Trust Homepage > Pathology Homepage

Test and Tubes Database
Search Links: General Info : Protocols : Patient Info

DescriptionThe Activated Partial Thromboplastin Time (APTT) measures the activity of the intrinsic and common pathways of the coagulation cascade.
IndicationThe APTT is used as a part screen for the assessment of normal coagulation.It is also used in the monitoring of unfractionated heparin therapy with results usually being expressed as an APTT ratio (patients APTT in seconds / mid-point of the normal range).
Additional InfoUsually requested as part of a coagulation screen including a Prothrombin time and Fibrinogen level.Please note: test can only be added to samples within 24 hours of collection
Concurrent Tests
Dietary Requirementsnone

InterpretationReported as a time in seconds against a normal range. APTT ratios are reported with a suggested therapeutic range for control of unfractionated heparin.

Ref. Range (Male)23.5 - 37.5
Ref. Range (Female)23.5 - 37.5
Ref. Range (Paed)23.5 - 37.5
Ref. Range NotesCritical telephone values: APTT greater than 70 seconds (with no obvious cause) will be phoned to the ward/clinical area. If the patient is on unfractionated heparin, results will be phoned if the APTT ratio is greater than 5.0.

IP Acute TATRefer to Website
IP Routine TATRefer to Website
GP Acute TAT- Contact Laboratory
GP Routine TATRefer to Website
Turnround CommentNA
Originally edited by : RJAR. Last edited on 18/06/2019 10:28:51. Published By RJAR on 18/06/2018 10:28:51.