UMEM Educational Pearls

Title: P:F vs S:F Ratio

Category: Critical Care

Keywords: Oxygenation, ARDS, P:F Ratio, S:F Ratio, Hypoxia, Mechanical Ventilation (PubMed Search)

Posted: 4/21/2026 by Mark Sutherland, MD (Updated: 4/22/2026)
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PaO2 to FiO2 (P:F) ratios, are often considered the gold standard in critical care for assessing the degree of oxygen-refractory hypoxia in various pathologies, particularly ARDS.  P:F does have some limitations, including not accounting for the PEEP, but probably the most limiting is that it requires collecting an ABG, which is invasive and not always feasible or a top priority when resuscitating a critically ill hypoxic patient.  On the other hand, SpO2 (pulse ox saturation) is routinely available, and of course the FiO2 should be known, so many have suggested perhaps using an SpO2 to FiO2 (S:F) ratio instead.  But how S:F maps to P:F and how well they correlate is not fully known.  Chaudhuri et al recently conducted a meta-analysis, published in Critical Care Medicine this month, which reviewed the literature on this. 

Bottom Line: Yes, S:F ratios correlate well with P:F ratios, especially when the SpO2 is less than 97%, but you can't just substitute the S:F for P:F, you have to use one of the accepted formulas.  See additional info on the website for the actual formula to apply and how a given S:F translates to P:F.

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Title: Necrotizing Fasciitis on Ultrasound

Category: Ultrasound

Keywords: soft tissue; point of care ultrasound (PubMed Search)

Posted: 4/20/2026 by Alexis Salerno Rubeling, MD
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Sonographic findings suggestive of necrotizing fasciitis include: 

  • Thickening of the deep fascia 
  • Diffuse thickening of the overlying fatty tissue 
  • At least a 4 mm thick fluid layer along the deep fascia 
  • Dirty Shadow if gas is present

Remember the mnemonic: STAFF (subcutaneous thickening, air, and fascial fluid) 

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Title: Hidden in Plain Sight: Incidentally Detected Atrial Fibrillation on Continuous ECG Monitoring

Category: Cardiology

Keywords: Atrial Fibrillation, Incidental Finding, ECG Monitoring, Anticoagulation (PubMed Search)

Posted: 4/19/2026 by Lena Carleton, MD (Updated: 4/20/2026)
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Bottom line: Routine screening for atrial fibrillation (AF) is not recommended in the emergency department (ED). However, AF is often detected incidentally on continuous ECG monitoring. When identified, clinicians should inform the patient and consider anticoagulation if indicated.

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Title: Obesity, trauma and ARDS

Category: Trauma

Keywords: obesity, trauma, mortality, organ failure, sepsis, ARDS (PubMed Search)

Posted: 4/4/2026 by Robert Flint, MD (Updated: 4/18/2026)
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This German retrospective review of 1500 level one trauma center patients (ICU level or ISS over 9) found obesity was an independent predictor of ARDS, multisystem organ failure, and  sepsis but not pneumonia or mortality.

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Multiple past studies have shown that Black and female patients tend to be prescribed fewer opioids than White and male patients. This study looked at the rates of opioid usage post RSI.

They found that while Black patients received opioids at a higher rate, they were given lower doses than white patients. Older patients were less likely to receive opioids post RSI than younger patients.  They did not find a difference in rates of opioid usage between genders, but female patients received lower doses of opioids overall.

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Title: What are the signs of traumatic pancreatitis in the pediatric patient?

Category: Pediatrics

Keywords: Abdominal trauma, CT, lipase (PubMed Search)

Posted: 4/15/2026 by Jenny Guyther, MD (Updated: 4/17/2026)
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Pancreatic injury in pediatric blunt abdominal trauma is rare. 

This study was a secondary analysis of the data collected by the Pediatric Emergency Care Applied Research Network (PECARN) in the Intra-abdominal Injury Study Group. Of the children who had blunt abdominal trauma, 6% had intraabdominal injuries and 1% had pancreatitis.  A patient was considered as having traumatic pancreatitis if they had 2 of the following: 1) upper abdominal tenderness, 2) serum lipase of amylase > 3 x the upper limit of normal or 3) imaging study positive for pancreatitis.

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Title: Can EMS safely decide which child requires a cervical collar?

Category: EMS

Keywords: MVC, c-spine injury, PECARN, rules (PubMed Search)

Posted: 4/15/2026 by Jenny Guyther, MD (Updated: 4/22/2026)
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Cervical spine injuries (CSI) are uncommon in children, but when present, they are often devastating.  However, the application of a cervical collar in children is not benign and adverse effects include neck pain and discomfort and the downward tunnel vision it may create at the hospital leading to unnecessary testing.  Recently, the PECARN group published a set of criteria to determine who requires imaging of the cervical spine in the emergency department.  A planned subset of this initial study was to collect the impressions of EMS as they pertained to the 9 criteria to determine if these criteria could safely be used by EMS.  The patients who were brought in by EMS with the potential for cervical spine injury, who were evaluated by the trauma team and/or had cervical imaging AND had electronic case reports filled out by EMS were included in the final analysis.  Only 57% of the patients possible could be included based on the number of electronic case reports that were filled out.

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Title: More Protein or More Water?: Albumin vs. Crystalloid in Septic Shock

Category: Critical Care

Keywords: albumin, sepsis, septic shock, crystalloid, resuscitation (PubMed Search)

Posted: 4/14/2026 by Zachary Wynne, MD
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Summary:

The recent ARISS (Albumin Resuscitation in Septic Shock) trial showed no difference in 90-day mortality or other secondary outcomes, similar to other trials comparing albumin and crystalloid. Notably however, the trial did not meet its predetermined enrollment requirement of patients (in the setting of the COVID-19 pandemic) and had a large portion of its intervention group failing to meet goal serum albumin level. 

The Bottom Line:

There remains no evidence-based mortality benefit of albumin over crystalloid in patients with septic shock that do not have additional indications for albumin (such as hepatorenal syndrome). Crystalloid resuscitation remains a staple of appropriate and cost-effective care in septic shock. Albumin can be considered on a case-by-case basis after standard crystalloid resuscitation in this clinical setting.

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Title: Can US be effectively used in the prehospital setting?

Category: EMS

Keywords: prehospital, EMS, ultrasound (PubMed Search)

Posted: 4/4/2026 by Robert Flint, MD (Updated: 4/12/2026)
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This German retrospective study compared the prehospital use of ultrasound by trained paramedics and compared their findings to in-hospital diagnosis and image results. The authors found: 

“Diagnostic accuracy, defined as the concordance between prehospital POCUS-based working diagnoses and final in-hospital diagnoses, was particularly strong for lung ultrasound (pneumothorax, pulmonary edema, pneumonia and pleural effusion; sensitivity 91.7%, specificity 100%) and eFAST (sensitivity 100%, specificity 96.5%), while for the abdominal ultrasound examinations, the specificity was 70% and sensitivity was 71.43%.”

This study sets the stage for future prospective work looking at prehospital US use by paramedics.

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What elements of the history are most helpful for diagnosing a concussion?

An estimated 1.1 million to 1.9 million pediatric concussions occur annually in the US.

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Title: Best Practices for the <12 month old's airway

Category: Pediatrics

Keywords: pediatrics, airway, intubation, infant, neonate (PubMed Search)

Posted: 4/10/2026 by Kathleen Stephanos, MD (Updated: 4/22/2026)
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BOTTOM LINE:

  • Use of VL and cuffed ETTs are appropriate for all ages
  • Hyperangulated blades, LMAs and scopes should be available for rescue
  • Apneic oxygenation is useful in neonates. 

A 2024 meta analysis from the European Society of Anaesthesiology and Intensive Care and British Journal of Anaesthesia worked to develop joint guidelines for best practices for intubation of neonates and infants. 

While this guide is focused primarily on anesthesia and operative care, several of the recommendations have practical application to the EM and ICU as well. 

They focused on general guidance including ensuring appropriate anesthesia and analgesia during intubation. But also discussed that videolaryngoscopy with standard blades is the most appropriate first line for all intubations in this age group. It allows for appropriate visualization either directly or by video and for learners allows instructors to observe as well. 

When there are difficulties with intubation, hyperangulated blades have very high success rates, but LMA and video assisted intubation with a fiberoptic scope are also appropriate next steps for securing an airway. 

When intubating, uncuffed endotracheal tubes are acceptable in all infants though cuffed are also safe in infants over 3kg in weight.

Finally, while apneic oxygenation is regularly used in adults, it is also recommended in the neonatal period to avoid hypoxia.

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Title: Tenecteplase Strikes Out for CRAO

Category: Pharmacology & Therapeutics

Keywords: central retinal artery occlusion, tenecteplase, thrombolytic (PubMed Search)

Posted: 4/8/2026 by Alicia Pycraft (Updated: 4/9/2026)
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TenCRAOS was a phase 3 randomized, multi-center, double blind, double dummy, placebo-controlled trial in 78 patients that showed no significant difference in visual outcomes at 30 days for IV tenecteplase 0.25 mg/kg compared to aspirin 300 mg alone within 4.5 hours of central retinal artery occlusion (CRAO) symptom onset. Tenecteplase was associated with more serious adverse events, one of which was a fatal intracerebral hemorrhage.  

Bottom line: Although tenecteplase has theoretical advantages in CRAO, the results of this trial do not support routine use.

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Title: Gender affects trauma triage and care

Category: Trauma

Keywords: trauma, treatment disparity, gender (PubMed Search)

Posted: 4/4/2026 by Robert Flint, MD (Updated: 4/8/2026)
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This systematic literature review looking at gender differences in trauma care reveals:

  1. Women were older with more low-energy trauma than men. 
  2. Women were more likely to suffer from pelvic and spinal cord injuries. 
  3. Women were more likely to be under-triaged and under-treated.
  4. Sex/gender-based differences in mortality were inconsistent across studies. 
  5. Adjusted mortality appeared similar between women and men

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In a large, randomized trial conducted in 42 ICUs in France, high-flow oxygen did not reduce 28-day all-cause mortality in adult patients with acute hypoxemic respiratory failure when compared to standard oxygen support.

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Title: Geriatric learning objectives for prehospital providers

Category: Geriatrics

Keywords: prehospital, geriatric, education (PubMed Search)

Posted: 4/4/2026 by Robert Flint, MD (Updated: 4/5/2026)
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A  modified 2 round Delphi study was used to create 57 learning objectives in geriatric care for European prehospital providers.  Based on in-hospital learning objectives and literature, these experts came up with what appears to be a very reasonable and helpful list of education objectives for pre-hospital providers that could easily apply to emergency medicine learners as a whole. Here is their table:

https://link.springer.com/article/10.1186/s13049-026-01550-3/tables/3

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Title: Older patient splenic injury outcomes

Category: Trauma

Keywords: splenic injury, geriatrics, mortality (PubMed Search)

Posted: 4/4/2026 by Robert Flint, MD (Updated: 4/22/2026)
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In this retrospective cohort study looking at splenic injury management and outcomes in the UK, patients over age 65 had much higher mortality and were more often managed conservatively (vs splenectomy or embolization) despite having a lower splenic injury grade and lower overall injury severity score compared to those under 65. Many factors are possible here including frailty, reluctance to intervene in older patients, and lower mechanism of injury bias away from evaluation and management.

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Title: Rigid or soft-it may not matter

Category: Trauma

Keywords: Cervical immobilization, collar rigid, soft (PubMed Search)

Posted: 4/2/2026 by Robert Flint, MD (Updated: 4/22/2026)
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Looking at trauma patients evaluated at a major trauma center before and after EMS switched from semi-rigid to soft cervical collars for immobilization found no difference in adverse outcomes.  Add this to the mounting evidence that our current practice of spinal immobilization may not offer any benefit.

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Title: Marijuana Edibles: A Dangerous Treat

Category: Toxicology

Keywords: Edibles, Marijuana, Cannabis (PubMed Search)

Posted: 4/1/2026 by Kathy Prybys, MD
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Bottom LineEdible marijuana products have high potential for overdose, particularly in children, as they are commonly mistaken for appealing food or candy, have had exponential growth in availability and ease of access in homes, can be present in very large doses due to lack standardization and quality control, and users often have confusion regarding dosing due to its long and erratic absorption and time to peak effect which may lead to redosing.

Regulation of Cannabis-Infused Edibles - Network for Public Health Law

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The 2026 Acute Pulmonary Embolism Guidelines recommend a new approach to risk stratification of patients with acute PE, including measurement of at least one cardiac biomarker and serum lactate, evaluation of RV size and function with CTA or echo (preferred when feasible), and multidisciplinary PERT assessment for all patients with acute PE and elevated clinical severity scores to assist with further risk stratification.

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Title: SIPE - A Review

Category: Critical Care

Keywords: immersion, SIPE, swimmer, swimming (PubMed Search)

Posted: 3/30/2026 by TJ Gregory, MD
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Bottom Line: Swimming-Induced Pulmonary Edema (SIPE) AKA Immersion Pulmonary Edema is a rare, though life-threatening pathology associated with water-based activities, especially among athletes or military personnel. Caused by physiologic effects of immersion, not from aspiration/ingestion. Consider in any patient with respiratory distress or chest discomfort onset during water activities such as swimming, diving, etc. Diagnose with physical exam and POCUS. Manage supportively, potentially including positive pressure ventilation. Screen for alternative diagnoses.

See the link for more thorough review of assessment diagnostics, pathophysiology, pharmacological options, risk factors, and long-term considerations.

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