Popular Dehydration Scales Fare Poorly In 3rd-World Use

I like the author’s use of the word “popular” to describe pediatric clinical dehydration scales.  In case you’re not part of the “in crowd”, today’s “popular” dehydration scales include the World Health Organization scale, the Gorelick scale, and the Clinical Dehydration Scale.
This article is a prospective application of each of the three scales by a healthcare provider upon admission to one of three hospitals in Rwanda.  Children were weighed on admission and then on discharge, and the gain in weight was used as the gold standard for comparison to each standardized dehydration scale.
So, bad news:  each of these dehydration scoring scales is too complicated to hold in working memory, and you’d have to have it posted on a wall.
But, good news:  in the words of the authors, “The WHO scale, Gorelick scale, and CDS did not have an area on the ROC curve statistically different from the reference line.”
Which means, you get to save your wall space because the dehydration scales gave false negatives or false positives as frequently as they gave true negatives and true positives.  More research is necessary to derive more accurate clinical assessment of children presenting with possible dehydration.
“Comparing the accuracy of the 3 popular clinical dehydration scales in children with diarrhea.”

New Pediatrics UTI Guidelines

For children between 2 and 24 months of age, the relevant high points for EM:
 – Don’t use bag urines.  Catheterization or suprapubic aspiration is the only acceptable way to make a diagnosis.  However, if you’re stuck, and you have to use a bag, a completely normal bag urine is diagnostic.
 – Send a culture to definitively establish the diagnosis based on pyuria and/or bacteruria and the presence of at least 50,000 CFU/mL of a uropathogen.
 – Oral antibiotic recommendations listed include amoxicillin-clavulanate, trimethoprim-sulfamethoxazole, and a range of oral cephalosporins for at least 7 days.  They do not have any evidence to compare 7, 10, and 14 day courses.  Nitrofurantoin is not appropriate.

Nothing terribly earthshaking – seems all pretty reasonable.

“Urinary Tract Infection: Clinical Practice Guideline for the Diagnosis and Management of the Initial UTI in Febrile Infants and Children 2 to 24 Months.”
pediatrics.aappublications.org/content/early/2011/08/24/peds.2011-1330

iPhone Medical Apps To The Rescue

In this study, the author and creator of “PICU Calculator” for iPhone details the superiority of a medical student with a smartphone over an attending using the pharmacy reference book.  A few entertaining tidbits from their main results:
 – Medical students don’t know how a book functions – failed to correctly complete any pediatric dosing task using the British National Formulary for Children.
 – Residents and attendings managed to make the book work for them about half the time.
 – Overall across all levels of training, 35 for 35 in correct dosage and volume using the iPhone app – with a mean time savings of over 5 minutes.

So, when the author of an iPhone app choses a clinical task his app is designed to replace, it works great!  But, the larger point – as we already knew – there is a role for well-designed point-of-care electronic tools, so we shouldn’t give up on our CPOE and EHR kludge so soon.

“Students prescribing emergency drug infusions utilising smartphones outperform consultants using BNFCs.”
www.ncbi.nlm.nih.gov/pubmed/21787737

Good Thought, But It’s Not Pertussis

A Swiss study in which only 2.5% percent of 1,049 pediatric ambulatory and hospitalized patients presenting with a cough-illness and who were tests for pertussis were culture positive for B. pertussis or parapertussis.  Probably a relatively accurate picture of the general prevalance of pertussis in a non-outbreak situation.  They additionally report that viral superinfection is rare enough to be coincidental – 0.6% – although the authors do note other studies have reported higher incidence, particularly in RSV+ hospitalized children <6 months of age.

So, this data is out the window if there’s an outbreak situation, but the overall clinical take home is that, yet again, our index of suspicion may be too high for an infrequently diagnosed condition – and we should moderate testing in the lower acuity cases.

“Bordetella pertussis and Concomitant Viral Respiratory Tract Infections are Rare in Children With Cough Illness.”
www.ncbi.nlm.nih.gov/pubmed/21407144

It’s Impossible To Catch All Pediatric Pneumonia

Another glass half-full vs half-empty, depending on how you read it.  Their editor capsule summary says “Children without hypoxia, fever, and ausculatory findings are low risk.”  The numbers say – in the absence of hypoxia, fever, or focal ausculatory findings, radiographic pneumonia was seen in 7.6% (CI 5.3-10.0).  Interesting numbers that, to me, say that pediatric pneumonia is still a black box of uncertainty.

However, what the authors call “definite” pneumonia was only 2.9% in the absence of those findings, and the editor’s capsule conclusion is that low-risk patients are best served by follow-up rather than radiology.  And, this is where the half-full/half-empty comes in – because a lot of EPs don’t want to the guy that sends home pneumonia even in a “low risk” situation, given than 30% of their pneumonia diagnoses required admission.  I’d rather take the half-full approach – recognizing that the majority of radiographic pneumonias are viral anyway, and, if the patient has adequate follow-up and tunes up nicely, do my best to avoid unnecessary testing in a low pretest probability setting that will end up with more false positives and unnecessary antibiotics.

“Prediction of Pneumonia in a Pediatric Emergency Department”

It’s Not An Abscess (Yes It Is)

These studies pretty much all end up saying the same thing – academic faculty can’t agree on the presence or absence of differentiating characteristics between abscess and cellulitis.  This particular study is in a pediatric population, and, there’s a lot of kappa and absolute agreement to comb through in their tables, but, basically, about 20% of the time two attendings substantially disagreed.  The authors then follow this up by observing that an I&D was performed 75% time, and purulent material was found 92% of the time.

The best conclusion from this might be – if there’s some ambiguity, put a scalpel in it.  I’d say this is reasonable – because we’ve seen a hundred times the child who bounces into the ED on day 3 of cephalexin for cellulitis because what he really had was a MRSA abscess to begin with.

Or, if you have an ultrasound with a high-frequency probe, you might be able to differentiate homogenous hyperemia from fluid collection.

“Interexaminer Agreement in Physical Examination for Children With Suspected Soft Tissue Abscesses”
www.ncbi.nlm.nih.gov/pubmed/21629150

Video Education For Emergency Departments

I know you can’t get published if you say something like “Our intervention is probably not useful and serves only as a cautionary tale for other wayward sailors”, but it still bothers me when you stretch the conclusions out by saying that an intervention that is probably not better than the control group “appears promising”.

This is a group that looked at the best way to improve parent education in pediatric asthma encounters in the Emergency Department.  They compared a video-based education program to a written handout and found…it didn’t make much difference.  They had two groups of parents, those with “low health literacy” and those with “adequate health literacy”.  The low literacy group improved a ton regardless of which educational modality was used.  The adequate literacy group barely budged with written and had a little bit more of bump with video – but the relative change in their level of literacy really wasn’t anything to write home about and they don’t try to offer an explanation for why intelligent people derive no benefit from written education.

But it doesn’t stop them from stating it “appears promising” – which, I suppose, means it’s probably better than not educating people at all, or potentially educating the illiterate.

“Parental Health Literacy and Asthma Education Delivery During a Visit to a Community-Based Pediatric Emergency Department.”
http://www.ncbi.nlm.nih.gov/pubmed/21629152

Send Children With Negative CTs Home

We should all love PECARN.  I love PECARN (Pediatric Emergency Care Applied Research Network) – and not just because I helped set it up as a research assistant peon before medical school.  I love it because it takes multicenter enrollment cohorts to conduct adequately powered research in a population that is rarely affected by serious morbidity and mortality.

Of 13,543 children with GCS 14 or 15 and a normal CT scan, none needed neurosurgical intervention in their follow-up period.  A small handful of these patients had a repeat CT or MRI for some reason, and between 10-25% of the hospitalized patients and 2-10% of the discharged patients had an abnormal result on repeat imaging.  None led to any intervention…which then, of course, begs the question whether it was appropriate to perform a test that did not result in meaningful change in management.  But, there’s not enough patients in this group to draw conclusions as to whether repeat scans should or should not be performed.

My only caveat – when you take an over-utilized test in which nearly all patients are certainly fine and will continue to be fine, you actually dilute its external validity to the patient population that really matters.  However, even in a higher-risk patient population in which CTs are used far more conservatively, the clinically relevant answer is still going to be same – the only reasonable practice is still going to be to discharge these patients home.

“Do children with blunt head trauma and normal cranial tomography scan results require hospitalization for neurologic observation?”
www.ncbi.nlm.nih.gov/pubmed/21683474

Surfactant for Hydrocarbon Aspiration

I’ve seen surfactant administered for alveolar collapse following near-drowning, but this is a case report regarding surfactant use in severe pneumonitis after low viscosity/low volatility lamp oil.  Less than 1mL of similar aspirated hydrocarbons may result in significant lung injury.  In their specific case they administered 80 mL/m2 of surfactant intratracheally as rescue therapy when their patient continued to become hypoxemic despite recruitment maneuvers on mechanical ventilation.

Definitely something to keep in mind depending on the pathophysiology of the lung injury.

“Early administration of intratracheal surfactant (Calfactant) after hydrocarbon aspiration.”
http://www.ncbi.nlm.nih.gov/pubmed/21624880

Kids Are Too Fat For The Broselow Tape Now

Now that increasing numbers of children are overweight and obese (up to 36% of 10 to 17 year olds now), 53% of this pediatric sample from West Virginia fell out of the Broselow tape estimate based on height.  Of these, 77.1% of the incorrect weights were greater than that predicted by the Broselow.

It is West Virginia – not the healthiest state in the U.S. – but any hospital that serves a predominantly disadvantaged population may have similar results, and should realize that they may be under dosing their medications.  The authors suggest only a couple alternative strategies, but I think we’re probably just best off using clinical judgement as to whether the tape is accurate in each individual clinical situation.

“Is the Broselow tape a reliable indicator for use in all pediatric trauma patients?”
http://www.ncbi.nlm.nih.gov/pubmed/21629149