Practical Considerations for CRRT

Helen Currier RN, BSN, CNNNancy McAfee RN, BSN, CNN

Advantages of CRRT

• SLOW: Hemodynamically unstable patients may not tolerate the rapid ultrafiltration of intermittent hemodialysis

• CONTINUOUS: Can help preserve metabolic stability in critically ill patients; can maintain fluid balance for oliguric patients who require high daily input (IV medications, parenteral nutrition)

CVVH SYSTEM

Venous chamber

Replacement fluid

Heparin Drainage bag/UF

From the patient

To the patient

Roller pump

Hemofilter

IV pump

Air detector

bm14 roller pump

Roller pump

Venous chamber

Replacement fluid

Heparin

Drainage bag/UF

From the patient

To the patient

Roller Pump

Hemofilter

IV pump

Dialysate

IV pump

Air detector

bm14 roller pump

Roller Pump

CVVHD SYSTEM

Success with CRRT

• Access• Equipment• Tubing/filter• Prime• Anticoagulation• Staffing

Access-What Works?

• Hemodialysis /Pheresis Line• Shortest, fattest catheter possible

(highest flows with least resistance)

• May need two single lumen lines

• Leg position-be creative

• Tape on the skin-may need to get creative

Blood Pump Systems for

CRRT

CRRT Machines: Current Generation

Tubing and Equipment

• Tubing volume ranges from 44-110 ml

• Filter volume ranges from 28 – 83 ml

• Hotline volume 18.5 ml

• Blood volume of patient (~70 ml/kg)

• PRISMA – 108 ml

• BM-25 -Smallest filter + tubing + hotline = 90.5 ml

Extracorporeal Volume

• Blood volume in extracorporeal circuit is very large compared to a small infant or child

• Patients require a blood prime if the circuit >10% of their blood volume

Blood Prime

• Whole blood• PRBC + Albumin 5%• PRBC + NS• PRBC + FFP• Larger patients Albumin 5%• AN-69 filter requires special

considerations

• What is the link– Blood bank blood has

• ICa of 0.04 mmol/l• K+ of 40-60 mEq/l• pH of 6.4

• Reaction can be mitigated by buffering the blood and giving IV calcium at initiation

Bradykinin Release Syndrome

(Brophy et al Am J Kidney Dis. 2001 Jul;38(1):173-8 )

Buffered System

• ECMO circuits are commonly primed with a cocktail to correct the pH, Hct, and K of banked blood – Addition of THAM

– calcium chloride – Heparin– Sterile Water– Sodium bicarb

Bypass System

• Transfuse the PRBC post-filter directly into the patient

• The patient is then connected to the circuit

• Using the same rate for priming on and infusing the PRBC (mixed with NS or Alb)

• Thus the patient’s blood can be used as a “bradykinin filter” (Brophy,et al 2001AJKD)

Thermal Regulation

• Hotline® Blood warming tubing• Place at venous return to patient• Leave on at constant

temperature of 39o C• Treat temp elevations if they

occur

Anticoagulation

Heparin• Heparin bolus then

continuous infusion• Maintain activated

clotting time (ACT) ~200

• Risk of bleeding, thrombocytopenia

Citrate

• Citrate infusion to CRRT circuit

• Calcium infusion to patient at separate site

• Monitor for metabolic alkalosis

CRRT Staffing in PICU/IICU

• Nephrology/Dialysis RN sets-up & initiates therapy

• PICU/IICU RN manages patient• Nephrology/Dialysis RN on call 24/7• Acuity assigned to pump as if a

separate patient• Staffing determined by acuity

3rd International Conference on Pediatric Continuous Renal

Replacement Therapy (PCRRT)

June, 2004Coronado Springs Disney Orlando,

Flwww.pcrrt.com

CRRT Modalities

• CAVH: Continuous Arteriovenous Hemofiltration

• SCUF: Slow Continuous Ultrafiltration

• CVVH: Continuous Venovenous Hemofiltration

• CVVHD: Continuous Venovenous Hemodialysis

bm25™: Blood Pump Module

• Blood monitor– Blood flow rate:

30-350 mL / min

-- Safety features: pressure monitors

air detector

clot trap

venous clamp

blood leak detector

bm25™: Fluid Control Module

• Balancing monitor– Substitution pump / filtrate

pump– Integrated scales– Fluid heater– TMP monitor

– Operational ranges• Replacement fluid 300-

9000 mL/hr • Filtrate pump 100 - 11,000

mL/hr• Net UFR 0.1 – 2000 mL/hr

• 2 integrated modules

– Blood module (bm 11a™)

– Balancing module / scales (bm14™)

Baxter bm25™

CRRT Modalities

• CAVH: Continuous Arteriovenous Hemofiltration

• SCUF: Slow Continuous Ultrafiltration

• CVVH: Continuous Venovenous Hemofiltration

• CVVHD: Continuous Venovenous Hemodialysis

bm25™: Blood Pump Module

• Blood monitor– Blood flow rate:

30-350 mL / min

-- Safety features: pressure monitors

air detector

clot trap

venous clamp

blood leak detector

bm25™: Fluid Control Module

• Balancing monitor– Substitution pump / filtrate

pump– Integrated scales– Fluid heater– TMP monitor

– Operational ranges• Replacement fluid 300-

9000 mL/hr • Filtrate pump 100 - 11,000

mL/hr• Net UFR 0.1 – 2000 mL/hr

• 2 integrated modules

– Blood module (bm 11a™)

– Balancing module / scales (bm14™)

Baxter bm25™

CVVH SYSTEM

Venous chamber

Replacement fluid

Heparin Drainage bag/UF

From the patient

To the patient

Roller pump

Hemofilter

IV pump

Air detector

bm14 roller pump

Roller pump

Venous chamber

Replacement fluid

Heparin

Drainage bag/UF

From the patient

To the patient

Roller Pump

Hemofilter

IV pump

Dialysate

IV pump

Air detector

bm14 roller pump

Roller Pump

CVVHD SYSTEM