Post on 30-Dec-2015
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