Mode of Operation
The dialysis machine pumps blood through a vascular access on the patient into dialyzer. Inside the dialyzer, metabolic waste products are separated from the blood. The dialyzer operate as filter that is divided into two parts by a semi permeable membrane. On one side, the patient's blood is pumped fast, on the other side the dialysate flows past.
During the therapy, the dialysate is prepared by the dialysis machine. It consist of prepared water to which certain quantities of electrolyte and bicarbonate, depending on the individual patient's requirements, are added.
During treatment the dialysis machine monitors the blood circulation outside of the body, pumps blood and dialysate in separate circulation systems through the dialyzer and monitors the composition and volume balance of the dialysate.
The heparin pump, which also part of the dialysis machine, adds anticoagulants to the blood so as to prevent the formation of blood clots.
In addition to cleaning the blood, the dialysis machine removes water from the blood, which would be excreted through the kidney in healthy humans.
During isolated ultrafiltration, no dialysate flows through dialyzer. This therapy type serve only for extracting fluid from the patient.
Hemofiltration (HF) is often used with patients suffering from blood circulation problems, for whom this form of therapy is more comfortable.
During the Hemofiltration the blood is predominantly cleaned by convection on the dialyzer membrane. In HF therapy no dialysate is pumped through the dialyzer. Instead, a sterile substitution solution is infused into the blood cycle upstream or downstream of the dialyzer the procedure is called predulution (upstream) or postdilution (downstream).
The filter membrane in the dialyzer has a higher water permeability than a HD filter contains a so-called high-flux membrane (hemofilter) and allows ultrafiltration considerably more fluid than through HD therapy.
The electrolyte concentrations in the substitution solution and in the dialysate identical. The infusion rate is 4-5 l/h. The same volume is ultrafiltered through dialyzer. In this way the so-called convective clearance is increased so that the elimination results are the same as with HD therapy.
During conventional HD therapy, the substitution solution is provided from containing a solution produced under sterile conditions.
The following treatment procedure below not same with the other dialysis type. Beyond that disinfection option necessary after every dialysis, usually recommended citrid acid 50%
Dialysis therapy used RO too, so at Reverse Osmosis installation must be right. UV lamp must closed with ward hemodialysis for more optimal uses from free from bacteria and virus.
Hemodialysis Unit I know used at Indonesia :
- B Braun
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