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Write a short note on Acute Haemolytic Transfusion Reaction.

General Surgery · Final Professional

Definition & Cause

An acute haemolytic transfusion reaction is the rapid destruction of transfused red cells by the recipient’s antibodies, almost always due to ABO incompatibility — usually from a clerical/identification error giving the wrong blood. It is the most dangerous transfusion reaction and can be fatal.

Features & Management

It presents — often within minutes — with fever, chills, loin/back or chest pain, hypotension, tachycardia, haemoglobinuria (dark urine), and can progress to disseminated intravascular coagulation and acute kidney injury. Management: stop the transfusion immediately, maintain airway, breathing and circulation with oxygen and IV fluids, check the patient/unit identity, treat hypotension and support renal function (maintain urine output), manage DIC, and return the unit and samples to the laboratory.

DANGER / REMEMBER

At the first sign of an acute haemolytic reaction, stop the transfusion at once and resuscitate — delay is dangerous. Prevention is a correct bedside identity check, since almost all cases result from giving the wrong unit to the wrong patient.

CLINICAL PEARL

Acute haemolytic reaction = ABO-incompatible (wrong) blood: fever, loin pain, hypotension, haemoglobinuria, DIC. Stop the transfusion, resuscitate, protect the kidneys — and prevent it with a rigorous bedside check.

Prevention Above ALL

Because the acute haemolytic reaction is almost always the result of a preventable identification error, the emphasis in transfusion safety is overwhelmingly on getting the checks right rather than on treating the reaction after it has occurred. This means correct labelling of the cross-match sample at the bedside, accurate laboratory work, and a final bedside verification of the patient’s identity against the unit immediately before transfusion, performed for every single unit; the reaction that these checks prevent is so rapid and dangerous — potentially causing shock, renal failure and disseminated intravascular coagulation within minutes — that this discipline is regarded as one of the most important safety routines in clinical medicine.

Stop transfusion immediately and maintain urine output.

Feature	Detail
Cause	ABO incompatibility — usually clerical error
Onset	Within minutes of starting
Awake patient	Fever, loin pain, chest pain, anxiety
Anaesthetised patient	Hypotension, oozing, haemoglobinuria
Management	Stop transfusion, fluids, maintain urine output, inform blood bank

KEY POINT

Key points TO remember

Acute haemolytic reaction: recipient antibodies destroy transfused cells — usually ABO incompatibility (wrong blood).
Fever, loin/chest pain, hypotension, haemoglobinuria → DIC, acute kidney injury.
Stop transfusion immediately; ABC, oxygen, fluids; recheck identity; support renal function; manage DIC.
Prevent with a correct bedside identity check.

EXAM TIP

Sources: Morgan & Mikhail’s Clinical Anesthesiology; Miller’s Anesthesia; Ajay Yadav’s Short Textbook of Anaesthesia.

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