What is the difference between uremic hemodialysis and hemoperfusion?

Hemodialysis is mainly based on the principle of membrane balance, the patient's blood and certain components of dialysate are introduced into the dialyzer together, through the transmembrane movement of semipermeable membrane can quickly remove potassium, correct acidosis; hemofiltration can improve the patient's nutritional indicators, and has a very high toxin clearance rate; hemoperfusion with extracorporeal circulation, the patient's body non-specific adsorption of toxins, drugs removed.