The medication aprotinin is used to control blood loss in patients undergoing major heart or coronary bypass surgery. It was taken off the market in much of the world in 2007 because of the risk of death due to anaphylactic shock, though it remains available in some countries on a limited basis.
Made from a naturally occurring chain of amino acids that is collected from the lung tissue of cows, aprotinin works by blocking the effects of the hormone cytokine, which encourages certain areas to inflame, increasing the amount of blood in these regions. After the amino acids are removed from bovine lung tissue, they are suspended in an isotonic solution and administered to a patient through a vein.
Aprotinin is used to prevent blood loss at the time of surgery. It controls blood loss in both coronary artery bypass and cardiopulmonary bypass surgeries. Both of these procedures can create a great deal of blood loss because they involve the large blood vessels near the heart.
Patients are usually given a test dose of aprotinin before they receive a full dose. Doctors use this test to determine a patient’s risk of anaphylactic shock. Despite these tests, there are some patients who have died from an anaphylactic response even when they showed no adverse reaction to the test dose. It is also possible to have a deadly reaction to the test dose itself.
There are many possible side effects from aprotinin, though the medication is usually received well by most patients. Organ failure, renal dysfunction, immune disorder, cardiac arrest, hemorrhage and death are all possible side effects, so a health care professional will carefully evaluate a patient’s potential benefit from the medication before administering it. Patients who have received multiple doses of the medication seem to be at the greatest risk for developing life threatening reactions to it.
The United States, Australia and Canada make aprotinin available only in special circumstances. Patients who are deemed to be at great risk of blood loss may be given the medication if their doctor determines that the potential benefits offset the dangers of treatment. There are very few patients, however, who are given this drug because of the significant risk of death. It was re-released in 2009 after it's removal from the market in 2007 to undergo further testing. Many European nations no longer allow treatment with aprotinin.