Bio at MichelleLinMD.com
The diagnosis of occlusive myocardial infarction (OMI) presents a unique challenge when complicated by left bundle branch block (LBBB) on electrocardiogram interpretation. While clinicians historically relied on the original Sgarbossa criteria, the field has evolved to embrace the Modified Sgarbossa-Smith criteria, which offers enhanced sensitivity and specificity in OMI diagnosis.
The Modified Sgarbossa-Smith criteria maintain 2 components from the original framework while introducing a crucial refinement to the third criterion:
1. Concordant ST elevation ≥ 1 mm in ≥ 1 lead
2. Concordant ST depression ≥ 1 mm in ≥ 1 lead of V1-V3
3. Excessive discordant ST elevation defined by an ST/S ratio ≥ 25% in any lead
Example of third criterion; Consider the 2 ECG tracings displaying similar ST segment elevation: one featuring a deep S wave (left) and another with a relatively shallow S wave (right). When the ST/S ratio exceeds 25% – as demonstrated in the right tracing with its approximately 50% ratio – it strongly suggests the presence of OMI.
This proportional approach marks a departure from the original criterion, which simply designated ST elevation > 5 mm as diagnostic, regardless of QRS amplitude. The modified criterion`s incorporation of the ST/S ratio acknowledges that tall QRS voltages, commonly encountered in left ventricular hypertrophy, can result in proportional, non-pathologic ST elevation greater than 5 mm.
For an excellent 2025 review with stellar illustrations of commonly missed OMI ECG tracings, read “ECG Patterns of Occlusion Myocardial Infarction: A Narrative Review” published as open access in Annals of Emergency Medicine. Worth a download.
Link in bio (PMID 39818676): https://www.annemergmed.com/article/S0196-0644(24)01250-2/fulltext
#postitpearls #foamed #emergencymedicine #nursepractitioner #physicianassistant #emresident #postit #ecg #ekg #sgarbossa #sgarbossasmith #cardiology #omi #myocardialinfarction #lbbb
For how many days do you prescribe nitrofurantoin (macroBID) in uncomplicated UTI?
The Goldilocks principle 🐻 applies:
- ❌3 days is too short
- ❌7 days is unnecessarily too long
- 🌟 5 days is just right!
Do you know about WikiGuidelines? They are an international, not-for-project collaborative that generates evidence-based guidelines for infectious diseases. They are a little different from other guideline orgs because they only provide recommendations if there are high-quality studies available. They don’t require experts to come to a consensus and make a recommendation on low-evidence topics. They seem transparent and admit uncertainty if there is not enough evidence.
In 2024, they published guidelines on UTI, published in JAMA.
https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2825634
One thing that stood out to me was that there was no evidence that a 7-day course of macroBID was better than a 5-day course. In the era of antibiotic stewardship to minimize antibiotic resistance, 5 days is the ideal duration with 79-92% efficacy. On the other spectrum, 3 days (as the NICE guidelines still advocate for) is too short with only 61-70% efficacy.
#postitpearls #foamed #emergencymedicine #nursepractitioner #physicianassistant #emresident #postit #infectiousdisease #wikiguidelines #uti #nitrofurantoin #macrobid #antibioticstewardship #antibiotics
What`s in the near future? 🔮
An epinephrine nasal spray (brand name Neffy) was approved by the Food and Drug Administration in August 2024 for the management of anaphylaxis. This may ultimately replace the traditionally prescribed auto-injector epinephrine, such as EpiPen. The benefits of the spray include:
⏳ Longer shelf life (30 months vs 18 months)
🥵 Can withstand extreme heat for a few days (such as leaving in a hot car)
💉 Reduces needle phobia, potentially improving patient adherence to self-administering epinephrine
Notably, the nasal spray is currently only approved for patients >66 pounds (30 kg). Also if a second spray is needed, be sure that it is administered in the same nostril to “stack” the dose.
💵 What is the cost to the patient per the manufacturing site?
• With commercial insurance: $25 per twin-pack
• Without insurance, using digital pharmacy service (GoodRx): $199 per twin-pack
🔮 Keep a lookout for this new option in your local pharmacies.
Manufacturer site: https://ir.ars-pharma.com/news-releases/news-release-details/ars-pharmaceuticals-receives-fda-approval-neffyr-epinephrine/
#postitpearls #foamed #emergencymedicine #nursepractitioner #physicianassistant #emresident #postit #epi #epinephrine #epinephrineinjection #allergicreaction #anaphylaxis
Have you heard of the Modified Glasgow-Blatchford Bleeding Score (GBS) for upper gastrointestinal (GI) bleeding risk stratification? How is different from the traditional GBS?
Background: American and European society guidelines in gastroenterology both recommend using a GBS value of ≤1 to identify low-risk patients who may be safe to manage as an outpatient for their upper GI bleed. The GBS calculation incorporates the following objective biometric measurements and historical elements:
Objective measures:
• Blood urea nitrogen (BUN)
• Hemoglobin
• Systolic blood pressure
• Heart rate
History:
• Melena
• Syncope
• Liver disease history
• Cardiac failure history
Often in the ED, determining the presence of non-objective measures can be challenging. The modified GBS calculation incorporates only the 4 objective biometric measures.
How does this modified score compare to the traditional GBS?
Published in Annals of EM this month, a large 2024 multicenter retrospective of 990 hospitalized patients with upper GI bleeds found that a GBS of ≤1 (sensitivity 99%, NPV 89%) and modified GBS=0 (sensitivity 99%, NPV 84%) both had strong discriminatory power in identifying such low-risk patients. The composite outcome measure was the need for a therapeutic intervention within 7 days (blood transfusion, endoscopic, surgical, or interventional radiology hemostasis) and/or death within 30 days. Notably, portal hypertension was NOT an exclusion criteria.
TLDR:
1. With a GBS≤1 or modified GBS=0, the patient may be at low enough risk for outpatient management for upper GI bleed.
2. Use the modified and traditional GBS tools as an adjunct to supplement clinical judgment.
Caution: This study was a retrospective analysis conducted in French hospitals of patients admitted to the hospital. However, the authors noted that the higher acuity nature of these hospitalized patients may result in a spectrum bias, which underestimates the negative predictive power for risk stratification in the ED.
Ref:
Thiebaud PC et al. Assessment of Prognostic Scores for Emergency Department Patients With Upper Gastrointestinal Bleeding. Ann Emerg Med. #postitpearls #blatchford
We know how to treat alcohol withdrawals but do you know about first-line FDA approved options to decrease cravings and increase abstinence for patients with chronic alcohol use disorder? Besides concurrent psychosocial counseling, these have demonstrated benefit per 2023 JAMA meta-analysis and systematic review (PMID 37934220) by McPheeters et al. Amazing NNT stats. Can consider starting medication in the Emergency Department especially if you have an Addiction or Counseling team.
1. Acamprosate (666 mg po TID)
- GABA agonist and glutamate modulator
- NNT 11 to reduce any drinking
- Need to be sober before starting
- Contraindication: Severe renal impairment
- Decreases alcohol withdrawal symptoms of insomnia and cravings
2. Naltrexone (50 mg po daily or 380 mg IM monthly)
- Opioid antagonist
- For oral route: NNT 18 to decrease any drinking and NNT 11 to decrease heavy drinking
- Can start while intoxicated
- Contraindication: Acute hepatitis, liver failure, active opioid use
- Decreases cravings presumably by blocking reward pathway from endogenous opioids and endorphins
#postitpearls #foamed #emergencymedicine #nursepractitioner #physicianassistant #emresident #postit #toxicology #medication #alcohol #alcoholism #aud #naltrexone #acamprosate
Hot off the press! The PECARN cervical spine injury prediction rule for injured children is published. Much like the head CT rule in blunt trauma, there are HIGH RISK and INTERMEDIATE RISK FACTORS.
High Risk (12.7% cervical injury):
* Abnormal A, B, or C
* Focal neurological deficits
* Severe altered mental status (U=unresponsive on the AVPU scale)
Intermediate Risk (2.8% cervical injury):
* Neck pain or tenderness
* Substantial head injury
* Substantial torso injury
* Disability (Opens eyes only to Verbal or Painful stimuli per AVPU scale)
What is considered a "substantial" head or torso injury? It`s an injury needing inpatient observation or surgery. Examples:
* Skull fracture
* Pneumothorax
* Signs of solid organ injury
* Spinal fracture
* Pelvic fracture
If there is at least 1 high risk factor, consider a CT of the c-spine. If not, and there is at least 1 intermediate risk factor, consider an XR. And if none of the above, you are safe to clinically clear the neck.
See next image for the official PECARN cervical spine injury prediction rule (along with their blunt head CT rules for age <2 and ≥2 years old).
Looking forward to applying this evidence-based approach to pediatric trauma care!
Downloadable PDF of the c-spine graphic: https://pecarn.org/pecarn_news/clinical-decision-rule-cervical-spine/
#postitpearls #foamed #emergencymedicine #nursepractitioner #physicianassistant #emresident #postit #trauma #pediatric #PECARN #radiology #decisionrule #cervicalspine #pecarn
Does your patient have a very elevated anion gap (AG) in the blood test results? It’s almost always associated with metabolic acidosis… even if your pH is elevated. That just means you now have a mixed acid-base status.
The way to think of AG is that it is a formula assessing the difference between measured cations (Na) and measured anions (HCO3- and Cl-). A decrease in unmeasured cations (K, Mg, Ca) can theoretically cause a trace elevation in AG, but it’s almost always an increase in unmeasured anions.
CATMUDPILES 🐈 is a helpful mnemonic to recall the causes of AG metabolic acidosis:
C Carbon monoxide, congenital heart disease, cyanide
A Aminoglycosides
T Theophylline, toluene
M Methanol
U Uremia
D DKA (also alcoholic/starvation ketacidosis)
P Paracetamol, paraldehyde
I Iron, INH, inborn errors of metabolism
L Lactic acidosis
E Ethanol, ethylene glycol
S Salicylates
What are some rare exceptions when an elevated AG is NOT from metabolic acidosis?
* Hyperalbuminemia
* IgA myeloma
These are unmeasured anions.
Helpful read: https://acutecaretesting.org/en/articles/clinical-aspects-of-the-anion-gap
#postitpearls #foamed #emergencymedicine #nursepractitioner #physicianassistant #emresident #postit #endocrinology #acidbase #aniongap #mudpiles #catmudpiles
Shoulder dislocations post-reduction care isn’t just “wear a sling”. You want to avoid a re-dislocation and a frozen shoulder (adhesive capsulitis).
So for anterior dislocations (which are almost all the shoulder dislocations), provide concrete instructions like:
1. Imagine you are wearing a large billboard sign on your back. Keep your arms in front of it. This avoids hyperextension of the shoulder. A special no-no is combing 🪮 the back of one’s hair (hyperextension AND significant abduction).
2. Every day for a few minutes take your arm out of the sling and bend over to allow your arm to dangle with gravity. You can prop your other arm on a table edge. Rock your body to create pendulous, circular ↔️ 🔄 movements of your shoulder joint. Increase the swinging radius over time. BONUS: While there, range your elbow, wrist, and hand to avoid loss of muscle tone and flexibility.
#postitpearls #foamed #emergencymedicine #nursepractitioner #physicianassistant #emresident #postit #orthopedic #shoulderdislocation
Is calcium chloride part of your last resort “kitchen sink” of medications for patients presenting in undifferentiated cardiac arrest?
It used to be. Increasingly retrospective studies, RCTs, and systematic reviews suggest that it isn’t beneficial. In fact, it may cause HARM (less ROSC and higher mortality). One RCT was stopped early for ethical reasons because the intervention arm (calcium) significantly caused more harm.
Why is calcium bad? A theory is that it causes hypercontraction and a “stone heart”.
This does NOT apply to special cases of cardiac arrest such as hyperkalemia, hypocalcemia, or other conditions where calcium is of direct benefit.
Use calcium judiciously in undifferentiated cardiac arrest. This recommendation was supported in the 2023 International Liaison Committee on Resuscitation (ILCOR) consensus statement (open access). PMID 37937881
#postitpearls #foamed #emergencymedicine #nursepractitioner #physicianassistant #emresident #postit #ilcor #cardiacarrest #calcium #resuscitation #ROSC #pharmacist
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Professor and Digital Innovation Lab Director
Department of Emergency Medicine
University of California, San Francisco
@M_Lin