Arterial Lines

Question 1

Purposes of an A-line?

Answer 1

1. Provide real time beat-to-beat blood pressure
2. Drawing labs

Question 2

Pressure transducer system materials

Answer 2

1. 500ml bag normal saline
2. Arterial line (non-compliant) tubing that contains a pressure transducer
3. Pressure transducer cable (Arterial line cable)
4. Pressure bag for 500ml N/S
5. Transducer holder

Question 3

How to flush the arterial line

Answer 3

Noncompliant arterial line tubing is flushed by opening the roller clamp and compressing the two “doodads” on the transducer

Question 4

What are some reasons that an Arterial line won’t flush?

Answer 4

1. The stopcocks could be turned off to the line
2. The pressure bag could be “under-pressurized”
3. The roller clamp on the arterial line tubing could be closed
4. The arterial line catheter could be clotted off (in which case we can try to aspirate the clot out with a syringe)

Question 5

Setting up the Arterial line

Answer 5

1. Spike the 500ml N/S bag with non-compliant tubing and place inside pressure bag
   - Inflate to 300mmHg
2. Flush all of the air out of the non-compliant tubing
3. Connect transducer cable to the transducer and the monitor
4. “Zero” the Arterial line

Question 6

Steps to “zeroing” the Arterial line

Answer 6

1. Change the monitor (from “Standard”) to a screen that will show an arterial line tracing (i.e. “8 Wave”)
2. Turn the stopcock nearest to the transducer OFF TO THE PATIENT, OPEN TO AIR (which means the stopcock cap must be removed)
3. Touch where the ABP reading is and push “zero” on the monitor
4. After the monitor shows a 0, turn the stopcock off to the atmosphere again, THEN put cap back on stopcock

Question 7

Materials for cannulating the artery

Answer 7

Question 8

What are the two catheter options for cannulating?

Answer 8

Question 9

Two options for extending the wrist?

Answer 9

Question 10

Steps to Arterial line placement

Answer 10

1. Set up the A-line and zero the transducer
2. Position and prep the wrist with chloraprep
3. Numb the area with lidocaine (if patient is awake)
4. Puncture artery and advance the catheter
5. Remove the needle and hook up the catheter to the flushed non-compliant tubing
6. Secure the catheter with tegaderm and tape

Question 11

What does the upstroke on the waveform indicate?

Answer 11

Question 12

What does the downstroke on the waveform indicate?

Answer 12

Question 13

What does the dichrotic notch on the waveform indicate?

Answer 13

During diastole, it is the blood slamming back down into the aortic valve

Question 14

Difference between sluggish and steep upstrokes and downstrokes in waveform

Answer 14

Question 15

Causes of overdampening of the waveform

Answer 15

1. Compliance in tubing
2. Partially clotted catheter
3. Kinked catheter from flexed wrist
4. Low pressure in system
5. Air bubbles

Question 16

Ways to fix a dampened waveform?

Answer 16

1. Try to aspirate blood or flush the tubing
2. Try extending the wrist
3. Make sure system is pressurized to 300mmHg
4. Look for air and aspirate any air bubbles

Question 17

An underdampened waveform leads to?

Answer 17

1. An overestimation of systolic BP
2. An underestimation of diastolic BP
3. MAP is essentially unchanged

Question 18

Causes of an underdampened waveform?

Answer 18

1. Deffective transducer
2. Tachycardia
3. Long tubing
4. Movement of the catheter in the artery
5. A catheter that is too large for the artery
6. Increased vascular resistance

Question 19

What is the natural frequency of an arterial line setup?

Answer 19

Question 20

What is the fundamental frequency of the arterial line system?

Answer 20

Question 21

What is a high, low, and optimal damping coeffecient?

Answer 21

Question 22

Femoral arterial line placement

Answer 22

Question 23

What are some arterial line complications?

Answer 23

1. Limb ischemia
2. Neurologic injury
3. Infection
4. Hemorrhage
5. Misinterpretation of data

Question 24

Where is the phlebostatic access?

Answer 24