Troubleshooting Issues in CVVH

Timothy L. Kudelka RN, BSN

Pediatric Dialysis Program

C.S. Mott Children’s Hospital

University of Michigan

Where to Begin?

• As Nephrologist, Intensivist and Nurses we all need to address the issues of troubleshooting CRRT.

• Many systems are still adapted (pieced) and others now self-contained with simplified operating interface and build-in software.

• Troubleshooting issues still remain.

Access

• If you don’t have it you might as well go home.

• This is the most important aspect of CVVH therapy.

• Adequacy.• Filter life.• Increased blood loss.• Staff satisfaction.

Troubleshooting Access

• How can you tell if you have a problem before starting?

• Check placement first, then use syringe to test resistance and blood return.

• What if you have problems during treatment?

• Check line for kink, then assess patients position or need for sedation.

Access• Clotting or sluggish catheter.

• tPA (tissue plasminogen activator). (Spry et al., Dialysis&Transplantation. Jan. 2001).

• Normal saline flush.

• Reason to replace catheter.• Clotted catheter with no response to tPA.• Exit site blood leakage with no response to pressure

dressing.• Severe kinked catheter.• Bad re-circulation issues.

Pressures• Arterial or outflow pressures

• High negative pressure = access problem.• High positive pressure = filter problem.• Moderate to high positive pressure + high return (venous)

pressure = access problem.

• Venous or return pressures• Moderate to high positive pressure + high arterial pressure =

filter problem.• High return pressure + moderate arterial pressure = access

Anticoagulation

• None.

• Heparin.• Bolus 10-20 units/kg then infuse at 10-20 units/kg/hr

adjust per ACT.(Heparin induced thrombocytopenia).

• Citrate.• Initiate infusion rate at 1.5x the BFR(in mls/hr).• Calcium chloride infusion at 0.16x the citrate rate. (Hypocalcemia,metabolic alkalosis.

Suggestion

• Normal saline flush.

• Flashlight lines and filter.

• Correct priming technique.

• Maintain good BFR.

• Monitor ACT levels (200-250).

• Quick response to troubleshooting issues.

Ultrafiltration

• How much to ultrafiltrate?

• Net ultrafiltration should be in the range of 1-2 mls/kg/hr.

• Neonates u/f rate 0.5-1ml/kg/hr.

U/F Issues• Attention to intravascular volume.

• Oncotic pressures.

• U/F controllers.– Infusion pumps up to 30% inaccurate. (Smoyer et al, CRRT1998)

• Filter size and life.

U/F Issues

• Accurate assessment is difficult with less room for error in smaller children.– Bed scales.– Frequent weights or weights of U/F in IV

controller U/F method.– Measured volume status.– Monitor sHct.– Vasopressor clearance.

Membrane Reactions

• Bradykinin release syndrome

• Causes of syndrome• ACE inhibitors • Low blood ph

• AN-69 membranes have been associated with “Bradykinin release syndrome” (Brophy et al. AJKD 2001)

Membrane Reactions

• What is the common link?– AN-69 membrane.– Blood prime.– Low ph. (Blood bank blood ph).

• Technique to reduce membrane reaction.

Membrane Reactions

• Correct blood from the blood bank.

• Bypassing the membrane.

• Bypass maneuver.

Bypass Maneuver

To view this dialysis clip, go to the Resources References and Procedures folder, then the UNHS Procedures folder on the CD-Rom.

Thermal Issues

• Patient.– Radiant heat methods.

• Warming blankets.• Overhead warmer.• Warm water bottles.

– Prevention of heat loss.• Environmental conditions.• Exposure. (Hats on infants, plastic wrap).

Thermal Issues

• Circuit– Blood

• Blood warmers Extracorporeal volume Risk of clotting

– Dialysate or replacement fluid• Prismatherm®

• High volume fluid warmer.

Transport Issues

• Patient that require transport while on CVVH.– Battery pack.– Re-circulation.

• Blood prime/blood loss.• Machine issues.• Length of re-circulation. (1-2 hrs).

Prescription

• Need for daily orders.

• Recommendations on order sheet.

• Types of solutions.– PD are problematic r/t lactate and high glucose.– Pharmacy made solutions risk of error and expensive.

– Bicarbonate based solution-less risk, expense.

• Nursing orders/labs.

Nursing Report

• Standard forms for documentation.

• Review of orders.

• The key to good team work is accurate nursing reporting of problems and troubleshooting techniques.

Nursing Training

• Basic concepts of CRRT.• Knowledge of circuit function.• Documentation and review of protocols.• Troubleshooting issues and techniques.• Simulator – for non-stressful practice.• One-on-one hands on with experienced staff.• Continuous education.• Development and implementation of QA tool.

Forms

• Forms available on your CD-ROM

Thanks To:

Dr. Timothy E. Bunchman MD

Dr. Patrick D. Brophy MD

University of Michigan Pediatric Dialysis Team.

Pediatric Critical Care Nursing.

My Wife.