Infographic: Access Flow Rates

Infographic for IV flow rates

Notes

Data on access flow rates are highly variable. This infographic uses flow rates achieved through dedicated rapid infusers (ex. Level 1 ®) or at a pressure of 300mmHg. It is possible that rapid infusers and specialized pressure tubing achieve higher flow rates. The main references and additional sources are listed below. See this post from REBEL EM for gravity flow rates.

References

  1. Reddick AD, Ronald J, Morrison WG. Intravenous fluid resuscitation: was Poiseuille right? Emergency Medicine Journal. 2011;28(3):201-202. doi:10.1136/emj.2009.083485.
  2. Pasley J, Miller CHT, DuBose JJ, et al. Intraosseous infusion rates under high pressure. Journal of Trauma and Acute Care Surgery. 2015;78(2):295-299. doi:10.1097/TA.0000000000000516.
  3. Brown NJD, Duttchen KM, Caveno JW. An Evaluation of Flow Rates of Normal Saline through Peripheral and Central Venous Catheters. In:; 2008:1-2. http://www.asaabstracts.com/strands/asaabstracts/abstract.htm;jsessionid=451C60B7A9C145CBB6C147DBF022E267?year=2008&index=8&absnum=709.

Additional Sources

  1. Ngo AS-Y, Oh JJ, Chen Y, Yong D, Ong MEH. Intraosseous vascular access in adults using the EZ-IO in an emergency department. Int J Emerg Med. 2009;2(3):155-160. doi:10.1007/s12245-009-0116-9.
  2. Traylor S, Bastani A, Emergency NB-DAO, 2016. 311 Are Three Ports Better Than One? an Evaluation of Flow Rates Using All Ports of a Triple Lumen Central Venous Catheter in Volume Resuscitation. doi:10.1016/j.annemergmed.2016.08.327.
  3. Hammer N, Möbius R, Gries A, Hossfeld B, Bechmann I, Bernhard M. Comparison of the Fluid Resuscitation Rate with and without External Pressure Using Two Intraosseous Infusion Systems for Adult Emergencies, the CITRIN (Comparison of InTRaosseous infusion systems in emergency medicINe)-Study. Raju R, ed. PLoS ONE. 2015;10(12):e0143726–15. doi:10.1371/journal.pone.0143726.
  4. Ong MEH, Chan YH, Oh JJ, Ngo AS-Y. An observational, prospective study comparing tibial and humeral intraosseous access using the EZ-IO. Am J Emerg Med. 2009;27(1):8-15. doi:10.1016/j.ajem.2008.01.025.
  5. Philbeck TE, Miller LJ, Montez D, Puga T. Hurts so good. Easing IO pain and pressure. JEMS. 2010;35(9):58–62–65–6–68–quiz69. doi:10.1016/S0197-2510(10)70232-1.
  6. FRCA SIK, MRCA PRG, FRCA KP, MBChB SW, FRCA TS, MRCP PRG. Flow rates through intravenous access devices: an in vitro study. J Clin Anesth. 2016;31:101-105. doi:10.1016/j.jclinane.2016.01.048.
  7. Puga T, Montez D, Care TPC, 2016. 263: ADEQUACY OF INTRAOSSEOUS VASCULAR ACCESS INSERTION SITES FOR HIGH-VOLUME FLUID INFUSION. journalslwwcom
  8. Tan BKK, Chong S, Koh ZX, Ong MEH. EZ-IO in the ED: an observational, prospective study comparing flow rates with proximal and distal tibia intraosseous access in adults. Am J Emerg Med. 2012;30(8):1602-1606. doi:10.1016/j.ajem.2011.10.025.

Hypertensive Emergency

Brief HPI:

A 62 year-old female with a history of hypertension, diabetes and coronary artery disease is brought to the emergency department with altered mental status. The patient is confused and unable to provide history. Her family note that symptoms have been gradually worsening for the past one day and she had previously been in her usual state of good health. There was no history of recent illness, medication changes, recreational substance use, sick contacts, or travel.

On evaluation, vital signs were notable for hypertension (224/120mmHg, comparable on all extremities) though otherwise normal including afebrile core temperature – capillary glucose was 114mg/dL. On examination, the patient was awake and alert, making coordinated movements symmetrically in all four extremities without hyperreflexia or increased tone. Speech was unintelligible and the patient was unable to follow simple commands.

Labs/Imaging

Laboratory tests were notable for a serum creatinine of 1.2mg/dL (baseline unknown) but otherwise normal including CBC, troponin, TSH, and UA. ECG demonstrated left ventricular hypertrophy without acute ischemic changes. Imaging including chest radiograph and CT head non-contrast and CTA brain/neck were normal. Lumbar puncture was performed and CSF was normal.

Hospital Course

The patient was initiated on a continuous infusion of nicardipine for presumed hypertensive encephalopathy and admitted to the medical intensive care unit. An MRI was performed on hospital day 1 and demonstrated chronic microvascular ischemic changes. The patient’s mental status gradually improved over the course of her hospitalization and she was discharged home on hospital day 4.

An Algorithm for the Evaluation and Management of Hypertensive Emergencies

An Algorithm for the Evaluation and Management of Hypertensive Emergencies

References

General

  1. Lloyd-Jones DM, Morris PB, Ballantyne CM, et al. 2017 Focused Update of the 2016 ACC Expert Consensus Decision Pathway on the Role of Non-Statin Therapies for LDL-Cholesterol Lowering in the Management of Atherosclerotic Cardiovascular Disease Risk: A Report of the American College of Cardiology Task Force on Expert Consensus Decision Pathways. In: Vol 70. 2017:1785-1822. doi:10.1016/j.jacc.2017.07.745.
  2. Janke AT, McNaughton CD, Brody AM, Welch RD, Levy PD. Trends in the Incidence of Hypertensive Emergencies in US Emergency Departments From 2006 to 2013. J Am Heart Assoc. 2016;5(12). doi:10.1161/JAHA.116.004511.
  3. Rodriguez MA, Kumar SK, De Caro M. Hypertensive crisis. Cardiology in Review. 2010;18(2):102-107. doi:10.1097/CRD.0b013e3181c307b7.
  4. Katz JN, Gore JM, Amin A, et al. Practice patterns, outcomes, and end-organ dysfunction for patients with acute severe hypertension: the Studying the Treatment of Acute hyperTension (STAT) registry. Am Heart J. 2009;158(4):599–606.e1. doi:10.1016/j.ahj.2009.07.020.
  5. Elliott WJ. Clinical features in the management of selected hypertensive emergencies. Prog Cardiovasc Dis. 2006;48(5):316-325. doi:10.1016/j.pcad.2006.02.004.
  6. Aggarwal M, Khan IA. Hypertensive crisis: hypertensive emergencies and urgencies. Cardiol Clin. 2006;24(1):135-146. doi:10.1016/j.ccl.2005.09.002.
  7. Varon J, Marik PE. Clinical review: the management of hypertensive crises. Crit Care. 2003;7(5):374-384. doi:10.1186/cc2351.
  8. Shayne PH, Pitts SR. Severely increased blood pressure in the emergency department. YMEM. 2003;41(4):513-529. doi:10.1067/mem.2003.114.
  9. Vaughan CJ, Delanty N. Hypertensive emergencies. The Lancet. 2000;356(9227):411-417. doi:10.1016/S0140-6736(00)02539-3.

Ischemic Stroke

  1. Powers WJ, Rabinstein AA, Ackerson T, et al. 2018 Guidelines for the Early Management of Patients With Acute Ischemic Stroke: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association. Stroke. 2018;49(3):e46-e110. doi:10.1161/STR.0000000000000158.

Hemorrhagic Stroke

  1. Hemphill JC, Greenberg SM, Anderson CS, et al. Guidelines for the Management of Spontaneous Intracerebral Hemorrhage: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association. Stroke. 2015;46(7):2032-2060. doi:10.1161/STR.0000000000000069.

Subarachnoid Hemorrhage

  1. Connolly ES, Rabinstein AA, Carhuapoma JR, et al. Guidelines for the management of aneurysmal subarachnoid hemorrhage: a guideline for healthcare professionals from the American Heart Association/american Stroke Association. Stroke. 2012;43(6):1711-1737. doi:10.1161/STR.0b013e3182587839.

Renal

  1. Gillies MA, Kakar V, Parker RJ, Honoré PM, Ostermann M. Fenoldopam to prevent acute kidney injury after major surgery-a systematic review and meta-analysis. Crit Care. 2015;19(1):449. doi:10.1186/s13054-015-1166-4.
  2. Tumlin JA, Dunbar LM, Oparil S, et al. Fenoldopam, a dopamine agonist, for hypertensive emergency: a multicenter randomized trial. Fenoldopam Study Group. Academic Emergency Medicine. 2000;7(6):653-662.
  3. Shusterman NH, Elliott WJ, White WB. Fenoldopam, but not nitroprusside, improves renal function in severely hypertensive patients with impaired renal function. Am J Med. 1993;95(2):161-168.

Aortic Disease

  1. Hiratzka LF, Bakris GL, Beckman JA, et al. 2010 ACCF/AHA/AATS/ACR/ASA/SCA/SCAI/SIR/STS/SVM guidelines for the diagnosis and management of patients with Thoracic Aortic Disease: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines, American Association for Thoracic Surgery, American College of Radiology, American Stroke Association, Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, Society of Interventional Radiology, Society of Thoracic Surgeons, and Society for Vascular Medicine. Circulation. 2010;121(13):e266-e369. doi:10.1161/CIR.0b013e3181d4739e.

Pregnancy

  1. Townsend R, O’Brien P, Khalil A. Current best practice in the management of hypertensive disorders in pregnancy. Integr Blood Press Control. 2016;9:79-94. doi:10.2147/IBPC.S77344.
  2. Al-Safi Z, Imudia AN, Filetti LC, Hobson DT, Bahado-Singh RO, Awonuga AO. Delayed Postpartum Preeclampsia and Eclampsia. Obstet Gynecol. 2011;118(5):1102-1107. doi:10.1097/AOG.0b013e318231934c.
  3. Hypertension in pregnancy: diagnosis and management. National Institute for Health and Care Excellence. https://www.nice.org.uk/guidance/cg107. Published August 1, 2010. Accessed May 20, 2019.

Cerebrospinal Fluid

Brief HPI:

An approximately 70 year-old male with unknown medical history is brought to the emergency department with altered mental status. A community member contacted police after not seeing the patient for the past three days which was unusual. Upon entering the patient’s home, EMS found the patient on the ground, unresponsive. Capillary glucose was normal and naloxone was administered without appreciable effect.

On arrival in the emergency department, the patient remained unresponsive to verbal and noxious stimulation and was intubated for airway protection. Vital signs were notable for hypotension (BP 88/45mmHg) and a core temperature of 96.5°F. Physical examination demonstrated cool extremities and ecchymosis and edema involving the right upper and lower extremities. The patient’s blood pressure improved with fluid resuscitation and empiric broad-spectrum antibiotics were administered due to concern for infection in the setting of hypothermia.

Laboratory/Imaging Results

Laboratory tests were notable for leukocytosis and creatine kinase above the threshold for detection. Radiology preliminary interpretation of non-contrast head imaging was normal. A lumbar puncture was performed with grossly purulent cerebrospinal fluid.

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MRI Brain

Dependent material within the occipital horns of the lateral ventricles consistent with ventriculitis.

Hospital Course

The patient was admitted for the treatment of presumed meningitis. Radiology final interpretation of non-contrast head computed tomography commented on ventricular debris suggestive of ventriculitis which was later confirmed on magnetic resonance imaging1,2. Due to poor response to systemic antibiotics, neurosurgery was consulted, a ventricular drain was placed with administration of intrathecal antibiotics. The patient’s condition continued to deteriorate and family members elected to allow his natural death.

An Algorithm for the Analysis of Cerebrospinal Fluid (CSF)3-14

An Algorithm for the Analysis of Cerebrospinal Fluid (CSF)

References

  1. Lesourd A, Magne N, Soares A, et al. Primary bacterial ventriculitis in adults, an emergent diagnosis challenge: report of a meningoccal case and review of the literature. BMC Infect Dis. 2018;18(1):226. doi:10.1186/s12879-018-3119-4.
  2. Gofman N, To K, Whitman M, Garcia-Morales E. Successful treatment of ventriculitis caused by Pseudomonas aeruginosa and carbapenem-resistant Klebsiella pneumoniae with i.v. ceftazidime-avibactam and intrathecal amikacin. Am J Health Syst Pharm. 2018;75(13):953-957. doi:10.2146/ajhp170632.
  3. Dorsett M, Liang SY. Diagnosis and Treatment of Central Nervous System Infections in the Emergency Department. Emerg Med Clin North Am. 2016;34(4):917-942. doi:10.1016/j.emc.2016.06.013.
  4. Perry JJ, Alyahya B, Sivilotti MLA, et al. Differentiation between traumatic tap and aneurysmal subarachnoid hemorrhage: prospective cohort study. BMJ. 2015;350:h568. doi:10.1136/bmj.h568.
  5. Lee SCM, Lueck CJ. Cerebrospinal fluid pressure in adults. J Neuroophthalmol. 2014;34(3):278-283. doi:10.1097/WNO.0000000000000155.
  6. Brouwer MC, Thwaites GE, Tunkel AR, van de Beek D. Dilemmas in the diagnosis of acute community-acquired bacterial meningitis. Lancet. 2012;380(9854):1684-1692. doi:10.1016/S0140-6736(12)61185-4.
  7. Wright BLC, Lai JTF, Sinclair AJ. Cerebrospinal fluid and lumbar puncture: a practical review. J Neurol. 2012;259(8):1530-1545. doi:10.1007/s00415-012-6413-x.
  8. Gorchynski J, Oman J, Newton T. Interpretation of traumatic lumbar punctures in the setting of possible subarachnoid hemorrhage: who can be safely discharged? Cal J Emerg Med. 2007;8(1):3-7.
  9. Deisenhammer F, Bartos A, Egg R, et al. Guidelines on routine cerebrospinal fluid analysis. Report from an EFNS task force. Eur J Neurol. 2006;13(9):913-922. doi:10.1111/j.1468-1331.2006.01493.x.
  10. Seehusen DA, Reeves MM, Fomin DA. Cerebrospinal fluid analysis. Am Fam Physician. 2003;68(6):1103-1108.
  11. Shah KH, Edlow JA. Distinguishing traumatic lumbar puncture from true subarachnoid hemorrhage. J Emerg Med. 2002;23(1):67-74.
  12. Walker HK, Hall WD, Hurst JW. Clinical Methods: The History, Physical, and Laboratory Examinations. 1990.
  13. Mayefsky JH, Roghmann KJ. Determination of leukocytosis in traumatic spinal tap specimens. Am J Med. 1987;82(6):1175-1181.
  14. Geiseler PJ, Nelson KE, Levin S, Reddi KT, Moses VK. Community-acquired purulent meningitis: a review of 1,316 cases during the antibiotic era, 1954-1976. Rev Infect Dis. 1980;2(5):725-745.

Pleural Fluid

Brief HPI:

A 43 year-old female with no reported medical history presents with shortness of breath. She notes 2 months of gradually worsening symptoms associated with unproductive cough and intermittent subjective fevers. Symptoms are worsened with activity and when laying flat. She has no history of similar symptoms in the past.

Vital signs are notable for tachycardia, tachypnea and hypoxia. Examination demonstrates absent breath sounds in the entire right lung field. A plain chest radiograph is obtained and shown below. The patient was placed on non-invasive positive pressure with minimal improvement and an emergent therapeutic thoracentesis was performed. Pleural fluid was exudative and a large volume was submitted for cytology.

Whiteout right lung field Whiteout right lung field

An Algorithm for the Analysis of Pleural Fluid

An Algorithm for the Analysis of Pleural Fluid

References

  1. Light RW, Girard WM, Jenkinson SG, George RB. Parapneumonic effusions. Am J Med. 1980;69(4):507-512.
  2. Heffner JE, Brown LK, Barbieri CA. Diagnostic value of tests that discriminate between exudative and transudative pleural effusions. Primary Study Investigators. Chest. 1997;111(4):970-980. doi:10.1378/chest.111.4.970.
  3. Romero S, Martinez A, Hernandez L, et al. Light’s criteria revisited: consistency and comparison with new proposed alternative criteria for separating pleural transudates from exudates. Respiration. 2000;67(1):18-23. doi:10.1159/000029457.
  4. Light RW. Clinical practice. Pleural effusion. N Engl J Med. 2002;346(25):1971-1977. doi:10.1056/NEJMcp010731.
  5. Sahn SA, Huggins JT, San Jose E, Alvarez-Dobano JM, Valdes L. The Art of Pleural Fluid Analysis. Clinical Pulmonary Medicine. 2013;20(2):77-96. doi:10.1097/CPM.0b013e318285ba37.
  6. Light RW. The Light criteria: the beginning and why they are useful 40 years later. Clinics in Chest Medicine. 2013;34(1):21-26. doi:10.1016/j.ccm.2012.11.006.
  7. Aggarwal AN, Agarwal R, Sehgal IS, Dhooria S, Behera D. Meta-analysis of Indian studies evaluating adenosine deaminase for diagnosing tuberculous pleural effusion. Int J Tuberc Lung Dis. 2016;20(10):1386-1391. doi:10.5588/ijtld.16.0298.

Stroke

Brief HPI:

An approximately 60 year-old male with a history of hypertension and diabetes is brought to the emergency department after noting difficulty speaking and right-sided weakness upon awakening. Prehospital capillary glucose measured 268mg/dL. He went to sleep at 10pm on the evening prior to presentation.

The patient arrives in the emergency department awake and alert at 9am. He was unable to provide history due to speech difficulty but is able to follow commands. Examination demonstrates right upper and lower extremity weakness. Computed tomography of the head and neck is obtained, non-contrast imaging shows no hemorrhage and angiography demonstrates left MCA occlusion. He proceeds emergently to the angiography suite where mechanical thrombectomy restores normal perfusion. The patient is discharged to an inpatient rehabilitation facility for intensive physical therapy three days later.

CT Angiography

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CT Angiography

Left MCA M1 occlusion

Code Stroke Algorithm

Code Stroke Algorithm

References

  1. Goldstein LB, Simel DL. Is this patient having a stroke? JAMA. 2005;293(19):2391-2402. doi:10.1001/jama.293.19.2391.
  2. Hemmen TM, Meyer BC, McClean TL, Lyden PD. Identification of nonischemic stroke mimics among 411 code strokes at the University of California, San Diego, Stroke Center. J Stroke Cerebrovasc Dis. 2008;17(1):23-25. doi:10.1016/j.jstrokecerebrovasdis.2007.09.008.
  3. Prabhakaran S, Ruff I, Bernstein RA. Acute stroke intervention: a systematic review. JAMA. 2015;313(14):1451-1462. doi:10.1001/jama.2015.3058.
  4. Yew KS, Cheng EM. Diagnosis of acute stroke. Am Fam Physician. 2015;91(8):528-536.
  5. Hemphill JC, Greenberg SM, Anderson CS, et al. Guidelines for the Management of Spontaneous Intracerebral Hemorrhage: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association. Stroke. 2015;46(7):2032-2060. doi:10.1161/STR.0000000000000069.
  6. Hankey GJ. Stroke. Lancet. 2017;389(10069):641-654. doi:10.1016/S0140-6736(16)30962-X.
  7. Powers WJ, Rabinstein AA, Ackerson T, et al. 2018 Guidelines for the Early Management of Patients With Acute Ischemic Stroke: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association. Stroke. 2018;49(3):e46-e110. doi:10.1161/STR.0000000000000158.
  8. Hasan TF, Rabinstein AA, Middlebrooks EH, et al. Diagnosis and Management of Acute Ischemic Stroke. Mayo Clin Proc. 2018;93(4):523-538. doi:10.1016/j.mayocp.2018.02.013.
  9. Thomalla G, Simonsen CZ, Boutitie F, et al. MRI-Guided Thrombolysis for Stroke with Unknown Time of Onset. N Engl J Med. 2018;379(7):611-622. doi:10.1056/NEJMoa1804355.

Synovial Fluid

Brief HPI:

A 38 year-old female with a history of obesity and obstructive sleep apnea presents with right knee pain. She cannot identify a clear precipitant for her symptoms which she first noted 2 weeks ago. Her pain is worsened with ambulation and while previously tolerable, has grown more severe despite over-the-counter analgesics over the past two days. She denies fevers, intravenous drug use, recent travel or instrumentation.

On evaluation, vital signs are normal. Physical examination demonstrates a moderate-sized right knee effusion with overlying warmth though no edema. There is minimal pain with range of motion, no pain with heel percussion, and she is ambulatory independently with a mildly antalgic gait. Clinical suspicion for septic arthritis was low. A diagnostic arthrocentesis was performed without complication. Synovial fluid was less-viscous than normal with slight debris. Laboratory analysis revealed 14,230 white blood cells with 85% neutrophils and no crystals visualized. The patient was discharged with supportive care and outpatient follow-up – cultures were ultimately negative.

An Algorithm for the Analysis of Synovial Fluid

An Algorithm for the Analysis of Synovial Fluid

References

  1. Margaretten ME, Kohlwes J, Moore D, Bent S. Does this adult patient have septic arthritis? JAMA. 2007;297(13):1478-1488. doi:10.1001/jama.297.13.1478.
  2. Brannan SR, Jerrard DA. Synovial fluid analysis. J Emerg Med. 2006;30(3):331-339. doi:10.1016/j.jemermed.2005.05.029.
  3. Couderc M, Pereira B, Mathieu S, et al. Predictive value of the usual clinical signs and laboratory tests in the diagnosis of septic arthritis. CJEM. 2015;17(4):403-410. doi:10.1017/cem.2014.56.
  4. MD HJC, MD LAB, MD ML. Septic Arthritis. Hospital Medicine Clinics. 2014;3(4):494-503. doi:10.1016/j.ehmc.2014.06.009.

Ascitic Fluid

Brief HPI:

A 56 year-old male with a history of alcoholic cirrhosis complicated by esophageal varices presents to the emergency department with abdominal distension. He notes gradually worsening symptoms over the past 2 weeks – roughly correlating with the timing of his last paracentesis. He has limited access to medical care and typically presents to emergency departments for palliative paracenteses. He is otherwise in his usual state of health and denies fevers, chills, abdominal pain, vomiting blood, or dark/bloody stools.

Vital signs are notable for a heart rate of 97bpm and blood pressure of 110/65mmHg – otherwise normal. Examination demonstrates a distended abdomen which is non-tender, dull to percussion and with a palpable fluid wave. Bedside ultrasonography shows large, homogenous-appearing ascites with readily-accessible pockets for drainage in the bilateral lower quadrants. A palliative paracentesis is performed with uncomplicated extraction of 4 liters of translucent, straw-colored fluid. Ascitic fluid analysis shows 90 white blood cells of which 10% are polymorphonuclear. The patient is observed briefly in the emergency department, noted symptomatic improvement and was discharged with a plan for telephone follow-up of fluid culture results.

An Algorithm for the Analysis of Ascitic Fluid

Algorithm for the Analysis of Ascitic Fluid

References

  1. Runyon BA. Care of patients with ascites. N Engl J Med. 1994;330(5):337-342. doi:10.1056/NEJM199402033300508.
  2. Wong CL, Holroyd-Leduc J, Thorpe KE, Straus SE. Does this patient have bacterial peritonitis or portal hypertension? How do I perform a paracentesis and analyze the results? JAMA. 2008;299(10):1166-1178. doi:10.1001/jama.299.10.1166.
  3. Tarn AC, Lapworth R. Biochemical analysis of ascitic (peritoneal) fluid: what should we measure? Ann Clin Biochem. 2010;47(Pt 5):397-407. doi:10.1258/acb.2010.010048.
  4. Li PK-T, Szeto CC, Piraino B, et al. ISPD Peritonitis Recommendations: 2016 Update on Prevention and Treatment. Perit Dial Int. 2016;36(5):481-508. doi:10.3747/pdi.2016.00078.
  5. MacIntosh T. Emergency Management of Spontaneous Bacterial Peritonitis – A Clinical Review. Cureus. 2018;10(3):e2253. doi:10.7759/cureus.2253.

Resuscitative Thoracotomy

Brief HPI:

A call is received from pre-hospital providers regarding an inbound trauma patient. An estimated 30 year-old male with unknown history sustained a penetrating wound to the right flank. On EMS arrival the patient was unresponsive but had a weakly-palpable radial pulse which was lost en-route. Their estimated time of arrival is 5 minutes.

Algorithm for the Selection of Patients for Resuscitative Thoracotomy

Algorithm for the Selection of Patients for Resuscitative Thoracotomy

References:

  1. Seamon MJ, Haut ER, Van Arendonk K, Barbosa RR, Chiu WC, Dente CJ, et al. An evidence-based approach to patient selection for emergency department thoracotomy: A practice management guideline from the Eastern Association for the Surgery of Trauma. J Trauma Acute Care Surg. 2015 Jul;79(1):159–73.
  2. Burlew CC, Moore EE, Moore FA, Coimbra R, McIntyre RC, Davis JW, et al. Western Trauma Association critical decisions in trauma: resuscitative thoracotomy. J Trauma Acute Care Surg. 2012 Dec;73(6):1359–63.
  3. Sherren PB, Reid C, Habig K, Burns BJ. Algorithm for the resuscitation of traumatic cardiac arrest patients in a physician-staffed helicopter emergency medical service. Crit Care. 2013 Mar 12;17(2):308.
  4. Cothren CC, Moore EE. Emergency department thoracotomy for the critically injured patient: Objectives, indications, and outcomes. World J Emerg Surg. 2006 Mar 24;1:4.

Red and Painful Eye

Brief HPI

A 60-year-old female with rheumatoid arthritis presents with unilateral eye pain and redness without reported vision changes. Physical examination demonstrates radially-oriented engorged episcleral vessels and normal visual acuity – she was diagnosed with episcleritis and discharged with follow-up.

Algorithm for the Evaluation of the Red and Painful Eye

Algorithm for the Evaluation of the Red and Painful Eye

Overview

The red or painful eye is a common presentation in the emergency department and the rapid identification and management of potentially sight-threatening causes is critical.

The diagnostic approach to the red or painful eye begins with identifying a history of caustic exposure where immediate and copious irrigation (even before detailed examination) may limit further injury. Alkaline agents induce more severe liquefactive necrosis leading to keratoconjunctivitis, while acidic agents are generally less destructive. Management is identical for both: irrigation with lactated Ringer solution through a Morgan lens applied to a topically anesthetized eye for 5-10 minutes repeated until the pH of the eye is neutral1.

Ocular or facial trauma presents a spectrum of differential diagnoses. Suspicion for globe rupture is increased by a suggestive mechanism such as a high-velocity projectile or high-impact blunt facial trauma. Characteristic examination findings include obvious globe deformity, an irregularly-shaped pupil, extrusion of vitreous, markedly decreased visual acuity, or parting of fluorescein (Seidel sign). If globe rupture is suspected, further manipulation is unadvisable and the affected eye should be shielded. Measures should be taken to avoid increases in intra-ocular pressure including elevation of the patient’s head-of-bed, anti-emetics (to prevent intra-ocular hypertension with vomiting), and the avoidance of medications potentially implicated in intra-ocular hypertension (ketamine, succinylcholine). Tetanus and antimicrobial prophylaxis should be provided while awaiting emergent ophthalmology consultation2,3.

Another traumatic diagnosis warranting rapid identification and possible intervention is retrobulbar hematoma – identified by proptosis, eye pain, decreased visual acuity, and elevated intra-ocular pressure. Pressures exceeding 40mmHg warrant lateral cantholysis in conjunction with medical management to prevent optic nerve ischemia and preserve vision4,5.

Diagnostic Approach

The evaluation of the non-traumatic red or painful eye follows a systematic and anatomically-based approach, starting with external components and moving inward:

1. External

The examination begins externally with an assessment of function (visual acuity) and inspection and palpation of the periorbital region. Periorbital edema, erythema, and tenderness to palpation in the setting of systemic illness (fever) is concerning for orbital cellulitis. When associated with elevated intra-ocular pressure or proptosis, a retrobulbar abscess may be present. Both warrant admission and parenteral antibiotics and the latter may require operative management such as aspiration or cantholysis. Less severe features without impact on visual acuity is suggestive of a periorbital cellulitis which may be treated as an outpatient with close follow-up2,6.

2. Lids and Lashes

Several non-emergent processes may affect the lids and lashes including blepharitis (inflammation of the eyelid margin), chalazion (inflammation of the Meibomian glands), hordeolum (eyelash follicle abscess), or dacrocystitis (infection of the lacrimal sac)2,7,8.

3. Conjunctiva and Sclera

Again, proceeding from superficial to deeper structures we encounter the epithelial layer (including palpebral and bulbar components) covering the sclera which is subject to allergic or infectious inflammation. Conjunctivitis is characterized by engorgement of superficial conjunctival blood vessels, potentially associated with conjunctival edema (chemosis), or discharge. Most conjunctivitis is self-limited and not sight-threatening, treatment is aimed at symptomatic relief though topical antibiotics have few adverse effects and may be prescribed if the diagnosis of bacterial conjunctivitis is unclear9.

When associated with pain, a deeper inflammatory process is implicated. Scleritis is a frequently immune-mediated inflammatory process (though infection, malignancy and medications have been implicated) associated with pain, photophobia, and examination findings of globe tenderness and engorged scleral blood vessels. Management in the emergency department is trivial (systemic NSAID’s), however ophthalmology consultation should be secured due to the risk of vision-compromising complications, as well as the intimation of an underlying systemic disorder9,10. Episcleritis is similarly immune-mediated, though generally self-limiting. The diagnosis is made by identification of characteristic, radially-oriented engorged episcleral vessels. When the diagnosis of scleritis versus episcleritis or conjunctivitis is in question the application of a topical vasoconstrictor (phenylephrine 2.5%) will blanch vessels in the conjunctival or superficial episcleral plexuses – sparing scleral vessels10,11.

4. Cornea

Keratitis can be caused by infection, ultraviolet light exposure, or contact lens use. Patients may have photophobia and a foreign-body sensation. Gross inspection or slit-lamp examination will show epithelial erosions that stain with fluorescein or the characteristic dendritic pattern accompanying herpes simplex virus infection. Management includes ophthalmology consultation, topical antibiotics if a bacterial process is suggested, and close follow-up7-9,12.

5. Anterior Chamber

A critical process occurring in the anterior chamber is angle-closure glaucoma. The patient commonly presents with severe pain, circumcorneal injection, and a pupil fixed at mid-dilation. Diagnosis is confirmed by the measurement of elevated intra-ocular pressure (greater than 20mmHg). Reduction of intra-ocular pressure with topical and systemic agents should begin immediately while awaiting emergent ophthalmology consultation13.

The slit-lamp microscope facilitates examination of the anterior chamber. The presence of cells (floating white and red blood cells, or layering hypopyon or hyphema) and flare (protein) suggest inflammation in the anterior segment caused by a systemic inflammatory process, infection, or trauma and warrants close ophthalmologic follow-up2,7,9.

6. Vitreous

An ocular examination mimicking orbital cellulitis with evidence of anterior chamber involvement, particularly in a patient with a history of recent ocular surgery or trauma suggests endophthalmitis. Management requires admission for parenteral antibiotics with ophthalmology consultation2.

Additional Diagnostic Modalities

Advanced imaging may be useful in the diagnosis of traumatic and non-traumatic orbital pathology. Multi-detector computed tomography (MD-CT) is readily available and rapidly performed in the emergency department and can aid in the diagnosis of critical infectious processes, including extension beyond the orbital septum in orbital cellulitis, scleral thickening in endophthalmitis, and characterization of hematoma or abscess in the retrobulbar space. The addition of intravenous contrast media can identify critical vascular processes such as cavernous sinus thrombosis14,15. For traumatic pathology, CT can assist with the evaluation of globe integrity, lens position, vitreous/retinal detachment, and foreign bodies16. Imaging cannot be relied upon exclusively to exclude pathology, and the patient’s presentation and clinician’s examination should determine the need for consultation and evaluation. For globe rupture, for example, in one study of 59 patients with severe ocular trauma and diagnostic uncertainty regarding the presence of globe rupture, CT failed to diagnosed open globe injury in 1/3 of patients (with surgical scleral inspection as a reference standard)17. Another retrospective analysis of 48 eyes sustaining trauma revealed sensitivity ranging from 56-68% for CT identification of open globe injury18.

In addition to potential diagnostic inaccuracy, computed tomography exposes patients to risks including ionizing radiation, and the possibility of contrast-induced nephropathy19. Ultrasound is becoming increasingly accessible and comfortable for the emergency physician, and has the benefit of being relatively non-invasive – including facilitating ocular examination in patients with significant periorbital swelling limiting eye-opening. Ocular ultrasound may aid with the diagnosis of a wide variety of ocular pathology including vitreous hemorrhage, retinal detachment, central retinal arterial/venous occlusions, foreign body identification, lens dislocation and retrobulbar hematoma. In one study of 61 patients presenting with trauma or acute vision changes, ultrasound interpretation agreed with criterion standard (orbital computed tomography or ophthalmology evaluation) for 98% of cases20.

View Ocular Ultrasound Algorithm

References

  1. Messman AM. Ocular Injuries: New Strategies In Emergency Department Management. Emergency Medicine Practice. 2015;17(11):1–21–quiz21–2.
  2. Wright JL, Wightman JM. Red and painful eye. … Concepts and Clinical Practice 8th ed …. 2014.
  3. Romaniuk VM. Ocular trauma and other catastrophes. Emerg Med Clin North Am. 2013;31(2):399-411. doi:10.1016/j.emc.2013.02.003.
  4. Babineau MR, Sanchez LD. Ophthalmologic Procedures in the Emergency Department. Emerg Med Clin North Am. 2008;26(1):17-34. doi:10.1016/j.emc.2007.11.003.
  5. Rowh AD, Ufberg JW, Chan TC, Vilke GM, Harrigan RA. Lateral canthotomy and cantholysis: emergency management of orbital compartment syndrome. J Emerg Med. 2015;48(3):325-330. doi:10.1016/j.jemermed.2014.11.002.
  6. Henderson M, Tierney L, Smetana G. The Patient History: Evidence-Based Approach. McGraw Hill Professional; 2012.
  7. Alteveer JG, Mccans KM, Hemphill RR. The Red Eye, The Swollen Eye, And Acute Vision Loss. … Practice+ Em Practice …. 2002.
  8. Leibowitz HM. The red eye. N Engl J Med. 2000;343(5):345-351. doi:10.1056/NEJM200008033430507.
  9. Mahmood AR, Narang AT. Diagnosis and management of the acute red eye. Emerg Med Clin North Am. 2008. doi:10.1016/j.emc.2007.10.002.
  10. Albini TA, Rao NA, Smith RE. The Diagnosis and Management of Anterior Scleritis. International Ophthalmology Clinics. 2005;45(2):191.
  11. Roscoe M, Landis T. How to diagnose the acute red eye with confidence. JAAPA. 2006;19(3):24–30–quiz45–6.
  12. Deborah S Jacobs MD. Evaluation of the red eye. UpToDate. https://www.uptodate.com/contents/evaluation-of-the-red-eye. Published February 24, 2016. Accessed April 18, 2017.
  13. Prum BE, Herndon LW, Moroi SE, et al. Primary Angle Closure Preferred Practice Pattern(®) Guidelines. Ophthalmology. 2016;123(1):P1-P40. doi:10.1016/j.ophtha.2015.10.049.
  14. LeBedis CA, Sakai O. Nontraumatic orbital conditions: diagnosis with CT and MR imaging in the emergent setting. Radiographics. 2008;28(6):1741-1753. doi:10.1148/rg.286085515.
  15. Platnick J, Crum AV, Soohoo S, Cedeño PA, Johnson MH. The globe: infection, inflammation, and systemic disease. YSULT. 2011;32(1):38-50. doi:10.1053/j.sult.2010.12.003.
  16. Dunkin JM, Crum AV, Swanger RS, Bokhari SAJ. Globe trauma. YSULT. 2011;32(1):51-56. doi:10.1053/j.sult.2010.09.003.
  17. Hoffstetter P, Schreyer AG, Schreyer CI, et al. Multidetector CT (MD-CT) in the diagnosis of uncertain open globe injuries. Rofo. 2010;182(2):151-154. doi:10.1055/s-0028-1109659.
  18. Arey ML, Mootha VV, Whittemore AR, Chason DP, Blomquist PH. Computed tomography in the diagnosis of occult open-globe injuries. Ophthalmology. 2007;114(8):1448-1452. doi:10.1016/j.ophtha.2006.10.051.
  19. Custer PL, Kent TL. Pitfalls of ophthalmic radiographic imaging. Curr Opin Ophthalmol. 2014;25(5):432-435. doi:10.1097/ICU.0000000000000064.
  20. Blaivas M, Theodoro D, Sierzenski PR. A study of bedside ocular ultrasonography in the emergency department. Academic Emergency Medicine. 2002;9(8):791-799.

Pericardial Effusion

HPI:

43F with a history of HTN and diastolic heart failure presenting with two days of shortness of breath. Reports that symptoms are worse at night when lying down to sleep and associated with a cough productive of white sputum. She also reports intermittent left-sided chest pain, described as sharp and exacerbated by cough or deep inspiration. She denies fevers/chills, nausea/vomiting, sick contacts or recent travel.
m

PMH:

  • Hypertension
  • Diabetes Mellitus (Type II)
  • Hyperlipidemia
  • Diastolic heart failure

PSH:

  • Cesarean section

FH:

  • Father with MI at 76 years-old

SHx:

  • Lives at home.
  • Denies tobacco, alcohol or drug abuse.

Meds:

  • Lasix 40mg p.o. daily
  • Lisinopril 20mg p.o. daily
  • Atenolol 50mg p.o. daily
  • Omeprazole 20mg p.o. daily
  • Lantus 14 units daily
  • Novolin 6 units t.i.d

Allergies:

NKDA

Physical Exam:

VS: T 98.2 HR 81 RR 19 BP 219/91 O2 95% RA
Gen: Adult female in no acute distress, alert and responding appropriately to questions.
HEENT: PERRL, EOMI, mucous membranes moist.
CV: RRR, no murmurs appreciated, no JVD.
Lungs: Crackles at right lung base.
Abd: Soft, non-tender, non-distended, without rebound/guarding.
Ext: 1+ pitting edema in bilateral lower extremities to knee.
Neuro: AAOx4, grossly normal peripheral sensation and motor strength.

Labs/Studies:

  • Troponin: 0.15
  • Procalcitonin: 0.15
  • CBC: 10.9/9.1/26.4/296
  • BMP: 134/4.6/104/22/56/2.87/214

Imaging:

Pericardial Effusion

Pericardial Effusion

Measured in the largest dimension, suggestive of a moderate to large pericardial effusion.

E-Point Septal Separation

E-Point Septal Separation

E-Point Septal Separation (EPSS), estimated here is the smallest distance between the anterior leaflet of the mitral valve and intraventricular septum. Values > 12mm are suggestive of depressed ejection fraction.

Left Ventricular Hypertrophy

Left Ventricular Hypertrophy

Thickened left ventricular wall.

Pericardial Effusion - Subxiphoid

Pericardial Effusion - Subxiphoid

Pericardial Effusion - Parasternal Long

Pericardial Effusion - Parasternal Long

Pericardial Effusion - Parasternal Short

Pericardial Effusion - Parasternal Short

  • CXR: Consolidation involving the majority of the right lung, cardiomegaly.
  • Bedside Echo: LVEF 55%, concentric LVH, no wall motion abnormality, moderate pericardial effusion noted, RV not collapsed.

Assessment/Plan:

43F with a history of HTN, diastolic heart failure presenting with SOB.

#SOB: CXR finding of right-sided consolidation with history of productive cough, evidence of leukocytosis with neutrophil predominance, and relative hypoxemia suggestive of community-acquired pneumonia. No evidence of systemic inflammatory response. PE unlikely, patient is not bed-bound and alternative diagnosis more likely.
– Start empiric antimicrobial therapy ceftriaxone 1g IV q24h, azithromycin 500mg IV q24h.

#Pericardial Effusion: Noted on bedside echo, no evidence of RV collapse to suggest cardiac tamponade. Also, no JVD and pulsus paradoxus measured at 8mmHg.
– Obtain formal transthoracic echocardiogram to evaluate effusion.
– Consult cardiology if worsening hemodynamics

#Elevated Troponin: No ECG changes suggestive of acute ST-elevation MI. May represent NSTEMI though historical features not consistent with ACS.
– Trend troponin/EKG q.8.h. x3
– Give aspirin 325mg, consider anti-coagulation.
– Consider stress echo prior to discharge

#Elevated Creatinine: Baseline unknown, likely acute component with or without chronic kidney disease.
– Volume resuscitation as tolerated, follow repeat chemistry.

#Hypertension: Asymptomatic, resume home medications.

Physiology of Cardiac Tamponade 1

  • Intrapericardial pressure (IPP) normally reflects intrathoracic pressure (ITP).
  • Inspiration: low ITP → low RAP → increased RA filling.
  • Expiration: high ITP → low LAP → increased LA filling.
  • Increased pericardial fluid → increased IPP → increased LA/RA filling pressures (diastolic dysfunction) → increased variation with respiration.
  • Earliest hemodynamic change in cardiac tamponade is JVD or IVC dilation.

IVC variation as marker for RAP 1

IVC Diameter (cm) Change with Respiration (%) RAP (mmHg)
<2.1 >50% 0-5
<2.1 <50% 5-10
>2.1 >50% 5-10
>2.1 <50% >15

Grading Pericardial Effusions 1

Grade Echo-free space (mm) Size (mL)
Small <10 100
Moderate 10-20 100-500
Large >20 >500

History and Physical Exam in Patients with Acute Pericarditis 2,3

Symptom/Sign ACS Pericarditis PE
Quality Pressure Sharp Sharp
Pleuritic No Yes Yes
Positional No Yes (worse when supine) No
Duration Minutes to hours Hours to days Hours to days
Improves with NG Yes No No
Friction Rub No Yes No
S3 Maybe No No

Differential Diagnosis of Pericardial Effusion 2-8

Differential Diagnosis of Pericardial Effusion

References:

  1. Schairer, J. R., Biswas, S., Keteyian, S. J., & Ananthasubramaniam, K. (2011). A Systematic Approach to Evaluation of Pericardial Effusion and Cardiac Tamponade. Cardiology in Review, 19(5), 233–238. doi:10.1097/CRD.0b013e31821e202c
  2. Khandaker MH, Espinosa RE, Nishimura RA, et al. Pericardial Disease: Diagnosis and Management. Mayo Clinic Proceedings. 2010;85(6):572-593. doi:10.4065/mcp.2010.0046.
  3. Lange, RA, Hillis, LD. Clinical practice. Acute pericarditis. The New England journal of medicine. 2004;351(21), 2195–2202. doi:10.1056/NEJMcp041997
  4. Imazio M, Adler Y. Management of pericardial effusion. Eur Heart J. 2013;34(16):1186-1197. doi:10.1093/eurheartj/ehs372.
  5. LeWinter MM. Clinical practice. Acute pericarditis. N Engl J Med. 2014;371(25):2410-2416. doi:10.1056/NEJMcp1404070.
  6. Vakamudi S, Ho N, Cremer PC. Pericardial Effusions: Causes, Diagnosis, and Management. Prog Cardiovasc Dis. 2017;59(4):380-388. doi:10.1016/j.pcad.2016.12.009.
  7. Imazio M, Mayosi BM, Brucato A, et al. Triage and management of pericardial effusion. J Cardiovasc Med (Hagerstown). 2010;11(12):928-935. doi:10.2459/JCM.0b013e32833e5788.
  8. Maisch B, Seferović PM, Ristić AD, et al. Guidelines on the diagnosis and management of pericardial diseases executive summary; The Task force on the diagnosis and management of pericardial diseases of the European society of cardiology. Eur Heart J. 2004;25(7):587-610. doi:10.1016/j.ehj.2004.02.002.

Low Voltage ECG

Definition

  • QRS in limb leads <5mm
  • QRS in precordial leads <10mm

General Causes

  • Fluid, fat or air attenuating signal
  • Myocardial infiltration
  • Loss of viable myocardium

Example

Low Voltage ECG
Low Voltage ECG

Low Voltage ECG

ECG of patient with pericardial effusion

Baseline ECG
Baseline ECG

Baseline ECG

Old ECG from same patient

Differential Diagnosis of Low Voltage ECG

Differential Diagnosis of Low-Voltage ECG

References

  1. Madias JE. Low QRS voltage and its causes. J Electrocardiol. 2008;41(6):498–500. doi:10.1016/j.jelectrocard.2008.06.021.
  2. WikEM: Low ECG voltage

Palpitations

Brief H&P

48F with a history of Grave disease (off medications for 4 months), presenting with palpitations. Noted gradual onset of palpitations while at rest, describing a pounding sensation lasting 3-4 hours and persistent (though improved) on presentation. Symptoms not associated with chest pain, shortness of breath, loss of consciousness, nor triggered by exertion. She reported a history of 8-10 episodes in the past for which she did not seek medical attention. Review of systems notable only for heat intolerance.

On physical examination, vital signs were notable for tachycardia (HR 138bpm). No alteration in mental status, murmur, tremor or hyperreflexia appreciated.

Labs

  • Hb: 14.7
  • Urine hCG: negative
  • TSH: <0.01
  • Total T3: 311ng/dL
  • Free T4: 2.64ng/dL

ECG

Palpitations - Sinus Tachycardia

Sinus Tachycardia

Impression/Plan

Palpitations due to sinus tachycardia from symptomatic hyperthyroidism secondary to medication non-adherence. Improved with propranolol, discharged with methimazole and PMD follow-up.

Algorithm for the Evaluation and Management of Palpitations1, 2

Algorithm for the Evaluation and Management of Palpitations

Evaluation of Palpitations

History and Physical

Subjective description of symptom quality
Rapid and regular beating suggests paroxysmal SVT or VT. Rapid and irregular beating suggests atrial fibrillation, atrial flutter, or variable conduction block.
Stop/start sensation: PAC or PVC
Rapid fluttering: Sustained supraventricular or ventricular tachycardia
Pounding in neck: Produced by canon A waves from AV dissociation (VT, complete heart block, SVT)
Onset and offset
Random, episodic, lasting instants: Suggests PAC or PVC
Gradual onset and offset: Sinus tachycardia
Abrupt onset and offset: SVT or VT
Syncope
Suggests hemodynamically significant arrhythmia, often VT
Examination
Identify evidence of structural, valvular heart disease

ECG1

ECG Finding Presumed etiology
Short PR, Delta waves WPW, AVRT
LAA, LVH Atrial fibrillation
PVC, BBB Idiopathic VT
Q-waves Prior MI, VT
QT-prolongation VT (polymorphic)
LVH, septal Q-waves HCM
Blocks  

References

  1. Zimetbaum P, Josephson ME. Evaluation of patients with palpitations. N Engl J Med. 1998;338(19):1369-1373. doi:10.1056/NEJM199805073381907.
  2. Probst MA, Mower WR, Kanzaria HK, Hoffman JR, Buch EF, Sun BC. Analysis of emergency department visits for palpitations (from the National Hospital Ambulatory Medical Care Survey). The American Journal of Cardiology. 2014;113(10):1685-1690. doi:10.1016/j.amjcard.2014.02.020.
  3. Abbott AV. Diagnostic approach to palpitations. Am Fam Physician. 2005;71(4):743-750.

Seizure

Brief HPI

A 72 year-old male with a history of hypertension and hiatal hernia presents to the emergency department with one week of generalized weakness. His family report decreased oral intake with frequent emesis over the past four days. He denies chest pain, shortness of breath, abdominal pain, or other complaints. During the interview he has a generalized tonic-clonic seizure which persists for five minutes despite the administration of 4mg of lorazepam.

An Algorithm for the Management of Seizures

The management of active seizures is algorithmic, starting with a rapid assessment of airway patency, supporting ventilation (with appropriate positioning, nasopharyngeal airway adjuncts and bag-valve mask if needed) and ensuring adequate perfusion. Patients should have continuous vital sign monitoring, supplemental oxygen to maintain oxygen saturation >92% and intravenous access1.

Pharmacologic treatment follows a stepwise approach, detailed in the algorithm below. The focus is on immediate stabilization and progressively escalating anti-epileptic drugs eventually requiring endotracheal intubation and continuous infusions of sedatives2-4.

An Algorithm for the Management of Seizures

Pathophysiology

Seizures are caused by excessive and disorganized neuronal activation, typically induced by global alterations in the production and transmission of impulses (electrolyte derangements, drugs/toxins, infection), or foci of increased irritability (hemorrhage, stroke, mass) – a pathophysiologic motif that mimics cardiac tachyarrhythmias (sympathomimetic toxicity or scarred myocardium for example)1. Status epilepticus, defined as a seizure lasting greater than five minutes or recurrent seizures without a return to normal baseline, shares an equally high short-term mortality – greater than 20%5.

Syncope vs. Seizure

The algorithm below details historical and examination features that may assist with distinguishing epileptic seizure from non-epileptic activity6,7.

Clinical Features Distinguishing Seizure from Syncope

Case Conclusion

The patient continued to seize and a point-of-care chemistry panel revealed a serum sodium of 108mEq/L. Seizures abate after the infusion of hypertonic saline (100mL of 3% saline over 10 minutes, repeated until cessation of seizures). While hyponatremia is generally corrected slowly – owing to the risk of osmotic demyelination – immediate correction in this setting is critical8.


The remainder of the patient’s evaluation demonstrated urine osmolarity is 389mOsm/kg and urine sodium is 53mmol/L, in the setting of relative euvolemia on examination these findings were consistent with SIADH. Head computed tomography is obtained and reveals a sellar mass.

View Hyponatremia Algorithm

References

  1. McMullan JT, Davitt AM, Pollack CV Jr. Seizures. In: Rosen’s Emergency Medicine. Mosby Incorporated; 2002:2808. doi:10.1016/S1474-4422(06)70350-7.
  2. Billington M, Kandalaft OR, Aisiku IP. Adult Status Epilepticus: A Review of the Prehospital and Emergency Department Management. J Clin Med. 2016;5(9):74. doi:10.3390/jcm5090074.
  3. Huff JS, Morris DL, Kothari RU, Gibbs MA, Emergency Medicine Seizure Study Group. Emergency department management of patients with seizures: a multicenter study. Academic Emergency Medicine. 2001;8(6):622-628.
  4. Prasad M, Krishnan PR, Sequeira R, Al-Roomi K. Anticonvulsant therapy for status epilepticus. Prasad M, ed. Cochrane Database Syst Rev. 2014;16(9):CD003723. doi:10.1002/14651858.CD003723.pub3.
  5. Logroscino G, Hesdorffer DC, Cascino G, Annegers JF, Hauser WA. Short-term mortality after a first episode of status epilepticus. Epilepsia. 1997;38(12):1344-1349.
  6. Sheldon R, Rose S, Ritchie D, et al. Historical criteria that distinguish syncope from seizures. J Am Coll Cardiol. 2002;40(1):142-148.
  7. McKeon A, Vaughan C, Delanty N. Seizure versus syncope. Lancet Neurol. 2006;5(2):171-180. doi:10.1016/S1474-4422(06)70350-7.
  8. Goh KP. Management of hyponatremia. Am Fam Physician. 2004;69(10):2387-2394.

Cardiac Arrest

Brief HPI:

An overhead page alerts you to an arriving patient with cardiac arrest. An approximately 35-year-old male was running away from police officers and collapsed after being shot with a stun gun. The patient was found to be pulseless, CPR was started by police officers and the patient is en route.

An Algorithm for the Evaluation and Management of Cardiac Arrest with Ultrasonography

An Algorithm for the Evaluation and Management of Cardiac Arrest with Ultrasonography

Causes of Cardiac (and non-cardiac) Arrest

Sudden cardiac arrest (SCA) leading to sudden cardiac death (SCD) if not successfully resuscitated, refers to the unexpected collapse of circulatory function. Available epidemiologic data for in-hospital and out-of-hospital cardiac arrest (OHCA) point appropriately to cardiac processes as the most common cause, though extra-cardiac processes (most frequently respiratory), comprise up to 40% of cases1-3.

Identifying the underlying cause is critical as several reversible precipitants require rapid identification. However, the usual diagnostic techniques may be challenging, limited or absent – including patient history, detailed examination, and diagnostic studies.

The initial rhythm detected upon evaluation is most suggestive of the etiologic precipitant. Pulseless ventricular tachycardia (pVT) or ventricular fibrillation (VF) is suggestive of a cardiac process – most commonly an acute coronary syndrome although heart failure or other structural and non-structural heart defects associated with dysrhythmias may be at fault4.

Pulseless electrical activity (PEA) presents a broader differential diagnosis as it essentially represents severe shock. The most common extra-cardiac cause is hypoxia – commonly secondary to pulmonary processes including small and large airway obstruction (bronchospasm, aspiration, foreign body, edema). Other causes include substance intoxication, medication adverse effect5,6, or electrolyte disturbances7. Finally, any precipitant of shock may ultimately lead to PEA, including hypovolemia/hemorrhage, obstruction (massive pulmonary embolus8, tamponade, tension pneumothorax), and distribution (sepsis).

Asystole is the absence of even disorganized electrical discharge and is the terminal degeneration of any of the previously-mentioned rhythms if left untreated.

Management of Cardiac Arrest

Optimizing survival outcomes in patients with cardiac arrest is dependent on early resuscitation with the prioritization of interventions demonstrated to have survival benefit. When advanced notice is available, prepare the resuscitation area including airway equipment (with adjuncts to assist ventilation and waveform capnography devices). Adopt the leadership position and assign roles for chest compressions, airway support, application of monitor/defibrillator, and establishment of peripheral access.

High-quality chest compressions with minimal interruptions are the foundation of successful resuscitation – and guideline changes prioritizing compressions have demonstrated detectable improvements in rates of successful resuscitation9,10. Measurement of quantitative end-tidal capnography can guide adequacy of chest compressions11,12 and an abrupt increase may signal restoration of circulation without necessitating interruptions of chest compressions13,14. Sustained, low measures of end-tidal CO2 despite appropriate resuscitation may signal futility and (alongside other factors) guides termination of resuscitation11,12.

The next critical step in restoring circulation is prompt defibrillation of eligible rhythms (pVT/VF) when detected. The immediate delivery of 200J (uptitrated to the device maximum for subsequent shocks) of biphasic energy and restoration of a perfusing rhythm is one of few interventions with clear benefits. For pVT/VF that persists despite multiple countershocks (more than three), the addition of an intravenous antiarrhythmic appears to improve survival to hospital admission. The ARREST trial was a randomized controlled study comparing amiodarone to its diluent as placebo for OHCA with refractory pVT/VF showing significant improvement in survival to hospital admission for the amiodarone group15. This was followed by the ALIVE trial comparing amiodarone and lidocaine which showed significantly higher rates of survival to hospital admission in the amiodarone group16. However, a more recent randomized trial comparing amiodarone (in a novel diluent less likely to cause hypotension), lidocaine, and placebo in a similar patient population showed less convincing results, with no detected difference in survival or the secondary outcome of favorable neurological outcome for either amiodarone or lidocaine compared with placebo17. The heterogeneity of available data contributed to current guidelines which recommend that either amiodarone or lidocaine may be used for shock-refractory pVT/VF18.

Current guidelines also recommend the administration of vasopressors (epinephrine 1mg every 3-5 minutes). In one randomized controlled trial exploring the long-standing guideline recommendations, epinephrine was associated with increased rates of restoration of spontaneous circulation, though no significant impact on the primary outcome of survival to hospital discharge was identified19. Physiologically, increased systemic vascular resistance combined with positive beta-adrenergic impact on cardiac output would be expected to complement resuscitative efforts. However, more recent studies have suggested that arrest physiology and unanticipated pharmacologic effects may complicate this simplistic interpretation – particularly when patient-centered outcomes are emphasized. Research exploring the timing and amount of epinephrine suggest that earlier administration and higher cumulative doses are associated with negative impacts on survival to hospital discharge and favorable neurological outcomes20-22.

Ultimately, treatment should focus on optimal execution of measures with clear benefits (namely chest compressions and early defibrillation of eligible rhythms). Other management considerations with which the emergency physician is familiar with including establishing peripheral access and definitive airway management can be delayed.

Rapid Diagnostic Measures for the Identification of Reversible Processes

Traditional diagnostic measures are generally unavailable during an ongoing cardiac arrest resuscitation. The emergency medicine physician must rely on the physical examination and point-of-care tests with the objective of identifying potentially reversible processes. Measurement of capillary blood glucose can exclude hypoglycemia as a contributor. Point-of-care chemistry and blood gas analyzers can identify important electrolyte derangements, as well as clarifying the primary impulse in acid-base disturbances.

End-tidal capnography was discussed previously for the guidance of ongoing resuscitation, but it may have diagnostic utility in patients with SCD. In one study the initial EtCO2 was noted to be significantly higher for primary pulmonary processes (with PEA/asystole as presenting rhythm) compared to primary cardiac processes (with pVT/VF as presenting rhythm)23.

The use of point-of-care ultrasonography, particularly in PEA arrest where non-cardiac etiologies dominate, may help identify the etiology of arrest and direct therapy. Bedside ultrasonography should be directed first at assessment of cardiac function – examining the pericardial sac and gross abnormalities in chamber size. A pericardial effusion may suggest cardiac tamponade, ventricular collapse can be seen with hypovolemia, and asymmetric right-ventricular dilation points to pulmonary embolus where thrombolysis should be considered8. If cardiac ultrasound is unrevealing, thoracic ultrasound can identify pneumothorax24-27.

In the absence of ultrasonographic abnormalities, attention turns to other rapidly reversible precipitants first. If opioid toxicity is a consideration, an attempt at reversal with naloxone has few adverse effects. If any detected rhythm is a polymorphic ventricular tachycardia characteristic of torsades de pointes – rapid infusion of magnesium sulfate should follow defibrillation. Other potentially reversible medications or toxins should be managed as appropriate.

Post-Resuscitation Steps

After successful restoration of circulation, the next management steps are critical to the patient’s long-term outcomes. A definitive airway should be established if not already secured (and if restoration of circulation was not associated with neurological recovery sufficient for independent airway protection). Circulatory support should continue with fluid resuscitation and vasopressors to maintain end-organ perfusion.

An immediate ECG should be performed to identify infarction, ischemia or precipitants of dysrhythmia. ST-segment elevation after return of spontaneous circulation (ROSC) warrants emergent angiography and possible intervention. However, given the prevalence of cardiac causes (of which coronary disease is most common) for patients with pVT/VF arrest, the presence of ST elevations is likely of insufficient sensitivity to identify all patients who would benefit from angiography. Several studies and meta-analyses have explored a more inclusive selection strategy for angiography (patients without obvious non-cardiac causes for arrest), all of which identified survival benefits with angiography and successful angioplasty when possible28-30.

Finally, the induction of hypothermia (or targeted temperature management) has significant benefits in survivors of cardiac arrest and can be instituted in the emergency department. Studies first targeted a core temperature of 32-24°C, with a randomized controlled trial demonstrating higher rates of favorable neurological outcome and reduced mortality31. More recent studies suggest that a more liberal temperature target does not diffuse the positive effects of induced hypothermia. A randomized trial of 939 patients with OHCA comparing a targeted temperature of 33°C vs 36°C suggested that a lower temperature target did not confer higher benefit to mortality or recovery of neurological function32. The more liberal temperature target may alleviate adverse effects associated with hypothermia which include cardiovascular effects (bradycardia), electrolyte derangements (during induction and rewarming), and possible increased risk of infections33. Targeted temperature management is achieved with external cooling measures or infusion of cooled fluids, rarely requiring more invasive measures34. Aggregate review of available data in a recent meta-analysis further supports the use of targeted temperature management after cardiac arrest as standard-of-care35.

References

  1. Bergum D, Nordseth T, Mjølstad OC, Skogvoll E, Haugen BO. Causes of in-hospital cardiac arrest – Incidences and rate of recognition. Resuscitation. 2015;87:63-68. doi:10.1016/j.resuscitation.2014.11.007.
  2. Wallmuller C, Meron G, Kurkciyan I, Schober A, Stratil P, Sterz F. Causes of in-hospital cardiac arrest and influence on outcome. Resuscitation. 2012;83(10):1206-1211. doi:10.1016/j.resuscitation.2012.05.001.
  3. Vaartjes I, Hendrix A, Hertogh EM, et al. Sudden death in persons younger than 40 years of age: incidence and causes. European Journal of Cardiovascular Prevention & Rehabilitation. 2009;16(5):592-596. doi:10.1097/HJR.0b013e32832d555b.
  4. Zheng ZJ, Croft JB, Giles WH, Mensah GA. Sudden cardiac death in the United States, 1989 to 1998. Circulation. 2001;104(18):2158-2163.
  5. Hoes AW, Grobbee DE, Lubsen J, Man in ‘t Veld AJ, van der Does E, Hofman A. Diuretics, beta-blockers, and the risk for sudden cardiac death in hypertensive patients. Ann Intern Med. 1995;123(7):481-487.
  6. Siscovick DS, Raghunathan TE, Psaty BM, et al. Diuretic therapy for hypertension and the risk of primary cardiac arrest. N Engl J Med. 1994;330(26):1852-1857. doi:10.1056/NEJM199406303302603.
  7. Gettes LS. Electrolyte abnormalities underlying lethal and ventricular arrhythmias. Circulation. 1992;85(1 Suppl):I70-I76.
  8. Kürkciyan I, Meron G, Sterz F, et al. Pulmonary embolism as a cause of cardiac arrest: presentation and outcome. Arch Intern Med. 2000;160(10):1529-1535.
  9. Callaway CW, Soar J, Aibiki M, et al. Part 4: Advanced Life Support: 2015 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. In: Vol 132. American Heart Association, Inc.; 2015:S84-S145. doi:10.1161/CIR.0000000000000273.
  10. Kudenchuk PJ, Redshaw JD, Stubbs BA, et al. Impact of changes in resuscitation practice on survival and neurological outcome after out-of-hospital cardiac arrest resulting from nonshockable arrhythmias. Circulation. 2012;125(14):1787-1794. doi:10.1161/CIRCULATIONAHA.111.064873.
  11. Touma O, Davies M. The prognostic value of end tidal carbon dioxide during cardiac arrest: a systematic review. Resuscitation. 2013;84(11):1470-1479. doi:10.1016/j.resuscitation.2013.07.011.
  12. Levine RL, Wayne MA, Miller CC. End-tidal carbon dioxide and outcome of out-of-hospital cardiac arrest. N Engl J Med. 1997;337(5):301-306. doi:10.1056/NEJM199707313370503.
  13. Garnett AR, Ornato JP, Gonzalez ER, Johnson EB. End-tidal carbon dioxide monitoring during cardiopulmonary resuscitation. JAMA. 1987;257(4):512-515.
  14. Falk JL, Rackow EC, Weil MH. End-tidal carbon dioxide concentration during cardiopulmonary resuscitation. N Engl J Med. 1988;318(10):607-611. doi:10.1056/NEJM198803103181005.
  15. Kudenchuk PJ, Cobb LA, Copass MK, et al. Amiodarone for resuscitation after out-of-hospital cardiac arrest due to ventricular fibrillation. N Engl J Med. 1999;341(12):871-878. doi:10.1056/NEJM199909163411203.
  16. Dorian P, Cass D, Schwartz B, Cooper R, Gelaznikas R, Barr A. Amiodarone as compared with lidocaine for shock-resistant ventricular fibrillation. N Engl J Med. 2002;346(12):884-890. doi:10.1056/NEJMoa013029.
  17. Kudenchuk PJ, Brown SP, Daya M, et al. Amiodarone, Lidocaine, or Placebo in Out-of-Hospital Cardiac Arrest. N Engl J Med. 2016;374(18):1711-1722. doi:10.1056/NEJMoa1514204.
  18. Neumar RW, Shuster M, Callaway CW, et al. Part 1: Executive Summary: 2015 American Heart Association Guidelines Update for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. In: Vol 132. American Heart Association, Inc.; 2015:S315-S367. doi:10.1161/CIR.0000000000000252.
  19. Jacobs IG, Finn JC, Jelinek GA, Oxer HF, Thompson PL. Effect of adrenaline on survival in out-of-hospital cardiac arrest: A randomised double-blind placebo-controlled trial. Resuscitation. 2011;82(9):1138-1143. doi:10.1016/j.resuscitation.2011.06.029.
  20. Hagihara A, Hasegawa M, Abe T, Nagata T, Wakata Y, Miyazaki S. Prehospital epinephrine use and survival among patients with out-of-hospital cardiac arrest. JAMA. 2012;307(11):1161-1168. doi:10.1001/jama.2012.294.
  21. Dumas F, Bougouin W, Geri G, et al. Is epinephrine during cardiac arrest associated with worse outcomes in resuscitated patients? J Am Coll Cardiol. 2014;64(22):2360-2367. doi:10.1016/j.jacc.2014.09.036.
  22. Andersen LW, Kurth T, Chase M, et al. Early administration of epinephrine (adrenaline) in patients with cardiac arrest with initial shockable rhythm in hospital: propensity score matched analysis. BMJ. 2016;353:i1577. doi:10.1136/bmj.i1577.
  23. Grmec S, Lah K, Tusek-Bunc K. Difference in end-tidal CO2 between asphyxia cardiac arrest and ventricular fibrillation/pulseless ventricular tachycardia cardiac arrest in the prehospital setting. Crit Care. 2003;7(6):R139-R144. doi:10.1186/cc2369.
  24. Rose JS, Bair AE, Mandavia D, Kinser DJ. The UHP ultrasound protocol: a novel ultrasound approach to the empiric evaluation of the undifferentiated hypotensive patient. American Journal of Emergency Medicine. 2001;19(4):299-302. doi:10.1053/ajem.2001.24481.
  25. Hernandez C, Shuler K, Hannan H, Sonyika C, Likourezos A, Marshall J. C.A.U.S.E.: Cardiac arrest ultra-sound exam—A better approach to managing patients in primary non-arrhythmogenic cardiac arrest. Resuscitation. 2008;76(2):198-206. doi:10.1016/j.resuscitation.2007.06.033.
  26. Chardoli M, Heidari F, Shuang-ming S, et al. Echocardiography integrated ACLS protocol versus con- ventional cardiopulmonary resuscitation in patients with pulseless electrical activity cardiac arrest. Chinese Journal of Traumatology. 2012;15(5):284-287. doi:10.3760/cma.j.issn.1008-1275.2012.05.005.
  27. Zengin S, Yavuz E, Al B, et al. Benefits of cardiac sonography performed by a non-expert sonographer in patients with non-traumatic cardiopulmonary arrest. Resuscitation. 2016;102:105-109. doi:10.1016/j.resuscitation.2016.02.025.
  28. Spaulding CM, Joly LM, Rosenberg A, et al. Immediate coronary angiography in survivors of out-of-hospital cardiac arrest. N Engl J Med. 1997;336(23):1629-1633. doi:10.1056/NEJM199706053362302.
  29. Dumas F, Cariou A, Manzo-Silberman S, et al. Immediate Percutaneous Coronary Intervention Is Associated With Better Survival After Out-of-Hospital Cardiac Arrest: Insights From the PROCAT (Parisian Region Out of Hospital Cardiac Arrest) Registry. Circulation: Cardiovascular Interventions. 2010;3(3):200-207. doi:10.1161/CIRCINTERVENTIONS.109.913665.
  30. Millin MG, Comer AC, Nable JV, et al. Patients without ST elevation after return of spontaneous circulation may benefit from emergent percutaneous intervention: A systematic review and meta-analysis. Resuscitation. 2016;108:54-60. doi:10.1016/j.resuscitation.2016.09.004.
  31. Hypothermia after Cardiac Arrest Study Group. Mild therapeutic hypothermia to improve the neurologic outcome after cardiac arrest. N Engl J Med. 2002;346(8):549-556. doi:10.1056/NEJMoa012689.
  32. Nielsen N, Wetterslev J, Cronberg T, et al. Targeted Temperature Management at 33°C versus 36°C after Cardiac Arrest. N Engl J Med. 2013;369(23):2197-2206. doi:10.1056/NEJMoa1310519.
  33. Polderman KH, Peerdeman SM, Girbes AR. Hypophosphatemia and hypomagnesemia induced by cooling in patients with severe head injury. J Neurosurg. 2001;94(5):697-705. doi:10.3171/jns.2001.94.5.0697.
  34. Polderman KH, Herold I. Therapeutic hypothermia and controlled normothermia in the intensive care unit: Practical considerations, side effects, and cooling methods*. Critical Care Medicine. 2009;37(3):1101-1120. doi:10.1097/CCM.0b013e3181962ad5.
  35. Schenone AL, Cohen A, Patarroyo G, et al. Therapeutic hypothermia after cardiac arrest: A systematic review/meta-analysis exploring the impact of expanded criteria and targeted temperature. Resuscitation. 2016;108:102-110. doi:10.1016/j.resuscitation.2016.07.238.

Atrial Fibrillation

A 64-year-old male with a history of hypertension and hyperlipidemia presents with palpitations. He reports intermittent symptoms over the past 3 days, associated with dyspnea on exertion, but no chest pain, dizziness or syncope. His vital signs are notable for tachycardia (HR 129bpm) without hypotension or hypoxia. An ECG shows atrial fibrillation with rapid ventricular response.

Evaluation and Management

While the patient’s tachyarrhythmia is not yet associated with hypotension or evidence of malperfusion, preparation is key and includes continuous telemetry and vital sign monitoring, establishment of intravenous access, and application of cardioversion pads 1.

The presence of atrial fibrillation is new and the rapid ventricular response (RVR) may be symptomatic of more serious and potentially reversible pathology. A thorough history and physical examination may elucidate a precipitant and should precede attempts at rate- or rhythm-control. RVR may be provoked by any of the processes that would otherwise induce a sinus tachycardia, including bleeding, infection, toxic/metabolic etiologies and endocrinopathies 2, 3

Candidacy for Cardioversion

In hemodynamically stable patients with new-onset atrial fibrillation, candidacy for cardioversion includes:4-6

  • Stable without ischemia, hypotension or acute CHF
  • Clear onset of <48 hours
  • Non-severe symptoms
  • Few prior episodes/treatments
  • Existing anti-coagulation with warfarin and therapeutic INR (at least 3 weeks)
  • Absence of high-risk features: rheumatic/valvular disease, severe left-ventricular dysfunction, prosthetic valves, or history of thromboembolism

Cardioversion may be pharmacologic (with procainamide, or amiodarone), or electrical (synchronized at 100-200J). Electrical cardioversion for acute atrial fibrillation is both more effective and results in shorter lengths-of-stay in the emergency department – though stable patients should participate in shared decision-making7. Another important consideration when cardioversion is pursued is the prevention of systemic embolization. While atrial fibrillation of duration less than 48-hours is rarely associated with systemic embolization, certain populations are at higher risk8. One retrospective study of 3143 patients with atrial fibrillation for less than 48-hours demonstrated an overall risk of 0.7% for thromboembolic events – though the rate was significantly higher in patients older than 60 years or with other comorbidities (heart failure, diabetes)9. The risk of embolic events should be weighed against the risk of bleeding.

CHA2DS2VASc10-12

C Congestive Heart Failure 1
H Hypertension 1
A2 Age >75 2
D Diabetes Mellitus 1
S2 Stroke, TIA, Thromboembolism 2
V Vascular disease 1
A Age >65 1
Sc Sex Category Female 1

 

  • 0: low risk (may not require anti-coagulation)
  • 1: low-moderate risk (consider anti-platelet or anti-coagulation)
  • ≥ 2: moderate-high risk (anti-coagulation recommended)

HAS-BLED13,14

H Uncontrolled hypertension 1
A Abnormal renal/liver function
Renal (renal replacement therapy, creatinine >2.3mg/dL) 1
Liver (cirrhosis, bilirubin >2x, AST/ALT >3x) 1
S Stroke 1
B Bleeding history/anemia 1
L Labile INR 1
E Elderly (>65) 1
D Drugs
Anti-platelet agent, NSAID 1
Alcohol (>8 drinks/week) 1

 

  • 0: low risk (0.6-1.13% annual risk of major bleeding)
  • 1-2: intermediate risk (1.02-3.2% annual risk of major bleeding)
  • ≥ 3: high risk (4.9-19.6% annual risk of major bleeding)

Pharmacologic Management

For patients who are not candidates for cardioversion, rate-control should be pursued. Options include AV nodal blocking agents such as calcium channel blockers and beta-blockers15. The most frequently studied agents of each category are metoprolol and diltiazem. Both classes show comparable efficacy and safety profiles with trends favoring diltiazem16, 17.

Algorithm for the management of atrial fibrillation with rapid ventricular response:

Algorithm for the management of atrial fibrillation with rapid ventricular response

References

  1. Atzema, C.L. and T.W. Barrett, Managing atrial fibrillation. Ann Emerg Med, 2015. 65(5): p. 532-9.
  2. January, C.T., et al., 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation: Executive Summary. A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the Heart Rhythm Society, 2014. 64(21): p. 2246-2280.
  3. Scheuermeyer, F.X., et al., Emergency Department Patients With Atrial Fibrillation or Flutter and an Acute Underlying Medical Illness May Not Benefit From Attempts to Control Rate or Rhythm. Ann Emerg Med, 2015. 65(5): p. 511-522 e2.
  4. Stiell, I.G., et al., Association of the Ottawa Aggressive Protocol with rapid discharge of emergency department patients with recent-onset atrial fibrillation or flutter. CJEM, 2010. 12(3): p. 181-91.
  5. von Besser, K. and A.M. Mills, Is discharge to home after emergency department cardioversion safe for the treatment of recent-onset atrial fibrillation? Ann Emerg Med, 2011. 58(6): p. 517-20.
  6. Cohn, B.G., S.M. Keim, and D.M. Yealy, Is emergency department cardioversion of recent-onset atrial fibrillation safe and effective? J Emerg Med, 2013. 45(1): p. 117-27.
  7. Bellone, A., et al., Cardioversion of acute atrial fibrillation in the emergency department: a prospective randomised trial. Emerg Med J, 2012. 29(3): p. 188-91.
  8. Weigner, M.J., et al., Risk for clinical thromboembolism associated with conversion to sinus rhythm in patients with atrial fibrillation lasting less than 48 hours. Ann Intern Med, 1997. 126(8): p. 615-20.
  9. Airaksinen, K.E., et al., Thromboembolic complications after cardioversion of acute atrial fibrillation: the FinCV (Finnish CardioVersion) study. J Am Coll Cardiol, 2013. 62(13): p. 1187-92.
  10. Friberg, L., M. Rosenqvist, and G.Y. Lip, Evaluation of risk stratification schemes for ischaemic stroke and bleeding in 182 678 patients with atrial fibrillation: the Swedish Atrial Fibrillation cohort study. Eur Heart J, 2012. 33(12): p. 1500-10.
  11. Lip, G.Y., et al., Refining clinical risk stratification for predicting stroke and thromboembolism in atrial fibrillation using a novel risk factor-based approach: the euro heart survey on atrial fibrillation. Chest, 2010. 137(2): p. 263-72.
  12. Ntaios, G., et al., CHADS(2), CHA(2)S(2)DS(2)-VASc, and long-term stroke outcome in patients without atrial fibrillation. Neurology, 2013. 80(11): p. 1009-17.
  13. Lip, G.Y., et al., Comparative validation of a novel risk score for predicting bleeding risk in anticoagulated patients with atrial fibrillation: the HAS-BLED (Hypertension, Abnormal Renal/Liver Function, Stroke, Bleeding History or Predisposition, Labile INR, Elderly, Drugs/Alcohol Concomitantly) score. J Am Coll Cardiol, 2011. 57(2): p. 173-80.
  14. Pisters, R., et al., A novel user-friendly score (HAS-BLED) to assess 1-year risk of major bleeding in patients with atrial fibrillation: the Euro Heart Survey. Chest, 2010. 138(5): p. 1093-100.
  15. Goralnick, E. and L.J. Bontempo, Atrial Fibrillation. Emerg Med Clin North Am, 2015. 33(3): p. 597-612.
  16. Demircan, C., et al., Comparison of the effectiveness of intravenous diltiazem and metoprolol in the management of rapid ventricular rate in atrial fibrillation. Emerg Med J, 2005. 22(6): p. 411-4.
  17. Fromm, C., et al., Diltiazem vs. Metoprolol in the Management of Atrial Fibrillation or Flutter with Rapid Ventricular Rate in the Emergency Department. J Emerg Med, 2015. 49(2): p. 175-82.
  18. DiMarco, J.P., Atrial fibrillation and acute decompensated heart failure. Circ Heart Fail, 2009. 2(1): p. 72-3.

Blunt Cardiac Injury

Case Presentation

A 35-year-old female with no past medical history is brought in by ambulance to the emergency department. She was struck by a firework (“Roman Candle”) which lodged in her mid-chest until the propellant was consumed. She transiently lost consciousness but was awake upon EMS arrival. She complains of pleuritic chest pain. Examination reveals a circular 4x4cm full-thickness burn to the mid-chest with surrounding deep and superficial partial-thickness burns. Her ECG shows normal sinus rhythm, the initial serum troponin I is 32.9 (normal <0.012). CT angiography of the thorax is obtained.

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Mechanisms

Blunt cardiac injury (BCI) may be induced by multiple forces including direct thoracic trauma, crush injury of mediastinal contents between the sternum and thoracic spine, rapid deceleration causing tears at venous-atrial confluences, abrupt pressure changes from rapid compression of abdominal contents, blast injury, or laceration from bone fracture fragments1. The most common mechanisms of injury are motor vehicle collisions (50%), auto versus pedestrian (35%), motorcycle accidents (9%) and falls from significant height (>6m)2.

BCI represents a spectrum of conditions. Diagnosis is both challenging and critical as clinical manifestations can be absent or rapidly fatal.

At one end of the spectrum is myocardial contusion. The lack of a gold-standard for the diagnosis of this clinical entity has led to a preference for describing associated abnormalities if present3,4, including cardiac dysfunction (identified on echocardiography) or the next entity along the spectrum – arrhythmia.

The most common arrhythmia identified in blunt cardiac injury is sinus tachycardia, followed by premature atrial or ventricular contractions, T-wave changes, and atrial fibrillation or flutter5. Commotio cordis is a unique arrhythmia induced by untimely precordial impact (often in sports) during a vulnerable phase of ventricular excitability, resulting in ventricular fibrillation2.

ST-segment elevations after blunt cardiac injury should raise concern for myocardial infarction due to coronary artery dissection, laceration or thrombosis (often in already-diseased vessels) 5,6.

The remaining disease entities are increasingly rare, require careful examination or imaging for diagnosis, and are more likely to be non-survivable. Septal injury can range from small tears to rupture. Valvular injury most commonly affects the aortic valve (followed by mitral and tricuspid valves) and involves damage to leaflets, or rupture of papillary muscles or chordae tendineae. The clinical presentation is of acute valvular insufficiency, including acute heart failure and murmur2,7,8. A widened pulse pressure may be noted with aortic valve injury, and the manifestations of valvular injury may be delayed9. Finally, myocardial wall rupture is unlikely to be survivable, though patients may present with cardiac tamponade if rupture is small or contained2.

Evaluation

The primary diagnostic modalities for the assessment of BCI in the emergency department include assessment for pericardial fluid during the Focused Assessment with Sonography for Trauma (FAST), electrocardiography and cardiac enzymes.

While specific for identifying patients at risk of complications of BCI, electrocardiography alone is not sufficient to exclude BCI. In one study, only 59% of patient with echocardiographic evidence of BCI (wall-motion abnormalities, other chamber abnormalities) had initially abnormal ECG’s10. In another study, 41% of patients with initially normal ECG’s developed clinically significant abnormalities11. The use of specialized electrocardiography including right-sided ECG (proposed to better detect right-ventricular abnormalities which are more commonly associated with BCI) and signal-averaged ECG is not supported11,12.

Several studies have supported the use of serum troponin for the detection of clinically significant BCI – particularly in combination with electrocardiography. A prospective study in 2001 evaluating patients with blunt thoracic trauma using ECG at admission and 8-hours, as well as troponin I at admission, 4- and 8-hours had a negative predictive value of 100% for significant BCI (arrhythmia requiring treatment, shock, or structural cardiac abnormalities) in patients with initially normal ECG and troponin13.

Another prospective study adding to the population evaluated by Salim et al. included 41 patients with normal ECG’s and troponin levels at admission and 8-hours who were admitted for significant mechanisms, none developed significant BCI (again described as arrhythmia requiring treatment, shock, or structural cardiac abnormalities) after 1 to 3 days of observation14. The precise timing of serum troponin analysis remains unclear.

While FAST may detect hemopericardium warranting immediate intervention, formal echocardiography is indicated for patients with unexplained hypotension (to evaluate for valvular injury or regional wall-motion abnormalities) or persistent arrhythmias (to evaluate for arrhythmogenic intramural hematomas)15. The presence of sternal fractures was previously thought to increase risk of BCI and mandate echocardiography, however this notion is no longer supported16-18. The role of advanced imaging including helical CT (cardiac-gated), and MRI remains unclear19.

Algorithm for the Evaluation of Blunt Thoracic Trauma

Notes:
† Arrest in ED, immediate chest tube output >20ml/kg (>1.5L) or >200mL/hr for 2-4hr.

Management

Management of BCI depends on the pathologic process localized along the spectrum defined above. Persistent hypotension after appropriate evaluation for alternative etiologies may represent myocardial contusion with cardiac dysfunction and should be evaluated with echocardiography. Similarly, echocardiography and observation with continuous telemetry monitoring is indicated for any new arrhythmia or persistent and unexplained tachycardia. Patients with only elevation of the serum troponin without electrocardiographic abnormalities or obvious cardiac dysfunction should also be admitted for observation and serial cardiac enzymes. Traumatic myocardial infarction, valvular injury, or post-traumatic structural myocardial defects should be managed in consultation with cardiothoracic surgery5,19-21.

Case Conclusion

The CT interpretation noted the soft-tissue defect identified on examination as well as associated pulmonary contusions and a non-displaced sternal fracture. The patient went to the operating room for washout and debridement. A transthoracic echocardiogram demonstrated trace mitral regurgitation and a small pericardial effusion. She remained hemodynamically stable and serial troponin measures downtrended – no dysrhythmias were noted on telemetry monitoring. She was discharged on hospital day four with a negative-pressure wound dressing.

References

  1. Schultz JM, Trunkey DD. Blunt cardiac injury. Crit Care Clin. 2004;20(1):57-70.
  2. Yousef R, Carr JA. Blunt cardiac trauma: a review of the current knowledge and management. Ann Thorac Surg. 2014;98(3):1134-1140. doi:10.1016/j.athoracsur.2014.04.043.
  3. Mattox KL, Flint LM, Carrico CJ, et al. Blunt cardiac injury. The Journal of Trauma: Injury, Infection, and Critical Care. 1992;33(5):649-650.
  4. Sybrandy KC, Cramer MJM, Burgersdijk C. Diagnosing cardiac contusion: old wisdom and new insights. Heart. 2003;89(5):485-489.
  5. Elie M-C. Blunt cardiac injury. Mt Sinai J Med. 2006;73(2):542-552.
  6. Edouard AR, Felten M-L, Hebert J-L, Cosson C, Martin L, Benhamou D. Incidence and significance of cardiac troponin I release in severe trauma patients. Anesthesiology. 2004;101(6):1262-1268.
  7. Cordovil A, Fischer CH, Rodrigues ACT, et al. Papillary Muscle Rupture After Blunt Chest Trauma. Journal of the American Society of Echocardiography. 2006;19(4):469.e1-469.e3. doi:10.1016/j.echo.2005.12.005.
  8. Pasquier M, Sierro C, Yersin B, Delay D, Carron P-N. Traumatic Mitral Valve Injury After Blunt Chest Trauma: A Case Report and Review of the Literature. The Journal of Trauma: Injury, Infection, and Critical Care. 2010;68(1):243-246. doi:10.1097/TA.0b013e3181bb881e.
  9. Ismailov RM, Weiss HB, Ness RB, Lawrence BA, Miller TR. Blunt cardiac injury associated with cardiac valve insufficiency: trauma links to chronic disease? Injury. 2005;36(9):1022-1028. doi:10.1016/j.injury.2005.05.028.
  10. García-Fernández MA, López-Pérez JM, Pérez-Castellano N, et al. Role of transesophageal echocardiography in the assessment of patients with blunt chest trauma: correlation of echocardiographic findings with the electrocardiogram and creatine kinase monoclonal antibody measurements. Am Heart J. 1998;135(3):476-481.
  11. Fulda GJ, Giberson F, Hailstone D, Law A, Stillabower M. An evaluation of serum troponin T and signal-averaged electrocardiography in predicting electrocardiographic abnormalities after blunt chest trauma. The Journal of Trauma: Injury, Infection, and Critical Care. 1997;43(2):304–10–discussion310–2.
  12. Walsh P, Marks G, Aranguri C, et al. Use of V4R in patients who sustain blunt chest trauma. The Journal of Trauma: Injury, Infection, and Critical Care. 2001;51(1):60-63.
  13. Salim A, Velmahos GC, Jindal A, et al. Clinically significant blunt cardiac trauma: role of serum troponin levels combined with electrocardiographic findings. The Journal of Trauma: Injury, Infection, and Critical Care. 2001;50(2):237-243.
  14. Velmahos GC, Karaiskakis M, Salim A, et al. Normal electrocardiography and serum troponin I levels preclude the presence of clinically significant blunt cardiac injury. The Journal of Trauma: Injury, Infection, and Critical Care. 2003;54(1):45–50–discussion50–1. doi:10.1097/01.TA.0000046315.73441.D8.
  15. Nagy KK, Krosner SM, Roberts RR, Joseph KT, Smith RF, Barrett J. Determining which patients require evaluation for blunt cardiac injury following blunt chest trauma. World J Surg. 2001;25(1):108-111.
  16. Roy-Shapira A, Levi I, Khoda J. Sternal fractures: a red flag or a red herring? The Journal of Trauma: Injury, Infection, and Critical Care. 1994;37(1):59-61.
  17. Hills MW, Delprado AM, Deane SA. Sternal fractures: associated injuries and management. The Journal of Trauma: Injury, Infection, and Critical Care. 1993;35(1):55-60.
  18. Rashid MA, Ortenwall P, Wikström T. Cardiovascular injuries associated with sternal fractures. Eur J Surg. 2001;167(4):243-248. doi:10.1080/110241501300091345.
  19. Clancy K, Velopulos C, Bilaniuk JW, et al. Screening for blunt cardiac injury: an Eastern Association for the Surgery of Trauma practice management guideline. J Trauma Acute Care Surg. 2012;73(5 Suppl 4):S301-S306. doi:10.1097/TA.0b013e318270193a.
  20. El-Menyar A, Thani Al H, Zarour A, Latifi R. Understanding traumatic blunt cardiac injury. Ann Card Anaesth. 2012;15(4):287-295. doi:10.4103/0971-9784.101875.
  21. Hockberger RS, Walls RM. Rosen’s Emergency Medicine. Mosby Incorporated; 2002.

Arterial Pressure Indices

Indications

  • Assess for peripheral arterial disease (PAD)
  • Assess for risk of arterial injury in trauma

Test characteristics

  • PAD: ABI <0.90 sensitivity 95%, specificity 100% for >50% stenosis on arteriography1
  • Trauma: API <0.90 sensitivity 95%, specificity 97% for major arterial injury2

Technique for obtaining arterial pressure indices3

  1. Patient lies supine with extremities at level of the heart for 10 minutes
  2. Ankle: cuff positioned just above malleolus
  3. Brachial: cuff positioned just above antecubital fossa
  4. Doppler SBP
  5. Sequence: first arm, first PT, first DP, other PT, other DP, other arm. If SBP of first arm >10mmHg compared to second arm, repeat first arm and disregard first measure
  6. Calculation: ABI = higher of DP or PT / higher arm

Interpretation of ABI for PAD3

Value Interpretation
0-0.40 Severe PAD, rest pain, gangrene
0.41-0.90 PAD, claudication
0.91-1.30 Normal
>1.30 Non-compressible, severely calcified

Algorithm for the Evaluation of Arterial Injury4, 5

Algorithm for the Evaluation of Arterial Injury

Notes:

  • † If unable to palpate pulses due to patient habitus or shock/hypothermia, reattempt with oversized cuff and after appropriate rewarming/resuscitation. If remains challenging, proceed with imaging.
  • ‡ Proximal LE arterial injuries refers to the major named arteries of the thigh (excluding the profunda femoris) and proximal to the anterior tibial artery and tibioperoneal bifurcation.

Arteries of the Lower Leg

References:

  1. Mohler ER. Peripheral arterial disease: identification and implications. Arch Intern Med. 2003;163(19):2306-2314. doi:10.1001/archinte.163.19.2306.
  2. Johansen K, Lynch K, Paun M, Copass M. Non-invasive vascular tests reliably exclude occult arterial trauma in injured extremities. The Journal of Trauma: Injury, Infection, and Critical Care. 1991;31(4):515–9–discussion519–22.
  3. Aboyans V, Criqui MH, Abraham P, et al. Measurement and interpretation of the ankle-brachial index: a scientific statement from the American Heart Association. Circulation. 2012;126(24):2890-2909. doi:10.1161/CIR.0b013e318276fbcb.
  4. Feliciano DV, Moore FA, Moore EE, et al. Evaluation and management of peripheral vascular injury. Part 1. Western Trauma Association/critical decisions in trauma. J Trauma. 2011;70(6):1551-1556. doi:10.1097/TA.0b013e31821b5bdd.
  5. Fox N, Rajani RR, Bokhari F, et al. Evaluation and management of penetrating lower extremity arterial trauma: an Eastern Association for the Surgery of Trauma practice management guideline. J Trauma Acute Care Surg. 2012;73(5 Suppl 4):S315-S320. doi:10.1097/TA.0b013e31827018e4.
  6. Inaba K, Branco BC, Reddy S, et al. Prospective evaluation of multidetector computed tomography for extremity vascular trauma. J Trauma. 2011;70(4):808-815. doi:10.1097/TA.0b013e3182118384.

Weakness

A systematic approach to motor weakness progresses along an anatomic tract from the cerebral cortex to individual sarcomeres. Impulses are generated in the primary motor cortex mapped to the homunculus, then aggregate as they descend through the internal capsule. Fibers decussate in the medulla and descend in the contralateral lateral corticospinal tract. These upper motor neurons (UMN) synapse with the lower motor neuron (LMN) in the anterior horn of the spinal cord. The lower motor neuron is bundled with neighboring fibers into a peripheral nerve and activates the target muscle fibers at the neuromuscular junction.

Algorithm for the Evaluation of Weakness

Algorithm for the Evaluation of Weakness

Upper Versus Lower Motor Neuron Findings

Finding Upper Lower
Reflexes
Atrophy
Weakness
Fasciculation
Tone
Summary
Recalling these findings can be simplified by understanding the underlying process. Denervation near the target muscle fibers (lower motor neuron disease) results in dampening of the efferent limb of spinal reflexes, resulting in hyporeflexia. The absence of nourishing stimulation leads to muscle atrophy and disorganized interpretation of proximal activity produces fasciculation.

Comparison Between Myopathy, Neuropathy and Neuromuscular Junction Processes

Finding Myopathy Neuropathy Neuromuscular Junction
Example Polymyositis Guillain-Barre Syndrome Myasthenia Gravis
Distribution Proximal > Distal Distal > Proximal Diffuse, Bulbar
Reflexes Normal
Sensory
Fatigue
CK Normal Normal

Motor Strength Grading

Grade Description
5 Normal
4 Reduced, moves against resistance
3 Moves against gravity
2 Moves only with elimination of gravity
1 Fasciculation only
0 None

Reflex Grading

Grade Description
4 Increased amplitude, spread to adjacent, clonus
3 Increased
2 Normal
1 Decreased
0 None

References

  1. Ganti L, Rastogi V. Acute Generalized Weakness. Emerg Med Clin North Am. 2016;34(4):795-809. doi:10.1016/j.emc.2016.06.006.
  2. Asimos AW. Weakness: A Systematic Approach To Acute, Non-traumatic, Neurologic And Neuromuscular Causes. Emergency Medicine Practice. 2002;4(12):1-28.
  3. Morchi R. Weakness. In: Rosen’s Emergency Medicine. Elsevier Inc.; 2014:2521.