Postoperative anemia

definition

Postoperative anemia is a manifestation of anemia that becomes apparent shortly after an operation.

In general, one speaks of anemia if the hemoglobin value in men falls below 14g / dl.
In women, the hemoglobin value should not fall below 12g / dl.

Another parameter for diagnosing anemia is the hematocrit value, which indicates the proportion of red blood cells in the total volume of blood. It should be 40-54% for men and 37-47% for women.

causes

Surgical intervention can aggravate a previously existing, symptom-free anemia, as bleeding occurs during an operation and frequent diagnostic blood tests may be necessary in preparation for an operation.

An operation puts a strain on the human body, the stress that is triggered can lead to blood formation disorders and also trigger postoperative anemia in patients without pre-operative anemia.

The injuries caused by the operation cause the release of messenger substances that mediate inflammation and thus lead to an inflammation-like reaction.
The messenger substances released are also known as acute phase proteins and include, for example, the inflammation parameter CRP, which is also well known in the general population.C-reactive protein).
These inflammatory messengers slow down the production of the precursor cells of the red blood cells (Erythrocytes) by inhibiting the production of erythropoietin.

Erythropoietin is a hormone that is mainly produced in the kidney and that promotes blood formation.

In addition, the inflammatory messengers reduce iron absorption through the intestine. The production of the oxygen-transporting molecule on the red blood cells, the hemoglobin, requires iron.
A reduced iron absorption can lead to an iron deficiency and thus to anemia, either due to empty iron stores before the operation or due to a longer absorption disorder in the intestine.

Read more on this topic at: Iron deficiency anemia

The more extensive a surgical procedure, the more inflammatory messengers are released. As a result, major surgery usually causes more postoperative anemia than minor surgery.

Symptoms and complications

Symptoms of postoperative anemia are similar to symptoms of one anemiathat was not diagnosed during surgery.

Weakness, tiredness, shortness of breath, difficulty sleeping and heart attack-like pain (Angina pectoris) belong to.

After surgery, patients with anemia have a harder time recovering and getting back on their feet in a reasonable time.

The greater the degree of anemia, the longer the body needs to regenerate.
Severe postoperative anemia is associated with a higher rate Disease and death rate associated.

The temporary, mild postoperative anemia with no effect on the flow properties of the blood and the circulation does not increase the disease and death rate.

Please also read our article on this Consequences of iron deficiency.

diagnosis

The diagnosis of anemia can be made after a blood sample and subsequent examination of the Blood count be asked.

The doctor pays particular attention to the Hemoglobin value (so.), the Hematocrit value (so.) and the total number of red blood cells.

Through a physical exam, the doctor can identify typical symptoms of anemia such as paleness of the mucous membranes or the Crease determine.

therapy

If severe acute bleeding occurs intraoperatively, the patient must come along Blood transfusions treated to ensure oxygen supply to all organs.

The administration of foreign blood during an operation does not affect the occurrence of postoperative anemia.

If anemia occurs after an operation, blood formation can be stimulated by supportive therapies.
The gift of iron and Erythropoietin is possible.

The theoretical total iron requirement can be calculated using a simple formula:

Iron requirement = 150 × (hemoglobin target value-hemoglobin baseline value)

Iron can be administered in the form of tablets, intramuscular injections or intravenous infusions.
The tablet administration is a cheap and simple procedure, but the iron given in this way cannot be optimally absorbed through the intestine and there are side effects such as heartburn, Vomit, diarrhea, constipation and stomach pain cause.

Iron tablets are best taken before meals, as otherwise iron absorption is reduced.
Black tea, coffee and milk almost completely prevent iron absorption in the intestine.
The intravenous administration of iron saccharate as a short infusion has hardly any side effects.

Erythropoietin is a hormone that the Stimulates blood production and is available in recombinant form.
It is used as a supplement if anemia does not respond or only inadequately to the administration of iron supplements. The iron supplements must continue to be taken even during therapy with erythropoietin, otherwise a result of the increased blood production Iron deficiency can occur.

Erythropoietin can also pre- and post-operative can be given to increase the hemoglobin value, but therapy with erythropoietin must be adjusted individually due to the high costs.

Iron substitution

Iron substitution can be useful in many cases to treat postoperative anemia. In general, iron deficiency is the most common cause of anemia, but there are also a number of other causes. After an operation there is usually an increase in inflammatory messengers as a reaction of the body to the procedure. One of the many effects of these messenger substances is that the absorption of iron from food via the intestines is reduced. Especially in patients who already have borderline iron reserves before an operation, this can result in postoperative anemia to be triggered. In addition, the body loses iron through blood loss during the operation. The doctor can determine whether iron deficiency is the cause of postoperative anemia by taking special blood tests for iron storage proteins. If the results indicate iron deficiency, temporary iron replacement is indicated. If there is another cause, however, this does not make sense and other measures may be necessary. In any case, your doctor should check your blood count and other relevant values.

Duration of postoperative anemia

How long postoperative anemia lasts cannot be answered in general, as it depends on many different factors. These include the type and severity of the intervention, the amount of blood loss and the general condition of the patient's body and its ability to produce new blood cells. Often the values ​​for the red blood pigment rise (hemoglobin) and red blood cells (Erythrocytes) returns to normal within a few days. If a blood transfusion is required due to high blood loss, the levels will increase directly with the transfusion. However, in some cases, postoperative anemia persists longer. In such a case, further diagnostic measures (e.g. iron or vitamin value determinations) and possibly therapy are necessary.

prophylaxis

Falls even before an operation If you have severe anemia, you should look for the cause in order to find the underlying disease that caused it.

In older patients in particular, anemia is often just a symptom of another disease.
If the underlying disease is then treated, the existing anemia improves and the risk of postoperative anemia decreases.

As patients with diseases of Heart and / or vessels Anemia is much more difficult to cope with than patients with healthy heart and blood vessels, if these diseases should be treated as best as possible before operations can be planned in order to keep complications from postoperative anemia to a minimum.

It is of course best if the anemia does not occur at all postoperatively.
Precise surgical work and fast intraoperative Hemostasis can prevent major blood loss but cannot completely rule out postoperative anemia.