ABC Score For Massive Transfusion

Determines the necessity of triggering massive transfusion (MT) protocol and likelihood of administration of pRBC.

In the text below the calculator there is more information on the factors that are taken into account by the ABC score and its interpretation.

The ABC score for massive transfusion is used to assess the likelihood of massive transfusion to be needed, where MT is defined as administration of 10 units pRBC or more, in the first 24 hours after admission.

It is based on routinely collected bedside data, such as systolic blood pressure or heart rate and can accurately predict the likelihood blood transfusion will be needed.

The presence of each of the 4 items in the ABC score is awarded 1 point, therefore the lowest score is 0 and the highest obtainable score is 4.

The higher the score, the bigger the likelihood for massive transfusion (more than 10 units pRBC) to be initiated.

ABC score Massive transfusion probability
0 Unlikely 1%
1 Unlikely 10%
2 Likely 41%
3 Likely 48%
4 Highly likely 100%


Penetrating mechanism of injury


Positive focused assessment sonography for trauma (FAST)


Arrival systolic blood pressure of 90 mmHg or less


Arrival heart rate of 120 bpm or above

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ABC score items

The score is based on four bedside, non-laboratory items, all weighted equally in the result. The trauma patient will be evaluated in respect of the following:

■ Penetrating mechanism of injury;

■ Positive focused assessment sonography for trauma (FAST examination);

■ Arrival systolic blood pressure of 90 mmHg or less;

■ Arrival heart rate of 120 bpm or above.

The penetrating mechanism of injury means that the trauma patient is more likely to require blood transfusion.

In blunt trauma, the FAST examination is used to screen for pericardial effusion or hemoperitoneum.

On the other hand, massive transfusions only occur in 3 to 5% of trauma cases. However, when they are required, they are most likely to be associated with high morbidity and mortality rates.

When there is blood depletion, hypotension occurs and the increased heart rate tries to compensate it.

One of the benefits brought by the ABC score is the rapidity by which decisions can be made, as complications are more likely to appear when there is delay in the initiation of blood transfusion protocols.

Complications can appear due to the clinicians waiting too long before initiating the protocols and although massive transfusions only occur in 3 to 5% of trauma cases, when this happens and the intervention is not rapid, morbidity and mortality rates increase significantly.


ABC score interpretation

The presence of each of the above four criteria weighs 1 point from the overall 4 points attainable. Therefore, the scores range from 0 to 4.

■ Scores below 2 are unlikely to require massive transfusion.

■ Scores of 2 and 3 are likely up to 48% to require MT whilst scores of 4 are almost certain to require transfusion.

ABC score Massive transfusion probability
0 Unlikely 1%
1 Unlikely 10%
2 Likely 41%
3 Likely 48%
4 Highly likely 100%

About the original study

The ABC score comes from the Assessment of Blood Consumption score which was created as a mean to predict likelihood of MT initiation.

The study was conducted on 596 patients and the ABC score was compared to the Trauma-Associated Severe Hemorrhage (TASH) score through the Area Under the Receiver Operating Characteristic Curve (AUROC) method.

The sensitivity and specificity ranges are 75% to 90%, respectively 67% to 88% at multiple trauma centres.


Massive transfusion guidelines

MT is defined as the transfusion of 10 units or more of pRBC in the first 24 hours after admission as a response to massive and uncontrollable hemorrhage.

MT is also considered when 5 units of pRBC are transfused over 3 hours.

Every health care institution has transfusion protocols and most commonly, these contain plasma, platelets and packed red blood cells.

MT protocols are known to increase chances of survival in the management of acute coagulopathy of trauma.

Transfusions are meant to restore the normal blood volume and reinstate homeostasis, oxygen carrying and normal oncotic pressure.


Original source

Nunez TC, Voskresensky IV, Dossett LA, Shinall R, Dutton WD, Cotton BA. Early prediction of massive transfusion in trauma: simple as ABC (assessment of blood consumption)? J Trauma. 2009; 66(2):346-52.


Cotton BA, Dossett LA, Haut ER, Shafi S, Nunez TC, Au BK, Zaydfudim V, Johnston M, Arbogast P, Young PP. Multicenter validation of a simplified score to predict massive transfusion in trauma. J Trauma. 2010; 69 Suppl 1:S33-9.

Specialty: Hematology

System: Cardiovascular

Objective: Assessment

Type: Score

No. Of Items: 4

Year Of Study: 2009

Abbreviation: ABC

Article By: Denise Nedea

Published On: March 15, 2017

Last Checked: March 15, 2017

Next Review: March 9, 2023