Hemodialysis Modalities and Clinical Applications

Introduction to Hemodialysis

The standard treatment for patients with end-stage renal disease (ESRD) is conventional intermittent hemodialysis (3 times a week, 3-4 hours per session), while prolonged modalities (continuous or intermittent prolonged renal replacement therapy) are preferred for critically ill patients with acute kidney injury (AKI) and hemodynamic instability 1, 2, 3

Intermittent hemodialysis is the most commonly used extracorporeal modality for patients with chronic kidney disease in the terminal stage, typically performed 3 times a week during 3-4 hours per session 1, 2
Hemofiltration is utilized in patients prone to hypotension during chronic renal replacement therapy, with solute removal achieved by convection instead of diffusion 2
Hemodiafiltration combines diffusion and convection in the same treatment, frequently combined with hemodialysis in the same session 2, 3

Continuous renal replacement therapy (CRRT) is the preferred modality for critically ill patients with AKI and hemodynamic instability, with a duration of 24 hours a day 2, 3
Prolonged intermittent renal replacement therapy (PIRRT) is a "hybrid" therapy combining characteristics of intermittent and continuous modalities, with a duration of 8-12 hours per day 2, 3

For patients with stable end-stage renal disease (ESRD), conventional intermittent hemodialysis is the first-line treatment (3 times/week, 3-4 hours) 1, 2
For critically ill patients with AKI, evaluate hemodynamic status first: if hemodynamically stable, intermittent hemodialysis is acceptable; if unstable, CRRT or PIRRT are preferred 2, 3

The evidence supporting different modalities is generally of very low quality, with most recommendations being conditional 4