A 44 year old male presents with dyspnoea and is diagnosed as having multiple pulmonary emboli on Computerised tomography pulmonary angiogram (CTPA). He is commenced on 1000 units of heparin per hour after a 5000 unit bolus. During the night his heparin has steadily increased to 1500 units per hour.
These blood results are from the next morning.
Test |
Value |
Normal range |
PT |
12 sec |
12-16 |
APTT |
*38.3sec |
25.0-37.0 |
Fibrinogen |
3.8 g/ L |
2.20-4.30 |
D-DIM LIA |
*>20.0 mcg/ml |
<0.5 |
a) Give 2 reasons for the relatively low APTT despite heparin therapy
b) List 4 causes for an increased predisposition to venous thromboembolic disease
a) Give 2 reasons for the relatively low APTT despite heparin therapy
1 – Inadequate heparinisation
2. ATIII deficiency
3. Increased heparin clearance
4. Increased heparin binding proteins
(1.5 marks)
b) List 4 causes for an increased predisposition to venous thromboembolic disease
Protein C def Protein S def AT III def Malignancy
Factor V Leiden
Lupus anticoagulant
This question is identical to Question 13.2 from the second paper of 2013.