What form of anticoagulation is the “best” Or why is Citrate better then Heparin or Prostacyclin

What form of anticoagulation is the “best”

Or why is Citrate better then Heparin or Prostacyclin

Anticoagulation and clotting

• Any blood surface interface– Hemofilter– Bubble trap– Catheter– Areas of turbulence resistance

• Luer lock connections / 3 way stopcocks

Sites of Action of CitrateContact Phase (intrinsic)

XII activationXI IX Ca++

Tissue Factor (extrinsic)TF:VIIa

THROMBIN Ca++

fibrinogen

prothrombin

X Xa Va VIIIa Ca++ platelets

CLOT

platelets / monocytes / macrophages

CITRATECitrate

• ACD-A (Baxter, Deerfield, IL)– 1000 cc bag, industry standard

• CaCl 8 gms/1 liter of NS– pharmacy made

• Normocarb Dialysis/Replacement Soln (Dialysis Soln Inc)– Can be prepared at bedside or pharmacy

• Normal Saline

Solutions needed for Citrate Protocol

(Pediatric Nephrology 2002 17:150-154 )

(Citrate = 1.5 x BFR150 mls/hr)

(Ca = 0.4 x citrate rate60 mls/hr)

Normocarb Dialysate

Normal Saline Replacement Fluid

Calcium can be infused in 3rd lumen of triple lumen access if available.

(BFR = 100 mls/min)

ACD-A/Normocarb Wt range 2.8 kg – 115 kgAverage life of circuit on citrate 72 hrs (range 24-143 hrs)

Pediatr Neph 2002, 17:150-154

Citrate: Technical Considerations• Measure patient and system iCa in 2 hours then at 6

hr increments• Standing protocol on nursing flow sheet adjusted by

bedside ICU nurse• Pre-filter infusion of Citrate

– Aim for system iCa of 0.25-0.4 mmol/l• Adjust for levels

• Systemic calcium infusion– Aim for patient iCa of 1.1-1.3 mmol/l

• Adjust for levels

Orders for citrate and Ca rates(adapted for N Gibney)

CITRATE INFUSION SLIDING SCALE CALCIUM INFUSION SLIDING SCALE

PRISMA iCa++ INFUSION ADJUSTMENT PATIENT iCa++ INFUSION ADJUSTMENT

>20 kg < 20 kg > 20 kg < 20 kg

< 0.25 by 10 ml/hr by 5 ml/hr > 1.3 by 10 ml/hr by 5 ml/hr

0.25 – 0.4(Optimum range)

Noadjustment

Noadjustment

1.1 – 1.3(Optimum range)

Noadjustment

Noadjustment

0.4– 0.5 by 10 ml/hr by 5 ml/hr 0.9 – 1.1 by 10 ml/hr by 5 ml/hr

> 0.5 by 20 ml/hr by 10 ml/hr < 0.9 by 20 ml/hr by 10 ml/hr

NOTIFY MD IF CITRATE INF. RATE > 200 ML/HR NOTIFY MD IF CALCIUM INF. RATE > 200 ML/HR

• Seven ppCRRT centers– 138 patients/442 circuits– 3 centers: hepACG only– 2 centers: citACG only– 2 centers: switched from hepACG to citACG

• HepACG = 230 circuits• CitACG= 158 circuits• NoACG = 54 circuits• Circuit survival censored for

– Scheduled change– Unrelated patient issue– Death/witdrawal of support– Regain renal function/switch to intermittent HD

ppCRRT ACG Side Effects

• Heparin– 11 cases of systemic bleeding on heparin– 5 cases no ACG used secondary to bleeding– 1 case of HIT

• Citrate– 19 cases of metabolic alkalosis

• 1 change to heparin for hyperglycemia• 1 change to heparin for alkalosis

– 3 cases of citrate lock

Complications of Citrate:

• Citrate Lock– Seen with rising total Ca with dropping patient

ionized Ca due to citrate delivery exceeds citrate clearance

– Rx of “citrate lock”• Increase clearance and decrease citrate rate

• Metabolic Alkalosis – Resolved with NaHCO3 bath of 25 meq/l

Incidence

• In a recent survey of PICU and CRRT databases in NA 70% of all programs use citrate as a primary mode of anticoagulation to avoid bleeding risks