Kidneys perform an essential function of filtering out toxins from the bloodstream. Kidneys are essentially made up of millions of tiny structures named nephrons, which act as filters for the kidney. Certain diseases such as diabetes, cancer or other medical ailments hamper the functioning of nephrons, thereby reducing the ability of kidneys to filter out toxins. This leads to build up of toxins in the body, which warrants immediate treatment. If this condition goes untreated, the resultant build up may lead to coma and eventually death of a person. Usually, dialysis is often recommended as a treatment option in end stage kidney disease.
When is Dialysis Necessary?
When kidney disease reaches an end stage, kidneys lose about 85-90% of their efficiency. Kidneys cannot remove toxins from the body with such reduced level of efficiency. At this stage, only dialysis can help the patient to survive. It is a process of removing toxins from the body using an external device. In short, it mimics the function of kidneys to some extent. It can be done using two methods - hemodialysis and peritoneal dialysis. In hemodialysis, a tube is connected to the arteries, which takes the blood for purification to the dialysis machine. In the machine, a dialysis membrane is present, which removes the toxins from the blood and returns the purified blood. This blood is flown back in the body through a tube connected to the veins.
In peritoneal kidney dialysis process, a solution is flushed through the body to remove toxins. Your abdominal cavity is filled with this special solution, which is then passed to flush the intestines. Toxins and wastes get accumulated in this solution, which is then removed from the abdominal cavity using pumps. Both these techniques can increase the life span of the kidney patient and improve his/her quality of life to some extent. However, none of these techniques can truly replace a kidney.
Only kidney transplant can truly treat a patient with kidney disease. However, the wait for kidney transplant is too long, from a few weeks to several months or even years. During this time, a patient can immensely benefit from the procedure. Besides, in certain patients suffering from heart failure or cancer, kidney transplant is not a feasible solution. In all such circumstances, dialysis may be the only treatment option.
Threshold Conditions for Starting Dialysis
Dialysis is not the cure for kidney disease, but the purpose of this procedure is only to aid in removing wastes from the body. In people suffering from acute renal failure, dialysis is only required until the kidney function improves. However, people suffering from chronic kidney disease may have to be put on dialysis for the rest of their lives or until they receive a transplant.
There are certain threshold conditions, which determine the necessity for dialysis. These conditions are as follows -
- Oliguria (when urine output is less than 200 mL/12 h)
- Anuria/extreme oliguria (when urine output is less than 50 mL/12 h)
- Severe dysnatremia (sodium levels more than 160 mEq/L)
- Hyperkalemia (potassium levels are more than 6.5 mEq/L)
- Severe acidemia (acidic urine with pH less than 7.1)
- Azotemia (level of urea greater than 30 mg/dL)
- Edema to a vital organ (especially pulmonary edema)
- Uremic encephalopathy
- Uremic pericarditis
- Uremic neuropathy/myopathy
- Drug overdose with dialyzable toxin
Side Effects of Dialysis
As mentioned above, dialysis is not a replacement for a kidney. The kidneys perform several other functions apart from removing toxins. One such important function is production of the hormone erythropoietin, which is responsible for the production of RBCs. It cannot be implemented for these other functions. Besides, it is not entirely a safe practice as there are some side effects of kidney dialysis. It carries certain risks, such as that of infection. Also, the process which stretches to about 3 to 7 hours, several times over a week, can be overwhelming for patients.
There is no doubt that dialysis improves the life span of a patient to a great extent. The inconvenience caused due to it can be minimized by certain advanced techniques as well as home dialysis.