title: Table 2. Heparin dosing based on APTT levels (therapeutic range 60-85 seconds)
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  Table 2. Heparin dosing based on APTT levels (therapeutic range 60-85 seconds)
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  bet | 260/654 | Sana | 03.01.2022 | Hajmi | 1,5 Mb. | | #14803 |
  Table 2. Heparin dosing based on APTT levels (therapeutic range 60-85 seconds).1,4
  APTT (seconds)
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  Bolus (units/kg)
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  Hold (min)
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  Rate change (%)
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  Time until repeat APTT
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  <50
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  50
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  0
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  +10
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  6 h
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  50-59
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  0
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  0
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  +10
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  6 h
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  60-85
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  0
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  0
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  No change
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  Next day or as per haematologist advice
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  86-95
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  0
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  0
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  -10
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  6 h
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  96-120
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  0
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  30
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  -10
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  6 h
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  >120
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  0
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  60
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  -10
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  6 h
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  Obtain blood for APTT 6 hours after administration of loading dose and 6 hours after every change.
  When APTT values are therapeutic, blood count and APTT daily or as per the advice of haematologist.
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  APTT: Activated partial thromboplastin time
  Vascular catheter patency.1,2,5-7,18-21
  Maintenance of patency of peripheral arterial catheters: 0.5 units/mL of IV fluid.
  Maintenance of patency of central vascular catheters: 0.5 units/kg/hour
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  Dose adjustment
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  Therapeutic hypothermia – No information.
  ECMO – Refer to local ECMO protocols for anticoagulation.
  Renal impairment – Dose adjustment may be required in severe renal impairment. Discuss with haematologist.
  Hepatic impairment – No dose adjustment is required.8
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  Maximum dose
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  Total cumulative dose
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  Route
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  IV
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  Preparation
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  Antithrombotic prophylaxis
  The concentrations varying from 100 to 500 units/mL can be used for loading doses and concentrations of 10 to 500 units/mL can be used for continuous IV infusion.
  Vascular catheter patency
  To prepare 0.5 unit/mL solution, withdraw 5 mL 0.9% sodium chloride from a 100 mL bag, then add 5 mL of 50 units/5 mL (50 units) to make 50 units in 100 mL bag.
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  Administration
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  Systemic antithrombotic therapy
  Administer IV loading dose over 30 minutes.
  Administer maintenance dose as a continuous IV infusion and titrate dose by anti-Xa (or APTT if anti-Xa is not available).
  Vascular catheter patency
  Arterial lines: Continuous IV infusion of 0.5 units/mL at 0.5-1 mL/hour.
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  Monitoring
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  Antithrombotic prophylaxis
  Six hours after initiating therapy, measure anti-Xa (or APTT if anti-Xa is not available), then adjust dose to achieve anti-Xa level of 0.3 to 0.7 unit/mL (equivalent to APTT of 60 to 85 seconds) – Refer to tables 1 and 2 in the dosing section.
  Platelet count before the commencement and then weekly.
  Assess for signs of bleeding and thrombosis.
  Vascular catheter patency
  Standard observations for intravascular catheters.
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  Contraindications
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  Known hypersensitivity to heparin, uncontrolled bleeding.
  Intraventricular haemorrhage, gastrointestinal haemorrhage, thrombocytopenia < 50 x 109/L, severe hypertension,
  Eye, brain or spinal cord surgery- Surgeons to give clearance regarding when to start heparin.7
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  Precautions
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  Bleeding disorders – Discuss with haematologist.
  Store heparinised saline ampoules separately from other heparin products and sodium chloride 0.9% ampoules to reduce the risk of selection errors
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  50>
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