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CRRT Machines

Akash DeepDirector - PICU

King’s College Hospital London

ChairRenal/CRRT Section

European Society of Paediatric and Neonatal Intensive Care (ESPNIC)

CRRT Machines• Evolution of CRRT and machines• Ideal CRRT machine• Outline of few available CRRT machines

internationally

CRRT Historical Perspective Continuous Arterio-Venous

Hemofiltration(CAVH): first CRRT modality described in 1977 for hemodyanamically unstable AKI patients

• Considered a ‘derivative’ therapy to chronic hemofiltration

• Continuous arterio-venous hemodialysis(CAVHD) developed in mid-1980’s to improve small solute clearance

Problems with continuous AV therapies

• Circuit blood flow dependent on patient’s blood pressure

• Need for large bore arterial catheter( bleeding, thrombosis)

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Historical Perspective• Development of early veno-venous CRRT systems:

“adaptive technologies” (late-1980’s to mid-1990’s)Double lumen venous catheters revolutionary Roller Blood pump – blood flow could be

programmed Ancillary pumps to control rates of dialysate

(CVVHD) or replacement fluid (CVVH) – accurate delivery

Semi-integrated systems: blood pump, ultrafiltration controller, and fluid pump all in same module (“open loop”)

CRRT Technology evolution

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My CRRT Machine• Safety

• Performance

• User friendly

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Ideal CRRT machine• Inexpensive• User Friendly • Adequate technical devices and supplies• Specific extracorporeal circuits• Precise UF control systems• Compatible fluids for replacement• Adequate anticoagulation regimens• Thermoregulation• Accurate monitoring systems to improve quality of

management, safety, and performance

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SafetyIdeal extracorporeal circuit must incorporate continuous pressure measurements and continuous displays of pressures from:Inlet and outlet lumens of the catheterInlet and outlet of the filterUltrafiltrate and dialysate ports.

This information integrated with adequate alarms is of crucial importance in allowing ICU staff to maintain filter efficiency and circuit patency and to detect potential sources of clotting and ensuring patient safety.

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Newer CRRT Machines• Integrated blood modules• Pressure sensors as safety checks – check

on access issues and circuit clotting/clogging• Fluid balancing controls• Blood flow rates up to 500 ml/min• Increased dialysate and replacement fluid

flow rates• Highly permeable membranes

Newer CRRT Machines• Higher surface area dialyzers• Simplified priming procedures• User friendly operator interface -wide color

screen allows easy access to the required information and on-line help for most of the functions

• Data extraction capabilities• Automatic data printing• Transportability of machine – treatment

provided at different parts of hospital

Summary- New machines• Machines of today have to have safety

features in place

• In addition capable of performing high tech modalities with extreme precision and accuracy.

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Descriptors • Dialyzer

- Any dialyzer

-Cartridge• Pumps

-Number

-Purpose• Modes• Min/Max Ultrafiltration rate• Min/Max effluent flow• Volume Control

- Volumetric

- Gravimetric• Alarms• Safety features• Blood warmer

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CRRT Machines• Prisma• Prismaflex• Diapact• Aquarius• NxStage• Fresenius 2008 K• Carpidiem - Neonatal

Prisma(Gambro) • Preassembled cartridge with lines and dialyser

• Compact large monitor with touch screen features

• 4 pumps and 3 scales -SCUF

-CVVH

-CVVHD

-CVVHDF

- PLASM EXCHANGE

• Flow rates - QB 0-180 ml/min

- QD 0- 2500 ml/hr

- QRF 0-2000 ml/hr

- Total Effluent 5000ml/hr• Replacement Fluid - Pre

- Post

- Simultaneous pre- and post-

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Problems with PRISMA• Rigidity of prescription and performance - pre-

fixed filter and circuit set with only 2 surface areas available

• Pre-designed circuit with either pre or post dilution – NO interchange of therapy possible

• Blood flow limited to 180 mls/min• Heater for dialysate/replacement fluid not an

option

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Prismaflex ( Baxter-Gambro)• New features to perform therapies with high fluid volume

exchange• 5 pumps, 4 scales• Disposable set with pre-connected high flow dialyzer and

circuit

-SCUF

-CVVH

-CVVHD

-CVVHDF

• TPE/MARS ( future use)

• Fifth pump- Pre- Blood-Pump : Allows for citrate infusion just after connection between arterial access and blood line

Blood Inlet at the bottom of dialyser• Flow rates

- Blood pump bigger than Prisma QB 10-450ml/min

- Total effluent 10,000ml/ hr

- Maximum UF of 2000ml/ hr• Replacement Fluid – Pre and /or post• In-line blood heater

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Blood pump

Pre-blood pump

Blood heaterEffluent

pump

Prismaflex• Gravimetric fluid balance system

provide check & balance for precise fluid exchange & accurate patient fluid removal

• Real-time dose indicator assesses prescription delivery

• Deaeration chamber collects & removes air while minimizing clotting

• Can change pre- and post- infusion mixing points during a treatment using the same set by pinch valves without interrupting therapy

• Membranes: M and HF series (ST)

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Aquarius ( Nikkiso )• Automatic priming• 4 pumps and 6 pump models (newer

version) AND 2 scales

- Citrate & Calcium pumps for RCA• Therapies

-SCUF

- CVVH, CVVHD, CVVHDF

- TPE

- Hemoperfusion• Flow rates

- QB: 30-450 ml/min ( adult)

- Dialysate/Replacement- up to 10L/hr

- Filtrate- up to 12L/hr

- Up to 20L can be hung on scales• Replacement Fluid

- Pre- and/ or post-dilution22

Heparin syringe

Colour Coding

NxStage System One• Bag Changes

- Free from waste bag changes

- Eliminates blood pump stopping for bag changes

• Portable with no plumbing/electrical needs

• Cartridge

- Drop- in loading and engagement of all pumps and safety systems

- One set delivers all therapies

- No prime intervention

- No blood/air interface in cartridge

Optimizes BF and reduces clotting

• Volumetric balancing chambers incorporated into the cartridge

- Will not allow fluid imbalance to overridden alarms

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A Dedicated Neonatal CRRT Machine?• CA.R.PE.DI.E.M. (Cardio–

Renal Pediatric Dialysis Emergency Machine)

• Miniaturized, transportable• Weight range- 2- 9.9 kg(BSA

0.15-0.5M2)• Lines and filters to limit

extracorporeal blood volume• Hardware and software

accurate for low flows and low UF volumes

• Dedicated rather than adapted

Characteristics• 6 inches of user interface• 3 40-mm-diameter roller pumps• 2 scales• 3 pressure transducers. • 3 pre-assembled circuits• Polysulphone membranes - surface area of 0.075, 0.147, and

0.245 m2 • priming volumes - 27.2, 33.5, and 41.5 ml, with the circuit

included (extracorporeal blood volume)• Blood pump flow rate – 5-50 mls/min• Max total UF/dialysis/ HF - 5mls/ min • Treatment set up – Blood flow, dialysate/HF, net UF regulation

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CARPIDIEM By Ronco

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My machineNo suggestion to choose a model or prefer one over the other •MAKE SURE IT DOES WHAT YOU INTEND TO ACHIEVE•LOCAL USAGE, STAFF FAMILIARITY,PATIENT POPULATION•FINANCIAL IMPLICATIONS •SUPPORT SYSTEM IMMENSELY IMPORTANT•ONGOING TRAINING OF STAFF - SIMULATION

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Acknowledgement• Tim Bunchman and pCRRT Foundation

• CRRT online

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