Tag Archives: transfusion

Giving Rhogam (Rh Immunoglobulin) To A Man?

Rhogam is for women, right? The ATLS course points out that pregnant women who are Rh- and sustain significant blunt torso trauma should empirically receive Rhogam in case the fetus turns out to be Rh+.

But there is one situation where men might receive it. Most trauma centers use O- blood as their universal donor units because it does not contain any major antigens. However, O- blood is uncommon. Worldwide, only 4-9% of the population have this blood type. In China, the incidence of O- blood is nearly zero! So busy centers that don’t have much O- may substitute O+ blood for men. They then switch to the proper blood type when the crossmatch is complete

This makes sense, since men don’t ever have to worry about a Rh+ fetus. However, since this typically occurs at very busy (read: high penetrating injury) centers, there is a significant number of repeat offenders. And if they receive it again, the antibodies to the Rh factor they developed the first time can cause a significant hemolytic reaction. So men who receive O+ blood must be typed and given Rhogam if they are Rh-.

Reference: Emergency uncrossmatched transfusion effect on blood type alloantibodies. J Trauma 72(1):48-53, 2012.

Blood Transfusion With Component Therapy

About 40 years ago, blood banks started moving away from keeping whole blood and began separating it into components (packed cells, platelets, plasma, etc.) for more targeted use. For most uses, this is just fine. But what about trauma?

Trauma patients bleed whole blood. Doesn’t it make sense to give whole blood back? Much of our experience with massive transfusion is derived from our colleagues in the military. Two decades ago, the norm was to give 4 units of packed red cells or so, then give two units of plasma, and every once in a while slip in a bag of platelets. Our military experience seems to indicate that this 4:2:1 ratio is not optimal, and that something like 1:1:1 is better.

If you think about it, whole blood is already 1:1:1. Splitting it into components and then giving them back seems to be a lot of extra work (and expense) to accomplish the same thing as just giving a unit of whole blood. Plus it triples the exposure to infectious agents and antigens, since the components will usually come from three separate donors. Note that the data in the table above is true for fresh whole blood (not practical in civilian life); banked whole blood will lose some coagulation activity.

Is it time to think about supplying whole blood to trauma centers? And actually looking at whether the outcomes are better or not?

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.