Module 8: Intraoperative Vascular Sonography

Question 1

When was the first application of intraoperative ultrasound? What was it used for?

Answer 1

First application was with A mode in 1961, it was used for renal stone localization

Question 2

What are some advantages to using ultrasound in the OR?

Answer 2

1. High resolution and real time localization
2. Reduce risk of complication/ damage during surgery
3. Doppler used to visualize vessels
4. No radiation
5. Information is instantaneous which reduces surgery time

Question 3

Where are some places we can use intraoperative ultrasound?

Answer 3

1. Neurosurgery
2. General vascular surgery
3. Parathyroid adenoma location
4. Intraperitoneal
5. Retroperitoneal

Question 4

What are some doppler studies performed in the OR?

Answer 4

1. Carotid endarterectomies
2. Transcranial doppler (TCD) for monitoring cerebral perfusion
3. Peripheral vein grafts
4. Intra-abdominal procedures such as renal artery or mesenteric artery reconstruction

Question 5

What is the role of the sonographer in the OR?

Answer 5

1. Clean machine and transducer
2. Optimize image
3. Vascular surgeon or radiologist handles probe
4. Radiologist interprets image in real time
5. Relays concerns to surgeon
6. Monitors the MCA during TCD

Question 6

What is the sterile technique used in the OR?

Answer 6

1. Probe and cord covered with a sterile sleeve and sterile gel is used
2. Can require two people

Question 7

What is the PPE to don in the OR?

Answer 7

1. Surgical scrubs
2. Hair and shoe coverings
3. Mask
4. All rings removed from hands

Question 8

What is TCD (transcranial doppler) used?

Answer 8

1. Carotid endarterectomy
2. Open heart surgery with bypass
3. Monitoring of intensive care patients

Question 9

What are some benefits of TCD?

Answer 9

1. Gives information in real time
2. Can tell if hemodynamics are altered to brain
3. Ca change therapy if indicated

Question 10

What MCA velocity shows adequate collateral circulation?

Answer 10

> 10 cm/sec

Question 11

MCA is monitored during procedure to do what?

Answer 11

Predict microembolization
1. Predicts postoperative stroke
2. Can change surgical techniques

Question 12

In most cases during TCD the M1 segment of the MCA is what?

Answer 12

Insonated at a depth of 50 - 55 mm

Question 13

What can the sonographer do for open heart surgery?

Answer 13

1. Monitor for brain damage and perioperative stroke (hypoperfusion/ hyperperfusion)
2. Detect air micro emboli
3. Detect for loss of cerebral autoregulation

Question 14

Frequency of Micro emboli detected during surgery correlates with degree of what?

Answer 14

Neuropsychological deficit

Question 15

What kind of patients does sonographers do for ICU monitoring of cranial injuries?

Answer 15

For patients with increased increased intracranial pressure and severe cerebrovascular disease, also with hydrocephalus.

Question 16

What are some patient conditions we scan in the ICU?

Answer 16

Patients with
1. Extracranial occlusive disease
2. Heart failure
3. Valvular disease
4. Impending brain death

Question 17

For patients with Lower extremity bypass grafting what can we do?

Answer 17

Duplex assessment during
1. Angioplasty
2. Bypass

Question 18

What is the gold standard for Lower extremity bypass grafting?

Answer 18

Angiography

Question 19

What are some LE bypass grafting complications?

Answer 19

1. Stenosis
2. Vein webs
3. Retained valve cusps
4. Plaque dissection
5. Focal platelet aggregation

Question 20

What is the major concern for artery reconstruction in which we monitor?

Answer 20

Hemodynamic success of the procedure to ensure organ preservation

Question 21

What some artery reconstructions?

Answer 21

Renal and mesenteric arteries