Downloaded 57 times
![PHARMACOLOGICAL MEASURES
• Unfractionated or low molecular weight heparins
• Unfractionated heparin (UFH) [5-30kDa] is the most
commonly used anticoagulant
• typical regime involves a 40-70 IU.kg-1 bolus followed by
a pre-filterinfusion at 5-10 IU.kg.-1hr-1
• It is the most cost effective anticoagulant and is fully
reversible with protamine.](https://image.slidesharecdn.com/rrt-dr-170307041157/85/Rrt-dr-sarmistha-14-320.jpg)
![• Low molecular weight heparins (LMWH) [4.5-6kDa]
• They are dependant on renal elimination so in this
setting their dosing needs to be guided by anti-factor Xa
levels (aiming for 0.25-0.35 IU.ml-1
• The half life of LMWHs is longer than for UFH (2-6 hrs
versus 1.5-3hrs) and their effect can only be partially
reversed with protamine.](https://image.slidesharecdn.com/rrt-dr-170307041157/85/Rrt-dr-sarmistha-15-320.jpg)
![PHARMACOLOGICAL MEASURES
• Unfractionated or low molecular weight heparins
• Unfractionated heparin (UFH) [5-30kDa] is the most
commonly used anticoagulant
• typical regime involves a 40-70 IU.kg-1 bolus followed by
a pre-filterinfusion at 5-10 IU.kg.-1hr-1
• It is the most cost effective anticoagulant and is fully
reversible with protamine.](https://image.slidesharecdn.com/rrt-dr-170307041157/75/Rrt-dr-sarmistha-14-2048.jpg)
![• Low molecular weight heparins (LMWH) [4.5-6kDa]
• They are dependant on renal elimination so in this
setting their dosing needs to be guided by anti-factor Xa
levels (aiming for 0.25-0.35 IU.ml-1
• The half life of LMWHs is longer than for UFH (2-6 hrs
versus 1.5-3hrs) and their effect can only be partially
reversed with protamine.](https://image.slidesharecdn.com/rrt-dr-170307041157/75/Rrt-dr-sarmistha-15-2048.jpg)
More Related Content
Rrt dr.sarmistha
- 1.
- 2. Definition : • Renalreplacement therapy is a term used to encompass life- supporting treatments for renal failure. • It includes a variety of treatment modalities.
- 3. Modality of RRT •Intermittent hemodialysis (IHD) • Continuous renal replacement therapy (CRRT) • Hybrid therapies, like SLED • Peritoneal dialysis
- 4.
- 5. Indications- • Acute kidneyinjury • Chronic renal failure /ESRD with following complications: i)severe hyperkalemia- >6.5 meq/l not responding to medical treatment ii)fluid overload/ pulmonary oedema, anasarca iii)severe metabolic acidosis pH-<7.10 iv)UOP< 200ml/12hrs v)uremia i.e, BUN >80mg/dl or s.creatinine > 4mg/dl vi)severe dysnatremia- Na <115 meq/l or 160 meq/l vii)uremic pericarditis/encephalopathy viii)hyperthermia>40 deg C
- 6. Principles of dialysis •diffusion = passive movement of solutes across a semi-permeable membrane down concentration gradient – Good for small molecules • convection = solute + fluid removal across semi-permeable membrane down a pressure gradient (solvent drag) – Better for removal of fluid and medium-size molecules
- 7. Principles of dialysis •Miller'sAnesthesia, 7th ed. 2009 •Foot. Current Anaesthesia and Critical Care 2005; 16:321-329 Hemodialysis = solute passively diffuses down concentration gradient Dialysate flows countercurrent to blood flow. Urea, creatinine, K move from blood to dialysate Ca and bicarb move from dialysate to blood. Hemofiltration: uses hydrostatic pressure gradient to induce filtration / convection plasma water + solutes across membrane. Hemodiafiltration: combination of dialysis and filtration.
- 8. Hemo dialysis : •The 3 essential components of HD are : Dialyzer Composition of dialysate Blood delivery system DIALYZERDIALYZER :: • Hollow-fiber dialyzer, the most commonly used type of dialyzer, is composed of bundles of capillary tubes through which blood circulates and the dialysate travels on the outside of the fiber bundles. • The blood and the dialysate may circulate in opposite direction
- 9. Dialysis membrane : •It can be synthetic or biological. Cellulose : .has low flux .poor in removing middle MW molecules. . More complement and leucocyte activation.
- 10. • SYNTHETIC : High flux membranes. Made up of Polyamide, Polysulphone (PS). Allows removal of middle MW substances.
- 11.
- 12. Access location AV FISTULAAV GRAFT
- 13. Vascular access inHD/CRRT Site Advantages disadvantages IJV Straight access Swings in flow associated with respiration. Subclavian Least association with infection. Swings in flow as above. Risks of pneumothorax Femoral Ease of access Infection rates high.
- 14. PHARMACOLOGICAL MEASURES • Unfractionatedor low molecular weight heparins • Unfractionated heparin (UFH) [5-30kDa] is the most commonly used anticoagulant • typical regime involves a 40-70 IU.kg-1 bolus followed by a pre-filterinfusion at 5-10 IU.kg.-1hr-1 • It is the most cost effective anticoagulant and is fully reversible with protamine.
- 15. • Low molecularweight heparins (LMWH) [4.5-6kDa] • They are dependant on renal elimination so in this setting their dosing needs to be guided by anti-factor Xa levels (aiming for 0.25-0.35 IU.ml-1 • The half life of LMWHs is longer than for UFH (2-6 hrs versus 1.5-3hrs) and their effect can only be partially reversed with protamine.
- 16. GUIDELINES FOR NO ANTICOAGULATION •INR> 2-2.5 • APTT > 60 seconds • platelet count < 60 x 10³.mm3
- 17. Prostaglandins Prostaglandins (prostacyclin orprostaglandin E2) inhibit platelet function and can either be used on their own or in combination with heparin ,they have a synergistic effect. short half life ,administered as an infusion 4-8ng/kg/hr anticoagulant effect stops within 2 hours of discontinuing the infusion The main side effect is vasodilation
- 18. Regional citrate anticoagulation •It is alternative to heparin • Sodium citrate is infused into the circuit pre-filter which chelates calcium and inhibits clot formation.
- 19. Intermittent hemodialysis • Diffusiveprocess • Movement of solutes occur along an electrochemical gradient • A low permeability cellulose base membrane is employed • Dialysate sol flows countercurrent to blood flow • Smaller molecules are removed efficiently • Solute removal is proportionate to dialysate n blood flow rate Qb- 150-300ml/min, Qd- 300-500ml/min • Typically performed 4hrs thrice weekly or daily
- 20. IALYSIS DOSE MEASUREMENT/ ADEQUACYIALYSIS DOSE MEASUREMENT / ADEQUACY : • UREA REDUCTION RATIO : URR = Pre dialysis BUN – Post dialysis BUN * 100 Pre dialysis BUN Ideally it should be >65% • Single pool urea kinetics : = K T v k = clearance of urea in ml/min t = time of dialysis in hrs V = vol of distribution Ideally it should be above 1.3
- 21. advantages disadvantages Relatively inexpensive Rapidcorrection of acidosis Rapid correction of fluid overload Minimizes anticoagulant exposure Mobility possible Cannot be used in hemodynamically unstable pts( i.e. shock)
- 22. Continous Renal replacementtherapy
- 23. SLOW CONTINUOUS ULTRAFILTRATION (SCUF): • Qb-100-250ml/min, Quf- 5-15ml/min • No fluids are administered either as dialysate or replacement fluids. • Indicated in CCF refractory to diuretics and in volume overload.
- 24. CONTINUOUS VENO-VENOUS HEMOFILTRATIONCONTINUOUSVENO-VENOUS HEMOFILTRATION (CVVHF)(CVVHF) :: • Solute clearance occurs by convection. • No dialysate , Qb-100-250ml/min,Quf-15-60ml/min • Replacement fluid provided to replace the excess volume that is being removed and replenish desired solutes. • Effective method of solute removal. • Major advantage is that solute can be removed in large quantities
- 25. CONTINUOUS VENO-VENOUS HEMODIALYSISCONTINUOUSVENO-VENOUS HEMODIALYSIS (CVVHD)(CVVHD) : • blood is driven through a low permeability dialyzer • Qb= 100-250ml/min, Qd= 15-60ml/min, Quf= 1-8ml/min • Solute clearance is mainly diffusive, and efficiency is limited to small solutes only.
- 26. CONTINUOUS VENO-VENOUS HEMODIAFILTRATION (CVVHDF): • blood is driven through a highly permeable dialyzer • A replacement solution is needed to maintain fluid balance • Has benefits of both diffusion and convection for solute removal. • Qb=100-250ml/min,Qd=15-60ml/min,Qf=15-60ml/min
- 27. SLOW LOW- EFFICIENCYDIALYSIS : ( SLED )SLOW LOW- EFFICIENCY DIALYSIS : ( SLED ) •Uses dialysate low flow rates & low blood flow rates •Excellent small molecule detoxification. •Reduced anticoagulant requirement. •11 hrs SLED is comparable to 24 hrs of CHD . •Decreased costs compared to CRRT.
- 28. WHICH FORM OFRRT SHOULD WE USE?
- 29. 2. The patient`scardiovascular status• CRRT causes less rapid fluid shifts and is the preferred option if there is any degree of cardiovascular instability. 3. The availability of resources • CRRT is more labour intensive and more expensive than IHD • Availability of equipment may dictate the form of RRT. 4. The clinician`s experience • It is wise to use a form of RRT that is familiar to all the staff involved. 5. Other specific clinical considerations • Convective modes of RRT may be beneficial if the patient has septic shock • CRRT can aid feeding regimes by improving fluid management • CRRT may be associated with better cerebral perfusion in patients with an acute brain injury or fulminant hepatic failure.
- 30. PERITONEAL DIALYSISPERITONEAL DIALYSIS: • In peritoneal dialysis, 1.5 – 3 L of peritoneal dialyzate solution is infused into the peritoneal cavity and allowed to dwell for a set period of time, usually 2 to 4 hours. • The rate of diffusion diminishes with time and eventually stops when equilibration between plasma and dialyzate is reached
- 31. COMPLICATIONSCOMPLICATIONS : • Peritonitis. • Catheter associated infections . • Protein loss . • Interference with diaphragm function . • Residual uremia . • Peritoneal membrane failure.
- 33. Complications common toIHD, CRRT, and hybrid therapies 1.Complications related to the vascath (including line- related sepsis) 2.Haemodynamic instability 3. Air emboli 4. Platelet consumption 5. Blood loss 6. Electrolyte imbalances 7.Hypothermia 8.Effects of anticoagulation (bleeding or specific side-effects of the anticoagulant used e.g. heparin induced thrombocytopenia).
- 34. Dialysis Disequilibrium Syndrome •self-limited condition characterized by nausea, vomiting, headache, altered consciousness, and rarely seizures or coma. • It typically occurs after first dialysis in very uremic patients. • triggered by rapid movement of water into brain cells following development of transient plasma hypo-osmolality as solutes rapidly cleared from bloodstream during dialysis. • incidence has fallen in recent yrs with more gradual institution of dialysis, precise prescription of dialysis to include such variables as membrane size, blood flow rate, and sodium profile.
- 35.
Editor's Notes
- #7 Dialysis is a process which uses diffusion which is… Filtration is a process using convection which is..
- #8 Convective transport of small and middle molecular weight solutes in same direction as water. Usually requires substitution fluid to prevent excess fluid removal. Although the use of pump-driven venovenous circuits increases the technical complexity of therapy, the elimination of the hazards of prolonged arterial cannulation and the provision of higher solute clearances make these the preferred modes of therapy [28]. Theoretically, convective therapies (hemofiltration) provide greater clearance of higher molecular weight solutes than diffusive therapies (hemodialysis); however, no studies have demonstrated an association between the mechanism of solute transport and clinical outcomes.