Test Code PTTH Partial Thromboplastin Time, Heparin Protocol
EHR Test Codes
| Test Code | Test Name | |
| Atlas | PTTH | PTT, Heparin Protocol |
| Cerner | Partial Thromboplastin Time, Heparin Protocol |
Specimen Requirements
Preparation of Patient:
None
Container Type:
Light Blue Top 3.2% Sodium Citrate Tube 4.5 mL, 3.0 mL, 2.7 mL, 2.0 mL, or 1.8 mL
Specimen Type:
Plasma platelet poor
Specimen Volume:
Fill tube completely. Less than 90% filled tubes will be rejected.
Special Instructions:
For patients who are difficult access, < 1 year, and/or have a hematocrit > 55.9%; special tubes with an adjusted amount of anticoagulant can be prepared to allow for proper blood/anticoagulant ratio for accurate testing. Call the Hematology lab at 231-935-6118 to request special tube.
Specimen Handling/Transport:
Do not centrifuge. Do not refrigerate. Deliver to laboratory immediately.
Transport ambient room temperature.
Special Instructions:
If a specimen cannot be tested within 2 hours of draw, plasma should be removed from the cells and preserved as follows: Spin in a centrifuge verified for platelet-poor plasma preparation, remove plasma to a plastic tube, spin the plasma a second time, then remove plasma to a screw-top plastic tube and freeze immediately at -20° C. Transport frozen.
Specimen Storage/Stability:
Whole blood ambient room temperature 2 hours.
Double spun plasma aliquot ambient room temperature 1 hours.
Double spun plasma aliquot frozen -20° C 14 days.
Specimen Rejection:
Less than 90% filled tubes
Hemolysis
Clotted
Performing Laboratory
Munson Healthcare Laboratories
Priority, Frequency, & Turnaround
Priority:
Timed
Frequency:
24 hours 7 days a week
Turnaround:
60 minute from receipt in lab
Methodology
Electromagnetic Mechanical Clot Detection System
Reporting
Reference Range:
24 -36 sec
Critical Decision:
0 years to 21 years ≥ 65 sec
21 years and up ≥ 150 sec
Note: Critical values are called to the provider and communicated as critical. Documentation of the call is recorded in the patient record.
Clinical Significance
The aPTT is useful in monitoring heparin therapy.
CPT Code(s)
85730