Pathogenesis and treatment of dialysis hypotension

Dialysis-induced hypotension (DIH) is a very serious clinical problem. It is one of the most frequent complication in renal replacement therapy which diminish patient's quality of life, and increases mortality in the dialyzed population. The main mechanism of DIH is rapid reduction of blood volume owing to ultrafiltration and decrease in extracellular osmolarity during the dialysis session. Coexisting illnesses, especially cardiovascular diseases, particularly common in older and diabetic patients have an essential meaning in the episodes of dialytic hypotension. Efficient treatment of DIH is difficult owing to no generally accepted guidelines – is still a great challenge to the nephrologist. Multilevel strategy of DIH management includes emergency replacement of intravascular volume in acute episodes of hypotonia, accurate assessment of ‘dry weight', education of the patient, adequate hypertension treatment, and assessment methods strictly related to hemodialysis procedure such as low dialysate temperature, longer dialysis sessions or daily dialysis, sodium profiling or application of the modern dialysis technique as biofeedback equipment. There is also a possibility for pharmacological treatment with the use of such agents – as the well described midodrine, or other drugs such as caffeine, effedrin, and vasopressin analogs. The new class of drugs which can be a novel therapeutic option for DIH treatment are adenosine receptor antagonists and selective inhibitors of the inducible form of nitric oxide synthase. Besides the discussed strategies, efficient treatment of congestive heart failure, a common reason of hypotension in uremic patients, should not be overlooked.