Comprehensive analysis of hemodialysis and peritoneal dialysis principles , indications and precautions

Dialysis (dialysis): diffusion through the semipermeable membrane into the water ( or buffer ) of small molecules by the principle of the separation of small molecules and biological macromolecules of a separation and purification techniques.
Dialysis component ( solute or water ) in the treatment of body fluids discharged through the semipermeable membrane in vitro . Commonly used in acute or chronic renal failure, in the case of drugs or other toxins accumulated in the body . Commonly used in dialysis hemodialysis and peritoneal dialysis there .
Hemodialysis
The patient's blood and the dialysis solution while introducing the dialyzer ( opposite to the direction of flow of both ) , use of a dialyzer ( artificial kidney ) a semipermeable membrane , the excessive accumulation of blood toxins and excess water cleared from the body, and supplementary base to correct acidosis, electrolyte imbalance adjustment , replacement kidney excretory function .
Is commonly known as artificial kidney dialysis , hollow fiber type and flat type coil type 3 . The most common is a hollow fiber type, and from 1 to 15,000 hollow fibers, i.e. the walls of the hollow fiber dialysis membrane , a semipermeable membrane properties. Hemodialysis blood flow into each of the hollow fibers , and dialysate flows outwardly through the hollow fibers of each flow direction of blood flow in the opposite direction with the dialysate , removal of toxic principle through a semipermeable membrane , and the permeate by ultrafiltration to remove moisture .
Indications include hemodialysis :
① acute renal failure .
② acute intoxication of drugs or poisons .
③ chronic renal failure.
④ renal function prior to transplant after kidney transplant failure or rejection of renal allografts were nonfunctional .
⑤ other diseases ( hepatic failure , schizophrenia, psoriasis ) .
Hemodialysis relative contraindications include :
① extremely critical condition , hypotension, shock .
② severe infection sepsis .
③ severe myocardial dysfunction or coronary heart disease .
④ After major surgery three days were . ⑤ severe bleeding tendency , cerebral hemorrhage and severe anemia .
⑥ psychiatric substandard author . ⑦ cancer patients .
Usually patients need dialysis three times a week , every 4 to 5 hours. Early initiation of dialysis should be irreversible organ damage and to facilitate the body's metabolism to correct excessive accumulation of toxins caused due when creatinine clearance decreased to 10 ~ 12mL/min when dialysis should begin . Effect of dialysis patients 15 to 60 years old is good and safe , but because of dialysis technology continues to improve and new emerging dialysis equipment , patients over the age of 70 can get good results.
To ensure the quality of life of dialysis patients , improve recovery rates , hemodialysis patients should ensure that the daily protein intake of 1.0 to 1.2 g / kg and 146.3 kJ / kg , taking adequate intake of water-soluble vitamins and trace elements to supplement the dialysis lost volume . The 5-year survival in dialysis patients reported in different countries , about 50 % to 80 %, 10 -year survival rate of over 50% also reported .
Peritoneal dialysis therapy
Is the use of peritoneal dialysis as a semipermeable membrane , into the peritoneal dialysis fluid through the tube to the abdominal cavity , removing toxins through the diffusion theory, correction of electrolyte and acid-base balance disorders, by osmosis principle ( to within plus glucose peritoneal dialysis solution to improve osmotic solution ) ultrafiltration to achieve alternative renal excretory function .
Peritoneal dialysis compared with hemodialysis equipment is simple, can be operated at the bedside , and avoid sudden changes in fluid balance .
Peritoneal dialysis into continuous ambulatory peritoneal dialysis (CAPD, the patient can carry the device freely ) , persistent cycling peritoneal dialysis (CCPD, the advantage with CAPD, nocturnal dialysis dialysis machines rely on the abdominal wall , can still work during the day ) and intermittent peritoneal dialysis ( for acute patients ) . Average daily should be 4 to 6 times dialysis , each poured into 2000mL dialysate . Without relying on peritoneal dialysis machine , easy to operate , no special training of personnel , it is inexpensive, can be carried out in primary health care units .
Although peritoneal dialysis and hemodialysis same indications , but each has pros and cons , you can not replace each other , it should be properly selected according to the primary disease , illness and health , economic condition of the patient , so that patients get the maximum benefit. Priority should be given the following circumstances peritoneal dialysis :
① elderly , persons with poor cardiovascular function .
② hemodialysis vascular access difficulties .
③ severe bleeding tendency can not make those systemic heparin hemodialysis .
④ diabetic nephropathy uremia , they will be joined by intraperitoneal insulin , glucose can control better.
The following cases of peritoneal dialysis Contraindications:
① abdomen three days after major surgery.
② peritoneal adhesions or intestinal obstruction .
③ abdominal infection who can not be cloned into dialysis tubes .
④ abdominal tumors , intestinal fistula, diaphragmatic hernia , etc.

Strict aseptic peritonitis can cause repeated episodes of peritonitis can reduce abdominal area dialysis , dialysis efficacy decline. In addition, because the peritoneal membrane pores on the membrane pore size larger than hemodialysis unit , so the nutrients lost when compared to hemodialysis dialysate from serious . Therefore, strict aseptic technique and adequate nutrition is peritoneal dialysis guarantee of success. Peritoneal dialysis 1,2,3,4,5 -year survival rate was 90 %, 80 %, 70 %, 65 % and 46 %, about 10% annually diminishing , has survived for 20 years has been reported by the world.