Chapter 12 & 13

Viscosity

____________ is a physical property that may be described as the thickness or friction of the fluid as it flows.

Contrast agents

________________ fill a structure with a material that has a different density than that of the structure.

Bolus

The three general phases of tissue enhancement commonly discussed in CT are the ____________ phase, the nonequilibrium phase, and the equilibrium phase.

False

True or False? Accessing and de-accessing an implanted port is the job of the CT technologist.

A. 1.5 to 2 mL/s

What is the rate at which most CVCs are infused?

A. 1.5 to 2 mL/s

B. 0.5 to 1 mL/s

C. 1 to 1.5 mL/s

D. 2 to 2.5 mL/s

C. 2 to 3 minutes

If a tourniquet is removed because it has been on the arm too long causing the skin to mottle, how long should you allow for circulation to return before you reapply the tourniquet?

A. 7-10 minutes

B. 5-7 minutes

C. 2-3 minutes

D. 30 seconds to 1 minute

Body Temperature

Contrast viscosity can be dramatically reduced, in some cases by nearly half, by simply warming contrast to _________________.

D. arterial phase

What is another name for the bolus phase of tissue enhancement?

A. venous phase

B. aortic phase

C. nonangiographic phase

D. arterial phase

C. bolus shaping

Which is not a name for the method of individualizing the scan delay using the contrast bolus itself to initiate the scan?

A. bolus tracking

B. bolus triggering

C. bolus shaping

D. automated triggering

False

True or False? If the vein selected for placement does not adequately distend with the tourniquet, place a second tourniquet just below the first and hang the arm below the level of the patient's heart.

Drip infusion

The two methods of administering contrast material are the _________ technique and the bolus technique.

True

True or False? Many PICC lines cannot tolerate the pressure required to inject contrast media at the high injection rates typical of CT examinations that use mechanical injectors.

B. Pharmacokinetic

Which factors that affect the degree of contrast enhancement in human tissue are largely controllable by the technologist?

A. patient

B. pharmacokinetic

C. equipment

A. manipulating the flow rate to change the characteristics of the time-density.

What is bolus shaping?

A. manipulating the flow rate to change the characteristics of the time-density

B. injecting a higher concentration agent to deliver the same amount of iodine at a lower flow rate

C. the ability to perform a saline test injection before the delivery of contrast bolus injections

D. the interval between the initiation of the injection and the start of scanning

B. venous phase

What is another name for the nonequilibrium phase of tissue enhancement?

A. nonangiographic phase

B. venous phase

C. arterial phase

D. aortic phase

False

True or False? Central venous access devices (CVADs) are the optimal choice for contrast administration.

D. scan delay can be precisely controlled

Which is not an advantage of the hand bolus method?

A. it does not require any special equipment to implement

B. it is relatively inexpensive

C. it allows the injection site to be closely observed so that the injection can be immediately stopped should there be signs of extravasation of contrast into the soft tissue

D. scan delay can be precisely controlled

A. peripherally inserted central catheter

Which is the name for a long catheter that is inserted through the large veins of the upper arm?

A. peripherally inserted central catheter

B. central venous catheter

C. midline catheter

A. antecubital or large forearm vein

Which is the preferred venous access site when a mechanical injector is used?

A. antecubital or large forearm vein

B. cephalic vein

C. superficial dorsal vein

D. axillary vein

Equilibrium or delayed

The _____________ phase is the worst phase of tissue enhancement for acquiring scans of the body, particularly the liver.

True

True or False? Manufacturers label the external portion of catheters by printing its size and type on the catheter hub or external tubing.

False

True or False? Tumors and other disease processes always have different attenuation coefficients than those of their surrounding tissue.

Attenuation

Adjacent tissues must have different _______________ to be distinguishable on a CT image.

Osmolality

_______________ is a property of intravascular contrast media that refers to the number of particles in solution, per unit liquid, as compared with blood.

C. 3 mL/s or higher

For what flow rate is a 20-gauge or larger catheter preferable?

A. 4 mL/s or higher

B. 5 mL/s or higher

C. 3 mL/s or higher

D. 6 mL/s or higher

B. Ports

Which type of CVC has the lowest incidence of infection?

A. tunneled catheters

B. ports

C. non-tunneled catheters

C. mechanical injection system

Which method of contrast media injection is programmable for uniphasic, biphasic, or multiphasic injection protocol?

A. hand bolus

B. drip infusion

C. mechanical injection system

A. dorsal

Which is not a vein in which a non-tunneled central catheter is inserted?

A. dorsal

B. subclavian

C. jugular

D. femoral

B. median cubital vein

Which is not a superficial vein of the hand?

A. dorsal digit vein

B. median cubital vein

C. dorsal venous arch

D. cephalic vein

C. it is secure and easy to access

Why is the tunneled catheter the best choice when access to the vein is needed for long periods of time and when the line will be used many times each day?

A. it is less expensive

B. it is lighter in weight than a PICC line

C. it is secure and easy to access

D. it is easier to insert than a non-tunneled catheter