Tag Archives: Massive transfusion

Using Your ABCs To Predict Massive Transfusion

It’s nice to have blood available early when major trauma patients need it. Unfortunately, it’s not very practical to have several units of O neg pulled for every trauma activation, let alone activate a full-blown massive transfusion protocol (MTP). Is there any way to predict which trauma patient might be in need of enough blood to trigger your MTP?

The Mayo Clinic presented a paper at the EAST Annual Meeting today that looked at several prediction systems and how they fared in predicting the need for massive transfusion. Two of the three systems (TASH – Trauma Associated Severe Hemorrhage, McLaughlin score) are too complicated for practical use. The Assessment of Blood Consumption tool is simple, and it turns out to be quite predictive. 

Here’s how it works. Assess 1 point for each of the following:

  • Heart rate > 120
  • Systolic blood pressure < 90
  • FAST positive
  • Penetrating mechanism

A score >=2 is predictive of massive transfusion. In this small series, the sensitivity of ABC was 89% and the specificity was 85%. The overtriage rate was only 13%.

The investigators were satisfied enough with this tool that it is now being used to activate the massive transfusion protocol at the Mayo Clinic.

Bottom line: ABC is a simple, easy to use and accurate system for activating your massive transfusion protocol, with a low under- and over-triage rate.

Reference: Comparison of massive blood transfusion predictive models: ABC, easy as 1,2,3. Presented at the EAST 24th Annual Scientific Assembly, January 26, 2011, Session I Paper 4. Click here to view the abstract.

How to Predict the Need for Massive Transfusion in the ED

Massive transfusion is needed in about 3-5% of trauma patients. All Level I and II trauma centers are required to have a massive transfusion protocol.However, the protocol must be triggered in a timely manner to best benefit the major trauma patient.

Trauma surgeons at Vanderbilt validated a simple scoring system that allows accurate prediction of the need for massive transfusion in patients as they arrived in the ED. The system was called the ABC score (Assessment of Blood Consumption). It consists of the following 4 yes/no parameters:

  • Penetrating mechanism (0=no, 1=yes)
  • ED SBP <= 90 (0=no, 1=yes)
  • ED heart rate >= 120 (0=no, 1=yes)
  • Positive FAST (0=no, 1=yes)

The results of ABC when applied to trauma patients in the ED was as follows:

ABC Score         % requiring massive transfusion
0                                1%
1                               10%
2                               41%
3                               48%
4                             100%

This scoring system is simple, easy to use and easy to remember. No laboratory tests are needed, and the information needed can be gathered quickly.

Bottom Line: This is a simple and accurate prediction system for determining the need for massive transfusion in trauma patients. Recommended!

Reference: Cotton et al. J Trauma 66(2) 346-352, 2009.

Using Shock Index to Identify Risk for Massive Transfusion

This paper was presented at the 23rd Annual Scientific Assembly of the Eastern Association for the Surgery of Trauma.

Frequently, the need for massive transfusion in major trauma patients is apparent as soon as they arrive in the emergency department. Occasionally, the trauma team is surprised when an apparently stable patient catastrophically drops their pressure. This paper attempts to identify an easily calculated parameter to help predict those surprises before they happen.

The shock index (SI) is defined as the heart rate divided by the systolic blood pressure (HR/SBP). Normal values range from 0.5 to 0.7. The authors looked at all blunt trauma victims at their trauma center over a 9 year period who entered the ED with a SBP > 90. There were 8111 of these patients who met these criteria, and 276 required massive transfusion (3.4%), which they defined as 10 or more units of packed cells in 24 hours.

Analysis of their data showed that the risk for massive transfusion doubled with a SI > 0.9, quintupled for SI > 1.1, and was 7 times higher for SI > 1.3. There was some criticism for using only blunt trauma patients and for the authors’ definition of massive transfusion, but their data appeared to be sound.

The bottom line: the easily calculated Shock Index (HR/SBP) reliably predicts the need for massive transfusion in blunt trauma patients. It is probably valid for penetrating injury as well, but this was not addressed in the current paper.

Reference: Identifying Risk for Massive Transfusion in the Relatively Normotensive Patient: Utility of the Prehospital Shock Index. Vandromme, Griffin, Kerby, McGwin, Rue, Weinberg. University of Alabama at Birmingham.