ACTIVATED PARTIAL THROMBOPLASTIN TIME

Mnemonic

PTT

Synonym

Partial Thromboplastin Time - APTT - PTT - aPTT

Specimen Collection Requirements

Collect

One light blue (3.2% Buffered Sodium Citrate) top tube

Handling

Coagulation Specimen Collection Guidelines

Preferred Volume

Two 1.0 mL aliquots

Minimum Volume

One 1.0 mL aliquot

Transport

Ambient (20-28°C)

Rejection Criteria

Clotted samples; samples collected in containers other than 3.2% Buffered Sodium Citrate; tubes filled less than 90%; samples from patients with a Hematocrit greater than 55%; hemolyzed samples due to ex-vivo causes (i.e., difficult draw, poor sample draw); whole blood samples that were frozen before processing

Stability

WHOLE BLOOD Ambient: 4 hours. PLASMA Ambient: 4 hours; Frozen: -20°C 2 weeks, -70°C 6 months

Testing Information

Performed

7 days/week

Method

Clotting

Referral Lab

Samaritan Health Services Laboratories

Reference Values

Reference Values

Varies, see report.

Critical Values

>120 seconds

CPT Codes

85730

Last Updated: Thursday, January 5, 2017 03:41:55 AM