Emergency Medical Minute

Author: Dylan Luyten, M.D. Educational Pearls Around 30% of patients in the ER receive CT imaging, and the sensitivity of CT imaging may be improved with IV contrast. However, contrast is often withheld for fear of contrast-induced nephropathy. A recent, single-center, retrospective cohort study compared the rates of nephropathy between contrast CT, non-contrast CT, and no CT control patients, and found no differences. This study confirms what many have believed to be true - that the dangers of modern contrast may be overstated. However, the results should be interpreted with caution, as this was a retrospective, single-center study. References: Hinson, Jeremiah S. et al.. Risk of Acute Kidney Injury After Intravenous Contrast Media Administration. Annals of Emergency Medicine , Volume 69 , Issue 5 , 577 - 586.e4

Author: Don Stader, M.D. and Rachael Duncan, PharmD BCPS BCCCP Educational Pearls Carfentanil is an opioid elephant tranquilizer that can be used recreationally. It is 1000 times stronger than fentanyl, and looks like a white powder. Healthcare workers must be cautious when carfentanil overdose is suspected, as the drug can be absorbed through caregivers' skin if it is present on the patient's clothes. Overdose may require large amounts of naloxone, and a drip may be started at a rate equivalent to the bolus dose that the patient responded to. For example, if the patient responded to a 10mg bolus dose of naloxone, he would then be started on a 10mg/hr naloxone drip. References: https://www.dea.gov/divisions/hq/2016/hq092216.shtml

Author: Gretchen Hinson, M.D. Educational Pearls High-Altitude Pulmonary Edema (HAPE) is caused when hypoxemia due to low ambient pO2 leads to breakdown and constriction of the pulmonary vasculature leading to edema. HAPE is very rare under 8000 ft, but common over 10000 ft (6%). Over 18,000 ft the incidence is very high (12-15%). Symptoms include dyspnea, cough, weakness and chest tightness. Signs include hypoxemia, crackles, wheezing, central cyanosis, tachypnea and tachycardia. Drugs that reduce pulmonary resistance have been shown to help, but increased oxygenation and descent are the best treatments. References: http://emedicine.medscape.com/article/300716-overview

Author: Jared Scott, M.D. Educational Pearls Boerhaave syndrome (aka effort rupture of the esophagus) accounts for 10% of esophageal ruptures and is usually caused by strain during vomiting episodes. It can also be caused by childbirth, seizure, or prolonged coughing or laughing. Food and water swallowed after the tear end up in the mediastinum, eventually causing infection. Therefore, Boerhaave syndrome is a surgical emergency. Best diagnostic techniques are CT or endoscopy. Mallory-Weiss syndrome may present similarly, however it is less serious since it involves only a small tear through the mucosa at the gastroesophageal junction. This can be managed on an outpatient basis with PPI's. References: https://radiopaedia.org/articles/boerhaave-syndrome

Author: Aaron Lessen, M.D. Educational Pearls 2 studies this past year looked at pediatric and adolescent patients following a concussion. They found people who returned to activity sooner did better than those who went on "brain rest". While patients should still follow up with their PCP following a concussion, it is ok for patients to return to physical activity as tolerated. References: Grool AM, Aglipay M, Momoli F, Meehan WP, Freedman SB, Yeates KO, Gravel J, Gagnon I, Boutis K, Meeuwisse W, Barrowman N, Ledoux A, Osmond MH, Zemek R, for the Pediatric Emergency Research Canada (PERC) Concussion Team. Association Between Early Participation in Physical Activity Following Acute Concussion and Persistent Postconcussive Symptoms in Children and Adolescents. JAMA. 2016;316(23):2504-2514. doi:10.1001/jama.2016.17396

Author: Sam Killian, M.D. Educational Pearls Andrew Jackson was the 7th president of the USA. He served 2 terms from 1829-1837. He had had many medical issues during his presidency. He was said to be chronically underweight with rotting teeth. Furthermore, he had chronic infections and lead poisoning from bullets lodged in his arm and chest. He suffered from smallpox that he contracted while in a British prison during the Revolutionary War. He died from "dropsy" (CHF). References: http://www.doctorzebra.com/prez/g07.htm

Author: Jared Scott, M.D. Educational Pearls BB gun eye injuries are most common in August and September. They most often happen to males aged 16-17 year old. Around 10% of the BB eye injuries lead to eye loss. Accidental firearm injury is common in children and is a common cause of mortality. One-third of homes with children have a firearm. Most accidental pediatric gun injuries happen to young, male children with guns owned by family members. It is important to educate gun owners about proper gun storage. References: Childhood Firearm Injuries in the United States Katherine A. Fowler, Linda L. Dahlberg, Tadesse Haileyesus, Carmen Gutierrez, Sarah Bacon. Pediatrics Jun 2017, e20163486; DOI: 10.1542/peds.2016-3486

Author: Nick Hatch, M.D. Educational Pearls CPR-induced consciousness is a phenomenon that occurs when someone who was previously unconscious and is undergoing CPR regains consciousness and makes purposeful movements. Studies have shown that this phenomenon is increasing, likely because of increased quality of CPR. Many people use a sedative such as ketamine to keep patients unconscious to reduce the psychologic trauma of CPR. 39% of people who survive CPR with good neurologic details remember the process of CPR . References: Joshua Pound, P. Richard Verbeek, and Sheldon Cheske. CPR Induced Consciousness During Out-of-Hospital Cardiac Arrest: A Case Report on an Emerging Phenomenon. 2017. Prehospital Emergency Care Vol. 21.

Author: Sam Killian, M.D. Educational Pearls Anaphylaxis is common in the ED. These patients are treated and then usually watched for 4-6 hours. Biphasic happens in patients that have a complete resolution of their anaphylaxis for at least an hour, but then have a recurrence that requires pharmacologic intervention. Most of the time this happens 3-6 hours later, but can happen more than 10 hours later. More commonly happens in patients that have a delayed presentation, a wide pulse pressure, need multiple doses of epi, require the use of a beta agonist, or are ages 6-9 years old. Educate patients about the possibility of Biphasic anaphylaxis before discharge. References: http://www.medscape.org/viewarticle/583328_7

Author: Dylan Luyten, M.D. Educational Pearls Rhogam is commonly used when an Rh negative woman has an Rh positive fetus. It is commonly used in the ER in the setting of a miscarriage. Rh(+) fetal blood can enter the Rh(-) maternal circulation, sensitizing the woman to the Rh antigen. During a subsequent pregnancy, if the fetus is Rh(+), the woman may mount an immune response to the fetus, lead to fetal demise. Rhogam is used to block this process. Use of Rhogam has reduced this complication from 16% of Rh(+) pregnancies in the 1960's to less than 1% today. Under 10 weeks, the amount of maternal-fetal blood exchange is very small, so the use of Rhogam in a 1st trimester miscarriage is unnecessary. It should be used in patients with a miscarriage after 12 weeks, or women undergoing a surgical D&C. Rhogam is expensive and in limited supply, so it is important to only use it when necessary. References: Hannafin, Blaine et al. Do Rh-negative women with first trimester spontaneous abortions need Rh immune globulin? 2006. The American Journal of Emergency Medicine, Volume 24 , Issue 4 , 487 - 489