Let's talk about Raynaud's
that's a related thing in which there is spasm
in the artery. So let's look at the definition,
and we'll start with a case, as we often do.
Here's an 18-year-old man, and he complains
of severe pain in the tips of his fingers
and toes, especially when dealing with cold
materials. You'll notice that that's similar
to what is seen also in the Buerger's patients.
He states that after working in the cold,
he develops discolorations of his fingers,
progressing from white to blue. And you can
see that in the picture on the left and the
right. And then when he puts his hands in
warm water or warms them up, then color is
restored. Usually, the fingertips are bright
red for a while and then go back to normal
Now, the definition of Raynaud's actually
falls into three different forms of Raynaud's.
Some people have Raynaud's as a disease. In
the… You see there in the middle area…
in the middle box. This actually… The reason
for it is unknown. It occurs in some people
where they are just born very sensitive to
cold, and they repeatedly get this symptom.
And in fact, in Arizona, where I live, I've
seen a number of patients who have so-called
primary Raynaud's, and they'd moved to Arizona
because they couldn't stand living in the
northern United States. When the cold weather
came on, they were constantly in pain in their
hands. On the other hand, you can see it as
a phenomenon—a transient phenomenon—that
occurs often in the setting of systemic disease
like systemic lupus erythematosus or rheumatoid
arthritis. Any autoimmune disease can lead
to some secondary occasional Raynaud's that's
usually not quite so bad, although again,
sometimes it can be severe enough that people
have to move to a warm climate. And finally,
there is the syndrome which occurs in people
who know that a certain set of circumstances—for
example, emotional stress, will bring on
Raynaud's. So the two on either side are secondary
to another condition, whereas the primary
one can occur and can be inherited and actually
is not treatable.
Let's talk about the pathogenesis. It's due
to a vascular abnormality. The endothelium
(remember, that little tiny layer on the inside
of the blood vessel?): It produces a number
of substances that keep the vessels dilated.
And often, in the setting of Raynaud's phenomena
or disease, there's a deficiency of these
vasodilating substances. One of the most common
is called nitric oxide. When that happens
(that there's a deficiency), the blood vessel
can spasm and close down and cause the white
area that you saw from lack of blood flow.
And then when the hand warms, there's a redness
as the blood rushes back into the area where
the vasospasm had occurred.
There are often abnormalities in the autonomic
nervous system, as we talked about. There's
often repeated periods during stress where
the noradrenaline or norepinephrine that's
released at the nerve endings causes spasm
of the blood vessels. And you can even have
little clots forming because of the spasm.
And also, there's increased activation of
the clotting system; the platelets can aggregate.
And with the production of increased platelet
thromboxane, which is a vasoconstricting compound,
you can also make this worse. So there's a
whole cascade of things that can happen, starting
with a vascular abnormality, going on to a
neural abnormality, and then eventually adding
in with some floating substances in the bloodstream
from the platelets that make things even worse.