Specimen

3 mL Whole blood in 1 Blue Top (Sodium Citrate) tube. Mix thoroughly by inversion. Transport to Lab within 4 hours. If this is not possible, make PPP within 1 hour of collection as follows: Centrifuge sample at 3600 rpm fo 15 min.& transfer supernatant to a clean plastic tube. Centrifuge this supernatant again at 3600 rpm for 15 min. & finally transfer the supernatant (PPP) to 1 labelled clean plastic screw capped vial. FREEZE IMMEDIATELY. Ship frozen. DO NOT THAW. Overnight fasting is preferred. Duly filled Coagulation Requisition Form (Form 15) is mandatory.

Usage

APTT measures intrinsic and common pathways of the coagulation cascade. Prolonged APTT may be caused by heparin and other anticoagulants, factor deficiencies or inhibitors such as lupus anticoagulants.