PTT

Mnemonic

PTT

Synonym

ACTIVATED PARTIAL THROMBOPLASTIN TIME, Partial Thromboplastin Time - APTT -aPTT

Specimen Collection Requirements

Collect

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

Handling

DO NOT refrigerate. See Coagulation Specimen Collection Guidelines. For more information

Preferred Volume

If frozen, 1.0 mL aliquot

Minimum Volume

If frozen, 0.5 mL aliquot

Transport

Ambient (within hospital)/frozen via courier

Rejection Criteria

Clotted samples, samples collected in containers other than 3.2% Buffered Sodium Citrate, tubes filled less than 90%, over-filled tubes, samples from patients with a Hematocrit greater than 55% (if abnormal), hemolyzed samples due to ex-vivo causes (i.e., difficult draw, poor sample draw). 

Stability

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

Testing Information

Performed

All SHS locations, 24/7

Method

Stago Compact

Referral Lab

Samaritan Health Services Laboratories

Reference Values

Reference Values

24.0-35.0 seconds

Critical Values

>120 seconds

Therapeutic Range

50-85 seconds

CPT Codes

87530

Last Updated: Friday, April 24, 2020 11:33:12 AM