Best Of AAST #3: Nonoperative Pancreatic Injury Management In Children

Over the years, the operative vs nonoperative management pendulum has swung to and fro. For solid organ injuries, operative management was routine until about 30 years ago. Since then, it has moved to the opposite end of the spectrum.

Similar swings have occurred in pediatric trauma management as well. Most notably it now involves that most dreaded of organs, the pancreas. In adults, this remains a problem for the operating room. But for the past 6-8 years, pediatric trauma surgeons have been dabbling with “conservative” management of pancreatic injuries.

The group at Baylor designed a prospective, multicenter study of seven pediatric trauma centers over a 2 year period. They specifically reviewed children with pancreatic injury with duct disruption (grade III). The injuries needed to be reasonably “fresh” (48 hours). They managed these children with a “Less is More” practice guideline that included early oral feeding, limited imaging and labs, and discharge based on improved symptoms. They compared their results to a previous multicenter trial performed 3-5 years earlier, before guideline implementation.

Here are the factoids:

  • There were 11 patients enrolled (!!) with a median age of 7 years
  • Clear liquids were started an average of 3.5 days postop, and a low fat diet at 6.7 days. Three patients (27%) failed to advance, requiring TPN.
  • ERCP stent was placed in 3 patients (27%)
  • Mean length of stay was 10 days
  • The authors pointed out that these numbers were all better than their published study prior to the “Less is More” guideline

Here are my comments: Unfortunately, I remember back to the days when any pancreatic injury with a duct injury, adult or child, went to surgery. For the usual, run of the mill tail transections from a handlebar injury, a quick tail resection was in order. The kids did well and were generally out of the hospital quickly (3-5 days) with few complications. I’ve operated on a handful of them, and this has been my (anecdotal) experience as well.

My concern is that, in this study, less (defined as nonop management) leads to more time to full diet, more collections and pseudocysts, and more time in the hospital.

In order to determine this, we need to know exactly how injured these 11 children were, details of their pancreatic injury, and a great deal about the data from the earlier study.  And I would be very surprised if there is sufficient statistical power to show a true difference based on only 11 patients.

Here are my questions for the authors and presenter:

  • Could some of the observed differences be due to varying grades of pancreatic injury? The abstract does not divide the kids by grade, so it is possible that some are grade III, some IV, and some are V. This makes it very difficult to tease reliable conclusions from this very small number of subjects (11).
  • Did they have other injuries as well that may have contributed to their slow recovery?
  • Have you compared your results to older research that analyzed these same variables for pediatric patients who were treated with pancreatic resection + drainage? Be prepared to compare your data to older studies, as well as to explain the details of your own historical study cited in the abstract.
  • It seems that trauma surgeons are becoming more reluctant to operate on kids. But for this injury, is that wise? Yes, the kid ends up with a scar on his abdomen. And may be missing his spleen. But what is the emotional trauma from having a tube stuck in your nose, a drain stuck in your side, or spending two weeks in the hospital? And maybe coming back for more touch-ups? Is this really better then a short one-time stay in the hospital.

There will be a lot of interest in your paper at the meeting. I can’t wait to hear you present it live!

Reference: Outcomes of standardized non-operative management of high-grade pnacreatic trauma in chilren: a study from the Pediatric Trauma Society Pancreatic Trauma Study Group. AAST 2020 Oral Abstract #6.

Best Of AAST #2: REBOA And Unstable Pelvic Fractures

REBOA is the new kid on the block. Human papers first started appearing in the trauma resuscitation literature about six years ago. Since then, we’ve been refining the details: how to use it, who to use it in, as well as a lot of the technical tidbits.

The group at Denver Health Medical Center compared their experience with pelvic packing vs REBOA for patients with unstable pelvic fractures. They reviewed four years of experience to see if they could further clarify some of the benefits of this technique.

Here are the factoids:

  • A total of 652 patients presented with pelvic fractures, and 78 underwent pelvic packing for control of hemorrhage
  • Of these 78 patients, 31 also had a REBOA catheter placed and 47 did not
  • The ISS in the REBOA+ group was significantly higher at 49 vs 40
  • Although systolic blood pressure and heart rate were statistically more abnormal in the REBOA+ group, these values were not clinically different (SBP 65 vs 72, HR 129 vs 117)
  • The amount of transfused red cells and plasma was twice as high in the REBOA+ patients (RBC 16 vs 7, FFP 9 vs 4)
  • There was no difference in survival rate (REBOA 84% vs packing 87%)

The authors concluded that this study suggests REBOA plus pelvic packing provides life-saving hemorrhage control in otherwise devastating injuries.

Here are my comments:  So the authors inserted REBOA catheters in addition to pelvic packing in half of their patients that were more severely injured, gave them twice as much blood product, and had the same number of survivors. But the primary outcome was the same. It’s very difficult to tease out which factors are responsible when there are such significant differences between the groups with respect to factors that have a definite impact on survival.

Did the use of REBOA equalize survival in the more severely injured patients, or was it the additional blood products, both, or neither? It’s really not possible to say. REBOA may be a valuable adjunct to trauma resuscitation, but we still need more information so we can be sure we are using it in the right patients.

And some questions for the authors:

  • How did you select patients for REBOA? This could make a big difference and inject significant selection bias. Could your surgeons have been primed to use this in patients who looked sicker?
  • Have you considered matching subsets of your patient groups with similar ISS and transfusion volumes, and then comparing mortality? This could be revealing, but I suspect the numbers will be too small to have the statistical power to show any differences.

This will be a very interesting paper to listen to! I look forward to more details.

Reference: Inflate and pack! Pelvic packing combined with REBOA deployment prevents hemorrhage related deaths in unstable pelvic fractures. AAST 2020 Oral Abstract #4.

Best of AAST #1: What Has The MTP Bought Us?

Let’s kick off my reviews of AAST 2020 abstracts with a paper on the results of recent advances in hemorrhage control. Over the past 10+ years we have seen the following new (and old) tools move into more widespread use:

  • Massive transfusion protocol (MTP) with a goal of 1:1 ratios of red cells to plasma
  • Availability of liquid plasma for more rapid use in the MTP
  • Addition of tranexamic acid (TXA) to resuscitation
  • Resurgence of tourniquet use by prehospital providers
  • Adoption of REBOA and TEG
  • Transfusion with whole blood

The authors analyzed their experience after serially introducing these tools to their resuscitation strategies, and studied their impact on overall mortality.

They retrospectively reviewed the experience over a 12 year period at their large Level I trauma center. Here are the factoids:

  • The reviewed a total of 824 MTP events. To put this into perspective from a volume standpoint, this is a little over one MTP activation per week.
  • Patients were primarily young (median age 31), male (81%), with a penetrating mechanism (68%). Median ISS was 25
  • Prehospital times were significantly longer at the end of the study, but the authors state that there was no correlation with an increase in in-hospital mortality
  • During the entire study, overall mortality ranged from 38% to 57%, and logistic regression did not identify an effect from any of the interventions

The authors concluded that their mortality rates have not improved despite all of the advancements we have added over the past decade. They suggest that future efforts should attempt to move targeted hemorrhage control backwards in time, out of the ED and toward to injury scene.

Here are my comments: This is an interesting and simple-appearing study. Overall, the authors didn’t really show that any of our “modern” resuscitation interventions did much for their patients at all.  There was a suggestion that tourniquet implementation and use of whole blood tended toward improving things.

But don’t be fooled by simplicity. There are many, many factors that enter into whether an individual patient lives or dies. When you fail to see a significant result in a study, first look at the methods and tools used for measurement. Are they powerful enough to discern changes? Do they cover enough of the factors that promote survival, not just our resuscitative advances? Or is the tool looking at the wrong things?

One big difference at this center is the sheer volume of penetrating trauma. This could have a major impact on survival, and may be very different from the experience of most centers that have predominantly blunt injury mechanisms.

And some questions for the authors:

  • What exactly is your definition of mortality? Made it out of the ED? Lived twenty four hours? Thirty days? This makes a big difference in how you look at the results.
  • Since you have only about one MTP event per week, do you think your numbers are large enough to actually detect a mortality difference? 
  • Did you consider looking at your unexpected survivors to see if there were any common threads in their care that might have made the difference? Maybe some of our resuscitative advances do make a difference, but only in specific subsets of patients.
  • Can you speculate about the reasons for longer prehospital times, and the impact on mortality?
  • How would you recommend pushing hemorrhage control back toward the scene? New tools for prehospital providers? More advanced providers in the rigs? This is an intriguing concept and it would be interesting to hear your thoughts.

This is a thought provoking paper that questions our assumptions about our time-honored resuscitation tools. I look forward to hearing it live next month!

Reference: After 800 MTP events, mortality due to hemorrhagic shock remains higha nd unchanged despite several hemorrhage control advancements; is it time to move the pendulum? AAST 2020 Oral Abstract #1.

The Best Of The AAST 2020

The 79th Annual Meeting of the American Association for the Surgery of Trauma starts in just three weeks! As usual, I will select a number interesting abstracts from the bunch to review. I’ll go over the findings of the research, critique it, and then provide a series of questions for the presenter to consider. These questions are ones that members of the audience may very well ask (hint, hint).

And FYI, I always send a heads-up to the presenters with a link to the post so they can study up beforehand!

I’ll begin posting my commentary on the best abstracts on a daily basis, starting tomorrow. And if you see things in them that you think I have missed the mark on, please feel free to comment!

ED Thoracotomy: Kids ARE Just Small Adults

You’ve undoubtedly read this trite phrase somewhere in your training: “Kids aren’t just small adults!” There are many examples where this is absolutely true. Think about arterial extravasation in solid organ injury. Or severe traumatic brain injury. There are major differences in treatment aggressiveness for both of these.

But what about the code situation? I’ve noted a peculiar phenomenon over the years with regard to pediatric codes of all kinds. Adults tend to persist far longer at resuscitative efforts over children than they normally would on other adults. And what about that most extreme code situation, the emergency thoracotomy?

I’ve also seen the use of this procedure in children who don’t meet the usual adult criteria. But they are kids, right? They can bounce back from more severe insults, right? I hope that I’ve convinced you over the years that one can’t just assume and generalize anything. Things that seem like so much common sense often turn out to be wrong. Think back to the days of the stress / spicy food theory of peptic ulcer disease. This seems so silly now that we recognize the role of H. Pylorii.

Scripps Mercy adult and Rady Children’s Hospital pediatric trauma centers in San Diego performed an extensive review of the National Trauma Data Bank over a three year period. They focused on patients 16 years of age or less who underwent ED thoracotomy within 30 minutes of arrival at the trauma center. They focused on procedure indications and the eventual outcomes.

Here are the factoids:

  • A total of 114 patients were recorded in the NTDB, with a mean age of 10 years and median Injury Severity Score of 26 (this is the three year experience in the entire US in three years!)
  • Males were disproportionately involved at 69%, although this is less than in adults
  • Thoracotomy was performed promptly, with a median time after arrival of 5 minutes
  • Mechanism of injury was almost evenly split between penetrating (56%) and blunt (44%)
  • Blunt mechanism mortality was 94% vs 88% for penetrating
  • Penetrating injury outside of the thorax was uniformly fatal
  • Patients without signs of life on arrival, regardless of mechanism, also had a 100% mortality rate
  • Treatment at an adult trauma center, freestanding pediatric center, or combined center had no impact on these dismal outcomes

Bottom line: This is an interesting paper, and shows that the outcomes after ED thoracotomy in kids is even more dismal than in adults. This is particularly true for children arriving without vital signs and for penetrating abdominal trauma.

However, the authors go on to suggest a practice guideline for pediatric emergency thoracotomy similar to the EAST adult guidelines based on their study findings. However, I think this is ill advised. Have a look at the absolute numbers:

The largest subgroup has only 29 patients in it. These numbers are way too small to consider a guidelines change.

This paper shows that kids are just small adults when it comes to ED thoracotomy. And they seem to do even more poorly with no vital signs or penetrating injuries outside of the chest. So think carefully the next time you must consider this procedure in a child.

Reference: Nationwide Analysis of Resuscitative Thoracotomy in Pediatric Trauma Time to Differentiate from Adult Guidelines? J Trauma published ahead of print, July 6, 2020.