Contributor: Aaron Lessen, MD

Educational Pearls:

How long do we need to watch patients with a presumed overdose who were treated with naloxone in the field?

• A 2025 study in the Annals of Emergency Medicine took a look at this question
• Methods
  • Prospective, multi-institutional cohort study
  • Included ED patients with suspected acute opioid overdose with biologic testing to confirm substances.
  • This paper performed a secondary analysis evaluating the risk of "delayed intubation," defined as intubation occurring >4 hours after ED arrival.
• Results
  • 1,591 patients with presumed opioid overdose were included.
  • Delayed intubation occurred in only 9 patients (0.6%).
  • 8 of the 9 cases had non-respiratory causes contributing to intubation.
  • Only 1 patient had respiratory-related deterioration, presenting with respiratory acidosis after receiving 6.4 mg naloxone prior to intubation.
• Key Takeaway
  • Delayed respiratory deterioration requiring intubation after 4 hours of ED monitoring is extremely rare, suggesting prolonged monitoring may not be necessary for most stabilized overdose patients.

How else can we mitigate risk?

• Give patients take-home naloxone at discharge and educate them on how to use it (See Episode 673: Leaving the ED with Naloxone).

When are naloxone drips necessary?

• If a patient requires repeated naloxone boluses, consider a drip
• To get the dose, take the total naloxone dose that restored adequate breathing and give two-thirds of that dose per hour
• Typically these patients are admitted to the ICU

References

1. McCabe DJ, Gibbs H, Pratt AA, Culbreth R, Sutphin AM, Abston S, Li S, Wax P, Brent J, Campleman S, Aldy K, Falise A, Manini AF; ToxIC Fentalog Study Group. Risk of Delayed Intubation After Presumed Opioid Overdose in the Emergency Department. Ann Emerg Med. 2025 Jun;85(6):498-504. doi: 10.1016/j.annemergmed.2025.01.022. Epub 2025 Mar 4. PMID: 40047773; PMCID: PMC12955731.

Summarized and edited by Jeffrey Olson MS4

Donate: https://emergencymedicalminute.org/donate/

Join our mailing list: http://eepurl.com/c9ouHf

Contributor: Travis Barlock, MD

Educational Pearls:

• D-dimer: fibrin degradation product used to evaluate for clot formation and breakdown
  • Threshold: <500ng/mL rules out venous thromboembolism in low risk patients
  • Elevated D-dimer indicates recent or ongoing intravascular coagulation and fibrinolysis
• YEARS score: algorithm to assess PE risk using three clinical criteria
  • Criteria: signs of DVT, hemoptysis, and PE as the most likely diagnosis
  • YEARS score of 0 with D-dimer <1000 ng/mL: PE can be ruled out
  • YEARS score of ≥1 with D-dimer <500 ng/mL: PE can be ruled out
  • A study found that YEARS score accurately predicted the presence or absence of PE in 80% of enrolled patients with 90% sensitivity and 65% specificity
• D-dimer may also help exclude aortic dissection: Aortic Dissection Detection Risk Score (ADD-RS)
  • When ADD-RS = 0 or 1 and D-dimer <500ng/mL: aortic dissection may be ruled out in low-risk patients
  • When ADD-RS >1, patients are considered high probability for aortic dissection and CT should be performed

References

1. Fayiad, H., Moussa, H., Nosair, Y. et al. Predictive accuracy of years score in diagnosis of pulmonary embolism. Egypt J Bronchol 18, 18 (2024). https://doi.org/10.1186/s43168-024-00269-y
2. Weitz JI, Fredenburgh JC, Eikelboom JW. A Test in Context: D-Dimer. J Am Coll Cardiol. 2017 Nov 7;70(19):2411-2420. doi: 10.1016/j.jacc.2017.09.024. PMID: 29096812.
3. Yichao Ma,Zhenjiang Ding,Yunong Zhao,Paijiao Zhang,Bo Du,Ye Shen,Junmei Hu,Luqi Zhu,Honghong Zhao,Chunrong Jin,Yuhong Wang,Lizhen Gao,Research progress on multi-marker detection technology for cardiovascular diseases (review), Journal of Electroanalytical Chemistry, 1008, (119969), (2026).

Summarized by Meg Joyce, MS2 | Edited by Meg Joyce & Jorge Chalit, OMS4

Donate: https://emergencymedicalminute.org/donate/

Contributor: Taylor Lynch MD
Educational Pearls:

• Melatonin is an endogenous hormone released primarily by the pineal gland
  • Also released by extrapineal regions in the retina, the GI tract, and some immune cells
• Peak secretion occurs at night and is suppressed during the day
  • Secretion and production decrease with age
  • Older patients experience the greatest improvement in sleep latency and sleep quality
• Mechanism of action in the suprachiasmatic nucleus of the hypothalamus
  • MT1 receptor
    • Reduces normal firing
  • MT2 receptor
    • Shifts the circadian rhythm
• FDA approved for insomnia
  • Decreases sleep latency by 7 minutes
  • Increases total sleep time by 8 minutes
• FDA approved for circadian sleep-wake disorders
  • Jet lag
    • Most effective in west-to-east travel
    • Best if crossing at least 5 time zones
  • Shift work
    • A study examined ED physicians and nurses with rotating shifts
    • Modest increase in deep sleep percentage
    • No difference in cognition or reaction time the day after taking melatonin
    • Nurses on rotating night shifts experienced increased total sleep time by 20 minutes
• Dosing
  • 0.5 - 3 mg is the most evidence-based dosing
  • Higher doses increase the risk of rebound grogginess but do not improve outcomes

References

1. Ahmad SB, Ali A, Bilal M, et al. Melatonin and Health: Insights of Melatonin Action, Biological Functions, and Associated Disorders. Cell Mol Neurobiol. 2023;43(6):2437-2458. doi:10.1007/s10571-023-01324-w
2. Herxheimer A, Petrie KJ. Melatonin for the prevention and treatment of jet lag. Cochrane Database Syst Rev. 2002;(2):CD001520. doi:10.1002/14651858.CD001520
3. Morgenthaler TI, Lee-Chiong T, Alessi C, Friedman L, Aurora RN, Boehlecke B, Brown T, Chesson AL Jr, Kapur V, Maganti R, Owens J, Pancer J, Swick TJ, Zak R; Standards of Practice Committee of the American Academy of Sleep Medicine. Practice parameters for the clinical evaluation and treatment of circadian rhythm sleep disorders. An American Academy of Sleep Medicine report. Sleep. 2007 Nov;30(11):1445-59. doi: 10.1093/sleep/30.11.1445. Erratum in: Sleep. 2008 Jul 1;31(7):table of contents. PMID: 18041479; PMCID: PMC2082098.
4. Thottakam BMVJ, Webster NR, Allen L, Columb MO, Galley HF. Melatonin Is a Feasible, Safe, and Acceptable Intervention in Doctors and Nurses Working Nightshifts: The MIDNIGHT Trial. Front Psychiatry. 2020;11:872. Published 2020 Aug 27. doi:10.3389/fpsyt.2020.00872

Summarized and edited by Jorge Chalit, OMS4

Donate: https://emergencymedicalminute.org/donate/

Join our mailing list: http://eepurl.com/c9ouHf