Purpose of dialysis-
- To remove waste product and excessive fluid from blood.
- To maintain blood pH and electrolyte balance in blood.
TYPES OF DIALYSIS - There are 2 methods to done dialysis.
- Hemodialysis
- Peritoneal dialysis
- HEMODIALYSIS-
- As the name, hemodialysis, it done directly in blood, by the help of a machine. Its done outside of the body for this procedure a DLC ( dialysis cannula) is inserted in patients right or left juglar vein and varrient shunt is used.
- A dialyze is used in hemodialysis.
- Each time, the artificial kidney( dialyzer) is used for about 6 hours.
- Into dialyzer blood pump at the rate of 200 to 500ml/minute and dialysate flow into opposite direction at the rate of 300 to 900ml/minute.
- Heparine is used as anti-coagulate to prevent clotting into extracorporeal circuits.
- Vital signs are checked and documented every 15 to 30 minutes to detect possible complicastion.
Hemodialysis works on 2 principles-
- Diffusion- Through diffusion particles move from area of greater concentration to area of less concentration through semipermeable membrane such as waste products ( urea, uric acid, creatinine) from blood to dialysate.
- Osmosis and ultra-filtration- Movement of fluid across a semi permeable membrane from area of lesser concentration of particles to area of greater concentration of particles.
Complication of heamodialysis-
- Disequilibrium syndrome- Rapid removal of waste products from blood are faster than CSF, so causes cerebral edema than can cause Hypotention.
- Dialysis encephalopathy-
- Air embolism - Introduction of air into circulatory system.
Accesses for heamodialysis-
- External Arterio-venous shunt (rarely used)
- Mostly commonly used redial artery & basilic vein for shunt formation by silastic tubing.
- Used subclavian catheter for acute dialysis( DLC)
- Internal Arterio-venous fistula-
- Fistula is usually formed between an artery( radial or ulnar) and a vein ( cephalic).
- In this fistula 'arterial steal syndrome' can develop due to excess diversion of blood to vein the arterial perfusion to the hand is compromised.
- Internal Arteio-venous graft-
- A graft of artificial material( Teflon) is used to form bridge between brachial artery and antecubital vein.
- In this type of dialysis peritoneal membrane is used as the filter, because it is the largest serous membrane of the body and its semipermiability.
- Peritoneal dialysis workes on principal of duffusion and osmosis
- Peritoneal dialysis done in 3 steps Fill- Dwell- Drain.
- Fill - 1-2 liter dialysate in 10-20 min
- Dwell- 20 min to 8 hour.
- Drain - Drain out from body
- Peritoneal cavity has rich supply of blood through capillaries so waste products diffuse from blood to dialysate present inside the peritoneal cavity.
- The prefered insertion site for catheter is 3-5 cm below the umbilicus.
- If there is insufficient outflow of dialysate check the kinks or clot in the tubing, change the position of client,ensure catheters position and keep the drain beg below the client's abdomen.
- And give side to side position, head up, and apply mannual pressure on lower abdomen.
CONTRA-INDICATION- Peritonitis, Recent abdominal surgery, respiratory disese.
COMPLICATION-
- Peritonitis (S/S are cloudy outflow, rebound abdomen tenderness, and pain)
- Abdominal pain due to peritoneal irritation, subside after 1-2 week
- Abnormal outflow indicate complication
- Bloody outflow after few exchanges: Vascular complication
- Brown outflow: Bowel perforation
- Urine color outflow: Bladder perforation
- Cloudy outflow: peritonitis