Zworth Reading
EMMax’s EM Weekly Update
Highlight of the Week
Azithromycin for Preschoolers with Wheezing in the Emergency Department
New England Journal of Medicine · RCT (LOE 2)
Multicenter RCT randomized 840 preschoolers (18-59 months) presenting to the ED with moderate-to-severe wheezing to azithromycin 12mg/kg daily x5 days vs placebo. Primary outcome was symptom severity over 5 days measured by validated diary scores. Trial stopped early for futility. No difference in symptom scores between azithromycin and placebo in either bacteria-positive (62% of cohort) or bacteria-negative patients. Secondary outcomes (ED LOS, hospital LOS, 72-hour return visits) also showed no difference. Azithromycin did clear nasopharyngeal bacteria (59% vs 11%) but this microbiological effect translated to zero clinical benefit.
This is a well-designed, adequately powered multicenter RCT with appropriate blinding, placebo control, and a patient-oriented primary outcome. The early stopping for futility actually strengthens the conclusion. The question for me is whether this trial really needed to be done in the first place. The 62% bacteria-positive rate confirms these organisms are common in wheezing preschoolers, but their presence doesn't mean they're causing the wheeze or that killing them helps. This challenges the observational data that drove antibiotic prescribing in this population.
Bottom line: Azithromycin does not improve outcomes in preschool wheezers, even when pathogenic bacteria are present. Not practice changing but worth knowing. Most of us are not doing this anyway.
Practice-Changing EM
Systematic Review of Pediatric Ketamine in Emergency Department Procedural Sedation: Frequency and Predictors of Adverse EventsLOE 1 (Systematic Review)
Annals of Emergency Medicine
In children receiving IV ketamine for ED procedural sedation, what is the frequency of adverse events and what predicts them?
Across 67,871 pediatric sedations from 20 studies: zero deaths, zero permanent neurologic deficits. Sentinel events (intubation, CPR, aspiration, pressors) occurred in 1 per 11,558 sedations. Serious adverse events (including bag-mask ventilation, oral airway, insufficient sedation) occurred in 0.34%. Three modest predictors identified: age ≥10 years, URI symptoms, and coadministered opioids—each adding roughly 1 extra serious event per 100-150 sedations. Coadministered benzodiazepines were NOT a predictor of harm.
This is an update to a previous SR on the same topic. The 250-subject minimum for inclusion filters out underpowered noise. The numbers are large enough that the safety signal is robust. The finding that benzos don't increase risk is important, contradicting older concerns and potentially supporting their use for emergence reactions. The URI finding is real but the NNH of ~110 means it's a consideration, not a contraindication. This is pooled observational data, so confounding exists, but for safety outcomes in procedural sedation this is as good as evidence gets.
Bottom line: IV ketamine for pediatric procedural sedation is extraordinarily safe. This systematic review of nearly 68,000 sedations confirms what we believed but now with definitive numbers. Use it confidently. Don't withhold for mild URI. Benzos are fine.
FOAM Radar
Kratom in the ED: Pearls and PitfallsKnowledge translation / clinical review
emDocs · LOE 5 (case reports, pharmacology review, expert synthesis)
Practical overview of kratom (Mitragyna speciosa) toxicity for ED clinicians. Covers the dual opioid-agonist and stimulant effects at different doses, recognition of kratom-specific presentations, and management pearls including that naloxone may partially reverse effects but response is inconsistent.
Bottom line: Useful primer on an increasingly common toxidrome. The evidence base is thin (mostly case reports) but the clinical framework is practical. Worth 10 minutes if you haven't seen kratom toxicity yet.
Beyond the Belly: Expanding your Aortic PoCUSSkills-based education / technique review
EMOttawa · LOE 5 (expert technique demonstration)
Extends standard AAA scanning to include hepatic window, parasternal long-axis, and suprasternal notch views for more complete aortic assessment. Focuses on improving detection of thoracic pathology and dissection that standard abdominal views miss.
Bottom line: Solid technique post for expanding your aortic POCUS toolkit. The suprasternal view for arch dissection is underutilized. Reminder however that suprasternal views are more of a 'rule in' test and cannot exclude dissection.
Adjacent Specialties
Airway Management in Critically Ill Patients with ObesityLOE 5 (Narrative review / expert consensus)
Intensive Care Medicine · Critical Care / Airway
How should airway management be optimized in critically ill obese patients?
Key recommendations: NIV from pre-oxygenation through to laryngoscopy to extend safe apnea time; assess RV function before induction given sensitivity to positive pressure; videolaryngoscopy should be routine; both ketamine and etomidate are acceptable induction agents; consider awake intubation in selected patients.
This is expert synthesis, not new evidence. The physiologic rationale is sound—reduced FRC, rapid desaturation, RV strain with positive pressure transition. In an ED setting I suspect many of us will not have the time not ability to assess RV function before intubating these patients. The NIV-through-laryngoscopy approach is increasingly standard but not universally practiced. No randomized data comparing induction agents in this population. The review acknowledges key knowledge gaps honestly.
Bottom line: Useful framework for the obese difficult airway. Nothing new, but a good reminder: pre-oxygenate aggressively with NIV, use video, respect the hemodynamics. Also a good prompt to read up on awake intubation and look into whether your department has equipment and processes to support this.
Methodology Flag
Prehospital Emergency Care
Large dataset (16,550 patients) with headline finding that IM naloxone is superior to IN, which could influence EMS protocols and naloxone distribution programs.
- Confounding by indication: EMS clinicians choose route based on patient factors not captured in the dataset. Sicker patients may get IM (faster onset needed) or IN (no IV access yet). The direction of this bias is unknowable.
- Transport refusal as outcome: Lower transport rates in IM group are presented as favorable, but could reflect more precipitated withdrawal leading to patient-initiated refusal, or simply faster reversal allowing earlier refusal.
- No dose standardization: IN and IM naloxone come in different concentrations and volumes across EMS systems. The study does not account for whether 'IN naloxone' means 2mg, 4mg, or 8mg.
- Unmeasured confounders: Fentanyl vs heroin, polysubstance use, time from exposure, and witnessed vs unwitnessed events are not reliably captured but dramatically affect response to any naloxone route. Then again, we usually don't know what a patient has taken when administering naloxone.
What it does contribute: This is the largest real-world comparison of naloxone routes in EMS. It confirms that IM naloxone does not cause more documented agitation or vomiting than IN, which addresses a common concern. The lack of cardiac arrest difference is reassuring for both routes. The data support that both routes are reasonable in the prehospital setting, and that IM MAY be more effective.
Bottom line: This study cannot establish that IM is superior to IN naloxone—the observational design and outcome definitions mean we should use caution drawing conclusions.