Blood, Electrolytes, and Intravenous Infusions

3-19. ADVERSE BLOOD PRODUCT REACTIONS

Most adverse transfusion reactions are caused by leukocytes, platelets, and plasma proteins (since red blood cell antibodies have already been checked). All the care in cross-matching blood in the laboratory can be negated by administering the blood to the wrong patient. Always double-check.

a. Immediate Effects. An adverse effect can be either immediate or delayed. If the effect is immediate and the transfusion reaction involves more than just a reddening of the skin, the transfusion should be stopped immediately, but the intravenous line should be kept open.

(1) Congestive heart failure. Congestive heart failure that is caused by circulatory overload shows up as coughing, cyanosis, and difficulty in breathing. This is probably the most preventable adverse reaction to transfusion. If a patient is susceptible to circulatory overload, concentrated red blood cells should be transfused at no faster than one milliliter per kilogram of body weight per hour.

(2) Febrile reactions. Febrile reactions (fever), often preceded by chills, are the most common adverse transfusion reactions. These reactions are usually mild and result mainly in patient anxiety and discomfort. Rarely, there is some infiltration in the lungs, reduction in the body's white cells, shock, or death. There are variations in blood products or medications that may lessen febrile complications.

(3) Allergic reactions. Allergic reactions are usually relatively mild. Most are local skin redness, hives, and itching. These are treated with antihistamines. Flushing, nausea and vomiting, diarrhea, changes in blood pressure and anaphylaxis are severe reactions that sometimes require a specially prepared blood product. Some severe reactions can be treated by antihistamines. Others require epinephrine.

(4) Hemolytic reactions. These are often difficult to detect. Initial hemolytic reactions can be flushing, a feeling of apprehension, chest or back pain, chills, fever and nausea, or vomiting. During anesthesia, diffuse bleeding may be the only evidence. Severe reactions include excessive hemoglobin in the blood plasma, hemoglobin in the urine, abnormally low blood pressure, coagulation in the blood vessels, renal failure, and death.

(5) Bacterial contamination. This rarely occurs. When it does occur, a life-threatening reaction is likely. Signs and symptoms of bacterial contamination include the rapid onset of chills, high fever, vomiting, diarrhea, very low blood pressure, and acute renal tubular necrosis.

(6) Hypothermia. If blood is not warmed before a massive transfusion, hypothermia can cause ventricular arrhythmia and cardiac arrest.

(7) Hyperkalemia. Certain patients can react to the potassium that slowly leaks into the blood plasma during storage. The patient may exhibit neuromuscular problems such as muscular weakness and paralysis. Heartbeat may be irregular (usually slowed), and death could result from cardiac arrest.

(8) Microemboli. Transfusion of large volumes of banked blood may require filtering to remove debris accumulated from the breakdown of platelets, fibrin, and leukocytes during storage. This can lead to impaired oxygen transport ability in some patients who are administered large amounts of banked blood. The patient will exhibit breathing difficulties and pain in the extremities.

b. Delayed Effects. Adverse reactions can sometimes take weeks to show up. These are generally beyond the capability of the medical NCO to correct.

(1) Hemolytic. Delayed hemolytic reactions occur and usually result in extravascular removal of transfused cells from the circulation. This effect may take days or even weeks after the transfusion.

(2) Viral Hepatitis. The occasional occurrence of post-transfusion hepatitis remains a serious consequence of blood transfusion. Albumin, plasma protein fraction, and immunoglobulin preparations are regarded as safe derivatives since hepatitis virus is usually inactivated or removed during preparation.

(3) Others. Diseases such as malaria, acquired immune-deficiency syndrome (AIDS), hepatitis, and syphilis can be transmitted. Adequate donor screening is the only effective protection against these diseases presently.