indra ppt on Hemodialysis in ckd patient

HEMO

1. HEMODIALYSIS By indra 21 st batch

2. RENAL REPLACEMENT THERAPY Various options of RRT includes Hemodialysis Hemofiltration Hemodiafiltration Peritoneal dialysis Renal transplantation

3. INDICATIONS FOR STARTING RRT IN AKI AND CKD

4. CONTRAINDICATION Absolute
• No vascular access possible
Relative
• Difficult vascular access
• Needle phobia • Cardiac failure • Coagulopathy

5. HEMODIALYSIS Components 1.Dialyzer and membrane 2.Safety monitors 3.Dialysate 4.Blood delivery system 5.Water purification system

6. DIALYZER AND MEMBRANE Dialyzer provides countercurrent transfer of solutes and fluid across a semipermeable membrane. The semipermeable dialysis membrane separates the blood compartment from the dialysate compartment . Most current membranes are made of entirely synthetic materials, such as polyacrylonitrile , polysulfone , polycarbonate, polyamide, and polymethylmethacrylate , and are more biocompatibles than cellulose based.

7. Transport of molecules across the dialysis membrane is driven by (1) the concentration gradient (diffusive transport) (2) the hydrostatic pressure gradient across the membrane (convective transport). In the case of protein-bound solutes, only their free fraction is transported across the membrane, unless so-called albumin-leaky membrane are used.

8. . The flux of solutes is also affected by their charge and the protein concentration on the blood side (Gibbs- Donnan effect)

9. Dialyzer efficiency increases with surface area (usually between 0.8–2.1 m2; smaller dialyzers with surface areas between 0.075–0.245 m2 are used for treatment of neonates). The dialyzer mass transfer area coefcient ( KoA ) for urea is a measure of theoretically maximal possible urea clearance (mL/min). Dialyzer efficiency can be categorized based on KoA for urea as low (<500 mL/min), modera te (500–700 mL/min), and high (>700 mL/min). High flux andmedium cut-off membranes have pores large enough to allow some passage of molecules such as β2- microglobulin (molecular weight 11,800 Da), tumor necrosis factor (TNF)- α (17 kDa ),

10. Water permeability is defined by the ultrafiltration coefficients ( Kuf ) that describes the transmembrane u ltrafiltration volume per hour and unit of hydrostatic transmembrane pressure in millimeters of mercury. In high- flux dialyzers, Kuf can be as high as 80 mL/h/mm Hg. High- flux and medium cut-off membranes demonstrate substantial internal ultrafiltration at the proximal part of the dialyzer and back fi ltration of dialysate into the blood at the distal end of the dialyzer blood compartment.

11. Safety monitors Pressure monitors Between the arterial needle and the blood pump ( prepump pressure): Overly negative values may signal reduced arterial inow and access problems.
Between the blood pump and the dialyzer inlet ( postpump ): A highpressure may signal dialyzer clotting.
Between the dialyzer outlet and the air trap;A high pressure will point towards Obstruction in venous limb.

12. 2.Venous air detectors and air trap are located downstream of the venous pressure gradient
3.venous pressure monitor. A positive signal at the air detector automatically clamps the venous line and stops the blood pump.
4.A blood leak detector is placed in the dialysate outflow line
5. Dialysate temperature is constantly monitored. 6.Dialysis conductivity monitors :monitors concn of ions of dialyzer

13. Dialysate fluid Dialysate is made by mixing two components, which may be provided
as liquid or dry (powder) concentrates . The base concentrate contains sodium bicarbonate and sodium chloride.
The acid concentrate typically contains chloride salts of sodium calcium,magnesium , and potassium, glucose monohydrate, and an organic acid, the latter in the form of acetic acid, citric acid, or lactic acid.
The acid concentrate may contain the salt of an organic acid, such as sodium acetate. The purpose of the acid is to lower the dialysate pH to less than 7.3 so that calcium and magnesium do not precipitate when bicarbonate is added. -Base and acid components are mixed simultaneously with purifed water to make the dialysate.

14. Blood delivery system The blood delivery system is composed of extracorporeal circuit and dialysis acess The blood pump of dalysis machine moves the blood from the acess site through the dialyzer and back to patient. The blood flow rate typically ranges from 250 to 450 ml/ min,depending upon type nad integrity of vascular access. Negative hyrostatic pressure on the dialysate side can be manipulated to achieve desirable ultra filtration.

15. Henodialysis dose The National Kidney Foundation’s KDOQI guidelines recommend a target spKt /V of 1.4 per HD session for patients treated thrice weekly, with a minimum delivered spKt /V of 1.2. In patients with significant residual native kidney function, a lower dose of HD may be appropriate (termed incremental dialysis), provided RKF is measured periodically to avoid inadequate dialysis. For HD schedules other than thrice weekly, a target stdKt /V of 2.1 per week including residual kidney function is recommended

16. Adequacy of dialysis Adequacy of dailysis is measured by fraction removal of urea nirogen and derivatives. Current targets included a urea reduction ratio . i.e fractional reduction in blood urea nitrogen per HD session, of > 65-70% and body water indexed xlearance x time product( kt / V) > 1.2 or 1.05 depending on whether urea concn are equilibrated. For majority of pt with ESRD about 9 to 12 hours of dialysis are required each week usually devided in 3 equal session.

17. Complications Cardiovascular Intradialytic hypotension Intradialytic hypertension Sudden death Cardiac arrythmias Dialysis associated steal syndrome

18. Neuromuscular complications Muscle cramps Restless leg syndrome Dialysis dysequilibrium syndrome Seizure Headache

19. Hematological complications Complement activation and daislysis associated neutropenia Intradialytic hemolysis Hemorrhage Thrombocytopenia Pulmonary complications 1.Dialysis associated hypoxia

20. Others Air embolism 2.Incorrect dialysate compostions leading to electrolyte disbalance ,metabolic abnormalities 3.Dialysis associated anaphylaxis reactions 4.Post dialysis fatigue 5.Pruritus 6.Hearing and vision loss