Put them on the Filter

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Put them on the Filter

• Renal Replacement Therapy in ITU
• Susanne Young
• Aug 04

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content

• Indications for RRT
• Dialysis vs Haemofiltration recap
• Variations in RRT
• What we need to know!

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Indications for RRT

• Uraemia
• Acidosis
• Fluid overload
• Hyperkalaemia
• Pericarditis

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DIALYSIS V FILTRATION
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DIALYSIS

• Aggressive removal of small solutes Ur, Crn, K,
  move down concn gradient
• Ca, HCO3 moves from dialysate to blood
• Fluid removal slower but reduction in solute
  concentration faster
• Replacement fluid not usually given
• More risk arterial embolisation

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FILTRATION

• Removal of fluid
• Filtration itself removes small solutes in
  roughly the same concentrations as plasma
• Removes large solutes
• High flow rates would cause hypovolaemia
• So, admin of (solute poor) substitution fluid
  will reduce solute concentration by dilution.

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Types of RRT

• SCUF- no replacement fluid, dehydrating
• CVVH- replacement solution
• CVVHD- replacement and dialysate soln.
• CVVHDF
• IAVHD

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SCUF
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CVVH
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When are you checking the coag?

• HEPARIN
• lock the lines at insertion (5000iu/ml) or when
  not in use.
• ?Heparin bolus- yes unless contraindicated
  50iu/kg
• Aim for APR 1.5x normal only. Start at
  800-10000iu/hr (1000iu/ml ALWAYS)
• Check at 4hrs then daily

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How much fluid do you want off

• FLUID REMOVAL in CVVH
• Patient Fluid removal rate 10-1000ml/h, (higher
  in SCUF) around 100ml/h ballpark AS PER FLUID
  BALANCE
• Replacement fluid flow rate 100-4500ml/h, (lower
  in HD mode)
• Blood flow 10-180ml/min (120 ususal)
• Check UE at 4hrs

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What bags do you want me to use

• Standard bag composition
• Lactate free if Met Acidosis
• More K if hypokalaemic 2-4mmol/h.
• Now could you fill out the prescription?