Anticoagulation Flashcards
What anticoagulant is used for neonatal and pediatric patients?
Heparin (Loading dose for neonatal pt= 100 units/kg
What anticoagulant is a direct thrombin inhibitor?
Bivalridin or Argatroban (not common)
What is the desired range for ACTs? What factors affect how this range is determined?
-Bolus dose of heparin in the NICU> 300s
- Maintenance dose 180-220s
-If the patient is bleeding, ACT 160-180s (for slight bleeding)
- AntiXa for normals is 0.3-0.7 (patient this is bleeding dropped to 0.2-0.25
What elements are required for heparin to work?
ATIII
What test measures the effectiveness of Bivalrudin?
PTT, ACT & TEG
What does PTT measure? What is a normal PTT? What range of PTT values is used for patients on ECMO?
PTT measures how long it takes to form a clot
25-35 is the normal range
ECMO patient range is 60-80 (if stranding/clots seen will increase range)
What are the two pathways in the coagulation cascade? How is each pathway activated?
Extrinsic and Intrinsic
Extrinsic is activated by tissue injury (Factor 3 to Factor 7)
Intrinsic is activated by foreign body and inflammation activation (TF 12)
They both lead to the common pathway at Factor 10
What are the tests used to evaluate anticoagulation in the neonate?
ACT and TEG initially, then AntiXa and PTT
What is the bolus dose of heparin given to a large pediatric or adult patient
10,000 IU
What is the bolus dose of heparin given to an infant or small child?
100 IU/kg
Which drug will CRRT affect? Why?
Heparin
It will pull it across the membrane and clear it out
What is the reversal agent of heparin? Bivalrudin?
Heparin- protamine
Bivalrudin- none
Calculate the bolus dose of heparin for a 4kg patient. (The concentration of heparin is 1000 units/ 1ml)
4kg x 100 IU/kg = 400 IU
1000 IU/ 1ml x 1/400 IU = .4 ml
Calculate the infusion rate of heparin with the following information:
A) concentration of heparin 100 units/ml
B) dose 30 units/kg/hr (infusion)
C) patient weight 4 kg
D) what would you do if the next ACT came back with a level of 240 seconds
Decrease dose per protocol, could do nothing and wean per AntiXa
What is the ACT? What does it measure? What are the units of the ACT?
Activated clotting time
Measures the entire time it takes for a clot to form from whole blood
Seconds
What bedside device(s) are used to run this test?
POC Hemochron Elite
Why is the ACT elevated in the prime?
Only PRBCs are used in the prime then there are no clotting factors
What anticoagulant does the ACT measure best?
Heparin
(A Kaolin activated ACT will give a falsely high measurement for Bivalrudin)
Is the ACT an exact measurement?
No, it has +/- 20% error
What are factors that affect anticoagulation?
Platlet function, temperature, ATIII deficiency, Hypotension, Sepsis, Liver dysfunction, DIC, Body inhabitus
What is the dose of heparin to place in the adult circuit?
No heparin goes into the adult circuit, bolus dose given to patient
What is the dose of heparin for the neonatal circuit?
0.2 mls (20 units)
