A common question is how much should we expect the blood glucose concentration to increase after dextrose 50% (D50) administration. Fortunately, there is an answer from 3 studies.
- Balentine JR, Gaeta TJ, Kessler D, Bagiella E, Lee T. Effect of 50 milliliters of 50% dextrose in water administration on the blood sugar of euglycemic volunteers. Acad Emerg Med. 1998;5(7):691-694. doi:10.1111/j.1553-2712.1998.tb02487.x PMID 9678393
- Population: Healthy volunteers in the ED
- Intervention: 25 gm (1 ampule of D50)
- Result: Mean increase of 162 mg/dL at 5 min. Glucose concentrations returned to baseline by 30 minutes.
- Murthy MS, Duby JJ, Parker PL, Durbin-Johnson BP, Roach DM, Louie EL. Blood glucose response to rescue dextrose in hypoglycemic, critically ill patients receiving an insulin infusion. Ann Pharmacother. 2015;49(8):892-896. doi:10.1177/1060028015585574. PMID 25986006
- Population: Critically ill patients experiencing hypoglycemia while on insulin infusions
- Intervention: D50
- Result: Median increase of 4 mg/dL per gm of D50 administered
- Adler PM. Serum glucose changes after administration of 50% dextrose solution: pre- and in-hospital calculations. Am J Emerg Med. 1986;4(6):504-506. doi:10.1016/S0735-6757(86)80004-3. PMID 3778594
- Population: ED patients with altered mental status (23 with diabetes, 28 without diabetes)
- Intervention: 25 gm (50 mL of D50)
- Result: Mean increase of 166 mg/dL
Take Home Points
- Glucose concentrations increase 4-6 mg/dL per gm of dextrose administered
- 50 mL of D50 = 25 gm = expected 100-150 mg/dL glucose rise
- D50 rescue glucose is short-lived (30 minutes)
- If the blood glucose does not respond as anticipated, investigate further (e.g., IV decannulation)
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What is the correct antidote for a patient who is poisoned with the pictured substance?
- Digoxin Specific Fab
- Hydroxocobalamin/Sodium Thiosulfate
(photo used with permission courtesy of Maureen Dallhoff, MD)
Which of the substances below causes crystalluria with hexagonal crystals that shimmer on macroscopic urine examination?
- Ethylene glycol
Urine drug tests are commonly sent for patients in the emergency department, however care should be taken when interpreting the results of these tests given their limitations. The American College of Medical Toxicology published a position statement on the interpretation of urine opiate and opioid tests . In this publication, they outline many of the limitations of opioid urine drug tests and explain why they exist.
- Though often used interchangeably, the terms opiate and opioid are not the same. ‘Opioid’ is the broad category name while ‘opiate’ simply refers to the naturally occurring opioids. The term ‘opioid’ encompasses opiates (e.g., morphine, codeine, opium), semi-synthetic agents (eg, heroin, hydrocodone, hydromorphone, oxycodone), and synthetic agents (eg, methadone, fentanyl, tramadol). Notice the name of the urine drug test next time you order one, it is likely specific for opiates (not opioids). This is because many tests are designed to identify morphine, though they will also detect codeine and heroin as they are both ultimately metabolized to morphine.
- The standard urine drug tests do not specifically look for oxycodone, hydrocodone, etc. However, they can trigger a positive result due to their structural similarities, but not in every case. Therefore, a negative result doesn’t rule out use of these common drugs.
- Similarly, synthetic opioids will not reliably cross-react with the opiate urine drug test as they are quite structurally dissimilar. In order to detect some of these agents, a test specific for the compound in question should be used.
- As there are numerous different manufacturers of urine drug tests, hospitals may not utilize the same tests. In order to further understand the methods and cross-reactivity of a hospital’s specific urine drug test, the hospital’s laboratory should be contacted to request the package insert. Below is an example of the cross reactivity between various opioids with a opiate urine drug test .
|Cross-reactivity of Various Opioids with Morphine Urine Drug Test |
|Compound||Equivalent to 300 ng/mL Morphine (ng/mL)||Cross-reactivity (%)|
- The term ‘opioid’ is the broad class of substances, while ‘opiate’ refers to the naturally occurring opioids (e.g., morphine, codeine)
- Many urine drug tests are designed to identify morphine and will also detect codeine and heroin, as they are ultimately metabolized to morphine
- Due to structural similarity, some semi-synthetic opioids may cross-react but fully synthetic opioids are unlikely to cross-react
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Acute agitation in the emergency department is a common issue that frequently requires the use of chemical sedation to preserve safety for patients and healthcare workers. A commonly employed treatment regimen is the combination of haloperidol 5 mg + lorazepam 2 mg + diphenhydramine 50 mg (B-52). Diphenhydramine is included in this treatment regimen primarily to prevent extrapyramidal symptoms [1,2]. However, the incidence of extrapyramidal symptoms (EPS) with haloperidol is quite low when treating agitation in the emergency department (ED) [3,4]. Therefore, the excessive and prolonged sedation from adding prophylactic diphenhydramine may outweigh the intended benefit and should be reserved for treatment of EPS if symptoms occur.
Jeffers et al. conducted a multicenter, retrospective, cohort study which compared the efficacy and safety of haloperidol, lorazepam, and diphenhydramine (B-52) (n=200) vs. haloperidol and lorazepam (52) (n=200) in treating patients >18 years old with acute agitation in the ED . Their primary outcome was the administration of additional agitation medication(s) within 2 hours.
|Outcomes||52 (n=200)||B52 (n=200)||p-Value|
|Administration of additional sedative within 2 h, n (%)||40 (20)||28 (14)||0.11|
|Median ED LOS (hours)||13.8||17||0.03|
|Use of restraints, n (%)||53 (26.5)||86 (43)||0.001|
|Hypotension, n (%)||7 (3.5)||32 (16)||<0.001|
|Administration of anticholinergic within 2 days, n (%)||15 (7.5%)||6 (3%)||0.04|
|Itching/allergies, n (%)||1 (0.5)||1 (0.5)||1.00|
|Home benztropine, n (%)||2 (1)||4 (2)||0.41|
|Insomnia, n (%)||4 (2)||0 (0)||0.06|
|Unknown, n (%)||8 (4)||1 (0.5)||0.02|
Overall, the B-52 combination resulted in more oxygen desaturation, hypotension, physical restraint use, and longer length of stay. However, the conclusions from this study may be limited as it was a relatively small study and it used surrogate markers to assess clinical endpoints.
Further discussion regarding the onset and duration of IM medications for acute agitation may be found in this blog post.
- The risk of extrapyramidal symptoms following haloperidol for agitation in the ED is relatively low
- Diphenhydramine may not be necessary when using haloperidol + lorazepam to treat agitation in the ED
- ED length of stay is increased with the addition of diphenhydramine to haloperidol + lorazepam
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- Mokhtari A, Yip O, Alain J, Berthelot S. Prophylactic administration of diphenhydramine to reduce neuroleptic side effects in the acute care setting: a systematic review and meta-analysis. J Emerg Med. 2021 Feb;60(2):165–74. doi: 10.1016/j.jemermed.2020.09.031. PMID: 33131965.
- Vinson DR, Drotts DL. Diphenhydramine for the prevention of akathisia induced by prochlorperazine: a randomized, controlled trial. Ann Emerg Med. 2001 Feb;37(2):125–31. doi: 10.1067/mem.2001.113032. PMID: 11174228.
- Klein LR, Driver BE, Miner JR, Martel ML, Hessel M, Collins JD, et al. Intramuscular midazolam, olanzapine, ziprasidone, or haloperidol for treating acute agitation in the emergency department. Ann Emerg Med. 2018 Oct;72(4):374–85. doi: 10.1016/j.annemergmed.2018.04.027. PMID: 29885904.
- Schneider A, Mullinax S, Hall N, Acheson A, Oliveto AH, Wilson MP. Intramuscular medication for treatment of agitation in the emergency department: A systematic review of controlled trials. Am J Emerg Med. 2021 Aug;46:193–9. doi: 10.1016/j.ajem.2020.07.013. PMID: 33071100.
- Jeffers T, Darling B, Edwards C, Vadiei N. Efficacy of combination haloperidol, lorazepam, and diphenhydramine vs. Combination haloperidol and lorazepam in the treatment of acute agitation: a multicenter retrospective cohort study. J Emerg Med. 2022 Mar 11;S0736-4679(22)00057-9. doi: 10.1016/j.jemermed.2022.01.009. PMID: 35287982.
Which toxic exposure can present with the pictured rash along with hypertension and tachycardia mimicking pheochromocytoma?