LARYNGECTOMY FAQ'S

Can radiation cause dizzy or fainting spells (vasovagal syncope)?
(by Glenn E. Peters M.D., Director, Division of Otolaryngology
Head and Neck Surgery, University of Alabama at Birmingham,
Birmingham, Alabama, USA)

Let’s start by reviewing some anatomy. Then, I will address the problem some patients have when they turn their heads and get a little dizzy and light headed. On either side of your neck is the carotid arteries which are the main suppliers of blood to the head and more specifically, the brain. This artery comes into the neck from the chest as a single large artery, the common carotid artery, then splits in the upper neck to become the external carotid artery supplying blood to the face and head outside of the skull and the internal carotid artery supplying blood to the brain. Where this artery splits is called the carotid bulb and you can usually feel it as a pulsating mass in the upper neck. The carotid artery and especially the carotid bulb are enervated by some specialized nerve fibers that are sensitive to the chemical content of the blood and also to the pressure of the blood inside of them.

Now, lets say you have had surgery on the neck or radiation to neck. Remember that either of these can cause some degree of scarring around this blood vessel resulting in some degree of "squeeze" on them. The nerves, that I mentioned above, read this as an increase in the pressure INSIDE of them and set in motion automatic measures to lower the blood pressure. These include a lowering of the heart rate and a dilatation of the blood vessels in the rest of the body. The net result of all of this is a relative lowering of the blood pressure to the brain and the sense of dizziness and being light headed. This whole thing can be made even worse if you have some degree of athersclerosis (cholesterol plaque)or if you are taking medicines for high blood pressure. Dehydration also may be a contributing factor.

If you have this problem, unfortunately there is not much that can be done to eliminate it. The most important thing is to simply be aware that the problem exists and not change positions rapidly, i.e. lying to sitting or sitting to standing. Take your time when you get up and don’t immediately start walking. You might want to make sure you are well hydrated and that your blood pressure is under good control and your anti-hypertensive medicine is right for you. If the problem is severe enough that you almost black out or if it occurs very frequently, please check with your doctor and make sure that you are not having transient ischemic attacks (mini strokes) or something wrong with the heart itself causing it to be an inefficient pump.