Open Carotid Surgery was first performed more than 50 years ago to prevent stroke.
The carotid artery begins in the chest, passes up to the neck where it divides into the internal and external carotid arteries. The internal carotid passes up to the brain while the external supplies the structures of the face and scalp. The internal is the important branch. Where the artery divides is predisposed to narrow or stenose. This is caused by a local flow disturbance and other risk factors (i.e. diet, cigarette smoking, etc.) that allow cholesterol plaque to build up in the lining of the vessel. The process is termed atherosclerosis or hardening of the arteries. The plaque is irregular unlike the normal smooth normal artery. This narrows the flow channel and presents a diseased surface upon which blood clots may form. These can then dislodge and travel through the circulation to block smaller vessels in the eye or brain. If the blockage is temporary then that part of the brain stops working for some minutes, this is termed a T.I.A. It may manifest as sudden weakness in the arm, leg or face, temporary visual loss in one eye or speech difficulty. If however the clot permanently blocks the vessel, then that part of the brain dies and that function is lost partially or permanently – this is a stroke.
Carotid Surgery aims to surgically remove the diseased lining of the artery in a process called endarterectomy and leave it smooth with normal flow. The operation is performed under general anaesthetic with a painless incision in the neck over 10 cm. The carotid artery is exposed, clamped and a temporary shunt inserted so that the blood supply to the brain is not interrupted. After the plaque has been removed a patch is sewn in to reduce the chance of the artery re-narrowing, then the shunt is removed. A drain is placed in the wound, the sutures dissolve.
Possible complications of surgery:
- While the operation reduces the long term overall risk of stroke, it doesn’t eliminate it. There is a 1-5 % risk of stroke within the first 2 days and a 0.5% risk annually thereafter.
- There are a number of cranial nerves around the carotid artery that may need to be handled or moved out of the way to facilitate the surgery. These supply the tongue, the voice box and the back of the throat. If handled they may temporarily stop working for days to weeks afterwards. There is a 1/100 risk of permanent damage to them. If this occurs then the tongue may wither, the voice may become hoarse or the act of transferring food into the back of the throat may be impaired.
- In any vascular procedure there is a small risk of bleeding, this may require returning to the operating theatre to control it. The risk of wound infection is very low in the neck but present.
Information has been derived from the patient education pamphlet “Carotid Endarterectomy and Angioplasty with Stenting”, Royal Australasian College of Surgeons and published by Mi-tec Medical Publishing. The complete pamphlet is available from our rooms.