Emergency Medical Minute

Author: Sam Killian, M.D. Educational Pearls The availability of antiepileptic treatment has changed in the last 30 years. A recent study in JAMA followed 18,000 pts with epilepsy for 30 years to assess the effectiveness of looked at seizure control. The study found that although there have been new drugs introduced over the last 30 years, there has not been much of an improvement in seizure control. Side effect profiles and medicine compliance may have improved in this time period, but the main goal of reducing seizure frequency has not been reached. References: Chen Z, Brodie MJ, Liew D, Kwan P. Treatment Outcomes in Patients with Newly Diagnosed Epilepsy Treated With Established and New Antiepileptic DrugsA 30-Year Longitudinal Cohort Study. JAMA Neurol. Published online December 26, 2017. doi:10.1001/jamaneurol.2017.3949

Educational Pearls Truvada (Emtricitabine/tenofovir) is a combination nucleotide reverse transcriptase inhibitor that can be used as pre-exposure prophylaxis (PrEP) for HIV. It has been shown to dramatically reduce the risk of contracting HIV. It is used in high-risk patients, like the MSM community or those who are in a relationship with someone with HIV. Side effects include nausea, vomiting, headache, and liver damage. HIV testing should be performed every 3 months while taking it, since it is not meant to fight an actual infection. Since 2012, there have only been 3 confirmed cases of transmission while using Truvada. It costs between 50-60$ dollars per pill, but it is covered by most insurances, including Medicaid. Generic version has recently been FDA approved. References: https://www.cdc.gov/hiv/pdf/prep_gl_patient_factsheet_truvada_english.pdf

Author: Rachael Duncan, PharmD Educational Pearls A NEJM study report in July 2016 discussed a situation in New York during which 30 people became "zombie-like" after ingesting synthetic cannabinoids (aka "Spice). The ER managed to coordinate with the CDC to evaluate blood samples from 18 patients who were transported to the hospital. Of those who went to the ER, the mean age was 36.8, many of them were homeless, all of them were male. Mass spectrometry was used to confirm the presence of synthetic cannabinoid in their blood. Compared to normal THC, synthetic cannabinoids have a much lower EC50 and LD50. Spice intoxication presents in a variety of ways -patients may be hyperthermic, combative, delirious and/or seizing. Treatment is supportive, including fluids, cooling, electrolyte management, and sedatives. References: Adams, A. J., Banister, S. D., Irizarry, L., Trecki, J., Schwartz, M., & Gerona, R. (2017). "Zombie" Outbreak Caused by the Synthetic Cannabinoid AMB-FUBINACA in New York. New England Journal of Medicine, 376(3), 235-242. doi:10.1056/nejmoa1610300

Author: Sam Killian, M.D. Educational Pearls Traditionally, UTI diagnosis has been dependent on urine culture, urinalysis and clinical symptoms. But a recent study casts some doubt on the utility of urine cultures. A study in the Journal of Clinical Microbiology did urine cultures and E. coli PCR in 220 women with UTI symptoms and 86 women without UTI symptoms. In the symptomatic women, 67% had positive E. Coli PCR and 98% had a pathogenic bacteria in their urine culture. In the asymptomatic women, 10% had positive E. coli PCR and/or urine culture. Therefore, this study suggests that urine culture may be of limited utility, since symptoms alone seemed to predict bacteriuria. References: Burd EM, Kehl KS. A Critical Appraisal of the Role of the Clinical Microbiology Laboratory in the Diagnosis of Urinary Tract Infections. Journal of Clinical Microbiology. 2011;49(9 Supplement). doi:10.1128/jcm.00788-11.

Author: Michael Hunt, M.D. Educational Pearls Rhabdomyolysis is caused by the destruction of skeletal muscle that leads to the release of myoglobin, which causes renal failure. It presents with pain and weakness in the affected muscle, as well as dark urine. Diagnosis is made with creatinine kinase levels It can happen to extreme athletes after competition, but the most common presentation is in people who fall and are immobilized for long periods of time. Other causes include burns, crush injuries, viral infections (influenza), bacterial infections (Legionella), and medications (statins in adults, propofol in kids) Treatment is aggressive fluids References: Huerta-Alardín AL, Varon J, Marik PE. Bench-to-bedside review: Rhabdomyolysis – an overview for clinicians. Critical Care. 2005;9(2):158-169. doi:10.1186/cc2978.

Author: Sam Killian, M.D. Educational Pearls Transient global amnesia is a paroxysmal, transient memory issue. Remote and immediate memory is preserved, but new memories cannot be made. Patients will have a normal neurological exam and usually no other complaints. The episode will last less than 24 hours, but they usually resolve after 1-2 hours. This is relatively common. It happens in 5/100000 people, mostly men over 50. Recurrence is rare. There is no known cause, but it is associated with migraines and classically occurs after heavy physical exertion or emotional stress. Workup includes a full neuro exam, imaging for ongoing symptoms, and labs to rule out other causes. Patients can be sent home with reassurance after symptoms resolve. Instruct them to follow up with neurology. Patients with continuing symptoms should be admitted. References: Owen D, Paranandi B, Sivakumar R, Seevaratnam M. Classical diseases revisited: transient global amnesia. Postgraduate Medical Journal. 2007;83(978):236-239. doi:10.1136/pgmj.2006.052472.

Author: John Winkler, M.D. Educational Pearls Normally, the parathyroid is the master regulator of serum Ca levels. It secretes PTH, which stimulates calcium uptake from the bone and gut. Causes of hypercalcemia include: parathyroid tumor, lytic bone lesions (multiple myeloma), breast cancer, renal injury, and some lung cancers. Hypercalcemia can lead to poor bone quality and pathological fractures. It can also cause heart arrhythmias. It is important to order an ionized calcium to quantify the level of hypercalcemia, since calcium binds to albumin. Treatment for hypercalcemia includes fluids and loop diuretics. References: https://emedicine.medscape.com/article/766373-treatment

Author: Nick Hatch, M.D. Educational Pearls The Cincinnati Stroke Scale uses 3 measures to screen for ischemic stroke. The measures are: facial asymmetry, speech quality and arm drift. This scale is used commonly in EMS systems as a screening tool. Studies show that having one out of the 3 elements correlates with a 72% chance of having an ischemic stroke, while having all 3 of the elements correlates with an 85% chance. Overall the scale is highly sensitive but not very specific (92% and 48%, respectively, in one study). The measures focus on anterior circulation function, and often misses posterior circulation strokes. The Cincinnati Stroke Scale is good for EMS, but not necessarily for emergency physicians. References: http://onlinelibrary.wiley.com/store/10.1002/9781118783467.app5/asset/app5.pdf?v=1&t=jcf2yn71&s=3c2341ba472c1fcc88003dc0af7eac28691dd980

Author: Dave Rosenberg, M.D. Educational Pearls DKA commonly causes hyperkalemia, leading to peaked T-waves on ECG. However, DKA causes hypokalemia at the same time. In DKA, glucose cannot be taken into the cells. This signals the body to create and use acidic ketones for energy. This leads to acidosis. To compensate for increased acid, H ions are pumped into cells. To maintain electroneutrality, K is pumped out of the cell. At the kidney, K is lost in the urine. Overall, while serum K is high in DKA, total body K is low. The derangement in K can lead to life-threatening arrhythmias. Treatment for DKA can induce hypokalemia, as the K will shift back into the cells with insulin administration. Therefore, treatment for DKA needs to include K. References: http://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/diabetes-mellitus-and-disorders-of-carbohydrate-metabolism/diabetic-ketoacidosis-dka

Author: Dylan Luyten, M.D. Educational Pearls Cannabinoid Hyperemesis syndrome is a relatively new diagnosis that presents with vomiting and abdominal pain without a clear etiology in the setting of daily marijuana use. The pathophysiology is not well-understood well, but may involve cannabinoid receptors in the gut. Treatment is abstinence from marijuana, fluids, dextrose, and antiemetics (haldol, ondansetron, etc). Opioids should be avoided. Capsaicin cream on the abdomen may be helpful, as it can distract from the pain and vomiting. Milk can be used to reverse its effects. References: Galli JA, Sawaya RA, Friedenberg FK. Cannabinoid Hyperemesis Syndrome. Current drug abuse reviews. 2011;4(4):241-249.