Nephrology

It's important to remember that if the body's filters become clogged, molecules will accumulate in the blood and cause symptoms. In cases of advanced kidney failure, the main molecules responsible for symptoms are:

• Sodium , the mineral in table salt, is in crystalline form. Once in the bloodstream, salt dissolves and does not return to its crystalline form. If the kidneys are no longer able to eliminate ingested salt, it will be stored and retain water with it. This will cause various symptoms such as high blood pressure , edema , weight gain , and unusual shortness of breath , especially when lying down. In cases of excessive sodium and water retention, respiratory distress related to acute pulmonary edema can occur, requiring emergency hospitalization.
• Potassiumis a molecule involved in nerve conduction, enabling muscle contraction. Its accumulation in the blood can block this muscle contraction. This results in a loss of muscle strength, which may manifest as an inability to stand, but more importantly, it can block the contraction of the heart muscle, leading tocardiac arrest in severe cases. High blood potassium levels require emergency hospitalization.
• Uremic toxins represent all the cellular waste produced by the body every day. Their accumulation can cause itching, excessive fatigue, loss of appetite , and weight loss. This is known as uremic syndrome, where the body draws on its reserves until they are depleted.
• Medications, since some are primarily eliminated through urine, can accumulate in the urine, causing symptoms of overdose. Pain relievers (except paracetamol), sleeping pills, some antidiabetic medications, and some antibiotics are particularly susceptible.

Dialysis is an extrarenal purification treatment where toxins are removed through contact between the patient's blood and a fluid called dialysate. The toxins pass from the blood to the dialysate via a membrane. This exchange can be achieved using two techniques:

1. Hemodialysis. With this technique, the exchange between the blood and the dialysate takes place via an extracorporeal circuit. Blood leaves the body to be purified in a machine, then returns to the body. This dialysis method can be performed independently at home or in a hemodialysis center, day or night. To perform hemodialysis, it is necessary to create an arteriovenous fistula or to insert a dialysis catheter in the neck.
2. Peritoneal dialysis. With this technique, the exchange between the blood and the dialysate takes place within the body. The dialysate is infused into the abdomen using a catheter, where it absorbs toxins from the blood, and is then drained out of the abdomen. This dialysis method is performed at home, day or night. A peritoneal dialysis catheter is required to perform this procedure.