CRRT in the ICU : Getting it Right

Annabelle Sy-Lim,MD

May 22, 2012

Learning Objectives

• To discuss the fundamentals of CRRT

• To enumerate the required nursing competencies to perform CRRT

• To present the latest recommendations to improve nursing competencies

Learning Objectives

• To discuss the fundamentals of CRRT

• To enumerate the required nursing competencies to perform CRRT

• To present the latest recommendations to improve nursing competencies

Lecture Outline

• Evolution of CRRT

• Principles involved in CRRT

• Different modalities of CRRT

• Dialysate Fluids

• Principle of Clearance in CRRT

1977 : First CRRT by Kramer

CONVECTION

PRINCIPLE : ULTRAFILTRATION ULTRAFILTRATION

PRINCIPLE OF DIFFUSION DIFFUSION

PRINCIPLE OF ADSORPTION ADSORPTION

Effluent Pump Pre Blood Pump

BLD

Effluent Pressure

Hemofilter

Syringe pump

Filter Pressure

Blood Pump

Return Pressure Air Detector

Return Clamp

Patient

SCUF

Syringe Pump

Return Pressure Air Detector

Hemofilter

Filter Pressure

Effluent Pressure

Access Pressure

Return Clamp

Patient

Post

Post Pre

Replacement Pump Effluent Pump Replacement Pump Pre Blood Pump

CVVH

Dialysate Pump Effluent Pump

Hemofilter

BLD

Effluent Pressure

Filter Pressure

Syringe Pump

Return Pressure Air Detector

Blood Pump Return Clamp

Access Pressure

Patient

Pre Blood Pump

CVVHD

CVVHDF

Hemoperfusion

• Is an extracorporeal treatment that passes the patient’s blood through a filter impregnated with anabsorptive substance, for example, charcoal. This is able to bind to certain toxins in the bloodstream which removes them, returning the cleaned blood to the patient (Kellum, Mehta, Angus,Palevskey, & Ronco, 2002). It has been shown to be effective against drugs like digoxin,glutethimide, phenobarbital theophiline and paraquat among others, and allowed patients tomaintain normal levels of essential molecules (Ponikvar, 2003)

Dialysate Fluids : Differences

• 2 types : lactate based solution and a bicarbonate based fluid.

• Are pre-prepared and packaged ready to use typically in 5 litre bags which are hung below

the machine .

BICARBONATE BASED

• Bicarbonate based solutions are physiologic and replace lost bicarbonate immediately.

• Effective tool to correct acidosis

–Concentration of 30-35mEq/L corrects acidosis in 24 to 48 hours.

BICARBONATE BASED

• Preferred buffer for patients with compromised liver function.

• Mean arterial pressure remains stable

• Superior buffer in normalizing acidosis without the risk of alkalosis

• Improved hemodynamic stability, and fewer cardiovascular events.

Plasma PrismaSate

BK0/3.5

PrismaSate

BGK2/0

Calcium Ca2+ (mEq/L) 4.3 - 5.3 3.5 0

Magnesium Mg2+

(mEq/L) 1.5 - 2.5 1.0 1.0

Sodium Na+ (mEq/L) 135 - 145 140 140

Potassium K+ (mEq/L) 3.5 - 5.0 0 2.0

Chloride Cl- (mEq/L) 95 - 108 109.5 108

Lactate (mEq/L) 0.5 - 2.0 3 3

Bicarbonate HCO3-

(mEq/L) 22 - 26 32 32

Glucose (mg/dL) 65 - 110 0 110

Osmolarity (mOsm/L) 280 - 300 287 292

pH 7.35 - 7.45 ~ 7.40 ~ 7.40

LACTATE-BASED

• Metabolized into bicarbonate providing it’s under normal conditions.

• Lactate is converted in the liver on a 1:1 basis to bicarbonate and can sufficiently correct acidemia.

LACTATE-BASED

• Non physiologic pH value of 5.4

• Is a powerful peripheral vasodilator

• Further acidemia for patients in:

– Hypoxia

– Liver impairment

– Pre-existing lactic acidemia can result in worsening of lactic acidemia

PRINCIPLES OF CRRT CLEARANCE

• CRRT clearance of solute is dependent on the following:

– The molecule size of the solute

– The pore size of the semi-permeable membrane

• The higher the ultrafiltration rate (UFR), the greater the solute clearance.

MOLECULAR SIZES

PRINCIPLE OF CRRT CLEARANCE

• Sieving Coefficient – The ability of a substance to pass through a membrane

from the blood compartment of the hemofilter to the fluid compartment.

– A sieving coefficient of 1 will allow free passage of a substance; but at a coefficient of 0, the substance is unable to pass.

• .94 Na+

• 1.0 K+

• 1.0 Cr

• 0 albumin will not pass

Learning Objectives

• To discuss the fundamentals of CRRT

• To enumerate the required nursing competencies to perform CRRT

• To present the latest recommendations to improve nursing competencies

CRRT Nursing Competency

• What knowledge and skills are essential?

• What resources are needed to support the program? Staff?

– Print, on-line, personnel, 24/7 on-call or on-site

• Collaboration

Nephrology Nurse

• How CRRT works • Reason for treatment • When and how to terminate treatment • Equipment operation • Most common alarms • When and how to reach the nephrology team • Fluid balance calculations • Assessment of clotting • How to adjust AP/VP limits, BFR, or UFR • How to verify dialysis fluid or replacement fluid and/or

rate changes

Bedside Nurse: Competencies

• Verbalize

– How CRRT works (fluid and solute balance, changes in nutrition and medications)

– Reason for treatment

– When and how to terminate treatment

– How to troubleshoot alarms (AP, VP, blood leak, error codes, air detector)

– When and how to recirculate the system

– How to care for catheter and catheter exit site

– When and how to contact nephrologist or nephrology nurse

– How to operate extracorporeal circuit warmer

Bedside Nurse: Competencies

• Demonstrate

– How to calculate fluid balance

– How to assess clotting in the system

– How to adjust AP and VP limits, BFR, UFR

– How to verify dialysis and replacement fluid solution and rates

– Document continuing care in nursing notes and flow sheet

Before Treatment Equipment/Supplies

• Nephrology Nurse – CRRT Equipment/Circuit

• Bedside Nurse – Order dialysis fluid; citrate

and any replacement solutions

– IV tubing for each infusion pump

– 3-way stopcocks

– Extracorporeal circuit warmer

– Extracorporeal circuit prime

– Telephone at bedside

Before Treatment Equipment/Supplies

• Nephrology Nurse – Review and note CRRT orders

– Verify consent

– Notify bedside nurse of treatment orders and initiation time

– Set-up and prime CRRT circuit with heparinized normal saline

– Prime other lines in CRRT circuit

– Verify catheter placement

• Bedside Nurse – Review, clarify, and note CRRT

– Draw baseline labs per CRRT orders

– Explain procedure and answer questions as needed

– Check cannulated limb for circulation

CRRT Treatment Responsibilities: Points to Remember

• Nephrology Nurse

– Initiate treatment based on

individual patient needs as assessed by the nephrologist

• Bedside Nurse

– Do not infuse other medications or blood products directly into the CRRT system

– Cooling effects of CRRT may prevent temperature elevation

– Adjust patient fluid removal rate hourly to maintain net UFR

– Changes in net URF

Treatment Initiation

• Nephrology Nurse – Assess patient’s condition *fluid

and electrolyte – Prep catheter ports – Aspirate appropriate blood

volume from catheter and flush w/saline

– Prime CRRT circuit w/priming solution and attach blood lines of equipment to catheter(s)

– Start citrate drip – After 5’ w/stable VS, start

replacement fluid and ultrafiltration

– Change catheter site dressing if needed

• Bedside Nurse – Assess patient’s condition *fluid

and electrolyte – Baseline VS, Wt, PAWP (if

applicable), CVP, BP, edema, lung/heart sounds, lab values

– VS q 30’ x 2 then q 1 h – Monitor and document starting

AP, VP, DFR, RFR, BFR, URF and infusion pump rates

CRRT Treatment Responsibilities: q 1 hour

• Bedside Nurse

– Monitor system for kinks, loose connections, patient bleeding

– Evaluate changes in pressure reading VP or AP

– Evaluate hemofilter and venous chamber for clotting or fibrin

– Evaluate color of ultrafiltrate (no pink-tinged fluid)

– Document arterial pressure (AP), venous pressure, BFR, and intake/output

CRRT Treatment Responsibilities: q 2 hr into treatment/ q 6 hr thereafter

• Bedside Nurse

– Check circuit ionized Ca++ (sample from venous port) and patient’s ionized Ca++ (sample from site other than CRRT circuit)

– Recheck CRRT circuit/patient ionized Ca++ after any changes in anticoagulation – reference optimal ranges specified

– Notify nephrology nurse if circuit clots

CRRT Treatment Responsibilities: q 24 hr

• Bedside Nurse – Assess patient’s fluid/electrolyte balance and overall condition,

PAWP (if applicable), CVP, edema, lungs, heart

– Evaluate serum chemistry for changes

– Monitor serum calcium and pH for signs of citrate toxicity

– Monitor for s/s of sepsis or local infection

– Monitor for s/s of hypothermia

– Assess and monitor patient’s nutritional status – daily weight, albumin, bowel patterns, skin turgor, muscle wasting

– Monitor the integrity of the access dressing – change per protocol

FLUID MANAGEMENT IN CRRT

• Goal of Fluid Management

– “The patient will achieve and maintain fluid volume balance within planned or anticipated goals”

(ANNA Standards of Clinical Practice for Continuous Renal Replacement Therapy”)

• Considerations

– Intakes and outputs (I&O)

I AND O FORMULA

• Net fluid removal hourly (physician order)

• +

• Nonprisma intake (IV, TPN, etc.)

• - • Nonprisma output (urine, etc.)

• =

• Patient Fluid Removal Rate (set in prisma)

Typical Calculation of Fluid Balance

Learning Objectives

• To discuss the fundamentals of CRRT

• To enumerate the required nursing competencies to perform CRRT

• To present the latest recommendations to improve nursing competencies

CRRT Competency Management

1. Organize your CRRT competency assessment – Determine critical competencies to evaluate annually – Tie critical competencies to annual performance reviews

2. Understand JCAHO expectations – National Patient Safety Goals

3. Develop your CRRT competency assessment program – Design a compliant, consistent, and effective competency assessment

program

4. Validate CRRT competency – Validate clinical proficiency

5. Maintain a consistent CRRT validation system – Ensure that clinical proficiency is assessed and validated in a consistent

manner with our easy to implement skill sheets

6. Keep up with new CRRT competencies – Verify and document new—and existing—competencies, including those for

new equipment

Staffing Nurses for CRRT

• Variations – Skill mix – Opened vs. Closed – Responsibilities

• Dialysis • Critical Care

• Predictions – FTEs by shift – Budgeting FTEs

• Shortages • Effects

– Clinical Outcomes – Therapy Choice

Safety/Quality

• Protocols

• Order sets

• Solutions

– Stability, expirations, FRF/dialysate, medication management, compounding

• Managing complications

• Anticoagulation

• Access (where, size)

• Time out?