One speaks of ischemia in the case of reduced blood flow or a complete failure of blood flow to a tissue area. Ischemia can occur anywhere in the body and can be life-threatening depending on the location, extent and duration.


What is ischemia?

According to, ischemia of a small area of ​​skin due to pressure damage may not become apparent for many hours. A blood flow failure in the brain, on the other hand, leads to unconsciousness in just 15-20 seconds and is acutely life-threatening, since irreparable necrosis occurs within 7-10 minutes.

The insufficient supply of blood to a tissue area is referred to as ischemia. This can be due to insufficient blood flow or a complete stoppage of blood flow.

If ischemia lasts only a short time, the tissue can usually recover quickly after reperfusion. In the case of prolonged ischemia, the disturbed metabolism leads to – possibly irreparable – tissue destruction.

How long an ischemia can be tolerated depends primarily on its location: Certain organ systems such as the central nervous system are particularly sensitive to a lack of oxygen, while other tissues such as the skin can tolerate ischemia for several hours.


The most common causes of ischemia are internal pathological changes in the cardiovascular system. Vascular narrowing (stenoses) caused by arteriosclerosis develop gradually and cause chronic ischaemia.

Sudden vascular occlusions due to thrombosis or embolism lead to acute ischaemia. The traumatic destruction of a blood vessel also causes a loss of blood flow. More rarely, ischemia is caused externally, e.g. B. by tying off a part of the body to stop bleeding, by tumors or by chronic pressure stress when confined to bed.

The consequences for the metabolism of the affected area are the same in both cases: Because of the insufficient oxygen supply, lactate builds up and the ischemic area becomes overly acidic (metabolic acidosis).

Due to the lack of energy, the cells can no longer maintain their particle and liquid balance: they swell and finally perish. When necrosis begins, one speaks not only of ischemia, but of the clinical picture of the infarction.

Symptoms, Ailments & Signs

Ischemia typically manifests itself as an acute clouding of consciousness. Those affected usually feel slightly dizzy or tired, and as the disease progresses, unconsciousness and coma can occur. A mild ischemic stroke causes nausea and vomiting.

In addition, visual disturbances and visual field defects can occur. Also characteristic of a cerebral infarction are pathological reflexes of the Babinski group and neurological deficits. If the cranial nerves are involved, swallowing difficulties and a foreign body sensation in the throat occur. Speech can be slurred and unclear.

Many patients suffer a blackout and no longer remember the incident. Partial or complete memory loss can also occur, depending on the severity of the ischemia. Hemiplegia often occurs as well. Many of those affected can no longer move their arms or legs, or only with great effort.

However, paralysis of all extremities occurs only rarely. In severe cases, the stroke leads to the death of the person affected within a few minutes. First, there is respiratory arrest, which leads to an insufficient supply of oxygen to the brain and ultimately to brain death. The symptoms of ischemia are usually not reversible. Most of those affected suffer from long-term effects.

Diagnosis & History

The course of ischemia depends fundamentally on which organ system is affected. Ischemia of a small area of ​​skin due to pressure damage may not become apparent for many hours.

A blood flow failure in the brain, on the other hand, leads to unconsciousness in just 15-20 seconds and is acutely life-threatening, since irreparable necrosis occurs within 7-10 minutes. The working heart muscle is also very sensitive to a lack of oxygen and can only tolerate ischemia for a few minutes. Pain and shock are typical of larger ischemias; however, the other clinical symptoms differ greatly depending on the localization.

Indications of severe extremity ischaemia are provided by the 6 P signs according to Pratt: pain (pain), pallor (pallor), lack of pulse (pulselessness), sensory disturbance (paresthesia), paralysis (paralysis), shock (prostration). A thorough medical history is important, since vascular occlusions are almost always preceded by previous illnesses.

The diagnosis of ischemia is supported by laboratory findings, functional diagnostics (e.g. EKG) and imaging methods (duplex sonography, catheter angiography, computer sonography or magnetic resonance imaging).


Ischemia can be life-threatening for a patient if it occurs over a long period of time. Poor blood circulation in the affected tissue can also lead to irreversible consequential damage to the entire body. The patients often suffer from shortness of breath or necrosis due to the lack of oxygen.

In the worst case, it can also lead to a heart attack and ultimately to the death of the patient. Sufferers may also experience a brain failure, resulting in loss of consciousness. If this persists for a longer period of time, consequential damage to the brain can also occur, so that the patients suffer from paralysis or spasticity.

There is also pain, sensory disturbances or severe paleness. Immediate treatment is required for ischemia in order to avoid irreversible sequelae and complications. Surgical interventions may also be necessary. As a rule, the life expectancy of the patient is significantly reduced and limited by the ischemia. However, the further course of the disease depends on the cause of this disease.

When should you go to the doctor?

If the affected person notices circulatory disorders, he should consult a doctor in good time. If you experience cold limbs, numbness on the skin, a sudden pale discoloration of the face or sensory disturbances, you need to see a doctor. In the event of pressure pain, a general feeling of pain or discomfort, further examinations should be carried out to clarify the cause. If there are cardiac arrhythmias, a racing heart, a change in blood pressure or clouding of consciousness, a doctor is needed.

If you lose consciousness, you must call an ambulance. In these cases, the person concerned suffers a life-threatening condition within a few minutes and requires immediate intensive care. If there are disturbances in brain activity, there are interruptions in attention or concentration and if the person concerned suffers from a feeling of pressure inside the head, he should consult a doctor.

If signs of paralysis appear on the body, no pulse can be felt and the person concerned suddenly feels ill, medical care must be sought. In the event of a drop in performance, dizziness, unsteady gait and a loss of the usual strength, a visit to the doctor is advisable. In the event of inner weakness, clouded perceptions, tiredness and exhaustion, a doctor should be consulted. If the symptoms increase in scope, a medical examination should take place as soon as possible, as an acute threat to life can arise.

Treatment & Therapy

The aim of every ischemia therapy is to ensure an adequate blood supply to the ischemic area again. Acute ischaemia with infarction requires rapid action:

If there are no contraindications, drug systemic or local lysis therapy is tried first. If this does not work or if the time window for lysis therapy has already expired, vascular surgical revascularization is possible: surgical removal of a thrombus, vascular dilatation or bypass operations. Sometimes these procedures can be performed via catheters, in other cases they require major surgery.

In the case of subacute forms of ischemia, dilating vascular prostheses (stents) are also used preventively. In patients with ischaemia, drug anticoagulation, ie a reduction in the tendency for blood to clot, is also useful in order to prevent (further) embolism and thrombosis. Heparin or vitamin K antagonists, for example, are given for this purpose. In addition, patients at risk of chronic ischemia often receive calcium antagonists, beta- blockers and/or nitro preparations.

Outlook & Forecast

The prognosis of ischemia is generally poor. Regardless of where it is located in the body, it severely impairs quality of life or, in severe cases, threatens life. The person concerned suffers from various complaints, which have an increasing character. If left untreated, the premature death of the affected person is to be expected, since there is a risk of a heart attack.

Depending on the location of the reduced blood circulation, medical care can lead to lifelong impairments or a life-threatening situation. For a favorable prognosis, an early and comprehensive medical examination is necessary. The longer treatment is delayed, the greater the likelihood of complications or permanent impairment. In addition to metabolic disorders, there is a risk of damage to the brain. Irreparable tissue damage occurs, which in severe cases leads to functional disorders in addition to organ disorders.

In the event of acute ischemia, immediate action is necessary to ensure the survival of the affected person. Lifelong impairments and a reduced quality of life are to be expected because of the after-effects. Overall performance is reduced and there may be limitations in movement or coordination. Everyday life has to be restructured, since the fulfillment of usual tasks can usually no longer be adequately guaranteed after the incident.


Ischemia can generally be prevented with measures that keep the cardiovascular system healthy: with exercise, good nutrition with a special focus on healthy fats and not smoking. Careful anticoagulation should be ensured in patients with pre-existing conditions such as cardiac arrhythmias that predispose to vascular occlusion, and in patients who are bedridden after surgery. In addition, extremities may only be tied off in an absolute emergency, because amputation of the affected body part may become necessary after prolonged ischemia.


After treatment by the doctor treating you, it is particularly important in the case of ischemia to ensure a healthy and balanced lifestyle. Avoiding alcohol and nicotine (in any form) is essential here. You should also keep an eye on your cholesterol levels. Cholesterol levels that are too high can lead to further complications in the vascular system. Disturbances in the lipid metabolism must be avoided at all costs.

Body weight should also be taken into account; Being overweight can lead to other problems that the patient should definitely avoid. Sport and sufficient exercise such as walking, jogging, team sports or cycling are supportive and in any case health-promoting. Continuous monitoring for high blood pressure and diabetes is also recommended.

A balanced diet with plenty of fiber is also beneficial in follow-up care for ischemia. Dietary fibers not only lower cholesterol levels, but also ensure healthy bowel movements. Vitamins help prevent further vascular diseases. Vitamins E and C are particularly important here. Carotenoids can also have a positive effect.

The patient should avoid eating high-fat or fried foods. Hydrogenated fats should be removed from the diet. The “stress” factor also plays an important role in the aftercare of ischemia. In the professional and private environment, this should be minimized as much as possible.

You can do that yourself

Individuals affected by ischemia should seek medical attention. In order to be able to determine suitable self-help measures, the causative disease must first be determined. That is why immediate medical evaluation is the most important measure that an affected person can take.

Mild ischemia can be cured relatively quickly with medication and rest. Even after an operation, bed rest and rest apply to those affected. If the pain persists, it is best to inform the doctor. In consultation with the doctor, natural remedies such as St. John’s wort or belladonna can be used to reduce the symptoms. Massages, acupuncture and other alternative treatment methods are also permitted with the consent of the doctor.

After the disease has been cured, the lifestyle must be changed. Above all, measures that strengthen the cardiovascular system are important, such as exercise, a healthy and balanced diet and avoiding stimulants such as alcohol and nicotine. Ischemia patients should also avoid stress and ensure a restful night’s sleep. At the same time, regular check-ups in the hospital are indicated because, depending on the underlying disease, ischemia can always occur.