The Terminology- SNOMED CTÂ®, an Evolving Clinical Reference Terminology. SNOMEDÂ® is the Systemized Nomenclature of Medicine. It is a controlled medical terminology (CMT). At its simplest, a SNOMED is a coded vocabulary of medical concepts and expressions used in healthcare.
The partial thromboplastin time (PTT) is a screening test that helps evaluate a person's ability to appropriately form blood clots. It measures the number of seconds it takes for a clot to form in a person's sample of blood after substances (reagents) are added.
Youâd also need this test if you get heparin therapy -- thatâs a medicine used to prevent or treat blood clots after youâve had an issue like a heart attack or stroke. The PTT test helps make sure you get the right dose. You want to prevent dangerous clots, but still let your blood clot when you need it to. You may also get the test to: