Ischemia results when the
blood flow is cut off from
tissue. In ischemia's early stages, the arm or leg feels like it has "fallen asleep", and the
patient may feel
tingly or
numbness, and, if left untreated, will lose feeling and
mobility in the
limb. If ischemia continues, it results in the
death of that tissue. Anything that stops blood flow from a certain area can result in ischemia. This could be a severe
laceration to the wrist, a
splint set too tight, or something as simple as having a leg or arm bent in a direction that pinches off the blood flow. This happens more often than not at night while a person is sleeping, or while sitting in an awkward position for a long period of time.
Obviously, there are many varieties of ischemia.
Mesenteric ischemia is a condition in which the mesenteric arteries do not deliver enough blood and oxygen to the small and large
intestines. This makes it difficult for the intestines to
digest food and can cause segments of the intestine to die.
Myocardial ischemia, caused by a narrowing of arteries, is the most common form of
heart disease, affecting hundreds of thousands of Americans each year.
Cerebral ischemia often leads to a
stroke.
How and when to check for ischemia
You always want to check for ischemia when somebody fractures a
bone. For example, if somebody fractures their arm, then you want to check for
perfusion to the fingers. This can be accomplished by checking for a
pulse, or by checking for
capillary refill. You can check for capillary refill time by pressing the end of your finger gently into a healthy part of the patients skin (if the patient has a broken arm, press on a part of the arm that won’t disturb the fracture). In healthy individuals, the blood returns and the white skin at the site where you poked your finger turns pink within 2-4 seconds. If it takes significantly longer than this, than you know that peripheral
circulation if impaired.
For some variations of ischemia,
laboratory tests are extremely important in its
diagnosis.
Blood tests may show an elevated white
blood cell count. Sometimes
dye is injected into the patient, which helps show any narrow or blocked areas on an
x-ray. A
computed tomography (CT) scan may also show abnormalities in the area.
Treatment
If suffering from mild ischemia (no broken bones, etc.), gently
message the numb tissue until feeling is restored and the patient feels normal again. If it's the toes or fingers that need to be treated, gently message as well as move them back and forth to help blood flow back into the numb or tingly area. Not much can be done if the patient has a
fracture that is cutting off
circulation. You do not want to attempt to set the fracture yourself because the sharp ends of the bone can lead to further tissue damage if moved.
Evacuate the patient as soon as possible.
More severe cases of ischemia may be treated with
surgery. The narrow or blocked portion of the
arteries may be removed and the arteries are then reconnected to the aorta. Or, the blocked part of the artery may be bypassed, with a piece of vein or a plastic tube.
With surgery and
lifestyle changes, patients with severe ischemia can sometimes have a full
recovery. Lifestyle changes include not
smoking, following a
healthy diet,
exercising, and keep
cholesterol and
blood pressure under control.