What Is Renal Failure?

Renal failure is a pathological state in which some or all of the renal function is lost to the advanced stages of chronic kidney disease. Renal failure can be divided into acute renal failure and chronic renal failure. Acute renal failure progresses rapidly, usually due to insufficient blood flow to the kidneys (such as trauma or burns), impaired function of the kidneys due to certain factors, or poisons The injury caused acute kidney failure. The main cause of chronic renal failure is long-term kidney disease. As time progresses and the disease progresses, the function of the kidney gradually declines, leading to the occurrence of renal failure.

Basic Information

English name: renal failure
Visiting department: Nephrology

Common causes: Caused by acute and chronic kidney disease, trauma, poison, etc.
Common symptoms: Manifest oliguria or polyuria, azotemia, uremia-related symptoms

Causes of renal failure

Acute renal failure

Acute renal failure is usually caused by insufficient blood supply to the kidneys (such as trauma or burns), impaired function of the kidneys due to some factors, or injury from poisons.

2. Chronic renal failure

Because of long-term kidney disease, kidney function gradually declines with the progress of time and disease, leading to the occurrence of renal failure.

Classification of renal failure

Acute renal failure

Acute kidney failure progresses rapidly, usually due to insufficient blood supply to the kidneys (such as trauma or burns), kidney blockage due to certain factors, impaired function, or injury from poisons, which causes acute kidney failure.

2. Chronic renal failure

Chronic renal failure refers to a clinical syndrome consisting of slowly progressive renal damage caused by various kidney diseases, which eventually leads to uremia and complete loss of renal function, causing a series of clinical symptoms and metabolic disorders such as biochemical endocrine. The interval from disease to the beginning of renal insufficiency can be from several years to more than ten years.

Clinical manifestations of renal failure

Oliguria

In the most critical stage, the internal environment is severely disturbed. Patients may have oliguria (<400 ml / day) or anuria (<100 ml / day), low specific gravity urine (1.010 1.020), high urinary sodium, hematuria, proteinuria, and cast urine. Severe patients may develop water poisoning, hyperkalemia (often the cause of death during this period), metabolic acidosis (which can promote the occurrence of hyperkalemia), and azotemia (progressive exacerbation can cause uremia), etc., Endangering the lives of patients. This period lasts from a few days to several weeks, and the longer the duration, the worse the prognosis.

2. Polyuria

Urinary volume gradually increases after the oliguria phase. When the daily urine volume exceeds 500 ml, the polyuria phase is entered. Since then, the urine output has increased day by day. The highest urine output is 3000 to 6000 ml per day, and can even reach more than 10,000 ml. At the beginning of the polyuria phase, although urine output increased, renal clearance was still low, and the accumulation of metabolites in the body still existed. After about 4 to 5 days, the serum urea nitrogen and creatinine gradually decrease with the increase of urine volume, and the symptoms of uremia also improve. A large amount of potassium, sodium, chlorine and other electrolytes excreted from urine can cause electrolyte disturbance or dehydration. It should be noted that the peak stage of oliguria may change to hypokalemia. This period lasts 1 to 2 weeks.

3. Recovery period

Urine output gradually returned to normal, and renal function gradually recovered within 3 to 12 months. Most patients recovered to normal levels, and only a few patients turned to chronic renal failure.

Renal failure test

Blood test

Obvious anemia, normal cell anemia, normal or increased white blood cell count. Platelets decrease, and the rate of cell sedimentation increases.

2. Routine urine test

It varies with the primary disease. Their common points are:

(1) The specific gravity of urinary osmotic pressure reduction is low, mostly below 1.018, and it is fixed between 1.010 and 1.012 in severe cases. Nocturnal urine volume is greater than the daily urine volume in the urine concentration and dilution test. The urine specific gravity exceeds 1.020 each time. The difference in urine specific gravity is less than 0.008.

(2) The urine output is reduced below 1000 ml per day.

(3) Quantitative increase of urinary protein In the late stage, because most of the glomeruli have been damaged, urinary protein has decreased.

(4) Examination of urine sediment How many different types of red blood cells, white blood cells, epithelial cells, and granular casts are possible, waxy casts are the most significant.

3. Renal function test

All indicators suggest renal dysfunction.

4. Blood biochemical examination

Plasma albumin is reduced, blood calcium is low, blood phosphorus is increased, and blood potassium and blood sodium depend on the condition.

5. Other inspections

X-ray urinary plain film and radiography, isotope nephrogram, kidney scan, renal biopsy, etc. are helpful for the diagnosis of the cause.

Renal failure treatment

Cause treatment

Treatment for the causes of renal failure, such as insufficient blood supply or blood loss, will provide patients with lost body fluids and water; if there is an infection, anti-infective treatment should be given.

2. Kidney function

Because the kidney has lost its function, the doctor will temporarily use dialysis treatment (commonly known as dialysis) to help remove toxins and waste from the body; if the patient with acute renal failure does not receive appropriate treatment or cannot be controlled, the disease will evolve from acute to In chronic renal failure, life-long dialysis is necessary due to uremia.

Dialysis refers to the selective removal of certain substances from the blood by filtration. In other words, the toxic waste, water and salt accumulated in the patient's body after renal failure are eliminated by artificial means, so that the patient's physical condition is restored to a healthy state. There are currently two forms of dialysis: hemodialysis and peritoneal dialysis. Hemodialysis replaces the function of the kidneys with a special machine. Peritoneal dialysis uses the human peritoneum as a filter to remove toxins from the body.

3. Diet

Diet control. For patients with renal failure, due to the destruction of renal function, the toxins and wastes produced by food after being eaten into the body cannot be excreted normally. Therefore, special attention must be paid to the diet to avoid causing physical burden. .

4. Kidney transplant treatment

Some patients with end-stage renal failure need long-term dialysis treatment. When the patient's own conditions are suitable, kidney transplantation (renal replacement) can bring a better quality of life to the patient; but kidney replacement is a major project. Although current medical technology has Quite well, there is still a lot of pre-evaluation needed to improve the chance of a successful kidney replacement.

Kidney transplantation is the process of transplanting the kidneys of organ donors into patients undergoing transplantation through surgery. Possible sources of kidney: family members, spouses, close friends, or brain-dead people who have signed an agreement to donate organs during their lifetime. Of course, the best-matching kidneys usually come from the siblings of the recipient because their genetic fit is most likely.

Kidney transplantation is currently the best way to treat kidney failure, because the kidney transplanted into the patient can almost completely replace the failed kidney function and allow the patient to lead a normal life.