Tag Archives: pediatric

Predicting VTE Risk In Children

There’s a lot of debate about if and at what age injured children develop significant risk for venous thromboembolism (VTE). In the adult world, it’s a little more clear cut, and nearly every patient gets some type of prophylactic device or drug. Kids, we’re not so certain about at all.

The Children’s Hospital of Wisconsin tried to tease out these factors to develop and implement a practice guideline for pediatric VTE prophylaxis. They prospectively reviewed over 4000 pediatric patients admitted over a 6 year period.

It looks like the guideline was developed using some or all of this data, then tested using regression models to determine which factors were significant. The guideline was then tweaked and a final model was implemented.

Here are the factoids:

  • 588 of the patients (14%) were admitted to the ICU, and 199 of these were identified as high-risk by the guidelines
  • Median age was 10 (this is always important in these studies)
  • VTE occurred in 4% of the ICU patients, and 10% of the high-risk ones
  • Significant risk factors included presence of central venous catheter, use of inotropes, immobilization, and GCS < 9

Bottom line: This abstract confuses me. How were the guidelines developed? What were they, exactly? And the results seem to pertain to the ICU patients only. What about the non-ICU kids? The abstract just can’t convey enough information to do the study justice. Hopefully, the oral presentation will explain all.

I prefer a very nice analysis done at the Oregon Health Science University in Portland. I wrote about this study earlier this year. The authors developed a very useful calculator that includes most of the risk factors in this model, and a few more. Input the specific risks, and out comes a nice score. The only issue is, what is the score threshold to begin prophylaxis and monitoring? Much more practical (and understandable) than this abstract. Check it out at the link below.

References:

  1. Evaluation of guidelines for injured children at high risk for venous thromboembolism: A prospective observational study. J Trauma Acute Care Surg. 2017 May;82(5):836-844.
  2. A Clinical Tool for the Prediction of Venous Thromboembolism in Pediatric Trauma Patients. JAMA Surg 151(1):50-57, 2016.

How Common Is BCVI?

Blunt carotid and vertebral artery injuries (BCVI) are an under-appreciated problem after blunt trauma. Several screening tools have been published over the years, but they tend to be unevenly applied at individual trauma centers. I will discuss them in detail in the next section.

For the longest time, the overall incidence of BCVI was thought to be low, on the order of 1-2%. This is the number I learned years ago, and it has not really changed over time.

But how do we know for sure? Well, the group at Birmingham retrospectively reviewed every CT angiogram (CTA) of the neck they did in a recent two-year period. They did this after adopting a policy of imaging each and every one of their major blunt trauma patients for BCVI. Each patient chart was also evaluated to see if the patient met any of the criteria for the three commonly used screening systems.

During the study period, a total of 6,287 of 6,800 blunt trauma patients underwent BCVI screening with CTA of the neck. They discovered that 480 patients (7.6%) were positive for BCVI!

This is a shocking 8x higher than we expected! So why hasn’t this been obvious until now? Most likely because we were previously only aware of patients who became symptomatic. Luckily, many of these patients dodge the proverbial bullet and never exhibit any symptoms at all.

And what about pediatric patients? The neurosurgery groups at the University of New Mexico and Texas Children’s Hospital analyzed data in the Kids’ Inpatient Database (KID), which contains nationally representative pediatric data from the US. Five samples were obtained three years apart, beginning in 2000 and extending to 2012.

There were nearly 650,000 admissions for blunt trauma in the database, and 2150 were associated with BCVI. There was an interesting trend: incidence in 2000 started at 0.24% and increased to 0.49% in 2012. This represents a relative doubling of cases! Keep in mind that the absolute numbers remained very small, especially compared to the adult incidence.

Children aged 4 to 13 had the lowest risk of sustaining BCVI. This was higher in younger kids (ages 0-3), probably due to their big heads. It was also higher in adolescents and young adults (age 15-20). The injury was found more often in conjunction with cervical spine, skull base, clavicle, and facial fractures, as well as in children with TBI and intracranial hemorrhage.

Over one-third of children sustaining BCVI suffered a stroke (37%). Mortality was high, with a total mortality of 13%. This increased to a 20% rate if a stroke occurred.

So why should we be worried? This is one of those clinical entities like blunt thoracic aortic disruption that potentially has terrible consequences if ignored. And it seems to be worse among children even though it is far less common. Although the number of patients who develop sequelae from their BCVI is small, suffering a stroke can be catastrophic.

Should we perform a screening study for all blunt trauma patients? It seems like overkill, or is it? Is there any way we can be more selective about it?

In the next post, I’ll review the current screening tools used to determine which patients should receive CTA and how good they are.

References:

  1. Universal screening for blunt cerebrovascular injury. J Trauma 90(2):224-231, 2021.
  2. Blunt cerebrovascular injury in pediatric trauma: a national database study. J Neurosurg Pediatr. 2019

Do We Really Need To Admit Children With Low-Grade Solid Organ Injury?

Over the years, we have slowly gotten wiser about solid organ injuries (SOI). Way back when, before CT and ultrasound, if there was a suspicion a patient had such an injury you were off to the operating room. We learned (from children, I might add) that these injuries, especially the minor ones, were not such a big deal.

However, we routinely admit adults and children with solid organ injury of any grade. Many centers have streamlined their practice guidelines so that these patients don’t spend very long in the hospital, but most are still admitted. A number of researchers from Level I pediatric centers in the US got together to see if this is really necessary.

They combed through 10 years worth of TQIP data for outcomes and timing of intervention in children with low-grade (grades 1 and 2) solid organ injury age 16 or less. Children with “trivial” extra-abdominal injuries were included to make the conclusions more generalizable.  Penetrating injuries and burns were excluded, as were those with “risk of hemorrhage” or need for abdominal exploration for reasons other than the SOI. The risk of hemorrhage was defined as a pre-existing condition or other injury that made it more likely that a transfusion might be necessary for other causes.

Here are the factoids:

  • A total of 1,019 children with low-grade SOI (liver, kidney, or spleen) were enrolled in the study, and 97% were admitted
  • There was an even distribution across age groups. Many studies over-represent teenagers; this was not the case here.
  • Median LOS was 2 days, and a quarter were admitted to the ICU
  • Only 1.7% required an intervention, usually on the first hospital day (transfusion, angiography, or laparotomy)
  • Pediatric trauma centers did not perform any of the 9 angiographic procedures, and they only performed 1 laparotomy of the 4 reported

The authors concluded that practice guidelines should be developed for adult centers caring for children to decrease the number of possibly unnecessary interventions, and that it may be feasible to manage many children with low-grade SOI outside of the hospital.

Bottom line: This is an intriguing study. The admission length and silly restrictions like bed rest, NPO, and multiple lab draws are finally approaching their end. Although this paper does have the usual limitations of using a large retrospective database, it was nicely done and thoughtfully analyzed. 

It confirms that adverse events in this population are very uncommon, and that adult centers are still too aggressive in treating children like adults. The recommendation regarding practice guidelines is very poignant and this should be a high priority.

Individual centers should determine if they have the infrastructure to identify low-risk children who have reliable families and live in proximity to a hospital with a general surgeon, or better yet, near a trauma center. Hopefully this study will help accelerate the adoption of such guidelines and practices, moving treatment for many children to the outpatient setting.

Reference: Hospital-based intervention is rarely needed for children with low-grade blunt abdominal solid organ injury: An analysis of the Trauma Quality Improvement Program registry. JTrauma 91(4):590-598, 2021.

Blunt Duodenal Injury In Children

Blunt injury to hollow organs is rare in adults, but a little more common in children. This is due to their smaller muscle mass and the lack of protection by their more flexible skeleton. Duodenal injury is very rare, and most trauma professionals don’t see any during their career. As with many pediatric injuries, there has been a move toward nonoperative management in selected cases, and duodenal injury is no exception.

What we really need to know is, which child needs prompt operative treatment, and which ones can be treated without it? Children’s Hospital of Boston did a multicenter study of pediatric patients who underwent operation for their injury to try to tease out some answers about who needs surgery and what the consequences were.

A total of 16 children’s hospitals participated in this 4 ½ year study. Only 54 children had a duodenal injury, proven either by operation or autopsy. Some key points identified were:

  • The injury was very uncommon, with one child per hospital per year at best
  • 90% had tenderness or marks of some sort on their abdomen (seatbelt sign, handlebar mark, other contusions).
  • Free air was not universal. Plain abdominal xray showed free air in 36% of cases, while CT showed it only 50% of the time. Free fluid was seen on CT in 100% of cases.
  • Contrast extravasation was uncommon, seen in 18% of patients.
  • Solid organ injuries were relatively common
  • Amylase was frequently elevated

Although laparoscopic exploration was attempted in about 12% of patients, it was universally converted to an open procedure when the injury was confirmed. TPN was used commonly in the postop period. Postop ileus was very common, but serious complications were rare (wound infection <10%, abscess 3%, fistula 4%). There were 2 deaths: one child presented in extremis, the other deteriorated one day after delayed recognition of the injury.

Bottom line: Be alert for this rare injury in children. Marks on the abdomen, particularly the epigastrium, should raise suspicion of a duodenal injury. The best imaging technique is the abdominal CT scan. Contrast is generally not helpful and not tolerated well by children. Duodenal hematoma can be managed nonoperatively. But any evidence of perforation (free fluid, air bubbles in the retroperitoneum, duodenal wall thickening, elevated serum amylase) should send the child to the OR. And laparotomy, not laparoscopy, is the way to go.

Reference: Operative blunt duodenal injury in children: a multi-institutional review. J Ped Surg 47(10):1833-1836, 2012.

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.