Second Subject: Specimen Collection
Description
Which of the following test procedures cannot be performed on specimens collected by skin puncture?
a. bilirubin
b. calcium
c. partial thromboplastin time (PTT)
d. T3
- Partial thromboplastin times (PTT) are characteristically performed on plasma specimens collected by venipuncture. Specimens for coagulation studies requiring plasma samples may not be collected by skin puncture. Some manufacturers supply light blue top micro-collection containers but these are intended to use following a syringe draw not following skin puncture.
