Category Archives: Laboratory

MTP Week Part 4: How To Build Your Massive Transfusion Protocol

Massive Transfusion Protocol (MTP) week continues! I’m releasing the next Trauma MedEd newsletter to subscribers at the end of the week, which deals with advanced MTP topics. So leading up to that, I am reviewing the basics for the next several days. I’ll continue today with MTP activation triggers.

What criteria should trigger your massive transfusion protocol? Sometimes, it’s obvious. The EMS report indicates that your incoming patient is in shock. Or there was notable blood loss at the scene. Or they have a mangled extremity and will need blood products in the OR, if not sooner.

But sometimes the need for ongoing and large quantities of blood sneaks up on you. The patient is doing well but has an unexplained pressure dip. And it happens again. You give one of your  uncrossmatched units of blood. It happens again. At some point, you come to the realization that you’ve given six units of blood and no plasma or other products! Ouch!

Many trauma centers have adopted MTP criteria like:

  • More than 4 units given over 4 hours
  • More that 10 units to be given over 24 hours
  • Loss of half a blood volume over 24 hours

I call these the “psychic power” criteria, because one must surely be prescient to know this information just shortly after the patient arrives. Don’t include criteria like these at your center!

Instead use some sort of objective criteria. A simple one is the use of any of your blood refrigerator products or emergency release blood, or a calculated score such as the ABC score or shock index (SI).

ABC score is the Assessment of Blood Consumption score and gives one point each for a heart rate > 120, SBP < 90, positive FAST, penetrating mechanism.  ACS score > 2 was predictive of requiring MTP with sensitivity and specificity of about 85%. Overtriage was about 15%.

Shock index (SI) is defined as the heart rate divided by the SBP. Normal values are in the range of 0.5 to 0.7. Need for MTP was found to increase to 2x for SI of 0.9, 4x with an SI of 1.1, and 7x with SI 1.3.

A recent paper compared these two systems retrospectively on 645 trauma activations over a 5-year period. They found that they both worked well with the following results:

  • Shock index > 1 – 68% sensitive 81% specific
  • ABC > 2 – 47% sensitive, 90% specific

The study suggests that shock index is more sensitive, and takes less technical skill to calculate. Bottom line: just pick the some objective criterion you are most comfortable with and use it!

Reference: Accuracy of shock index versus ABC score to predict need for massive transfusion in trauma patients. Injury 49(1): 15-19, 2018

Well folks, that’s it for MTP week! Hope you enjoyed it.

And don’t forget to subscribe to TraumaMed if you want to get a full newsletter discussing advanced MTP topics tomorrow. Otherwise, you’ll be reading a post on CT scans and rib fractures in the elderly! Subscribe and download back issues by clicking here.

Links: (note – future links will not be live until 9am the day they are published)

Print Friendly, PDF & Email

MTP Week Part 3: How To Build Your Massive Transfusion Protocol

Massive Transfusion Protocol (MTP) week continues! I’m releasing the next Trauma MedEd newsletter to subscribers at the end of the week, which deals with advanced MTP topics. So leading up to that, I am reviewing the basics for the next several days. I’ll continue today with information on deactivating and analyzing your MTP.

Deactivation. There are two components to this: recognizing that high volume blood products are no longer needed, and communicating this with the blood bank. As bleeding comes under surgical control, and CBC and clotting parameters (and maybe TEG/ROTEM) normalize, the pace of transfusion slows, and ultimately stops. Until this happens, the MTP must stay active. Even a low level of product need should be met with coolers stocked with the appropriate ratios of products.

There are two ways to stop the MTP: the surgeon or their surrogate calls the blood bank (when no more blood products are to be used), or the blood bank calls the surgeon after the next cooler has been waiting for pickup for a finite period of time. This is typically about 30 minutes. It is extremely helpful if the exact deactivation time is recorded in the electronic medical record. However, this information can be obtained from the blood bank.

Analysis. It’s all over, and now the real fun begins. For most trauma centers, the blood bank maintains extensive data about every aspect of each MTP event. They record what units were released and when, when they were returned, which ones were used, were they at a safe temperature on return or were they wasted, and much, much more! Typically, one of the blood bank supervisors or a pathologist then compiles and reviews this data. What happens next varies by hospital.

Ideally, the information from every MTP activation gets passed on to the trauma program. Presentation at your transfusion committee is fine, but this data is most suitable for presentation at the trauma operations committee. And if significant variances are present (e.g. product ratios are way off) then it should also be discussed at your multidisciplinary trauma PI committee as well.

There are relatively few standard tools out there that allow the display of MTP data in an easily digestible form. Here are some of the key points that must be reviewed by the trauma PI program:

  • Demographics
  • Components used (for ratio analysis)
  • Lab values (INR, TEG, Hgb, etc)
  • Logistics
  • Waste

I am aware of two tools, the Broxton form and an MTP audit tool from the Australian National Blood Authority. The Broxton tool covers all the basics and includes some additional data points that cover activation criteria, TXA administration, and administration of uncrossmatched blood. Click here to check it out. The Australian tool is much more robust with more data points that make a lot of sense. You can download a copy by clicking here.

Tomorrow, I’ll continue with activation criteria for the MTP.

And don’t forget to subscribe to TraumaMed if you want to get a full newsletter discussing advanced MTP topics this Friday. Otherwise, you’ll be reading a post on CT scans and rib fractures in the elderly! Subscribe and download back issues by clicking here.

Links: (note – future links will not be live until 9am the day they are published)

Print Friendly, PDF & Email

MTP Week Part 2: How To Build Your Massive Transfusion Protocol

Massive Transfusion Protocol (MTP) week continues! I’m releasing the next Trauma MedEd newsletter to subscribers at the end of the week, which deals with advanced MTP topics. So leading up to that, I am reviewing the basics for the next several days. I’ll continue today with some tips on the logistics of your MTP.

MTP logistics include details such as who will be delivering the blood, what actually goes in each cooler, what ratios should be used, limitations imposed by the use of frozen plasma, and documentation. I’ll discuss details about ratios and FFP in the next Trauma MedEd newsletter.

The runners who travel between blood bank and the patient need to be selected carefully. Blood bank tech? Not ideal because they’ve got more important work to do. ED or OR tech? Maybe, as long as you’ve got a reliable pool. Student or resident? Probably not, because they may not know their way to the blood bank, which are typically placed in the farthest corner of the basement as possible. One of the most creative solutions I’ve seen is the use of a hospital security officer. Think about it. They know the hospital layout cold, including that obscure corner where the blood bank is located. And there are plenty around all the time!

Documentation is critically important, both in the trauma bay and the blood bank. Trauma activations, especially ones requiring MTP, are very fast moving and complex. Two sets of documentation are crucial: accurate records of blood product administration (on the trauma flow sheet), and documentation of just about everything else (in the blood bank). A specific timestamp on the trauma flow sheet that records the exact time of activation of MTP is a big plus.

What about coolers? I’ve seen everything used from uninsulated plastic buckets, picnic coolers, and pneumatic tube containers to large, self-contained rolling refrigeration units. The choice of container really boils down to cost vs waste. The cheaper it is, the less insulated it is, the more likely that blood products will be discarded due to high temperature if not transfused promptly. The best blend of cost vs utility seems to be the good, old-fashioned picnic cooler. It’s very portable, reasonably cheap, and can be tested for temperature maintenance. Just be sure to secure a pouch to the outside to keep platelets at room temperature to maintain full functionality.

Here’s a sample MTP cooler that’s ready for use. The platelets are in the pouch on the left. Note the reminder to prompt the team to give TXA if not contraindicated. This is often forgotten in the heat of the trauma activation.

Who actually runs your MTP? In some ways, it should run itself. Coolers get delivered, products get transfused. However, some decision making is needed to decide how long to continue and whether any tweaking of product ratios needs to happen. In the emergency department, the surgeon or emergency physician can do this. But once a trauma patient arrives in the OR, that is no longer the case. The emergency physician was left behind in the ED and the surgeon is up to her elbows in trouble. What about the anesthesiologist? Nope, they are busy keeping the patient safely asleep, regulating rapid infusions, and actually administering the blood.

Most of the time, however, these two physicians actually end up running the MTP while multi-tasking at their other job. Unfortunately, this can lead to errors and delays. One best practice to consider: a highly trained trauma resuscitation nurse or advanced practice provider (APP) can run the MTP from the sidelines. They travel with the patient from ED to OR, managing the MTP the entire time. This offloads responsibility from busier people.

Tomorrow, I’ll continue with MTP deactivation and analysis.

And don’t forget to subscribe to TraumaMed if you want to get a full newsletter discussing advanced MTP topics this Friday. Otherwise, you’ll be reading a post on CT scans and rib fractures in the elderly! Subscribe and download back issues by clicking here.

Links: (note – future links will not be live until 9am the day they are published)

Print Friendly, PDF & Email

MTP Week Part I: How To Build Your Massive Transfusion Protocol

It’s Massive Transfusion Protocol (MTP) week! I’m releasing the next Trauma MedEd newsletter to subscribers at the end of the week, which deals with advanced MTP topics. So leading up to that, I’ll be reviewing the basics for the next several days. I’ll start today with tips on how to build a solid MTP at your center.

Your massive transfusion protocol is a complex set of processes that touch many, many areas within your hospital. There are five basic components (and a few sub-components) to any MTP, so let’s dig into them one by one. They are:

  • Universality
  • Activation
  • Logistics
    • Components
    • Runners
    • Documentation
    • Coolers
  • Deactivation
  • Analysis

Let’s scrutinize each one, starting with the first two today.

Universality. This means that there should be one, and only one MTP in your hospital. I’ve seen some hospitals that have one MTP for trauma, one for cardiothoracic surgery, one for OB, one for GI, and on and on. Yes, each of those services deals with patients who are suffering from blood loss. But it’s the same blood that your trauma patients lose! There’s no need to create a protocol for each, with different ratios, extra drugs, etc. This can and will create confusion in the blood bank which may lead to serious errors.

Activation. This consists of two parts: how do we decide to activate, and then how does everyone involved find out that the MTP is actually being activated? I’ll discuss activation criteria on Thursday. But what about the notification process? Phone call? Order in the electronic medical record (EMR)? Smoke signals?

The most reliable method is a good, old-fashioned phone call. Do not use your EMR except for documentation purposes. Unless there is a very reliable system in the blood bank that translates an EMR order into an annoying alarm or flashing lights, don’t rely on this at all.

Then decide upon the minimum amount of information that the blood bank needs to begin preparing blood products. This usually consists of a name or temporary patient identifier, sex, and location of activation. Ensure that an ID or transfusion band is affixed to the patient so that wrong blood products are not given in multiple patient events.

Tomorrow, I’ll continue with the logistics of the MTP.

And don’t forget to subscribe to TraumaMed if you want to get a full newsletter discussing advanced MTP topics this Friday. Otherwise, you’ll be reading a post on CT scans and rib fractures in the elderly! Subscribe and download back issues by clicking here.

Links: (note – future links will not be live until 9am the day they are published)

Print Friendly, PDF & Email

How Much Plasma Does It Take To Reverse Warfarin?

For decades, plasma (with vitamin K) was the mainstay for reversing warfarin. Over the past several years, prothrombin complex concentrates (PCC) have made inroads in the management of this problem because of its sheer speed of action.

There are two problems with plasma. First, most hospitals still have only fresh frozen plasma (FFP), and it takes 20-30 minutes to thaw. This adds some up-front time to administration. Then, it takes time to infuse the 250cc or so of volume in each unit. This may be 1 or 2 hours, depending on policy and patient tolerance of a bolus of colloid.

If it always just took one unit of plasma to correct the INR to a desirable range (typically 1.5-1.6), then the whole PCC conversation might be moot. You could potentially have the INR corrected in 30-60 minutes depending on your patient’s cardiovascular system.

But how many does it really take? A group at Eastern Virginia Medical School in Norfolk, VA looked at this problem and tried to come up with a mathematical formula. They examined a year of warfarin reversal data at their hospital. Patients with severe clotting disturbances (advanced cirrhosis, DIC) and those who received additional products (PCC or activated Factor VII) were excluded.

Using data from nearly 1,000 patients, the following formula was derived and validated:

∆ INR = (0.57 ∙ preINR) – 0.72

So a patient with an INR of 3.0 would be expected to show a decrease of 0.99 to about 2.0 after one unit. This formula can be used iteratively to figure out how many units will drop the INR to the goal range.

I don’t know about you, but I hate doing math in the middle of a trauma resuscitation. I need something quick and dirty. A physician from NYU Langone in NYC commented on the article, and derived a nice little table to simplify the process. He calculated the number of plasma units based on some common INR ranges, assuming that the goal was to get it down under 1.5. Here is the table:

Bottom line: This is a nice little piece of information to tuck into your pocket or phone. For patients inside the usual therapeutic values, it will take 2-3 units of plasma to reverse. For your average older human with average comorbidities, expect this to take 4-6 hours, not counting ordering, thawing, and delivery. If my definitions of “life-threatening bleeding” are met (see below), your patient may have significant adverse events during this time frame. So think very seriously about using PCC instead.

Related posts:

Reference: Fresh Frozen Plasma Dosing for Warfarin Reversal: A Practical Formula. Mayo Clin Proc 88(3):244-250, 2013.

Print Friendly, PDF & Email