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 Citrate
Contact Phase (intrinsic)Contact Phase (intrinsic)
XII activationXII activation
XI IX Ca++XI IX Ca++
Tissue Factor (extrinsic)Tissue Factor (extrinsic)
TF:VIIaTF:VIIa
THROMBIN Ca++THROMBIN Ca++
fibrinogenfibrinogen
prothrombinprothrombin
XX
XaXa
VaVa
VIIIaVIIIa
Ca++Ca++
plateletsplatelets
CLOTCLOT
platelets / monocytes / macrophagesplatelets / monocytes / macrophages
CITRATECITRATE
Citrate
•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 forCitrate Protocol(Pediatric Nephrology 2002 17:150-154 )
(Citrate = 1.5 x BFR
150 mls/hr)
(Ca = 0.4 x citrate rate
60 mls/hr)
NormocarbDialysate
NormalSalineReplacement Fluid
Calcium can be infused in 3rdlumen of triple lumen access ifavailable.
(BFR = 100 mls/min)
ACD-A/Normocarb Wt range 2.8 kg – 115 kg
Average 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 6hr increments
•Standing protocol on nursing flow sheet adjusted bybedside 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)
No
adjustment
No
adjustment
1.1 – 1.3
(Optimum range)
No
adjustment
No
adjustment
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 patientionized Ca due to citrate delivery exceeds citrateclearance
–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 databasesin NA 70% of all programs use citrate as aprimary mode of anticoagulation to avoidbleeding risks