidosis.
3.5 The attending physician must carefully prevent and manage electrolyte imbalances such as hyperkalemia, which is common especially in patients with low urine output. Serum potassium levels should be monitored regularly. Patients prone to high serum potassium should avoid fruits and foods high in potassium and be cautious with fluids containing potassium. If serum potassium is very high or if cardiac complications occur, urgent treatment is necessary as it can be life-threatening.
4. Nutrition in Patients with Acute Kidney Failure
Malnutrition is common in patients with acute kidney failure.
Causes of Malnutrition in Patients
It may result from diseases associated with acute kidney failure or from inadequate food intake. Malnutrition is a significant factor affecting survival and the occurrence of complications in acute kidney failure patients, such as reduced immunity to infections. However, nutritional therapy using various nutrients in acute kidney failure patients remains controversial regarding its effectiveness in reducing mortality and complications, as studies have not reached a definitive conclusion. Therefore, there is no standard guideline for nutritional therapy in acute kidney failure patients. Treatment depends on each institution and varies among patients.
Practical Principles for Nutritional Support Can Be Summarized as Follows:
4.1 Energy
Patients with acute kidney failure should receive about 25-30 kcal/kg per day. For patients with normal gastrointestinal function, oral or gastric tube feeding is preferred because it is convenient, economical, and has fewer side effects. Parenteral nutrition should be used only when enteral feeding is not possible. In patients requiring parenteral nutrition, high concentration glucose (50%) combined with amino acids and fats is often necessary, sometimes requiring central venous administration.
4.2 Amino Acids and Protein
This should be considered based on each patient’s condition. Acute kidney failure patients without clear malnutrition or hypercatabolic state (urea increase not exceeding 20 mg/dL per day and creatinine increase not exceeding 2 mg/dL per day) who have not undergone dialysis and are in the early phase (within 1-2 weeks) should receive low protein intake of 0.6-0.8 g/kg/day, with high biological value protein such as meat, milk, eggs, and fish. However, milk is not recommended due to its high phosphate content, which can accumulate easily in kidney failure patients. If the patient has clear malnutrition, hypercatabolic state, is undergoing dialysis, or has had the disease for more than 1-2 weeks, protein intake should be increased to about 1-1.2 g/kg/day, also with high biological value protein.
4.3 Other Nutrients
Patients with acute kidney failure should receive vitamins and minerals. There is no definitive data on the necessity of vitamin supplementation in acute kidney failure, so formulas similar to those used in chronic kidney failure patients are generally applied. Electrolyte replacement should be adjusted based on laboratory results because the required amounts and excretion vary among patients. Therefore, close monitoring of laboratory tests is necessary to adjust electrolyte supplementation accordingly.
5. Dialysis in Patients with Acute Kidney Failure
Currently, dialysis is considered the standard treatment for acute kidney failure patients who do not respond to supportive care. This treatment helps prevent death. Therefore, all patients with indications for dialysis should receive this treatment, except for those with acute kidney failure associated with cancer or end-stage chronic diseases, and patients with contraindications to dialysis.
