Time for some more philosophy! After providing trauma care for decades, one begins to see the common threads and underlying principles of their area of expertise. I’ve been trying to crystallize these for years, and today I’m going to share one of the most basic laws of trauma care.

The First Law of Trauma: Any anomaly in your trauma patient is due to trauma, no matter how unlikely it may seem.

Some examples:

  • An elderly patient who crashes his car and presents with arrhythmias and chest pain is not having a heart attack. Nor does he need a cardiologist or a trip to the cath lab.
  • A spot in the liver after blunt trauma is not a cyst or hemangioma; it is a laceration until proven otherwise.
  • A patient found at the bottom of a flight of stairs with blood in their head did not have a stroke and then fall down.

Bottom line: The possibility of trauma always comes first! It is your job to rule it out. Only consider non-traumatic problems as a last resort. Don’t let your non-trauma colleagues try to steer you down the wrong path, only to have your patient suffer.

What’s The Best Trigger For Your Massive Transfusion Protocol?

Every trauma center verified by the American College of Surgeons Committee on Trauma (ACS-COT) must have a massive transfusion protocol (MTP). The details and logistics of the protocol are up to the individual center. The difficult question is: how is a trauma professional to know that the MTP should be activated?

Sometimes it’s extremely obvious. The patient is very hypotensive. Blood is spurting all over the room. But sometimes it’s more subtle and the need just seems to creep up on you. And frequently, this delays activation and the actual arrival of the blood that is so desperately needed.

I’ve previously written about common triggers for the MTP, including psychic powers, shock index, and ABC index. See the links below to read my MTP week posts. But is one better than the other? The group at Vancouver General Hospital in British Columbia, Canada performed a systematic review of the literature to try to answer this question.

A total of 45 pertinent articles were identified in the literature up to 2017. Fifteen different scoring systems were evaluated involving combinations of clinical assessment, laboratory tests, and ultrasound evaluation.

Here are the factoids:

  • The best validated score using clinical assessment plus ultrasound was the Assessment of Blood Consumption score (click here for my post). This was the easiest to score compared to other systems using ultrasound.
  • Shock index (SI) was the only validated system using just the clinical exam
  • Some other studies were promising, with excellent areas under the receiver operating characteristic curve (AUROC), but had not been validated. The best of the bunch was one from Mina et al, but it is complicated enough to require a smartphone tool for calculation.
  • Other promising studies required laboratory evaluations which preclude their use at the time of patient arrival
  • Scoring systems that used more variables generally showed better correlation with actual need for MTP, but were more less likely to provide suficiently early predictions
  • Most validation studies involved single centers
  • No studies were designed to or able to show improved outcomes

Bottom line: There are many, many systems out there for predicting need for activation of the MTP (at least 15 to date)! This review concludes that the system used should be tailored to the center implementing it.

Simpler is better. I still recommend either Shock Index (SI) or ABC. Shock index is quickly calculated based on physical exam as heart rate divided by systolic blood pressure. The normal range is 0.5 to 0.7. The likelihood of MTP escalates 2x with SI > 0.9, 4x if SI > 1.1, and 7x with SI > 1.3. The ratio can easily be calculated based on numbers available from EMS providers prior to arrival. Basically, pick your threshold.

The Assessment of Blood Consumption (ABC) uses four parameters, three of which could be reported prior to patient arrival:

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

If two or more criteria are met, the patient has a 41% likelihood of needing MTP.

So basically, use a system that works for you. From my experience, centers that use a system tend to use ABC. But definitely pick a system, don’t leave it up to chance with the trauma surgeon. And use your trauma PI program to assess utilization to see if it’s the best tool for your center.

Related posts:

Reference: Systematic Reviews of Scores and Predictors to Trigger Activation of Massive Transfusion Protocols. Accepted ahead of print, J Trauma, 2019.

NFTI Scoring Revisited – Not Just For Triage Calculations?

Earlier this week, I wrote about a new tool for monitoring over- and under-triage for trauma programs. In place of using ISS as the metric for triggering review, the Need For Trauma Intervention (NFTI) is based on resource utilization during the initial portion of the hospital stay.

The original study was performed at a single Level I trauma center in Dallas. The authors then rolled it out as a multicenter study to test its overall reliability. However, the authors changed the focus in this work. The original paper focused on the development of a new tool to improve upon the evaluation of proper decisions to activate the trauma team. The authors have now extrapolated that their system predicts when a patient’s physiologic reserve is depleted. In turn, this should be the indicator that a trauma activation is needed.

The authors performed a convenience sample of 38 trauma centers around the US. Of these, 25 were adult only, 3, pediatric only, and 10 were combined adult/peds centers. Two years of data were collected from each. Injury severity score (ISS) and revised trauma score (RTS) were calculated for all patients. Outcomes analyzed were discharge location (home vs ongoing care), complications, and length of stay.

A complicated statistical model was adopted that evaluated the associations between higher ISS (> 15), lower RTS (< 7.84) and any positive NFTI factor. To refresh your memory, here’s the list of NFTI factors:

  • blood transfusion within 4 hours of arrival
  • discharge from ED to OR within 90 minutes of arrival
  • discharge from ED to interventional radiology (IR)
  • discharge from ED to ICU AND ICU length of stay at least 3 days
  • require mechanical ventilation during the first 3 days, excluding anesthesia
  • death within 60 hours of arrival

Here are the factoids regarding the new study:

  • Nearly 90,000 patient encounters were submitted over a 2 year period
  • The risk of experiencing a complication increased by 9x if NFTI+, 6x for ISS>15, and 5x for RTS<7.84
  • Odds of discharge to a continuing care facility was about 2.5x more likely if any of the three thresholds were met
  • Length of stay was significantly better predicted by NFTI

The authors conclude that NFTI was a better indicator of major trauma when compared to ISS and RTS. They claim that it is the best single definition because the model fit is better and that it has stronger associations with complications, discharge location, and length of stay.

Bottom line: Hmm, I’m not so sure. It’s a great idea and does allow us to drill down on those patients most in need of high-level trauma center resources. The authors admit that each tool (ISS, RTS, and NFTI) identifies some important patients that the others do not. It just seems that more of them tend to be identified by NFTI.

I always worry when complicated statistical models are needed to show these differences. This is a complex concept, so more sophisticated models may indeed be needed by virtue of the data that needs to be analyzed. Overtriage can be easily identified in many cases when NFTI- patients trigger a full trauma activation. Obvious undertriage occurs in NFTI+ patients with no activation.

But NFTI still does not obviate the need to search harder for undertriage. What about the case of a stab to the chest in the “box” region, who does not end up with a cardiac injury or hemo/pneumothorax? They would be NFTI- but mechanism positive.

How do we learn from NFTI+ patients who did not have a trauma activation. Just like using the Cribari grid, we must look at each individual chart and ask two questions:

  1. Did this patient meet any of our highest level activation criteria? If so, it is frank undertriage.
  2. If not, do we need a new criterion to catch this in the future?

So NFTI is a somewhat improved version of the Cribari grid. Sure, it can predict complications better, as well as length of stay (which may be related). But not discharge location, as claimed. As for being an indicator of depleted patient reserve, I think that’s just speculation at this point. Both tools can be used to automatically generate data for review from the trauma registry. And both will have some false negatives and positives.

My recommendation: This paper provides an academic argument that NFTI is somewhat better than the Cribari method. Now it’s time to get practical. Some enterprising trauma centers need to do a study where they use both systems side by side. How many charts for review are generated by each? How many false negatives and positives are there? How much work (abstractor / registrar time) is needed to analyze and act on the results? This is the only way we can answer the question of which one is better in the real world.

Reference: Rethinking the definition of major trauma: The Need For Trauma Intervention outperforms Injury Severity Score and Revised Trauma Score in 38 adult and pediatric trauma centers. J Trauma publish ahead of print, 2019.

NFTI: A Nifty Tool To Replace The Cribari Grid?

In my last post, I reviewed the use of the Cribari grid for evaluating over- and under-triage at your trauma center.  This technique has been a mainstay for over a decade, but has its shortcomings. The most important one is that it relies only on the Injury Severity Score (ISS) to judge whether some type of mistriage occurred.  As you know, the ISS is usually calculated after discharge, so it can only be applied after the fact.

Two years ago, the group at Baylor University in Dallas sought to develop an alternate method of determining who needed a full trauma team activation. They chose resource utilization as their surrogate to select these cases. They reviewed 2.5 years of their own registry data (Level I center).  After several iterations, they settled on six “need for trauma intervention” (NFTI) criteria:

  • blood transfusion within 4 hours of arrival
  • discharge from ED to OR within 90 minutes of arrival
  • discharge from ED to interventional radiology (IR)
  • discharge from ED to ICU AND ICU length of stay at least 3 days
  • require mechanical ventilation during the first 3 days, excluding anesthesia
  • death within 60 hours of arrival

Patients who had at least one NFTI criterion were considered candidates for full trauma activation, and those who met none were not. Here are the factoids for this study:

  • There were a total of 2260 full trauma activations and 2348 partial activations during the study period (a little over 900 per year for each level)
  • Roughly 2/3 of full activations were NFTI +, and 1/3 were NFTI –
  • For partial activations, 1/4 were NFTI + and 3/4 were NFTI –
  • Only 13 of 561 deaths were NFTI – and all had DNR orders in place

The authors concluded that NFTI provides an assessment of both anatomy and physiology using only measures of early resource utilization. They believe that it self-adjusts for age, frailty, and comorbidities, and that it is a simple and effective tool for identifying major trauma patients.

Bottom line: This is an elegant attempt to improve upon the simple (yet admittedly flawed) Cribari matrix method for assessment of major trauma patient triage. It was thoughtfully designed and evaluated at this one center. The authors recognize that it is based on retrospective data, but so is the Cribari technique. 

I believe that it may be an adjunct to Cribari. The matrix identifies gross under- and over-triage, but still requires the trauma program to review the outliers to see if mistriage actually occurred. It is basically a “first pass” that seeks to over-identify potential problem patients.

NFTI is similar, but it focuses on those patients who really should have been a full trauma activation due to their early need for critical resources to deal with their injuries. But is it enough? In my next post, I’ll review the follow-on paper from this group as they apply it to multiple trauma centers. And I’ll add some final thoughts on the subject.

Reference: Asking a Better Question: Development and Evaluation of the Need For Trauma Intervention (NFTI) Metric as a Novel Indicator of Major Trauma. J Trauma Nursing 24(3):150-157, 2017.

The Cribari Grid And Over/Undertriage

Any trauma performance improvement professional understands the importance of undertriage and overtriage.  Overtriage occurs when a patient who does not meet trauma activation criteria gets one anyway. And undertriage is the converse, where no activation is called despite criteria being met. As you may expect, the latter is much more dangerous for the patient than the former.

I frequently get questions on the “Cribari grid” or “Cribari method” for calculating these numbers. Dr. Chris Cribari is a previous chair of the Verification Review Subcommittee of the ACS Committee on Trauma. He developed a table-format grid that provides a simplified method for calculating these numbers.

But remember, the gold standard for calculating over- and undertriage is examining each admission to see if they met any of your trauma activation triage criteria. The Cribari method is designed for those programs that do not check these on every admission. It is a surrogate that allows you to identify patients with higher ISS that might have benefited from a trauma activation.

So if you use the Cribari method, use it as a first pass to identify potential undertriage. Then, examine the chart of every patient in the undertriage list to see if they meet any of your activation criteria. If not, they were probably not undertriaged. However, you must then look at their injuries and overall condition to see if they might have been better cared for by your trauma team. If so, perhaps you need to add a new activation criterion. And then count that patient as undertriage, of course.

I’ve simplified the calculation process even more and provided a Microsoft Word document that automates the task for you. Just download the file, fill in four values in the table, update the formulas and voila, you’ve got your numbers! Instructions for manual calculations are also included. Download it by clicking the image below or the link at the end of this post.

cribarigrid

Download the calculator by clicking here

In my next post, I’ll examine how the NFTI score (need for trauma intervention) fits into the undertriage/overtriage calculations.

Related posts: