Terminology and Common Issues in Pediatric CRRT John Gardner RN, BSN Nurse Manager Pediatric Nephrology & Transplant DeVos Children’s Hospital Grand Rapids Michigan

Over View Terminology Common issues Access Anticoagulation Extracorporeal circuit size Blood priming Hypothermia Staffing

Terminology SCUF slow continuous ultrafiltration CAVH continuous arteriovenous hemofiltration CAVHD continuous arteriovenous hemodialysis

Terminology CVVH continuous venovenous hemofiltration CVVHD continuous venovenous hemodialysis CVVHDF continuous venovenous hemodiafiltration

CVVH/CAVH Convective clearance Replacement solutions Physiologic sterile solution that is either infused pre filter (NA) or post filter (outside of NA) that infused at a set rate (Qr) CAVH/CVVH: Convective Clearance

CAVHD/CVVHD Diffusive Clearance CVVHD/CAVHD Diffusive clearance Dialysate Physiologic sterile solution that is infused countercurrent to the blood flow rate (Qd)

CVVHDF/CAVHDF Convective clearance Replacement solutions Diffusive clearance Dialysis solution CAVHDF/CVVHDF Convective and Diffusive Clearance

Urea Clearance CVVH Vs CVVHD (Maxvold Et Al, Crit Care Med, April 2000) Study design Fixed blood flow rate-4 mls/kg/min HF-400 (0.3 m2 polysulfone) Cross over for 24 hrs each to FRF or Dx flow at 2000 mls/hr/1.73 m2 TPN protein delivery at 1.5 gms/kg/day

Comparison of Urea Clearance: CVVH Vs CVVHD (Maxvold Et Al, Crit Care Med April 2000) Urea Clearance (mls/min/1.73 m2) BFR = 4 mls/kg/min FRF/Dx FR = 2 l/1.73 m2/hr SAM = 0.3 m2 p = NS

Vascular Access Properly functioning access is key to successful CRRT therapy Adequacy Filter life Decreased blood loss Staff satisfaction

Ideal Catheter Characteristics Easy insertion Permits adequate blood flow without vessel damage, large diameter with shortest length Low resistance, decreased arterial and venous pressures Minimal technical flaws High recirculation rate Kinking

Vascular Access Placement Femoral Internal jugular Sub-clavian (avoid if possible) Match catheter size to pt. Size and anotomical site One dual- or triple-lumen or two single lumen uncuffed catheters

Common Causes of Poor Catheter Flow Rates Catheter tip position – is the tip in proper placement? Kink Tight suture Clamp Decreased intrvascular volume Increased intrathoracic pressure Thrombosis or fibrin sheath formation

Comparison of Upper Vs. Lower Body Location Line Placement (Kendall 8 Fr 9 and 12 Cm N = 20; 120 Treatments) P value NS NS NS NS Gardner et al, CRRT San Diego 1998

Why Do We Need Triple Lumen Access?

(Citrate = 1.5 x BFR 150 mls/hr) (Ca = 0.4 x citrate rate 60 mls/hr) Normocarb Dialysate Normal Saline Replaceme nt Fluid Calcium can be infused in 3 rd lumen of triple lumen access if available. (BFR = 100 mls/min) ACD-A/Normocarb Wt range 2.8 kg – 115 kg Average life of circuit on citrate 72 hrs (range hrs) Pediatr Neph 2002, 17:

Citrate ~ running it Arterial access Venous access Citrate infusion via “y” adaptor

“arterial” line Venous line CaCl infusion line/or TPN/or Med line

Anticoagulation Heparin Initial bolus 10 to 30 mg./ Kg Continuous infusion of 10 to 30 mg./Kg Maintain an activated clotting time (ACT) of Risks of heparin anticoagulation: Bleeding Thrombocytopenia

Anticoagulation Citrate Citrate infusion to CRRT circuit Calcium infusion to to patient via separate central line Monitor post filter ionized calcium, adjust citrate infusion per protocol Monitor systemic ionized calcium, adjust calcium infusion per protocol Monitor for metabolic alkalosis and citrate loc

Extracorporeal Circuit Volume Circuit volumes should be < 10% of the patients intravascular blood volume Human blood volume formula < 10kg 80ml/kg >10kg 70ml/kg Removal of > 10% blood volume extracorporeal can result in hemodynamic instability (shock)

Blood Priming Indications Circuit volume >10% of the patients blood volume Hemodynamic instability

Complications of Blood Priming PRBC from the blood bank tend to have an increased potassium The HCT of PRBC is around 80% A 50% dilution with normal saline or 5% albumin should be performed prior to circuit prime Bradykinin release syndrome may be seen with AN- 69 membranes (brophy,et al 2001ajkd) System clotting

Blood Priming Methods More concerning with AN-69 or membranes, less concerns with polysulphone membranes Zero balance ultrafiltration (Z-BUF) Normalizes electrolytes and improves acid-base status of the prime prior to pt connection by performing CVVH, CVVHD or CVVHDF for 30 minutes  Hackbarth et al, Peds Neph, : Bypass maneuver The patient is transfused with the PRBC at the same time and rate as the circuit is primed with the patients blood. The NS prime is wasted  Brophy et al, am J kid Dis, 2001 Jul;38(1):173-8

Hypothermia Significant in pediatrics The smaller the more difficult Heat loss related to rate of blood flow and volume of blood in circuit Blood flow rate Higher blood flow rate decrease heat loss due to less time outside of the body

Hypothermia Nursing Intervention External warming devices Radiant warmers Baer hugger Heating mattress Blood warmers Solutions heaters Monitoring Skin breakdown and patient temperature

Staffing Staffing ratios Education System setup Pump management Program management

A National Survey (April Tanner RN, Atlanta Ga, PCRRT 3, Orlando 2004) An national review of current trends in CRRT An 18 question survey sent to pediatric centers that offer CRRT Free-standing or based in adult facility 42 centers responded

Staffing Ratios

Education Wide variety of teaching methods Didactic/hands on skills lab training occurs in 69% of initial training sessions 12% require mentoring shifts 17% offer informal training 7% utilize bedside training methods

Education Annual recertification - 43% More frequent recertification occurs 26% Smaller volume programs 19% of programs have no formal annual competency or recertification programs Many centers education programs are under review

System Set-up

Logistics and Coordination of System Set-up 11 of 42 centers have no formal 24/7 coverage In 93% of center’s RNs manage the pump Dialysis, ECMO, and physicians make up the other % Charge structure The dept.That sets up equipment receives revenue in majority of centers 21 of 42 centers also have daily charges  Varied response as to where revenue goes

Conclusion The education and competency of the bedside staff is essential for successful care of a child on CRRT No better teacher than the child Communication to colleagues throughout your program and throughout the world are critical in improvement in over all care

Thank You