What conditions will prolong both PT and aPTT?

Question

What is the importance or significance of performing a mixing study in patients who presents with isolated prolongation of aPTT?

Answer 1

too much heparin will cause a prolonged PT and PTT. also an excess of Coumadin will cause both to be elevated.

mixing studies aren't done very often. it is used to determine if the elevation is due to a factor deficiency the anticoagulant.

in most instances the dr is aware of the patient's condition, meds being used and at what dosage... mixing studies aren't needed.

Answer 2

Uncontrolled heparin use will affect the aPTT (activated partial thromboplastin time). PT (prothrombin time) will be affected by coumarin derived drugs such as warfarin.
Coagulation disorders such as Hemophilia A and B can greatky affect both. Dengue hemmorhagic feve which is usually foud here in the tropics also affects PT. It causes internal hemmorhage as the infection spreads because the the prothrombin (platelets) are being destroyed in this condition.

Answer 3

The PTT is done to monitor unfractionated Heparin anticoagulant therapy. When it is given in therapeutic doses, it must be closely monitored. If given too much, the patient may bleed excessively; too little and the patient may continue to clot.