ANEMIA

Any chronic illness can cause anemia, which is typically normocytic (normal MCV in the range 76-96). A hemoglobin (Hb) level below 8g/dL [5.0mmol/L] suggests another cause (usually bleeding or bone marrow involvement) in addition to that of chronic disease. In one study of 110 patients with advanced cancer who were admitted to St. Christopher’s Hospice, only 6 had a hemoglobin level below 8g/dL [5.0mmol/L].

The chronic anemia of advanced disease is usually asymptomatic because the patient is not active (and because there is a compensatory shift in the oxygen dissociation curve, so that the Hb molecule gives up its oxygen more easily in peripheral tissues). Symptoms of anemia only tend to occur with severe anemia (Hb less than 7g/dL) [4.3mmol/L] or if blood loss is sudden.

A common question is this: are the symptoms due to advanced disease and debility, or due to anemia?

Anemia can cause the following symptoms:

•  Dizziness

•  Fainting

•  Palpitations

•  Angina

•  Dyspnea

•  Heart failure

•  Fatigue

If anemia is causing distressing symptoms, in a patient with a reasonable prognosis (e.g., expected to live at least two weeks), blood transfusion may be indicated.

With some symptoms (dizziness, exertional dyspnea) it can be very difficult to know whether these are due to the anemia or to the advanced malignancy. If the patient has a prognosis of weeks (rather than days) it is justifiable to transfuse and to monitor symptoms. If symptoms improve significantly it has been worthwhile: If symptoms are unchanged the situation is clarified and further transfusions are not indicated.

Blood transfusions do not significantly improve the weakness and fatigue of advanced malignancy.

A transfusion can be used to give a patient a boost for a special occasion (to attend a wedding, for example) but any beneficial effects may be very short-lived (1 or 2 days).

One unit of blood raises the Hb level by about 1g/dL [0.6mmol/L]. Normally 4 units of packed cells are given over 16 hours, with a dose of oral furosemide 40mg in the early stage of transfusion to prevent the increase in circulating volume precipitating heart failure.

A retrospective study at St. Christopher’s Hospice over four years (1980-1983) showed that only 23 patients had blood transfusions (out of about 2,500 cancer patients admitted), only 13 showed improvement, 7 had mild reactions (fever, heart failure, raised urea levels with transient confusion) and 1 had a severe transfusion reaction. Blood transfusion carries risks, and an iatrogenic disaster is the last thing needed when coping with a terminal illness.

If the patient has been receiving multiple transfusions with little benefit, he may welcome a frank discussion and the opportunity to stop. Stopping regular transfusions does not inevitably hasten death – the patient can sometimes adjust to a low Hb level and live for weeks or even months.

Active bleeding that cannot be controlled is not usually an indication for transfusion, which simply causes heavier bleeding.

If the patient is iron deficient, as shown by a hypochromic hypocytic anemia (low MCH and MCV), it can be worthwhile giving iron if the patient has a reasonably good prognosis. Ferrous sulfate tablets should be taken with food to avoid gastritis. In far advanced disease the disadvantage of constipation due to the iron can outweigh any benefits.

The author and publisher have taken precautions to ensure that the information in this book is error-free. However, readers must be guided by their own personal and professional standards of good practice in evaluating and applying recommendations made herein. The contents of this book represent the views and experience of the author, and not necessarily those of the publisher.