Emergency Medical Minute

Author: Michael Hunt, MD Educational Pearls: Organophosphate "nerve agents" were developed in the 1930's These agents have cholinergic effects, which can be remembered by the mnemonic "SLUDGE" Salivation Lacrimation Urination Defecation GI cramping Emesis The "SLUDGE" toxidrome is mediated through the muscarinic acetylcholine receptors. Nerve agents also affect the nicotinic acetylcholine receptors, which leads to muscle paralysis Death in these cases is from respiratory collapse due to secretions (bronchorrhea) and diaphragmatic paralysis Treatment includes atropine to reduce secretions (often in incredibly high doses) and pralidoxime (2-PAM) to treat muscle paralysis Benzodiazepines may be necessary for seizures References https://www.osha.gov/SLTC/emergencypreparedness/guides/nerve.html Michael Eddleston Novel Clinical Toxicology and Pharmacology of Organophosphorus Insecticide Self-Poisoning. Annual Review of Pharmacology and Toxicology 2019 59:1, 341-360 Summarized by Will Dewispelaere, MS4 | Edited by Erik Verzemnieks, MD

Contributor: Dylan Luyten, MD Educational Pearls: Insulin related hypoglycemia can vary from a brief transient effect from short-acting forms (i.e. insulin lispro) to prolonged from long acting (i.e. insulin glargine), and will require different treatment and/or observation Of oral glycemic agents, sulfonylureas are a common culprit while metformin is rarely a cause Sulfonylureas also deserve attention because in pediatric patients, they can be lethal even with a single ingestion, but also can cause severe hypoglycemia in adults Hypoglycemia in non-diabetics usually occurs in the malnourished, or in those with liver or adrenal disease References Klein-Schwartz W, Stassinos GL, Isbister GK. Treatment of sulfonylurea and insulin overdose. Br J Clin Pharmacol. 2016;81(3):496–504. doi:10.1111/bcp.12822 Tourkmani AM, Alharbi TJ, Rsheed AMB, AlRasheed AN, AlBattal SM, Abdelhay O, Hassali MA, Alrasheedy AA, Al Harbi NG, Alqahtani A. Hypoglycemia in Type 2 Diabetes Mellitus patients: A review article. Diabetes Metab Syndr. 2018 Sep;12(5):791-794. doi: 10.1016/j.dsx.2018.04.004. Epub 2018 Apr 12. Summarized by Will Dewispelaere, MS4 | Edited by Erik Verzemnieks, MD

Contributor: Jared Scott, MD Educational Pearls: Superior vena cava (SVC) syndrome is caused by physical compression of the SVC and can present with facial swelling, upper extremity swelling, flushing, and parasthesias Common causes of SVC syndrome include lung cancer, lymphoma, and thymoma Keep SVC syndrome on the differential for all patients with facial or upper extremity swelling References The superior vena cava syndrome: clinical characteristics and evolving etiology. Rice TW, Rodriguez RM, Light RW. Medicine (Baltimore). 2006;85(1):37. Diagnosis and management of superior vena cava syndrome. Markman M. Cleve Clin J Med. 1999;66(1):59. Summarized by Will Dewispelaere, MS4 | Edited by Erik Verzemnieks, MD

Contributor: Don Stader, MD Educational Pearls: The classic migraine cocktail includes: Reglan (or other dopamine antagonist), Benadryl, Toradol, Decadron, and IV fluids. The most effective agent in the cocktail is a dopaminergic agent Routine IV fluids have not shown efficacy There is no evidence for pre-treatment of akathisia with diphenhydramine (Benadryl) Decadron reduces rebound headache Consider trigger point injections for those with migraine attributable to cervical neck pain. References Jones CW, Remboski LB, Freeze B, Braz VA, Gaughan JP, McLean SA..Intravenous Fluid for the Treatment of Emergency Department Patients With Migraine Headache: A Randomized Controlled Trial. Ann Emerg Med. 2019 Feb;73(2):150-156. doi: 10.1016/j.annemergmed.2018.09.004. Epub 2018 Oct 26. Friedman BW, Cabral L, Adewunmi V, et al. Diphenhydramine as Adjuvant Therapy for Acute Migraine: An Emergency Department-Based Randomized Clinical Trial. Ann Emerg Med. 2016;67(1):32–39.e3. doi:10.1016/j.annemergmed.2015.07.495 Summarized by Will Dewispelaere, MS4 | Edited by Erik Verzemnieks, MD

Contributor: Don Stader, MD Educational Pearls: The common causes of anion gap metabolic acidosis include (MUDPILES) Metformin, Methanol Uremia DKA Paraldehyde INH/Iron Lactate Ethylene Glycol Salicylate Metformin is a very common drug used to treat type 2 diabetes, however in the right setting, it can cause a profound lactic acidosis. There is a very high mortality rate. Treatment of metformin toxicity includes fluids, bicarb, and dialysis Most commonly, metformin toxicity is in the setting of kidney injury or overdose. Always consider acidosis in those with tachypnea! References Re-evaluation of a biguanide, metformin: mechanism of action and tolerability. Sirtori CR, Pasik C Pharmacol Res. 1994;30(3):187. Bicarbonate haemodialysis as a treatment of metformin overdose.Heaney D, Majid A, Junor B. Nephrol Dial Transplant. 1997;12(5):1046. Extracorporeal Treatment for Metformin Poisoning: Systematic Review and Recommendations From the Extracorporeal Treatments in Poisoning Workgroup.Calello DP, Liu KD, Wiegand TJ, Roberts DM, Lavergne V, Gosselin S, Hoffman RS, Nolin TD, Ghannoum M, Extracorporeal Treatments in Poisoning Workgroup Crit Care Med. 2015;43(8):1716. Metformin accumulation: lactic acidosis and high plasmatic metformin levels in a retrospective case series of 66 patients on chronic therapy.Vecchio S, Giampreti A, Petrolini VM, Lonati D, Protti A, Papa P, Rognoni C, Valli A, Rocchi L, Rolandi L, Manzo L, Locatelli CA Clin Toxicol (Phila). 2014;52(2):129. Summarized by Will Dewispelaere, MS4 | Edited by Erik Verzemnieks, MD

Contributor: Aaron Lessen, MD Educational Pearls: Hemophilia is characterized by bleeding (A /B) A is is 8, B (chrstmas, 9) Hemophilia refers to a group of bleeding disorders caused by a deficiency in a certain clotting factor. The two most common are hemophilia A (caused by a lack of factor VIII), and B (caused by a lack of factor 9) Most cases are inherited in an X-linked recessive manner. Therefore, males are the most commonly affected. However, spontaneous cases do occur in all sexes. People with hemophilia can present to the ED with a variety of bleeding complications including hemarthrosis, intracranial hemorrhage, and GI bleeds. Treatment is guided by the type of hemophilia and the degree of bleeding, with the most severe cases being treated with replacement of 100% of that person's deficient clotting factor. Timely treatment improves outcomes, so consider empiric therapy in those with known hemophilia References Hemophilia A in the third millennium.Franchini M, Mannucci PM Blood Rev. 2013 Jul;27(4):179-84. Epub 2013 Jun 28. Rheumatic manifestations of hematologic disorders.Aviña-Zubieta JA, Galindo-Rodriguez G, Lavalle C Curr Opin Rheumatol. 1998;10(1):86. The molecular genetics of hemophilia: blood clotting factors VIII and IX.Lawn RM Cell. 1985;42(2):405. Guidelines for the management of hemophilia.Srivastava A, Brewer AK, Mauser-Bunschoten EP, Key NS, Kitchen S, Llinas A, Ludlam CA, Mahlangu JN, Mulder K, Poon MC, Street A, Treatment Guidelines Working Group on Behalf of The World Federation Of Hemophilia Haemophilia. 2013 Jan;19(1):e1-47. Epub 2012 Jul 6. Summarized by Will Dewispelaere, MS4 | Edited by Erik Verzemnieks, MD

Contributor: Michael Hunt, MD Educational Pearls: Cirrhosis is the end stage of chronic structural damage to the liver. This is most commonly due to alcohol but other causes viral hepatitis and hepatotoxic drugs Cirrhotic patients are very prone to GI bleeding and infections, partially due to the role the liver plays in producing immune and clotting factors These patients can easily become "sick". Use the shock index (heart rate / systolic blood pressure) as a rapid assessment of hemodynamic status. >0.7 is worrisome, >1 should prompt resuscitation. Because cirrhotic patients are immunocompromised, do not rely on the presence of fever and peritonitis to diagnose spontaneous bacterial peritonitis (SBP), and have a low threshold to perform a diagnostic paracentesis Polymorphonuclear (PMN) count > 250 in the ascitic fluid suggests SBP With GI bleeding in cirrhotics, antibiotics have a mortality benefit, while PPIs and octreotide have limited benefit References Chinnock B, Hendey GW, Minnigan H, Butler J, Afarian H. Clinical impression and ascites appearance do not rule out bacterial peritonitis. J Emerg Med. 2013 May;44(5):903-9. doi: 10.1016/j.jemermed.2012.07.086. Epub 2013 Mar 7. Pericleous M, Sarnowski A, Moore A, Fijten R, Zaman M. The clinical management of abdominal ascites, spontaneous bacterial peritonitis and hepatorenal syndrome: a review of current guidelines and recommendations. Eur J Gastroenterol Hepatol. 2016 Mar;28(3):e10-8. doi: 10.1097/MEG.0000000000000548. Chavez-Tapia NC, Barrientos-Gutierrez T, Tellez-Avila F, Soares-Weiser K, Mendez-Sanchez N, Gluud C, Uribe M.Meta-analysis: antibiotic prophylaxis for cirrhotic patients with upper gastrointestinal bleeding - an updated Cochrane review. Aliment Pharmacol Ther. 2011 Sep;34(5):509-18. doi: 10.1111/j.1365-2036.2011.04746.x. Epub 2011 Jun 27. Summarized by Will Dewispelaere, MS4 | Edited by Erik Verzemnieks, MD

Contributor: Erik Verzemnieks, MD Educational Pearls: Knee dislocations are most common in high energy trauma, such as a motor vehicle accident The knee may appear grossly normal on initial inspection since dislocations can spontaneously reduce - Look for such findings as hemarthrosis, instability, or ecchymosis, as clues to an occult dislocation. Knee dislocations are often associated with damage to the popliteal artery that runs behind the knee. Assess for pulse deficit on exam. If you are concerned - use the ankle-brachial index (normal >0.9). If the ABI is abnormal, evaluate with CT angiogram and a vascular surgery consult. References Mills WJ, Barei DP, McNair P. The value of the ankle-brachial index for diagnosing arterial injury after knee dislocation: a prospective study. J Trauma. 2004 Jun;56(6):1261-5. Steele HL, Singh A. Vascular injury after occult knee dislocation presenting as compartment syndrome. J Emerg Med 2012; 42:271. Sillanpää PJ, Kannus P, Niemi ST, et al. Incidence of knee dislocation and concomitant vascular injury requiring surgery: a nationwide study. J Trauma Acute Care Surg 2014; 76:715. Summarized and written by myself

Contributor: Charleen Melton, PharmD Educational Pearls: Desmopressin (DDAVP) is an analogue of anti-diuretic hormone (ADH) that has been used for the treatment of intracranial hemorrhage. It works by increasing the release of Von Willebrand factor, helping to stabilize clots. The use of DDAVP for intracranial hemorrhage in patients on antiplatelet agents (mainly Aspirin and Plavix) was recently reviewed In this retrospective review, they found an 88% decreased likelihood of hemorrhage expansion, in those who received DDAVP, compared to those who did not. Furthermore, they found no significant increase in adverse effects like hyponatremia or thrombosis However, no difference in mortality or neurological status was found DDAVP for intracranial hemorrhage in the setting of antiplatelet agents may be safe and reduce the expansion of intracranial bleeds but not change important patient outcomes References Feldman EA et al. Retrospective assessment of desmopressin effectiveness and safety in patients with antiplatelet-associated intracranial hemorrhage. Crit Care Med 2019 Sep 24; [e-pub] Summarized by Will Dewispelaere, MS4 | Edited by Erik Verzemnieks, MD

Contributor: Jared Scott, MD Educational Pearls: The ED is full of painful procedures. One of the most commonly dreaded procedures is nasal packing for epistaxis, as it is quite uncomfortable for the patient. A recent study compared TXA with compression, saline with compression, and traditional nasal packing for the treatment of epistaxis. Hemostasis was achieved in 91% with TXA and compression, 93% with nasal packing, and 71% with saline and compression. There was no statistically significant difference between the packing and TXA groups. Furthermore, there was no difference in rates of rebleeding between the TXA and packing groups. However, 15% of nasal packing patients demanded removal of the packing due to pain. Consider TXA (on gauze or atomized) for your next patient with epistaxis! References Akkan, Sedat et al.. Evaluating Effectiveness of Nasal Compression With Tranexamic Acid Compared With Simple Nasal Compression and Merocel Packing: A Randomized Controlled Trial. Annals of Emergency Medicine, Volume 74, Issue 1, 72 - 78 Summarized by Will Dewispelaere, MS4 | Edited by Erik Verzemnieks, MD