Pediatric Small Talk – Evaluating Myths in Pediatric Emergency Medicine

Welcome back to Small Talk.  Every first Wednesday of the month we will release high yield PEM content written by PEM talent from around the country.  We hope you enjoy these reviews. Comments, questions, accolades or concerns: feel free to reach out to Joe Ravera, MD (pemgemspod@gmail.com).

Author: Joe Ravera MD (@pemuvm1, Director of Pediatric Emergency Medicine, Assistant Professor of Surgery, Division of Emergency Medicine, University of Vermont Medical Center) // Reviewed by: Alex Koyfman, MD (@EMHighAK); Brit Long, MD (@long_brit)

Mythology has been a part of humanity long before the advent of western medicine.  While I am by no means an expert in mythology, there are often two core themes of myths that translate well to medical mythology.  Take, for example, the story of Prometheus stealing fire for humanity, at its most basic level it is an explanation for how something occurred.  For people in ancient Greece this myth answered the question- “how did we get fire?”.   This is akin to physicians today saying, “we need to keep this child NPO prior to procedural sedation”.  In addition to explaining the rationale for an event, mythology is often coupled with an admonition against a certain behavior.  Considering the punishment of Prometheus, the story is a warning to those who would defy the Gods.  Again, hearing “this kid with croup is only mild, so if we give racemic epinephrine, we have to observe them and who wants to do that?” is a warning call to physician’s to be carful as going against common recommendations as it might lead to a terrible outcome.

Like most mythology, medical mythology, is often rooted in truth, which makes parsing out the correct practice difficult.  However, in some cases there is evidence for the exact topic in question and familiarity with this literature allows us to review and critique it, while at the same time questioning the myth and possibly changing our practice.

This Small Talk review will take a little different form, as we examine a trilogy of myths, and if you prefer the podcast version can be found here at https://pemgems.com/491-2/.

Myth #1: “In the inconsolable infant a fluorescein exam should be performed to evaluate for a corneal abrasion”

The History:  Even for experienced EM physicians, the inconsolable child is a diagnostic challenge.  Terrible things like sepsis, non-accidental trauma and intra-abdominal disasters can look very similar to less concerning presentations like a hair tourniquet.  Out of this concern, comes the dictum “we need to look everywhere and figure out why this baby is upset.”  Corneal abrasions are painful, and a fluorescein exam is not particularly harmful- just annoying to do- so just practice due diligence and check.

The Study To Make Us Think:  A very simple, yet ingenious, study was performed by Shope et al. in 2010. They performed fluorescein examinations 96 asymptomatic infants (age 1-12 weeks) presenting for well child visits and found that nearly half, 49 percent, had corneal abrasions.  While the initial aim of the study was more interested in fingernail length as it relates to corneal abrasions, this incidental finding has ramifications for the crying neonate.

The Bottom Line: If half of asymptomatic newborns have abrasions, how do we interpret findings in the context of a child in the ED at 2am who won’t stop crying. When we look for corneal abrasions, what we really care about is an explanation of the inconsolability. The fact that this is present nearly 50 percent of the time calls in to question its utility as a test.  To stop investigating for a serious cause in a child with a concerning history or exam even with a corneal abrasion is probably not advised.  On the other hand, in less concerning presentations, i.e. the child who was inconsolable but is now fast asleep, the presence of an abrasion may or may not have been the reason for the inconsolability.  In the absence of direct trauma to the eye, the corneal exam provides little reassurance in the inconsolable child and can probably be omitted.

Myth #2: “Racemic epinephrine should only be given in croup if there is stridor at rest”

The History:  Racemic epinephrine is an effective treatment for croup (or really any cause stridor).  In the 50’s and 60’s it was observed that some patients with stridor decompensated several hours after receiving racemic epinephrine. It is important to note that these patients were a heterogeneous group that included viral croup and more severe pathologies like bacterial tracheitis, and epiglottitis.  Given the observed delayed decompensation the concept of “rebound stridor” was created.  This idea led to periods of prolonged observation for any child receiving racemic epinephrine with many children admitted and observed if they received even one dose. Over time the period of observation has been shortened, to 6 hours, and now maybe even shorter, but the tenet remains only give racemic epinephrine to those that “really need it” otherwise they are stuck in your ED.

The Study To Make Us Think: A Cochrane review by Bijornsen et al. looked the effect of nebulized epinephrine on croup using a clinical scoring system.  Aligning with what we see in clinical practice there was an objective improvement in croup scores at 30 minutes, but this effect was not seen at 2 or 6 hours.  More importantly there was no evidence of a worsening or “rebound effect”.  It should be noted, that the number of studies that specifically looked at this question all had fairly small sample sizes.

The Bottom Line: The best available evidence indicates that after racemic epinephrine a child will be back to their clinical status at 2 hours without a “rebound phenomenon”.  If a child looks well enough to discharge, i.e. mild stridor with agitation, then a dose of racemic epinephrine and discharge may be appropriate without a period of observation as the chance of precipitous decline is unlikely. The decision to observe should be based on the pre-administration exam of the child and not the fact that they received racemic epinephrine.

Myth #3: “A child must be NPO for 6 hours prior to a procedural sedation”

The History: Aspiration during sedation can be a devastating complication and given this many anesthesia societies recommend a period for the patient to be NPO surgery (and certainly elective surgery) to help mitigate this risk.  This recommendation trickled down to the emergency department as part of granting EM physicians the privilege to perform procedural sedation.

The Study To Make Us Think:  As part of a large registry of pediatric sedations in Canada, Bhatt et al. in 2018 evaluated the association of poor outcomes as it related to pre-procedural fasting in the emergency department.  Their outcomes ranged from minor (e.g., vomiting) to major (e.g., significant aspiration).  These authors did not find any association with the kids’ NPO status and the chance of an adverse event. There is a slight caveat with the power of the study as major adverse events are rare, and the number of children with full meals with-in 2 hours before sedation was low in this cohort.

The Bottom Line: In the largest study to date with over 6,000 children there is no evidence that children need to be NPO for the short, mostly ketamine, procedural sedations performed in the emergency department.  This has major implications on ED flow as we do not need to hold these kids in a bed for several hours waiting for them to meet an arbitrary NPO timeline.  As a further downstream effect, children are often referred to the ED for a procedure requiring sedation (laceration, fracture, etc.). Sometimes the instructions given by the referring clinician are to remain NPO for possible sedation.  If the ED is particularly impacted there can be a long delay and leaving a kid hungry often makes placing the IV for sedation more difficult. The best available evidence is that a small snack has no impact on the need for sedation and providing this education to our referring clinicians can help alleviate the dreaded, hangry child.

Take Home Points:

• Corneal abrasions are common in asymptomatic neonates, be careful attributing it as the reason for a neonate’s inconsolability.
• The effect of racemic epinephrine is not sustained at 2 hours. Decision for disposition should be made based on the pre-administration exam, not the fact they were given a treatment.
• There is no association between a child’s NPO status and the rate of adverse events in procedural sedation.  Let them eat (a small amount of) cake.

References:

• Shope TR, Rieg TS, Kathiria NN. Corneal abrasions in young infants. Pediatrics. 2010 Mar;125(3):e565-9. doi: 10.1542/peds.2008-2023. Epub 2010 Feb 8. PMID: 20142290.
• Bjornson C, Russell K, Vandermeer B, Klassen TP, Johnson DW. Nebulized epinephrine for croup in children. Cochrane Database Syst Rev. 2013 Oct 10;(10):CD006619. doi: 10.1002/14651858.CD006619.pub3. PMID: 24114291.
• Bhatt M, Johnson DW, Taljaard M, Chan J, Barrowman N, Farion KJ, Ali S, Beno S, Dixon A, McTimoney CM, Dubrovsky AS, Roback MG; Sedation Safety Study Group of Pediatric Emergency Research Canada. Association of Preprocedural Fasting With Outcomes of Emergency Department Sedation in Children. JAMA Pediatr. 2018 Jul 1;172(7):678-685. doi: 10.1001/jamapediatrics.2018.0830. Erratum in: JAMA Pediatr. 2018 Aug 1;172(8):787. PMID: 29800944; PMCID: PMC6137504.