3.2 Carotid Endarterectomy

Question 1

Describe the course of the Carotid Artery

Origins

Answer 1

Right common CA ← Brachiocephalic artery
Enters neck deep to omohyoid

Left common CA ← direct Arch
Medial phrenic + Vagus N.

Question 2

Carotid Artery path

Answer 2

Arteries ascend from thorax
within carotid sheath

Between RLN (M) + Vagus (L)

Along with IJV (L)

Cervical sympathetic trunk lies posterior and external to sheath

Question 3

Divisions

Answer 3

@ C4 (upper thyroid cartilage border)

Divides
External + Internal

Carotid sinus located at bifurcation
Baroreceptors - Stretch - BP reg

Carotid Body - Chemoreceptors - Ventilation

Question 4

External Carotid Branch ECA

Path

Answer 4

Supplies upper Neck + Face

• ascends through neck & parotid gland

Ends behind neck of mandible
- dividing into Maxillary + superficial temporal A.

In neck lies deep SternoCM
on lateral wall pharynx

Initially anteromedial to ICA
Moves lateral to it
w/ Glossopharyngeal N.
Branches of Vagus N between walls

Ends in parotid gland

Question 5

Eight branches ECA

Answer 5

1. Superficial Thyroid
2. Ascending pharyngeal
3. Lingual
4. Facial
5. Maxillary
6. Occipital
7. posterior Auricular
8. Superficial temporal

Question 6

ICA

Answer 6

Supplies Orbit + Majority arterial Brain supply

No neck branches

Initially lateral to ECA
Moves behind IJV

Middle cranial fossa via
Foramen Lacerum
+
Carotid Canal

Terminal bifurcation
Anterior Perforated substance
into
ACA
MCA Continuing main body

Question 7

ICA Divides into 3 portions

Answer 7

Petrosal
- Within carotid canal
- Petrous temporal bone

Cavernous
- Passes through cavernous sinus

Branches trigeminal ganglion

Supraclinoid
Intracranial branches
-Ophthalmic
P.Comm
Striate
Anterior choroidal

Question 8

General Anaesthetic vs Local Anaesthetic

GA

Advantages

Answer 8

Secure airway

Controlled ventilation

↓ CMRO2
-induction + maintenance
agents

Manipulation of temperature

No Time contraints

Question 9

GA Enadarterecomy
disadvantages

Answer 9

CVS complications
Intubation and induction

Unconscious - alternative cerebral flow monitoring
Labour + operator dependent

↑ use of shunts
a/w ↑ post op neuro dysfunction

Difficulty assessing neuro function postop
residual effect GA / Analgesia

Question 10

Regional
Advantages

Answer 10

Allows continual assessment neuro fxn
- early detection potential ischaemia

Earlier post op assessment

↓ Shunting incidence

↓ BP fluctuation and potential cardiac events

Question 11

Regional
Disadvantages

Answer 11

1 Patient Co-Operation required

2 Surgical team happy w/ awake patient

3 Patient often restless lying still

4 Shiver if cold

5 Cough

6 Passing urine

7 Claustrophobia with drapes

8 Unsecured airway

9 Block complications
- phrenic + RLN block
- Horner’s
- Total spinal
- Nerve trunk injury
- LAST

GALA trial in 08
- no difference in primary outcomes