Mosby's Exam Review for Computed Tomography – Simulated Exam with Well Explained Answer Rationales (Patient Care, Safety, Procedures, Image Production)

Mosby's Exam Review for Computed Tomography – Simulated Exam with Well Explained Answer Rationales (Patient Care, Safety, Procedures, Image Production) An average range for activated partial thromboplastin time (PTT) is: a) 10-12 seconds b) 17-21 seconds c) 25-35 seconds d) 43-55 seconds - ANS: C) 25-35 seconds Partial thromboplastin time (PTT) is a lab measure of blood coagulation. This value is used to screen patients for invasive procedures. BC of the individual lab practices, the average range may fluctuate slightly. Which of the following is the correct angle of insertion for placing a butterfly needle into a vein for intravenous administration of a contrast agent? a) 5 degrees b) 15 degrees c) 45 degrees d) 60 degrees - ANS: B) 15 degrees A butterfly needle should be inserted at an angle of 15 degrees for the intravenous administration of contrast material. A total volume of 125 mL of iodinated contrast agent is administered intravenously via automatic injector in 50 seconds. The flow rate for this injection is: a) 0.75 mL/sec b) 1.24 mL/sec c) 1.75 mL/sec d) 2.5 mL/sec - ANS: D) 2.5 mL/sec The flow rate may be calculated by dividing the total contrast volume by the time of the injection. In this example, the total contrast volume is 125 mL and the time for the injection is 50 seconds. The flow rate programmed for this injection would be 125 divided by 50, or 2.5 mL per second. The condition whereby the patient suffers from a low concentration of oxygen in the blood is called: