Guidwires and Vascular Catheters

Question 1

Function and Construction of Guidwires

Answer 1

FUNCTION:
* To allow the safe introduction of the catheter into the vessel and selective positioning of catheters
within the vascular system.

CONSTRUCTION:
* Flexible tip
* introduced first into the blood vessel
* Rigid tail

Question 2

What are the two types of Guidewires

Answer 2

Solid Stainless Steel, Wrapped Guidewires

Question 3

What are the advantages and disadvantages of Solid Stainless Steel?

Answer 3

Advantage

Reduces:
1. Tip Flaring
2. Blood clotting
3. Abrasion
4. Danger or raveling

Disadvantage
1. Lack of versatility

Question 4

What are the advantages and disadvantages of Wrapped Guidewires?

Answer 4

Advantage

1. More versatile

Disadvantage
1. Can damage the vessel or catheter

Question 5

What are the components of a Guidewire?

Answer 5

1. CENTRAL CORE
   - Made of stainless steel or NITINOL (provides turn-for-turn torque control without compromising flexibility)
2. DISTAL FLEXIBLE SPRING COIL
   - Made up of platinum or tungsten (for enhanced
   fluoroscopic visualization)
3. OUTER COATING

• Usually made up of PTFE or teflon materials with
  Hydrophilic Coating (an ultra-ludicious hyrdophilic coatingwhich facilitates guidewire positioning and device delivery)

Question 6

What are the two types of Central Core?

Answer 6

Fixed and Movable Core

Question 7

Refers to the response of the guidewire or catheter to twisting and turning.

Answer 7

TORQUE

Question 8

• Also called torque vise or deflector handle
• Used to direct the guidewire towards the
  desired arterial branch

Answer 8

TORQUE DEVICE

Question 9

A Tip Configuration measured in length

Fixed - cm?
Movable - cm?

Answer 9

STRAIGHT TIP

Fixed - 3cm

Movable - 10=15cm

Question 10

A Tip Configuration measured in radius, about 3mm to 3cm .

Answer 10

J-Shaped Tip

Question 11

Short Guidewire Length and use

Answer 11

30-50cm

• Usually used for percutaneous or direct vascular punctures.

Question 12

Average Guidewire length and use

Answer 12

100-150

• For adults undergoing selective angiography

Question 13

Long Guidewires and use

Answer 13

260cm

• Used when Interchanging vascular catheters

Question 14

Diameters for guidewires

Answer 14

0.35mm or 0.052mm

Most common used for adults is 0.89 and 0.97mm

Question 15

It is readily visualized under fluoroscopy, which
facilitates catheter placement.

Answer 15

Radiopaque.

Question 16

_______ catheters are used for visualization
of air bubbles.

Answer 16

Radiolucent.

Question 17

The outer diameter of the catheter is most
commonly expressed in what?

Answer 17

French scale

Has an increment of
approximately 0.33 mm or 1⁄3 mm.

Question 18

The French number was developed by French instrument maker named?

Answer 18

Charrière.

Question 19

Smaller French sizes ( _ to _ ) are used for children.
Adults usually require about _ to _ Frec]nch catheter

Answer 19

3 to 6 for children
4 to 7 for adults

Question 20

Catheter shapes can be categorized into four basic shapes:

Answer 20

1.) Straight Tip
2.) Single Curve
3.) Double or multiple curve
4.) Pigtail

Question 21

Advantages of The combination of end
holes and side holes

Answer 21

Advantages:
1. Reduces trauma to the vessel
2. Enhances the mixing of contrast media with the blood.
3. It also reduces any recoil caused by jet-effect of a high-pressure injector.

Disadvantage:
1. There is an increase potential of
blood clotting using multiple holed
catheter.

Question 22

What are the other types of catheter?

Answer 22

Guiding Catheter – allow safer or more secure passage of devices into the vessel.

Microcatheter – placed through standard angiographic catheters to allow entry into small or tortuous arteries guided by small steerable guidewires.

Special catheters - for a variety of angiographic and
interventional procedure are also available such as
brockenbrough catheter, balloon catheter, and atherocath.