dialysis and replacement solutions for pediatric crrt jordan m. symons, md university of washington...
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Dialysis and Replacement Solutions for Pediatric CRRT
Jordan M. Symons, MD
University of Washington School of Medicine
Children’s Hospital & Regional Medical Center
Seattle, [email protected]
CRRT Solutions:Outline of the Talk
• Purpose of solutions in CRRT
• Goals for a CRRT solution
• Description of solutions currently available for CRRT
• Considerations in choosing a solution for CRRT
Kramer, P, et al. Arteriovenous haemofiltration: A new and simple method for treatment of over-hydrated patients resistant to diuretics. Klin Wochenschr 55:1121-2, 1977.
First CAVH Circuit
CAVH: Good for Fluid Balance,Not So Good for Metabolic Balance
• CAVH removes all molecules slowly– Good for BP stability (slow UF)– Not so good for metabolic control
• Need method to increase molecular clearance without increasing UF rate
Diffusion
• Small molecules diffuse easily
• Larger molecules diffuse slowly
• Dialysate required– Concentration gradient– Faster dialysate flow
increases mass transfer
Convection
• Small/large molecules move equally
• Limit is cut-off size of membrane
• Higher UF rate yields higher convection but risk of hypotension
• May need to Replace excess UF volume
H2O
H2O
H2O
H2O
Neg Press
Solutions in CRRT Address Molecular Control Issues
• Improved mass transfer using diffusion, high-grade convection, or combination– CVVH: a pure convection modality– CVVHD: a diffusion modality– CVVHDF: combined convection/diffusion
• Permits correction of metabolic abnormalities
• Provides “complete” renal replacement
Characteristics of the Ideal CRRT Solution
• Physiological• Reliable• Inexpensive• Easy to prepare• Simple to store• Quick to the bedside• Widely available• Fully compatible
Options for CRRT Solutions
• Peritoneal dialysate:
• Pre-made IV solutions:– Saline, Lactated Ringers
• Multi-bag systems:
• Custom-made solutions:– Local pharmacy; outsource
• Commercially available CRRT solutions
NO
MAYBE
UNNECESSARY
RARELY
Commercial Solutions for CRRT: Several Companies, Multiple Options
• Previously: limited options– No bicarbonate-based solutions– US regulations re: “drug” vs. “device”
• Currently: multiple manufacturers each offering a variety of formulations– Bicarbonate as primary or only base
• The Choice: may depend on local policy, vendors, economic pressures
Normocarb (DSI)
• Bicarbonate buffered
• Concentrate must be compounded
• Final volume 3.24 liters (240ml concentrate added to 3 L bag)
Chemical Content of Normocarb
IonConcentration After
Mixing (mEq/L)
Sodium 140
Potassium 0
Chloride 107
Bicarbonate 35
Calcium 0
Magnesium 1.5
Normocarb HF (DSI)
• Bicarbonate buffered
• Concentrate must be compounded
• Final volume 3.24 liters (240ml concentrate added to 3 L bag)
• 2 ionic formulations– Normocarb HF 25– Normocarb HF 35
Chemical Content of Normocarb HF
Ion (mEq/L) HF 25 HF 35
Sodium 140 140
Potassium 0 0
Chloride 116.5 106.5
Bicarbonate 25 35
Calcium 0 0
Magnesium 1.5 1.5
PrismaSate (Gambro)
• Bicarbonate buffered
• Small amount of lactate
• 5 liter bag
• 2 compartments to prevent precipitation
• Six ionic formulations
Chemical Content of PrismaSateIon (mEq/L) BK0/3.5 BGK2/0 BGK4/0/1.2 BGK4/2.5 B22GK4/0 BK2/0
Sodium 140 140 140 140 140 140
Potassium 0 2 4 4 4 2
Chloride 109.5 108 110.2 113 120.5 108
Bicarb 32 32 32 32 22 32
Lactate 3 3 3 3 3 3
Calcium 3.5 0 0 2.5 0 0
Magnesium 1 1 1.2 1.5 1.5 1
Gluc(mg/dL) 0 110 110 110 110 0
PrismaSol (Gambro)
• Bicarbonate buffered
• Small amount of lactate
• 5 liter bag
• 2 compartments to prevent precipitation
• Seven ionic formulations
Chemical Content of PrismaSol
Ion (mEq/L)BK
0/3.5BGK 2/0
BGK 2/3.5
BGK 4/2.5
BGK 4/0
BGK 0/2.5
BK 0/0
Sodium 140 140 140 140 140 140 140
Potassium 0 2 2 4 4 0 0
Chloride 109.5 108 111.5 113 110.5 109 106.5
Bicarb 32 32 32 32 32 32 32
Lactate 3 3 3 3 3 3 3
Calcium 3.5 0 3.5 2.5 0 2.5 0
Magnesium 1 1 1 1.5 1.5 1.5 1.5
Gluc(mg/dL) 0 100 100 100 100 100 0
Accusol (Baxter)
• Bicarbonate buffered
• No lactate
• 2.5 liter bag
• 2 compartments to prevent precipitation
• Five ionic formulations
Chemical Content of AccusolIon (mEq/L) 5B9248 5B9249 5B9250 5B9251 5B9252
Sodium 140 140 140 140 140
Potassium 4 2 0 2 2
Chloride 113.5 111.5 109.5 116.3 113.5
Bicarb 35 35 35 30 30
Lactate 0 0 0 0 0
Calcium 3.5 3.5 3.5 2.8 0
Magnesium 1 1 1 1.5 1.5
Gluc (mg/dL) 100 100 0 100 100
Duosol (B.Braun)
• Bicarbonate buffered
• No lactate
• 5 liter bag
• 2 compartments to prevent precipitation
• Three ionic formulations
Chemical Content of DuosolIon (mEq/L) 4450 4451 4452
Sodium 136 140 140
Potassium 2 0 2
Chloride 107 109 111
Bicarb 25 35 35
Lactate 0 0 0
Calcium 0 3 3
Magnesium 1.5 1 1
Gluc (mg/dL) 0 100 100
NxStage PureFlow (NxStage)
• Part of NxStage System One for acute care
• 5 liter bags
• Choice of buffers– Lactate: 3 formulations;
single-chamber bag– Bicarbonate: 5 formulations;
dual-chamber bag
Chemical Content of NxStage PureFlow (1)
Ion (mEq/L)Lactate Buffer
RFP-204 RFP-205 RFP-207
Sodium 140 140 140
Potassium 1 3 1
Chloride 105 112 100
Bicarbonate 0 0 0
Lactate 40 35 45
Calcium 3 3 3
Magnesium 1 1 1
Glucose (mg/dL) 100 100 100
Chemical Content of NxStage PureFlow (2)
Ion (mEq/L)Bicarbonate Buffer
RFP-400 RFP-401 RFP-402 RFP-453 RFP-454
Sodium 140 140 140 130 130
Potassium 2 4 0 2 4
Chloride 111 113 109 108.5 110.5
Bicarbonate 35 35 35 25 25
Lactate 0 0 0 0 0
Calcium 3 3 3 0 0
Magnesium 1 1 1 1.5 1.5
Gluc (mg/dL) 100 100 100 100 100
Choosing a Solution: Issues to Consider
• Cost
• Anticoagulation
• Patient safety
• CRRT modality– Diffusion (CVVHD)– Convection (CVVH)– Both (CVVHDF)
Anticoagulation and Solutions
Solution Calcium?
Normocarb HF No
Accusol 4 Yes; 1 No
PrismaSate 2 Yes; 4 No
PrismaSol 4 Yes; 3 No
Duosol 2 Yes; 1 No
NxStage PureFlow 6 Yes; 2 No
May need to consider Ca++ content if using citrate for anticoagulation
Evaluation of Errors in Preparation of CRRT Solutions
• Survey of 3 Pediatric Listserves:– Pediatric Critical Care, Nephrology, CRRT
• 16/31 programs reported solution compounding errors
• Consequences of improper solutions– 2 deaths– 1 non lethal cardiac arrest– 6 seizures (hypo/hypernatremia)– 7 without complications
Barletta et al, Pediatr Nephrol. 21(6):842-5, 2006 Jun
FDA Approval Status of CRRT Solutions
Solution FDA Label
Normocarb HF Replacement
PrismaSate Dialysate
PrismaSol Replacement
Accusol Dialysate
Duosol Dialysate
NxStage PureFlow Dialysate
• CRRT with citrate regional anticoag
D
R
Putting it All Together: One Approach
• Adjust blend, change saline if indicated
• DIALYSATE: commercial bicarb-based solution
• REPLACEMENT: normal saline
On-Line Dialysate with SLED: An Alternative to Solutions in CRRT
• Extended sessions using standard dialysis equipment
• Dialysate made on-line from concentrates
• Simple, convenient, MUCH cheaper
• Dialysate is not sterile
Citrasate(Advanced Renal Technologies)
• “A” concentrate for dialysis
• Liquid or bulk powder
• Citrate used as acidifying agent
• Local anticoagulation greatly reduces need for heparin
CRRT Solutions: Summary• Solutions needed to maximize clearance
• Bicarbonate has superseded lactate
• Industry-made solutions are available including some approved for replacement
• Pre-mixed, sterile solutions for CRRT are simple, safe, may be costly
• On-line dialysate for SLED is clean (not sterile), simple, cheap
• The best “solution” may still be pending
Thanks!