Tag Archives: complications

The Second Head CT In Patients Taking DOACs

Direct oral anticoagulant drugs (DOACs) are here to stay. When they were first released, I was very concerned with our inability to reverse them. I feared that we would have a rash of our elders presenting with severe head bleeds that we could do nothing about.

Well, that has not materialized. In fact, it appears that the probability of serious bleeding is more likely with our old reversible workhorse drug, warfarin.

But we are still spooked by DOACs. Nearly every center that has a practice guideline for managing patients with TBI on blood thinners includes a repeat CT scan after a given time interval. This is typically 6, 12, or even 24 hours.

Given the evolving safety profile of DOACs, is this even necessary? The surgical group at the Henry Ford Wyandotte Hospital in Michigan performed a retrospective registry review for their Level III trauma center. They reviewed the data for all adult patients who had suspected or confirmed blunt head trauma (any mechanism), were taking a DOAC, and received at least one CT scan.

Here are the factoids:

  • There were 400 patients with 498 encounters (yes, 15% came back with another TBI)
  • Patients were elderly (mean age 76) and nearly evenly split by sex
  • Fall was the most common mechanism (97%)
  • The first scan was negative in 96% of patients;12% of them did not have a repeat scan
  • Of the 420 patients who had a second scan, 418 were negative (99.5%). The two with positive scans were discharged uneventfully.
  • There were no differences based on specific DOAC, presenting GCS or mechanism

Bottom line: This is a relatively small, single institution study. However, it does appear that the authors have a large population of elderly patients suffering falls. This paper suggests that, indeed, a second scan may not be necessary. This parallels data from my own hospital. But to be on the safe side, keep an eye out for bigger, multi-institutional studies to be sure.

Reference: The utility of a second head CT scan af-ter a negative initial CT scan in head trauma patients on new direct oral anticoagulants (DOACs). Injury, article in press, June 13, 2021.

Activity Guidelines After Solid Organ Injury: How Important Are They?

Just about every practice guideline out there regarding liver and spleen injury has some type of physical activity guidelines associated with it. The accepted dogma is that moving around too much, or climbing stairs, or lifting objects, or getting tackled while playing rugby could exacerbate the injury and lead to complications or surgery.

But is it true? Activity restrictions after solid organ injury have been around longer than I have been a trauma surgeon. And the more people I poll on what they do, the more and very different answers I get. And there are no decent papers published that look critically at this question. Until now. 

A pediatric multi-center study of study on adherence to activity restrictions was published last year. Ten Level I pediatric trauma centers in the US tabulated their experience with solid organ injuries over a 3.75 year period fro 2013 to 2016. Only patients with successful nonoperative management of their injury were included, and those with high grade renal or pancreatic injuries were excluded.

Since this was a pediatric study, the American Pediatric Surgical Association (APSA) practice guideline was followed (activity restriction = organ injury grade + 2 weeks). Activity restrictions included all sports, any recreational activity with wheels, or any activity that involved having both feet off the ground. Patients with Grade III-V injuries were seen at an office visit after 2 weeks, and lower grade injuries had a phone followup.

Adherence to guidelines was assessed by a followup phone call two months after injury. Clinical outcomes assessed at 60 days included unplanned return to the emergency department (ED), re-admission, complications, and development of new bleeding confirmed by surgery, ultrasound, or computed tomography (CT) at 60 days post injury.

Here are the factoids:

  • Of the 1007 patients in the study, some 56% were either excluded (178) or lost to followup (463)
  • Of the remaining 366, roughly 46% had a liver injury, 44% spleen, and the remaining 10% had both
  • Median age was 10, so this was actually a younger population
  • 76% of patients claimed they abided by the guidelines, 14% said they did not, and 10% “didn’t know.” This means they probably did not.
  • For the 279 patients who said they adhered to activity restrictions 13% returned to the ED and half were admitted to the hospital
  • Of the 49 patients who admitted they did not follow the guidelines, 8% returned to the ED at some point and none were readmitted
  • The most common reasons for return to ED were abdominal pain, anorexia, fatigue, dizziness, and shoulder pain
  • There were no delayed operations in either of the groups

Bottom line: There were no significant differences between the compliant and noncompliant groups. Unfortunately, the authors did not include an analysis of the “I don’t know if I complied” group, which would have been interesting. But there is one issue I always worry about in these low-number-of-subjects studies that don’t show a significant difference between groups. Did they have the statistical power to show such a difference? If not, then we still don’t know the answer. And unfortunately, I’m not able to guess the numbers well enough to do the power calculation for this study.

I am still intrigued by this study! Our group originally had a fixed time period (6 weeks) of limited activity in our practice guideline for pediatric solid organ injury patients. This was rescinded last year based on our experience of no delayed complications and guidance from our sister pediatric trauma center at Children’s Hospital in Minneapolis. We are also moving toward making a similar change on our adult practice guideline.

Too many centers wait too long to make changes in their practice guidelines. They bide their time waiting for new, published research that they can lean on for their changes. Unfortunately, I think they will be waiting for a long time because many of our questions are not interesting enough for acceptance by the usual journals. Rely on the expertise and experience of your colleagues and then make those changes. Be sure to follow with your performance improvement program to make sure that they actually do work as well as you think!

Reference: Adherence to APSA activity restriction guidelines and 60-day clinical outcomes for pediatric blunt liver and splenic injuries (BLSI). J Ped Surg 54:335-339, 2019.

Air Embolism From an Intraosseous (IO) Line

Intraosseous (IO) lines are a godsend when we are faced with a patient who desperately needs access but has no veins. The tibia is generally easy to locate and the landmarks for insertion are straightforward. They are so easy to insert and use, we sometimes “set it and forget it”, in the words of infomercial guru Ron Popeil.

But complications are possible. The most common is an insertion “miss”, where the fluid then infuses into the knee joint or soft tissues of the leg. Problems can also arise when the tibia is fractured, leading to leakage into the soft tissues. Infection is extremely rare.

This photo shows the inferior vena cava of a patient with bilateral IO line insertions (black bubble at the top of the round IVC).

During transport, one line was inadvertently disconnected and probably entrained some air. There was no adverse clinical effect, but if the problem is not recognized and the line is not closed properly, there could be.

Bottom line: Treat an IO line as carefully as you would a regular IV. You can give anything through it that can be given via a regular IV: crystalloid, blood, drugs. And even air, so be careful!

AAST 2019 #6: DOACs Part 3!

A little further down the direct oral anticoagulants (DOACs) rabbit hole please? The abstract reviewed in my last post suggested that elderly patients taking these agents actually do better than those on warfarin. So if that’s the case, do we need to be so attentive to getting followup CT scans on these patients to ensure that nothing new and unexpected is happening?

The trauma group at UCSF – East Bay performed a multi-center review of the experience at “multiple” Level I trauma centers over a three year period. They included anticoagulated patients with blunt trauma who had a negative initial head CT. Patients taking only an anti-platelet agent or a non-oral anticoagulant were excluded.  They analyzed the data for new, delayed intracranial hemorrhage, use of reversal agents, neurosurgical intervention, readmission, and death.

Here are the factoids:

  • A total of 739 records were studied: 409 on warfarin and 330 on a DOAC. Average age was 79, and half were male.
  • Repeat head CT was performed only half the time (!)
  • Delayed hemorrhage was noted in 4% of warfarin cases (9 of 224) and 2.5% of DOAC cases (4 of 159)
  • There were no interventions or deaths in the DOAC group with followup CT, or in those who did not have the repeat scan
  • There was 1 intervention in the warfarin group and two deaths attributed to TBI
  • Reversal agents were administered to 2% of DOAC patients and 14% of warfarin patients
  • The authors performed a regression analysis that showed the two strong associations with delayed hemorrhage were male sex and AIS head > 2 (!)

The authors concluded that this “largest study” suggests that DOACs “may” have a better safety profile compared to warfarin and repeat head CT is not indicated.

Now, hold on a minute!

Rule #1: No single published paper should ever change your practice. They need to be confirmed by other, hopefully better work.

Rule #2: No single abstract should make you even think about changing your practice! These are preliminary works that always need more detail, more effort, and a lot more thought. They are meant to telegraph what the authors are working on and to raise interesting questions from the audience. They should stimulate others to try to replicate and improve upon the work. In general, if something looks really good as an abstract, the next step is successful publication. This means that peers have reviewed the data and agree that it looks promising. But then it should take several years of work by the original authors and others to prove or refute the claims.

This study was small in the first place, and became smaller because half did not have repeat CT scans. The only statistically significant result was that we confirmed that the providers were not very good about getting followup scans. Just because they didn’t do it doesn’t mean it’s not indicated, especially given the nature of the data and the very small numbers.

I consider this another very small piece in the puzzle that suggests DOACs are not as evil as warfarin. There are several of these low power studies floating around right now. But we need to hunker down and really do a big study right so we can start to get a clearer picture of what we should do. For now, it’s best to treat all anticoagulants and anti-platelet agents as evil and err on the side of overtreating.

Here are my comments and questions for the presenter and authors:

  • Why was the followup head CT rate so poor? Was this a “however they like to do it” thing, was there a protocol, did the trauma centers just not believe that DOACs could be bad?
  • What were the guidelines for reversal? If the initial head CT was normal, why ever reverse? This suggests that participating centers could do whatever they wanted based on unspecified criteria.
  • Was the regression analysis helpful in any way? Being male and having a mild TBI seem rather nonspecific factors and wouldn’t help select patients for reversal or repeat scan.
  • Please provide more information on the warfarin intervention and deaths.
  • Isn’t the title of this abstract rather bold for the quality of the results presented?

I’m sure there will be some lively debate at the end of this presentation!

Reference: Repeat CT head scan is not indicated in trauma patients taking novel anticoagulation: a multi-institutional study. AAST 2019, Oral Abstract #66.

AAST 2019 #5: DOACs Part 1

A short while ago I wrote about the proper nomenclature of the new or novel oral anticoagulant medications that are replacing warfarin in patients with atrial fibrillation (click here for details). Cut to the chase, the consensus seems to be that they should be called direct oral anticoagulants or DOACs.

These medications strike fear into the average trauma professional, primarily because there is no easy way to reverse them as there is for warfarin. We are finally accumulating enough experience with them to start to see the bigger picture with respect to complications and mortality. Today, I’ll begin the discussion with a series of three abstracts regarding these drugs.

The AAST conducted a multicenter, prospective, observational study that collected DOAC trauma patient information from 15 centers. They reviewed four years of data, specifically examining the use of reversal agents and mortality.

Here are the factoids:

  • A total of 606 patients were enrolled. They were generally elderly with an average age of 75.
  • Most were taking one of the Factor Xa inhibitors (apixaban, rivaroxaban, edoxiban), while just 8% were taking the direct thrombin inhibitor dabigatran.
  • Only 1% of patients received a reversal agent (prothrombin complex concentrate (PCC) 87%, Praxbind (12%), and Andexxa (1%)
  • Those receiving reversal tended to be older than the average and had more severe head injuries
  • Patients who were reversed with PCC had no change in mortality using a regression model
  • Patients reversed with Praxbind or Andexxa had a 15x higher probability of mortality

The author’s conclusions merely restated their results.

This is fascinating information. Unfortunately, this study was not designed to provide a comparison with patients taking warfarin. However, my next two abstract reviews will cover this very topic. 

There are two interesting tidbits here. First, reversal was only carried out in about one in eight patients. Why is this? No protocol? No product? Too pricey? Patients not hurt badly enough? And how would that be judged anyway?

The second is that reversal with PCC seems to be benign, but use of one of the specifically designed reversal agents really jacked up mortality. These agents (Praxbind and Andexxa) are very expensive ($3.5K and $50K respectively). Furthermore, there are no studies anywhere that show their effectiveness. This one actually seems to show they might be dangerous.

The devil is in the details. Here are my questions for the presenter and authors:

  • Were there any guidelines for reversal? This is key because if not, the statistics just describe “how we do it.” Yes, you can tease out higher ISS or AIS head as potential reasons, but were there directions regarding this built into the study protocol?
  • Do you have any data on the success rates of PCC reversal? Were there provisions to demonstrate lesion stability vs progression after administration?
  • Do you have an impression of why the tailored reversal agents seemed to be so deadly? Were they used as a last resort due to cost. Did the centers have a hard time getting it or authorizing its use?

This abstract could be a gold mine!

Reference: The AAST prospective, observational, multicenter study investigating the initial experience with reversal ofnovel oral anticoagulants in trauma patients. AAST 2019, Oral Paper 58.