Emergency Medical Minute

Dr. Kiersten Williams discusses postpartum hemorrhage and its causes. She highlights the 4 T's: Tone (atony), Trauma, Tissue, and Thrombin. AV malformations are underdiagnosed and estimated blood loss is not accurate. Fibrinogen levels should be above 400 mg/dl. Oxytocin should not be administered via IV push dose. Tranexamic Acid can be given in the field. The podcast also covers arteriovenous malformations, push doses of medications, and the use of trans-examic acid and uterine artery embolization to control bleeding.

Contributor: Meghan Hurley MD Educational Pearls: What is a nerve block? A nerve block is the medical procedure of injecting anesthetic into the area around a nerve to block pain signals. They are typically done with ultrasound guidance. Are nerve blocks effective? Most of the information we have about nerve blocks is extrapolated from fascia iliaca blocks. This nerve block targets the fascia iliaca compartment, which contains the femoral, lateral femoral cutaneous, and obturator nerves. These blocks are commonly done for hip fractures to help stabilize the patient while awaiting surgical repair. The data for these types of injections is strong. They decrease pain, they decrease total morphine equivalents needed while a patient is in the hospital, they help mobilize patients earlier and start physical therapy earlier, and they help patients leave the hospital about a day earlier. What is an example of an agent that can be used? Bupivacaine. A long acting amide-type local anesthetic. It works best when paired with epinephrine which causes local vasoconstriction and allows the bupivaciaine to bathe the nerve for longer. It gives 5-15 hours of anesthesia (complete sensation loss), and up to 30 hours of analgesia (pain loss). What's an example of another block that can be done? An Erector Spinae Plane (ESP) block is performed in the paraspinal fascial plane in the back. This can be used for pain around the ribs and before a variety of medical procedures including a Nuss procedure, thoracotomies, percutaneous nephrolithotomies, ventral hernia repairs, and even lumbar fusions. What is one potential complication of a nerve block? Local Anesthetic Systemic Toxicity (LAST). There are three ways this can happen: 1) Using too much total anesthetic (Maximum dose of bupivacaine is 2.5 mg/kg). 2) Too much anesthetic is injected into a confined space which then gets absorbed into the venous system. 3) Injecting directly into the vasculature by mistake. What are the signs that this complication has occurred? Perioral tingling Stupor Coma Seizures What can that cause? Cardiovascular collapse How is that treated? Intralipid AKA Soybean Oil, or "lipid emulsion" should be given as a bolus followed by a drip. These patients need to be admitted. Bolus 1.5 ml/kg (lean body mass) intravenously over 1 min (max ~100 ml). Continuous infusion at 0.25 mL/kg/min. Max dosing in the first 30 minutes is around 100 ml/kg. Fun fact: Patients being treated for LAST with intralipid cannot undergo general anesthesia because the intralipid will impact the anesthesia drugs. References Long B, Chavez S, Gottlieb M, Montrief T, Brady WJ. Local anesthetic systemic toxicity: A narrative review for emergency clinicians. Am J Emerg Med. 2022 Sep;59:42-48. doi: 10.1016/j.ajem.2022.06.017. Epub 2022 Jun 13. PMID: 35777259. Carvalho Júnior LH, Temponi EF, Paganini VO, Costa LP, Soares LF, Gonçalves MB. Reducing the length of hospital stay after total knee arthroplasty: influence of femoral and sciatic nerve block. Rev Assoc Med Bras (1992). 2015 Jan-Feb;61(1):40-3. doi: 10.1590/1806-9282.61.01.040. Epub 2015 Jan 1. PMID: 25909207. Jain N, Kotulski C, Al-Hilli A, Yeung-Lai-Wah P, Pluta J, Heegeman D. Fascia Iliaca Block in Hip and Femur Fractures to Reduce Opioid Use. J Emerg Med. 2022 Jul;63(1):1-9. doi: 10.1016/j.jemermed.2022.04.018. Epub 2022 Aug 4. PMID: 35933265. Kot P, Rodriguez P, Granell M, Cano B, Rovira L, Morales J, Broseta A, Andrés J. The erector spinae plane block: a narrative review. Korean J Anesthesiol. 2019 Jun;72(3):209-220. doi: 10.4097/kja.d.19.00012. Epub 2019 Mar 19. PMID: 30886130; PMCID: PMC6547235. Lee SH, Sohn JT. Mechanisms underlying lipid emulsion resuscitation for drug toxicity: a narrative review. Korean J Anesthesiol. 2023 Jun;76(3):171-182. doi: 10.4097/kja.23031. Epub 2023 Jan 26. PMID: 36704816; PMCID: PMC10244607. Weinberg, Guy. LipidRescue™ Resuscitation. http://www.lipidrescue.org/ Summarized by Jeffrey Olson MS2 | Edited by Jorge Chalit, OMSII

Contributor: Jorge Chalit, OMS II Educational Pearls: Migraine pathophysiology Primarily mediated through the trigeminovascular system Serotonin, dopamine, and calcitonin gene-related peptide (CGRP) Trigeminovascular system is linked to the trigeminal nucleus caudalis, which relays pain to the hypothalamus and cerebral cortex One effective treatment for acute migraines is -triptan medications 5-HT1D/1B agonists such as sumatriptan Often combined with NSAIDs and dopamine antagonists (as antiemetics) in migraine cocktails Diphenhydramine (Benadryl) was shown to be ineffective in a randomized controlled trial comparing it with placebo and a dopamine antagonist antiemetic. The -triptan medications carry significant risk for peripheral vasoconstriction and are therefore avoided in cardiovascular disease One serotonin agonist specifically approved for use in vascular disease Lasmiditan - 5-HT1F agonist Slightly different mechanism of action avoids peripheral vasoconstriction CGRP antagonists are also used in patients who are unresponsive to -triptans References 1. Friedman WB, Cabral L, Adewunmi V, et al. Diphenhydramine as adjuvant therapy for acute migraine. An ED-based randomized clinical trial. Ann Emerg Med. 2016;67(1):32-39.e3. doi:doi:10.1016/j.annemergmed.2015.07.495 2. Lasmiditan (Reyvow) and ubrogepant (Ubrelvy) for acute treatment of migraine. (2020). The Medical letter on drugs and therapeutics, 62(1593), 35–39. 3. Robbins MS. Diagnosis and Management of Headache: A Review. JAMA - J Am Med Assoc. 2021;325(18):1874-1885. doi:10.1001/jama.2021.1640 4. Vanderpluym JH, Halker Singh RB, Urtecho M, et al. Acute Treatments for Episodic Migraine in Adults: A Systematic Review and Meta-analysis. JAMA - J Am Med Assoc. 2021;325(23):2357-2369. doi:10.1001/jama.2021.7939 Summarized by Jorge Chalit, OMSII | Edited by Meg Joyce & Jorge Chalit, OMSII

Contributor: Aaron Lessen MD Educational Pearls: How is the severity of a stroke assessed? Strokes are assessed by the NIH Stroke Scale (NIHSS), this scale has different tasks, such as asking the person to repeat words, move their arms, or follow simple instructions. The maximum score is 42 but any score over 21 is considered severe. What would qualify as a minor storke? NIH This could be achieved with minor symptoms such as numbness Should patients with minor strokes be given thrombolytics? A new study in JAMA published in June of 2023 sought to answer this question. This study compares the effectiveness of dual antiplatelet therapy (DAPT) with intravenous thrombolysis in patients with minor non-disabling acute ischemic stroke. The research involved 760 participants in China, and the primary measure was an excellent functional outcome at 90 days. The results showed that DAPT was non-inferior to intravenous alteplase, with 93.8% of patients in the DAPT group and 91.4% in the alteplase group achieving an excellent functional outcome. The study suggests that DAPT could be a viable alternative to intravenous thrombolysis for patients with minor non-disabling strokes within 4.5 hours of symptom onset. Additionally, the incidence of symptomatic intracerebral hemorrhage was low in both groups. References 1. Chen HS, Cui Y, Zhou ZH, Zhang H, Wang LX, Wang WZ, Shen LY, Guo LY, Wang EQ, Wang RX, Han J, Dong YL, Li J, Lin YZ, Yang QC, Zhang L, Li JY, Wang J, Xia L, Ma GB, Lu J, Jiang CH, Huang SM, Wan LS, Piao XY, Li Z, Li YS, Yang KH, Wang DL, Nguyen TN; ARAMIS Investigators. Dual Antiplatelet Therapy vs Alteplase for Patients With Minor Nondisabling Acute Ischemic Stroke: The ARAMIS Randomized Clinical Trial. JAMA. 2023 Jun 27;329(24):2135-2144. doi: 10.1001/jama.2023.7827. PMID: 37367978; PMCID: PMC10300686. Summarized by Jeffrey Olson, MS2 | Edited by Meg Joyce & Jorge Chalit, OMSII

Contributor: Nick Tsipis MD Educational Pearls: The review article assessed 16.3 million patients across six states to identify those at high-risk for critical revisit Criteria for critical revisit was ICU admission or death within three days of discharge from the ED Critical revisits are extremely rare 0.1% of patients have a critical revisit after discharge 0.00001% die after revisit Of the patients that do experience critical revisits, the two major risk factors are Asthma - relative risk 2.24 Chronic medical conditions - incidence rate ratio 11.03 Of the top ten diagnoses that lead to critical revisits, 5 are respiratory Others include cellulitis, seizures, gastrointestinal disease, appendectomy, and sickle cell crisis. References 1. Cavallaro SC, Michelson KA, D'Ambrosi G, Monuteaux MC, Li J. Critical Revisits Among Children After Emergency Department Discharge. Ann Emerg Med. 2023;82(5):575-582. doi:10.1016/j.annemergmed.2023.06.006 Summarized by Jorge Chalit, OMSII | Edited by Meg Joyce & Jorge Chalit, OMSII

Contributor: Meghan Hurley MD Educational Pearls: Pearls about labor: Labor is split into 3 stages. Stage 1 starts when the first persistent contractions are felt and goes up until the cervix is fully dilated and the mother starts pushing. Stage 1 is split into two phases: the latent phase (cervix is dilated from 0-4 cm), and the active phase (cervix dilates from 4-10 cm). The latent phase can take between 6 and 12 hours with contractions happening every 5 to 15 minutes. The active phase usually lasts 4-8 hours with contractions occurring as close as every 3 minutes. Stage 2 is the birth itself, lasting between 20 minutes and 2 hours. Stage 3 is the delivery of the placenta and typically takes 30 minutes. 37 weeks gestational age is the cutoff for preterm. Placenta previa: Condition when the placenta overlies the cervix. Classically presents as painless vaginal bleeding in the 3rd trimester. If suspected placenta previa, avoid a speculum exam. Placenta previa can be confirmed on ultrasound. If the baby is crowning in the ER then the baby should be delivered in the ER. The ideal presentation on crowning is head first (Vertex), specifically 'left occiput anterior'. In this position, the baby is head first and the head is facing towards the gurney at a slight angle. If the baby is coming out in a breech position then the provider should "elevate the presenting part" by maintaining pressure on the baby as the mother is wheeled to the OR for an emergency C-section. If a vertex-presenting baby is being delivered vaginally, after the head has been delivered an event called 'restitution' must occur to align the baby's shoulders properly. During this event, the baby goes from facing down towards the gurney to facing sideways. After restitution, the anterior shoulder should be delivered, followed by the posterior. After complete delivery, the cord should be clamped (after a 1-3 minute delay), with something sterile. Gentle downward traction on the cord helps to deliver the placenta. You can place pressure above the pubic bone to prevent the uterus from involuting during this process. This is not the same as a fundal massage which happens after the delivery of the placenta to help the uterus clamp down and prevent postpartum hemorrhage. References Hutchison J, Mahdy H, Hutchison J. Stages of Labor. 2023 Jan 30. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan–. PMID: 31335010. Lavery JP. Placenta previa. Clin Obstet Gynecol. 1990 Sep;33(3):414-21. doi: 10.1097/00003081-199009000-00005. PMID: 2225572. Qian Y, Ying X, Wang P, Lu Z, Hua Y. Early versus delayed umbilical cord clamping on maternal and neonatal outcomes. Arch Gynecol Obstet. 2019 Sep;300(3):531-543. doi: 10.1007/s00404-019-05215-8. Epub 2019 Jun 15. PMID: 31203386; PMCID: PMC6694086. Summarized by Jeffrey Olson MS2 | Edited by Meg Joyce & Jorge Chalit, OMSII

Contributor: Dr. Taylor Lynch Educational Pearls: Time of arrival until intubation was 26 minutes but nobody tried anterior neck access like a cricothyrotomy until his dad arrived Traditional ACLS protocol is not enough for anaphylactic respiratory arrest Circulating O2 from compressions alone is not enough to sustain the brain Patients need a definitive airway and endotracheal tube is the best method BVM ventilation is not enough to get patients the oxygen they need Time to anoxic brain injury during a respiratory arrest is 4 minutes Definition of anaphylactic shock: Acute laryngeal involvement with bronchospasms after known exposure to an allergen Do not need to have skin symptoms like the classic wheal and flare Must also have either hypotension (from vasodilation or end-organ hypoperfusion) or severe GI symptoms (crampy abdominal pain or repetitive vomiting) Treatment of anaphylactic shock: Push-dose IV epinephrine is better than IM epinephrine because IM epinephrine takes 4 minutes to circulate and get to the lungs Ketamine has broncho-dilating properties so it can be used as an induction agent for intubation Albuterol and ipratropium as continuous bronchodilators Magnesium and IV steroids AMAX4 acronym Adrenaline, Muscle relaxant, Airway, Xtra (bronchodilators, ventilation, vasopressors, and consideration of pneumothorax), 4 minutes to anoxic brain injury References Commins SP. Outpatient Emergencies: Anaphylaxis. Med Clin North Am. 2017;101(3):521-536. doi:10.1016/j.mcna.2016.12.003 Ring J, Beyer K, Biedermann T, Bircher A, Duda D FJ et al. Guideline for acute therapy and management of anaphylaxis. S2 guideline of DGAKI, AeDA, GPA, DAAU, BVKJ, ÖGAI, SGAI, DGAI, DGP, DGPM, AGATE and DAAB. Allergo J Int. 2014;23(23):96-112. McKenzie B. AMAX4: Every Second Counts. Accessed Sunday, November 26, 2023. https://www.amax4.org/ Summarized by Jorge Chalit, OMSII | Edited by Meg Joyce & Jorge Chalit, OMSII

Contributor: Jared Scott MD Educational Pearls: Should we use opioids to treat low back and neck pain? The OPAL Trial, published in The Lancet, in June 2023, attempted to answer this very question. Objective: Investigate the efficacy and safety of a short course of opioid analgesic (oxycodone-naloxone) for acute low back pain and neck pain. Trial Design: Triple-blinded, placebo-controlled randomized trial, conducted in Emergency and Primary Care in Sydney, Australia, involving adults with 12 weeks or less of low back or neck pain. Participants: 347 recruited adults (174 in the opioid group, 173 in the placebo group) with at least moderate pain severity. Intervention: Participants were assigned to receive either an opioid or a placebo for up to 6 weeks. Primary Outcome: Pain severity at 6 weeks measured with the pain severity subscale of the Brief Pain Inventory (10-point scale). Results: No significant difference in pain severity at 6 weeks between the opioid group (mean score 2.78) and placebo group (mean score 2.25). Adverse events were reported by 35% in the opioid group and 30% in the placebo group, with more opioid-related adverse events in the opioid group (e.g., constipation). Conclusion: Opioids should not be recommended for acute non-specific low back pain or neck pain, as there was no significant difference in pain severity compared with the placebo. The study calls for a change in the frequent use of opioids for these conditions. Pharmacy Pearl: Why was naloxone mixed with oxycodone? Naloxone is an opioid receptor antagonist, meaning it can block the effects of opioids. When combined with oxycodone, naloxone's presence discourages certain forms of opioid misuse. Additionally, naloxone can bind to opioid receptors in the gut and improve symptoms of Opioid Induced Constipation (OIC). This is the same idea behind Suboxone (buprenorphine/naloxone). References Jones CMP, Day RO, Koes BW, Latimer J, Maher CG, McLachlan AJ, Billot L, Shan S, Lin CC; OPAL Investigators Coordinators. Opioid analgesia for acute low back pain and neck pain (the OPAL trial): a randomised placebo-controlled trial. Lancet. 2023 Jul 22;402(10398):304-312. doi: 10.1016/S0140-6736(23)00404-X. Epub 2023 Jun 28. Erratum in: Lancet. 2023 Aug 19;402(10402):612. PMID: 37392748. Camilleri M, Lembo A, Katzka DA. Opioids in Gastroenterology: Treating Adverse Effects and Creating Therapeutic Benefits. Clin Gastroenterol Hepatol. 2017 Sep;15(9):1338-1349. doi: 10.1016/j.cgh.2017.05.014. Epub 2017 May 19. PMID: 28529168; PMCID: PMC5565678. Summarized by Jeffrey Olson MS2 | Edited by Jorge Chalit, OMSII

Contributor: Jared Scott MD Educational Pearls A recently published study assessed the burden of respiratory viruses in a longitudinal cohort of children from 0 to 2 years of age The children in the study received nasal swab PCR testing weekly to determine infectivity They were also monitored for symptoms via weekly text surveys The study differentiated between infection and illness by defining an acute respiratory illness (ARI) as fever ≥38°C or cough. The median infectivity rate was 9.4 viral infections per child per year The median illness rate was 3.3 ARIs per child per year The most common etiological viruses isolated from the nasal samples were rhinovirus and enterovirus Most infections were asymptomatic or mild References Teoh, Z., Conrey, S., McNeal, M., Burrell, A., Burke, R. M., Mattison, C., McMorrow, M., Payne, D. C., Morrow, A. L., & Staat, M. A. (2023). Burden of Respiratory Viruses in Children Less Than 2 Years Old in a Community-based Longitudinal US Birth Cohort. Clinical infectious diseases: an official publication of the Infectious Diseases Society of America, 77(6), 901–909. https://doi.org/10.1093/cid/ciad289 Summarized by Jorge Chalit, OMSII | Edited by Meg Joyce & Jorge Chalit, OMSII

Contributor: Travis Barlock MD Educational Pearls: Common sedatives used in the Emergency Department and a few pearls for each. Propofol Type: Non-barbiturate sedative hypnotic agonizing GABA receptors. Benefit: Quick on and quick off (duration of action is approximately 2-7 minutes), helpful for suspected neurologic injury so the patient can wake up and be re-evaluated. Also has the benefit of reducing intracranial pressure (ICP). Downsides: Hypotension, bradycardia, respiratory depression. What should you do if a patient is getting hypotensive on propofol? Do not stop the propofol. Start pressors. May have to reduce the propofol dose if delay in pressors. Dexmedetomidine (Precedex) Type: Alpha 2 agonist - causes central sedation Uses: Patients are more alert and responsive and therefore can be on BiPAP instead of being intubated. Does not cause respiratory depression. Downsides: Hypotension and Bradycardia. Caution in using this for head injuries, its side effects can mask the Cushing reflex and make it more difficult to spot acute elevations in ICP and uncal herniation. Ketamine Type: NMDA antagonist and dissociative anesthetic, among other mechanisms. Benefits: Quick Onset (but slower than propofol). Does not cause hypotension, but can even increase HR and BP (Thought to potentially cause hypotension if patient is catecholamine-depleted (ie. sepsis, delayed trauma)). Dosing ketamine can be challenging. Typically low doses (0.1-0.3mg/kg (max ~30mg)) can give good pain relief. Higher doses (for intubation/procedural sedation) are generally thought to have a higher risk of dissociation. Downsides: Emergence reactions which include hallucinations, vivid dreams, and agitation. Increased secretions. Benzos Type: GABA agonists. Benefits: Seizure, alcohol withdrawal, agitation due to toxic overdoses. Push doses are useful because doses can stack. Longer half-life than propofol. Downsides: Respiratory depression. Longer half-life can make neuro assessments difficult to complete. Etomidate MOA: Displaces endogenous GABA inhibitors. Useful as a one-time dose for quick procedures (cardioversion, intubation). Often drug of choice for intubation since it is thought to have no hemodynamic effects. Downsides; If used without paralytic - myoclonus. Though to have some adrenal suppression. Fentanyl Type: Opioid analgesic. Not traditional sedative. Benefits: There are many instances in emergency medicine in which sedation can be avoided by prioritizing proper analgesia. Fentanyl can even be used to maintain intubated patients without needing to keep them constantly sedated. Downsides: Respiratory depression. Patients may have tolerance. References Chawla N, Boateng A, Deshpande R. Procedural sedation in the ICU and emergency department. Curr Opin Anaesthesiol. 2017 Aug;30(4):507-512. doi: 10.1097/ACO.0000000000000487. PMID: 28562388. Keating GM. Dexmedetomidine: A Review of Its Use for Sedation in the Intensive Care Setting. Drugs. 2015 Jul;75(10):1119-30. doi: 10.1007/s40265-015-0419-5. PMID: 26063213. Lundström S, Twycross R, Mihalyo M, Wilcock A. Propofol. J Pain Symptom Manage. 2010 Sep;40(3):466-70. doi: 10.1016/j.jpainsymman.2010.07.001. PMID: 20816571. Matchett G, Gasanova I, Riccio CA, Nasir D, Sunna MC, Bravenec BJ, Azizad O, Farrell B, Minhajuddin A, Stewart JW, Liang LW, Moon TS, Fox PE, Ebeling CG, Smith MN, Trousdale D, Ogunnaike BO; EvK Clinical Trial Collaborators. Etomidate versus ketamine for emergency endotracheal intubation: a randomized clinical trial. Intensive Care Med. 2022 Jan;48(1):78-91. doi: 10.1007/s00134-021-06577-x. Epub 2021 Dec 14. PMID: 34904190. Mihaljević S, Pavlović M, Reiner K, Ćaćić M. Therapeutic Mechanisms of Ketamine. Psychiatr Danub. 2020 Autumn-Winter;32(3-4):325-333. doi: 10.24869/psyd.2020.325. PMID: 33370729. Nakauchi C, Miyata M, Kamino S, Funato Y, Manabe M, Kojima A, Kawai Y, Uchida H, Fujino M, Boda H. Dexmedetomidine versus fentanyl for sedation in extremely preterm infants. Pediatr Int. 2023 Jan-Dec;65(1):e15581. doi: 10.1111/ped.15581. PMID: 37428855. Summarized by Jeffrey Olson MS2 | Edited by Jorge Chalit, OMSII