The functions of the kidney are divided into four:
- Purify the blood of waste products generated by the body.
- Maintain a neutral balance between water and electrolytes by adjusting the composition of the urine.
- To produce bicarbonate.
- Production of the hormones erythropoietin, renin and vitamin D.
It should be noted that the main function of the kidneys is to maintain body homeostasis. Urine production is only a by-product of the kidneys.
Chronic kidney disease
Chronic kidney disease (CKD) is a public health problem given its high frequency and significance. It occurs when the glomerular filtration rate is less than 60 ml per minute and lasts for more than three months.
The most frequent cause is diabetes mellitus, followed by arterial hypertension. Symptomatology is very varied. This includes arterial hypertension and heart failure, bone-mineral metabolism disorders, anemia, digestive disorders or accumulation of potassium and acids.
As treatment it is recommended to reduce salt in meals, regulate arterial hypertension and anemia, control proteinuria with inhibitors of the renin-angiotensin aldosterone system and treatment of bone-mineral metabolism disorders.
In cases where the filtration rate is less than 10 ml/min, dialysis or renal transplantation will be required.
Risk factors
- Tobacco
- Arterial hypertension
- Poor control of glucose metabolism
- Presence of albumin in the urine
- Nephrotoxic drugs
- Alteration of lipid profile
- Obesity
- Cardiovascular diseases
Therefore, it is necessary to optimize these factors in order to have a better prognosis of chronic kidney disease.
Arterial hypertension
About 75% of patients diagnosed with chronic kidney disease present problems of arterial hypertension, which is both a cause and a consequence of the disease.
Therapeutic guidelines recommend maintaining blood pressure control, since it allows management of the course of chronic kidney disease. The blood pressure target recommended for patients with CKD, without albuminuria, is 30 mg/24 hours.
For the latter type of patient, treatment with an angiotensin-converting enzyme inhibitor or receptor blocker is recommended. Also for those patients, with or without diabetes, and with urinary albumin secretion levels of > 300 mg/24 hours or glomerular filtration rate of less than 60.
When patients with chronic kidney disease undergo treatment with renin-angiotensin aldosterone system (RAAS) inhibitors, they become prone to develop hyperkalemia or reduced glomerular filtration rate. Because of this, monitor serum potassium and glomerular filtration rate for several weeks after initiating or increasing the dose of any of the drugs.
In cases where hyperkalemia occurs, therapeutic strategies will be aimed at identifying and restricting potassium in the diet. Thus, treatment of metabolic acidosis will be appropriate, as well as initiating a diuretic to increase urinary potassium excretion. Only if the above interventions fail should RAAS treatment be discontinued.