Category Archives: Performance Improvement

Undertriage And Overtriage: The Cribari Grid

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.

I frequently get questions on the “Cribari Grid” or “Cribari Method” for calculating these numbers. Dr. Chris Cribari was a previous chair of the Verification Review Committee 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 actually met any of your trauma activation triage criteria. The Cribari method is designed for those programs that do not or cannot check these on every admission. And since most programs have too many trauma admissions to verify every single one, the grid technique can be very helpful. It is a surrogate for chart review that helps reduce the workload to identify patients with higher ISS that might have benefited from a trauma activation.

If you use the Cribari method, use it as a first pass to identify potential undertriage. In most trauma programs, the raw undertriage number using the grid will be around 10-20%. Obviously, this is unacceptably high. It requires the second pass: manually examining the chart of every patient in the undertriage list to see if they meet any of your activation criteria. If they did not, they would most likely not have been undertriaged. The second pass process usually decreases the undertriage rate by about 10%, usually reducing it below the acceptable threshold of 5%

But now you need to do a third pass. Look at each patient’s injuries and overall condition to ask yourself if they might have been better cared for by your entire trauma team. Even though they don’t meet any of your existing criteria, should they have? If so, you may need to add a new activation criterion. Then, count that patient as undertriage, of course.

I’ve simplified the Cribari Grid calculation process as much as possible and have provided a Microsoft Word document that automates the task. Just download the file, fill in the four highlighted values in the table, update the formulas using the instructions, 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.

In my next post, I’ll examine how the NFTI score (Need For Trauma Intervention) fits into your undertriage calculations.

Click here to download the calculator.

Transfers In: Direct Admit vs Send To The ED

Level I and II trauma centers are frequently asked to accept patients who need a higher level of care. This necessitates an inter-hospital transfer that is subject to scrutiny by the trauma performance improvement program of both trauma centers. The practice at many centers is to bring all transfer patients in through the emergency department. But is this really necessary?

Bringing Patients To Your Emergency Department

  • Patients can be reassessed to see if they meet any of your trauma activation criteria.
  • The work-up from the referring hospital can be re-evaluated. If some testing or imaging has been omitted, it can be obtained after arrival.
  • Specialist assessment may be more timely or may involve interventions that are more difficult after leaving the ED. Here’s an example. In some hospitals, orthopedics may choose to place a traction pin to provide initial fracture management. They may choose to use sedation, which may not be as readily available on a surgery ward.
  • Access to certain critical services may be more rapid from the emergency department. A patient may be more rapidly taken to the operating room or interventional radiology if the patient is in the emergency department.
  • It is easier to determine the correct admitting service in the ED prior to the actual admission. Sometimes patients are suitable for admission to a surgical subspecialist service, or to a medical service if they have complex comorbidities. Initial admission to the correct service from the ED is easier than later transfer.

But there are a few downsides to ED arrival:

  • The emergency department may be swamped. Taking a patient who could just as easily have been admitted directly increases congestion in the ED and slows throughput even further.
  • There is a built-in time delay going through any emergency department. You can count on patients spending eight hours, if not much, much more if they come to the ED first.
  • It’s a big dissatisfier for patients. They’ve already gone through this time-intensive process once and are usually not happy to have to do it again.

Direct Admissions

Direct admissions essentially reverse the pros and cons listed for emergency department evaluation.

There is a mistaken belief that the ACS Verification Review Committee looks askance direct admissions. This is not the case, and there are no criterion deficiencies that refer to them. Direct admits may be reported on the site visit pre-review questionnaire, and the reviewers may have questions about your numbers and how you identify them. Otherwise, each center is free to choose how they handle them.


Here are some guidelines for directing incoming patients to the most appropriate place.

  • Are you familiar with the referring physician or APP? If you have worked with them before and are confident of their evaluation skills, then a direct admission could be appropriate.
  • Is the referring hospital a trauma center, and are you familiar with how they work up patients? What has your previous experience with them been? Again, if they are part of your hospital system and/or you have had successful direct admissions from them in the past, consider it again.
  • Will the patient need rapid access to specialized services after arrival? Do they need to go to the operating room quickly? Or might they need advanced imaging that can be arranged more expeditiously from the ED?
  • Will they need any procedures after arrival that are more easily done in your ED? Do they need a complicated laceration repair best done with equipment in the ED? Will they require conscious sedation for a procedure?
  • Are you unsure of the most appropriate admitting service? Does the patient have significant comorbidities? Do you have two or more potential admitting services but just need to lay eyes on the patient to help you decide?
  • How busy is your ED? The longer the wait time, the more desirable it is to just skip it altogether, especially if none of the items above apply.

But make sure that you are able to accurately identify and track each and every direct admission coming into the hospital. Although high numbers of direct admission patients is not a violation of ACS standards, allowing trauma patients to get into the hospital on non-trauma services without being identified by the PIPS program is. I recommend that you review each and every one of them shortly after they arrive. Then make sure the decision-making was correct and the patient is on the service that best meets their needs.

An Update On The Electronic Trauma Flow Sheet

It’s been five years since I published my series on the use of the electronic trauma flow sheet (eTFS). Anyone who knows me is familiar with my skepticism about this tool. I’ve been writing about the significant problems it can create since 2008! With the progress in computing power and interfaces we have enjoyed, we would have this problem solved by now.

But alas, that is not the case. There has been little progress and at great expense and aggravation for the trauma centers. Since I last published the series, I’ve visited numerous hospitals that use the eTFS and a diminishing number that have stuck with the paper trauma flow sheet. Based on this experience, I am updating the series and will republish it here over the next several weeks.

As you read each part of the series, please take a moment to post comments or questions at the end of the piece or email them to me. I will strive to address them in my updates. And I would love to hear your opinions on how this tool is working (or not) for you. If I receive enough comments, I’ll post a summary of them at the end of the series.

I’ll kick off the series with my next post, which describes why your hospital wants you to switch to some newfangled eTFS. Enjoy, or weep, as the case may be!

Blame The Trauma Surgeon?

I just finished reading a recent paper published in the Journal of Trauma that purports to examine individual surgeon outcomes after trauma laparotomy. The paper was presented at AAST last year, and is authored by the esteemed trauma group at the University of Alabama at Birmingham. It was also recently discussed in the trauma literature review series that is emailed to members of EAST regularly.

Everyone seems to be giving this paper a pass. I won’t be so easy on it. Let me provide some detail.

The authors observe that the mortality in patients presenting in shock that require emergent laparotomy averages more than 40%, and hasn’t changed significantly in at least 20 years. They also note that this mortality varies widely from 11-46%, and therefore “significant differences must exist at the level of the individual surgeon.” They go on to point out that damage control usage varies between individuals and trauma centers which could lead to the same conclusion.

So the authors designed a retrospective cohort study of results from their hospital to try to look at the impact of individual surgeon performance on survival.

Here are the factoids:

  • Over the 15 month study period, there were over 7,000 trauma activations and 252 emergent laparotomy for hemorrhage control
  • There were 13 different trauma surgeons and the number of laparotomies for each ranged from 7 to 31, with a median of 15
  • There were no differences in [crude, in my opinion] patient demographics, hemodynamics, or lab values preop
  • “Significant” differences in management and outcomes between surgeons were noted:
    • Median total OR time was significantly different, ranging from 120-197 minutes
    • Median operation time was also different, from 75-151 minutes across the cohort of surgeons
    • Some of the surgeons had a higher proportion of patients with ED LOS < 60 minutes and OR time < 120 minutes
    • Resuscitation with red cells and plasma varied “significantly” across the surgeons
  • Mortality rates “varied significantly” across surgeons at all time points (24-hour, and hospital stay)
  • There were no mortality differences based on surgeons’ volume of cases, age, or experience level

The authors acknowledged several limitations, included the study’s retrospective and single-center nature, the limited number of patients, and its limited scope. Yet despite this, they concluded that the study “suggests that differences between individual surgeons appear to affect patient care.” They urge surgeons to openly and honestly evaluated ourselves. And of course, they recommend a large, prospective, multicenter study to further develop this idea.

Bottom line: This study is an example of a good idea gone astray. Although the authors tried to find a way to stratify patient injury (using ISS and individual AIS scores and presence of specific injuries) and intervention times (time in ED, time to OR, time in OR, op time), these variables just don’t cut it. They are just too crude. The ability to meaningfully compare these number across surgeons is also severely limited by low patient numbers. 

The authors found fancy statistical ways to demonstrate a significant difference. But upon closer inspection, many of these differences are not meaningful clinically. Here are some examples:

  • Intraoperative FFP ranged from 0-7 units between surgeons, with a p value of 0.03
  • Postoperative FFP ranged from 0-7 units, with a p value of 0.01
  • Intraoperative RBC usage was 0-6 units with the exception of one surgeon who used 15 in a case, resulting in a p value of 0.04

The claim that mortality rates varied significantly is difficult to understand. Overall p values were > 0.05, but they singled out one surgeon who had a significant difference from the rest in 22 of 25 mortality parameters listed. This surgeon also had the second highest patient volume, at 25.

The authors are claiming that they are able to detect significant variations in surgeon performance which impacts timing, resuscitation, and mortality. I don’t buy it! They believe that they are able to accurately standardize these patients using simple demographic and performance variables. Unfortunately, the variables selected are far too crude to accurately describe what is wrong inside the patient and what the surgeon will have to do to fix it.

Think about your last 10 trauma laparotomies where your patient was truly bleeding to death. How similar were they? Is there no difference between a patient with a mesenteric laceration with bleeding, an injury near the confluence of the superior mesenteric vessels, and a right hepatic vein injury? Of course there is. And this will definitely affect the parameters measured here and crude outcomes. Then add some unfavorable patient variables like obesity or previous laparotomy.

In my estimation, this paper completely misses the point because it’s not possible to retrospectively categorize all the possible variables impacting “surgeon performance.” This is particularly true of the patient variables that could not possibly be captured. The only way to do this right is to analyze each case as prospectively as possible, as close to the time of the procedure and as honestly as possible. And this is exactly what a good trauma M&M process does!

So forget the strained attempts at achieving statistical significance. Individual surgeon performance and variability will come to light at a proper morbidity and mortality conference, and should be evened out using the peer review and mentoring process. It’s not time to start blaming the surgeon!

Reference: It is time to look in the mirror: Individual surgeon outcomes after emergent trauma laparotomy. J Trauma 92(5):769-780, 2022.

For PI Fans: Cribari, NFTI, And STAT!

I’ve published a two-part series on the Cribari matrix, Need For Trauma Intervention (NFTI), and the Standardized Triage Assessment Tool (STAT). These are performance improvement topics for the real nerds out there and can be found only on my Trauma PI website, TraumaMedEd.com.

If you are interested in optimizing trauma triage and trauma activations at your center, check out my posts by clicking this link:

https://www.traumameded.com/blog/