Epic Code LAB325 APTT
Test Name Alias
Activated Partial Thromboplastin Time | PTT | 8450
Interface Order Alias
10055
Clinical Information
The activated partial thromboplastin time is a measurement of the activity of the factors involved in the intrinsic and common pathways of coagulation. The APTT is also used to monitor unfractionated heparin therapy. Prolonged APTT may occur in the following: Inherited factor deficiencies, anticoagulant therapy, vitamin K deficiency, liver disease, circulating anticoagulants, lupus inhibitors, factor inhibitors, or consumption of fibrinogen or other coagulation factors in DIC.
Icons & Photos
Collection Instructions
Specimen Collection: Blood
Container(s): 3.2% Na Citrate Tube (blue top)
Preferred Volume to Collect: 2.7 mL (full tube)
Minimum Volume to Collect: 1.8 mL (full tube)
Capillary collect ok: No
Microtainer acceptable: No
Collection Instructions:
-
Detailed instructions (link): Anticoagulant Correction for High Hematocrit
-
Detailed instructions (link): Blue Citrate Tube
- Specimen should be processed within 4 hours – See Processing Instructions below.
- Specimens collected from patients receiving heparin therapy must be processed within 1 hour – See Processing Instructions below.
Processing Instructions (Laboratory, Outpatient or Off-site collection)
Processed Specimen: Platelet Poor Plasma
Centrifuge/Spin: Yes
Aliquot: Yes
Processing Instructions:
- Detailed instructions (link): Preparing Platelet Poor Plasma
- Separate plasma into 1 – 2 aliquots, minimum of 0.5 mL each.
- Freeze aliquots in plastic transport tubes immediately.
Transport Temperature:
- Ambient (up to 4 hours in whole blood state, 1 hour for patients on heparin therapy)
- Frozen (plasma only >4 hours)
Rejection Criteria
- Hemolysis
- Specimen has been thawed
Specimen Stability
Ambient: up to 4 hours in whole blood state if the patient is not on heparin
Refrigerate: Not Acceptable
Frozen: Aliquot and freeze platelet poor plasma within 1 hour of collection if the patient is on heparin. Also freeze if >4 hours post collection plasma.
Laboratory Retention: 24 hours
Test Frequency
Available 24 hours, usual TAT 1 day.
Reference Range
- 21 - 27 seconds (Spectrum Health Regional Lab, Grand Rapids - BCS XP analyzer)
- 21 - 31 seconds (Spectrum Health Regional Lab, Grand Rapids - CS 5100 analyzer)
- 21 - 31 seconds (Spectrum Health Regional Hopsital Labs including Blodgett, Big Rapids, Gerber, Kelsey, Ludington, Pennock, Reed City, United and Zeeland)
High and Reduced intensity anticoagulation therapeutic range: 42 - 57 seconds. See individual nomograms for therapeutic ranges for other indications.
Performing Department
COAGULATION
Performing Department Laboratory Location
Spectrum Health Regional Laboratory, Grand Rapids, MI
Regional Hospital Labs:
Spectrum Health Big Rapids Laboratory, Big Rapids, MI
Spectrum Health Blodgett Laboratory, Grand Rapids, MI
Spectrum Health Gerber Laboratory, Fremont, MI
Spectrum Health Kelsey Laboratory, Lakeview, MI
Spectrum Health Ludington Laboratory, Ludington, MI
Spectrum Health Pennock Laboratory, Hastings, MI
Spectrum Health Reed City Laboratory, Reed City, MI
Spectrum Health United Laboratory, Greenville, MI
Spectrum Health Zeeland Laboratory, Zeeland, MI
Methodology
Clot-based assay
CPT
85730
CDM Code
80101963
Epic Test ID
1230100362
LOINC
APTT: 14979-9
Beaker LOINC
APTT NO CLOT DETECTED: N/A
APTT: 14979-9
Mayo Access Code
SHO8450
Reviewed Date
10/11/2021
Beaker Names
Beaker Procedure Name: APTT
Beaker Display Name: Activated Partial Thromboplastin Time (APTT)
BEAKER TEST NAME: APTT
BEAKER TEST REPORT NAME: APTT
Beaker Synonyms
No synonym on file
Beaker Collection and Specimen Handling
BEAKER COLLECTION: +(1)S10/PO/F
Beaker Location, Container and Temperature
BW COAGULATION: BLUE TOP TUBE (Preferred)
BL COAGULATION: BLUE TOP TUBE (Preferred)
BR COAGULATION: BLUE TOP TUBE (Preferred)
GM COAGULATION: BLUE TOP TUBE (Preferred)
KL COAGULATION: BLUE TOP TUBE (Preferred)
LH COAGULATION: BLUE TOP TUBE (Preferred)
PH COAGULATION: BLUE TOP TUBE (Preferred)
RC COAGULATION: BLUE TOP TUBE (Preferred)
UN COAGULATION: BLUE TOP TUBE (Preferred)
ZH COAGULATION: BLUE TOP TUBE (Preferred)