D-dimer blood test review for nursing students!
This quick review will highlight the main concepts you need to know about a D-dimer lab test. As a nurse you want to be familiar with this blood test because it can help the physician determine if a patient may have a blood clot.
Quick Lecture on the D-dimer
D-dimer Blood Test
What’s a D-dimer?
A D-dimer, also called fibrin degradation fragment, is a blood test that assesses for fibrin degradation fragment, which is a fibrin degradation product.
What is fibrin degradation fragment? This is a protein fragment that hangs out in the blood when a clot breaks down. So, this means a clot has formed and has started to break down.
What does a D-dimer help diagnose? It’s used to diagnose blood clots or Disseminated Intravascular Coagulation (DIC).
Shortcomings of a D-dimer? A D-dimer doesn’t tell us where the clot is located, so it will need to be further investigated by the MD. Also, a positive result doesn’t necessarily mean the patient has a clot because some disease processes can cause a false positive, as given in the example below:
- Example: Liver disease, MI, surgery (heart), cancer, pregnancy etc.
What’s a normal D-dimer? A D-dimer result can be reported in either fibrinogen equivalent units (FEU) or d-dimer units (DDU). Always note how your lab is reporting the cut-off.
- Normal level: <500 ng/mL FEU or <250 ng/mL DDU
You may be interested in Deep Vein Thrombosis Review.
References:
Diagnosis and Treatment of Venous Thromboembolism | CDC. (2019). Retrieved 1 November 2019, from https://www.cdc.gov/ncbddd/dvt/diagnosis-treatment.html