Dialysis is one of the renal replacement therapy methods, the purpose of removing metabolites and toxins through hemodialysis and maintaining the stability of water-electrolyte balance and acid-base balance. The indications include: 1, chronic renal failure requiring dialysis to maintain life; 2, acute renal failure to help renal function recovery through dialysis; 3, metabolic diseases, such as ketoacidosis and metabolic acidosis; 4, acute left heart failure due to volume overload and refractory hypertension; 5, electrolyte disorders, such as hyperkalemia, hypercalcemia, hypocalcemia and hyperphosphatemia, which can also be 6. Renal insufficiency or normal renal function after poisoning by various drugs or toxins also requires hemodialysis; 7. Acute necrotizing pancreatitis, sepsis, etc.