Laboratory Medicine

Test catalogue

aPTT 50/50 Mixing Studies
Test Name aPTT 50/50 Mixing Studies (aPTT 1:1 , aPTT 50/50)
Specimen Type / Requirements Container Type = Blue (Sodium Citrate) Minimum Testing Volume = Full draw 9:1 Ratio (9 parts blood to 1 part anticoagulant)
Specimen Handling Collection Instructions: Must indicate anticoagulant status to avoid delay. Write your initials, date and time of collection on the collection label. Transportation: In/Outpatients: Send whole citrated blood at room temperature as soon as possible. Referred-in: Send frozen citrated plasma on dry ice. All samples must be sent to the Core Laboratory. Stability: Specimens are stable for 4 hours post collection at room temperature. Specimens which are not tested within 4 hours can be double-spun to remove the citrated plasma. The citrated plasma is stable at -20°C for up to two weeks or -70°C for up to six months. Sample Rejection Criteria: Clotted sample, grossly hemolyzed samples, Unlabeled or samples with insufficient quantity will be rejected.
Required Documentation
Turnaround Time (TAT) 1 day	Test Utilization
Reference Value Correction: < 4.0 seconds difference between aPTT 50/50 mix and aPTT control
Test Code PTT50	Methodology Clotting Assay
Testing Location SMH-Routine Coagulation	Other information Last Updated: June 06, 2019

aPTT 50/50 Mixing Studies

Test Name

aPTT 50/50 Mixing Studies (aPTT 1:1 , aPTT 50/50)

Specimen Type / Requirements

Container Type = Blue (Sodium Citrate)

Minimum Testing Volume = Full draw

9:1 Ratio (9 parts blood to 1 part anticoagulant)

Specimen Handling

Collection Instructions: Must indicate anticoagulant status to avoid delay.

Write your initials, date and time of collection on the collection label.

Transportation: In/Outpatients: Send whole citrated blood at room temperature as soon as possible. Referred-in: Send frozen citrated plasma on dry ice. All samples must be sent to the Core Laboratory.

Stability: Specimens are stable for 4 hours post collection at room temperature. Specimens which are not tested within 4 hours can be double-spun to remove the citrated plasma. The citrated plasma is stable at -20°C for up to two weeks or -70°C for up to six months.

Sample Rejection Criteria: Clotted sample, grossly hemolyzed samples, Unlabeled or samples with insufficient quantity will be rejected.

Required Documentation

Turnaround Time (TAT)

1 day

Test Utilization

Reference Value

Correction: < 4.0 seconds difference between aPTT 50/50 mix and aPTT control

Test Code

PTT50

Methodology

Clotting Assay

Testing Location

SMH-Routine Coagulation

Other information

Last Updated: June 06, 2019