Febrile Seizure

Brief HPI:

An 8-month old female, fully-immunized, otherwise healthy is brought in by paramedics after 1 minute of witnessed generalized tonic-clonic shaking. The patient had otherwise been well, eating and behaving normally earlier that day. On EMS arrival, the patient was post-ictal but grew increasingly responsive en-route and upon presentation to the pediatric emergency department she was crying and appeared normal to her parents. Capillary glucose was 118g/dL. On examination the patient was noted to be febrile with a rectal temperature of 39.4°C. The remainder of the physical examination was normal.

ED Course:

The patient received anti-pyretics and a urinalysis was obtained which was not suggestive of urinary tract infection. During the 3-hour period of observation in the emergency department the patient remained at her normal baseline, had no further seizure activity, and tolerated oral intake with difficulty. The patient was suspected to have a simple febrile seizure and was discharged home.

Algorithm for the Diagnosis of Febrile Seizure

Algorithm for the Evaluation of Febrile Seizure

References

  1. Syndi Seinfeld DO, Pellock JM. Recent Research on Febrile Seizures: A Review. J Neurol Neurophysiol. 2013;4(165). doi:10.4172/2155-9562.1000165.
  2. Whelan H, Harmelink M, Chou E, et al. Complex febrile seizures-A systematic review. Dis Mon. 2017;63(1):5-23. doi:10.1016/j.disamonth.2016.12.001.
  3. Millichap JJ, Gordon Millichap J. Methods of investigation and management of infections causing febrile seizures. Pediatr Neurol. 2008;39(6):381-386. doi:10.1016/j.pediatrneurol.2008.07.017.
  4. Subcommittee on Febrile Seizures, American Academy of Pediatrics. Neurodiagnostic evaluation of the child with a simple febrile seizure. Pediatrics. 2011;127(2):389-394. doi:10.1542/peds.2010-3318.

Leukemoid Reaction

Brief HPI:

An approximately 80-year-old male with unknown medical history is brought to the emergency department from a skilled nursing facility after unwitnessed arrest – EMS providers established return of spontaneous circulation after chest compressions and epinephrine. On arrival, the patient was hypotensive (MAP 40mmHg) and hypoxic (SpO2 85%) with mask ventilation. The patient was intubated, resuscitated with intravenous fluids and started on vasopressors. Imaging demonstrated lung consolidation consistent with multifocal pneumonia versus aspiration. Laboratory studies were obtained:

  • CBC: WBC: 49.2 (N: 64%, Bands: 20%)
  • ABG: pH: 7.07, pCO2: 73mmHg
  • Lactate: 9.1mmol/L
leukemoid_ct_01
leukemoid_ct_01
leukemoid_ct_02
leukemoid_ct_02
leukemoid_ct_03
leukemoid_ct_03
leukemoid_ct_04
leukemoid_ct_04
leukemoid_ct_05
leukemoid_ct_05
leukemoid_ct_06
leukemoid_ct_06
leukemoid_ct_07
leukemoid_ct_07
leukemoid_ct_08
leukemoid_ct_08
leukemoid_ct_09
leukemoid_ct_09
leukemoid_ct_10
leukemoid_ct_10
leukemoid_ct_11
leukemoid_ct_11
leukemoid_ct_12
leukemoid_ct_12

CT Pulmonary Angiography

Peribronchial opacities and patchy consolidation in the lungs which may represent multifocal pneumonia and/or aspiration in the appropriate clinical setting.
Mildly dilated main pulmonary artery suggestive of pulmonary arterial hypertension.

ED Course:

The patient was admitted to the medical intensive care unit for cardiopulmonary arrest presumed secondary to hypoxia and septic shock from healthcare-associated pneumonia or aspiration. The markedly elevated white blood cell count was attributed to a combination of infection and tissue ischemia from transient global hypoperfusion.


Definition: 1

  • Markedly elevated leukocyte (particularly neutrophil) count without hematologic malignancy
  • Cutoff is variable, 25-50k

Review of Available Literature

Retrospective review of 135 patients with WBC >25k 2
48% infection
15% malignancy
9% hemorrhage
12% glucocorticoid or granulocyte colony stimulating therapy
Retrospective review of 173 patients with WBC >30k 3
48% infection (7% C. difficile)
28% tissue ischemia
7% obstetric process (vaginal or cesarean delivery)
5% malignancy
Observational study of 54 patients with WBC >25k 4
Consecutive patients presenting to the emergency department
Compared to age-matched controls with moderate leukocytosis (12-24k)
Patients with leukemoid reaction were more likely to have an infection, be hospitalized and die.

Differential Diagnosis of Leukemoid Reaction 1,5-8

Differential Diagnosis of Leukemoid Reaction

References

  1. Sakka V, Tsiodras S, Giamarellos-Bourboulis EJ, Giamarellou H. An update on the etiology and diagnostic evaluation of a leukemoid reaction. Eur J Intern Med. 2006;17(6):394-398. doi:10.1016/j.ejim.2006.04.004.
  2. Reding MT, Hibbs JR, Morrison VA, Swaim WR, Filice GA. Diagnosis and outcome of 100 consecutive patients with extreme granulocytic leukocytosis. Am J Med. 1998;104(1):12-16.
  3. Potasman I, Grupper M. Leukemoid reaction: spectrum and prognosis of 173 adult patients. Clin Infect Dis. 2013;57(11):e177-e181. doi:10.1093/cid/cit562.
  4. Lawrence YR, Raveh D, Rudensky B, Munter G. Extreme leukocytosis in the emergency department. QJM. 2007;100(4):217-223. doi:10.1093/qjmed/hcm006.
  5. Marinella MA, Burdette SD, Bedimo R, Markert RJ. Leukemoid reactions complicating colitis due to Clostridium difficile. South Med J. 2004;97(10):959-963. doi:10.1097/01.SMJ.0000054537.20978.D4.
  6. Okun DB, Tanaka KR. Profound leukemoid reaction in cytomegalovirus mononucleosis. JAMA. 1978;240(17):1888-1889.
  7. Halkes CJM, Dijstelbloem HM, Eelkman Rooda SJ, Kramer MHH. Extreme leucocytosis: not always leukaemia. Neth J Med. 2007;65(7):248-251.
  8. Granger JM, Kontoyiannis DP. Etiology and outcome of extreme leukocytosis in 758 nonhematologic cancer patients: a retrospective, single-institution study. Cancer. 2009;115(17):3919-3923. doi:10.1002/cncr.24480.

Thrombocytopenia

Brief HPI:

A middle-aged female with no known medical history is brought to the emergency department with altered mental status. Her family notes worsening confusion over the past 2-3 days associated with vomiting and yellow discoloration of skin and eyes.

Initial vital signs were normal, though with borderline hypotension (99/64mmHg). Examination demonstrated an alert, but lethargic patient with jaundice and scleral icterus, no skin lesions were appreciated. Laboratory studies were obtained:

CBC

  • WBC: 21.3 (N: 83%, Bands: 11%)
  • Hb: 5.5
  • Plt: 6k
  • Marked schistocytes

Coagulation Panel

  • INR: 1.26
  • PTT: Normal
  • Fibrinogen: Normal
  • FDP: Normal
  • D-dimer: >9,000 (normal 250)
  • Haptoglobin: Undetectable
  • LDH: 1493

CMP

  • Creatinine: 1.1
  • AST/ALT: Normal
  • TB: 4.3, DB: 0.8

Imaging:

CT Head: No acute intracranial process.

ttp_ct_01
ttp_ct_01
ttp_ct_02
ttp_ct_02
ttp_ct_03
ttp_ct_03
ttp_ct_04
ttp_ct_04
ttp_ct_05
ttp_ct_05
ttp_ct_06
ttp_ct_06
ttp_ct_07
ttp_ct_07
ttp_ct_08
ttp_ct_08
ttp_ct_09
ttp_ct_09
ttp_ct_10
ttp_ct_10
ttp_ct_11
ttp_ct_11
ttp_ct_12
ttp_ct_12
ttp_ct_13
ttp_ct_13
ttp_ct_14
ttp_ct_14
ttp_ct_15
ttp_ct_15
ttp_ct_16
ttp_ct_16
ttp_ct_17
ttp_ct_17
ttp_ct_18
ttp_ct_18
ttp_ct_19
ttp_ct_19

CT Abdomen/Pelvis with Contrast

Moderate free intra-abdominal fluid, heterogeneous liver with periportal edema, dense right middle lobe consolidation.

ED Course:

The patient developed worsening respiratory failure with hypoxia and tachypnea requiring endotracheal intubation. Thrombotic thrombocytopenic purpura was suspected and while awaiting emergent plasma exchange transfusion, the patient arrested and resuscitation efforts were unsuccessful.

The patient’s ADAMTS13 activity level was <3%. Autopsy demonstrated consolidation of the right middle lobe with possible lymphoproliferative mass, and lung petechial hemorrhages from microvascular thrombi.

Differential Diagnosis of Thrombocytopenia 1-7

Differential Diagnosis of Thrombocytopenia

Algorithm for the Evaluation of Thrombocytopenia 8

Algorithm for the Evaluation of Thrombocytopenia

Definition 9

  • Mild: <150k
  • Moderate: 100-150k
  • Severe: <50k
    • 10-30k: bleeding with minimal trauma
    • <10k: increased risk spontaneous bleeding

History 9,10

  • Prior platelet count
  • Family history bleeding disorders
  • Medications
    • Heparin
    • Quinine, quinidine
    • Rifampin
    • Trimethoprim-sulfamethoxazole
    • Vancomycin
  • Alcohol use
  • Travel-related infections

Physical Examination 9,10

  • Splenomegaly (liver disease)
  • Lymphadenopathy (infection, malignancy)

Workup 10,11

Schistocytes

Red blood cell fragments (schistocytes) 11

  • hCG
  • Repeat CBC
    • Detect spurious measure
    • Neutrophil-predominant leukocytosis: bacterial infection
    • Immature leukocytes (blasts): leukemia, myelodysplasia
  • Peripheral smear
    • Schistocytes: microangiopathic process (DIC, TTP, HUS)
    • Atypical lymphocytes: viral infection
    • Intracellular parasites: malaria
    • Hypersegmented neutrophils: nutritional deficiency
  • Infectious features: HIV, HCV, EBV, H.pylori, blood cultures
  • Autoimmune features: ANA, APL-Ab
  • Suspected occult liver disease: LFT, PT/PTT/INR
  • Suspected thrombotic microangiopathy: PT/PTT/INR, haptoglobin, LDH, fibrinogen, FDP, d-dimer

Specific Conditions 2-6,9,12-20

Disease Cause Presentation Laboratory Findings Treatment
DIC Sepsis
Trauma
Burn
Malignancy
Bleeding
Multi-organ failure
Shock
INR
Fibrinogen
FDP
D-dimer
Directed at underlying cause
Transfusion thresholds for hemorrhage:
FFP for INR >1.5
Platelets if <50k
Cryoprecipitate of fibrinogen <100mg/dL
TTP Insufficient ADAMTS-13 activity Non-specific constitutional symptoms (ex. weakness)
Neuro: headache, AMS, focal neuro deficit
GI: abdominal pain, nausea/vomiting
LDH
Reticulocyte
Unconjugated bilirubin
Haptoglobin
Plasma exchange
HUS Shiga-toxin-producing bacteria, E. coli O157:H7 Bloody diarrhea, anuria, oliguria, and hypertension Aggressive supportive care
HELLP Spectrum of eclampsia Hypertension
Visual symptoms
Headache
RUQ abdominal pain
AST/ALT
Uric acid
Unconjugated bilirubin
LDH
Reticulocyte
Haptoglobin
Delivery, MgSO4
ITP Primary ITP

Secondary ITP
– Drug
– Autoimmune
– Infection
– Malignancy

Usually asymptomatic, may have petechiae or easy bruising Isolated thrombocytopenia Steroids
HIT Exposure to heparin or LMWH Thrombocytopenia or a 50 percent reduction in platelet count between 5-10d exposure
New thrombosis or skin necrosis
4 T’s score
Platelet factor 4 antibodies Withdraw heparin

References

  1. Greinacher A, Selleng S. How I evaluate and treat thrombocytopenia in the intensive care unit patient. Blood. 2016;128(26):3032-3042. doi:10.1182/blood-2016-09-693655.
  2. Joly BS, Coppo P, Veyradier A. Thrombotic thrombocytopenic purpura. Blood. 2017;129(21):2836-2846. doi:10.1182/blood-2016-10-709857.
  3. Leslie SD, Toy PT. Laboratory hemostatic abnormalities in massively transfused patients given red blood cells and crystalloid. Am J Clin Pathol. 1991;96(6):770-773.
  4. Neunert C, Lim W, Crowther M, et al. The American Society of Hematology 2011 evidence-based practice guideline for immune thrombocytopenia. Blood. 2011;117(16):4190-4207. doi:10.1182/blood-2010-08-302984.
  5. Kappler S, Ronan-Bentle S, Graham A. Thrombotic microangiopathies (TTP, HUS, HELLP). Emerg Med Clin North Am. 2014;32(3):649-671. doi:10.1016/j.emc.2014.04.008.
  6. Greinacher A. Heparin-Induced Thrombocytopenia. Solomon CG, ed. N Engl J Med. 2015;373(3):252-261. doi:10.1056/NEJMcp1411910.
  7. Reardon JE Jr., Marques MB. Evaluation of Thrombocytopenia. Lab Med. 2006;37(4):248-250. doi:10.1309/R7P79KERAJHPRHLT.
  8. Stasi R. How to approach thrombocytopenia. Hematology Am Soc Hematol Educ Program. 2012;2012:191-197. doi:10.1182/asheducation-2012.1.191.
  9. Gauer RL, Braun MM. Thrombocytopenia. Am Fam Physician. 2012;85(6):612-622.
  10. Abrams CS. 172 – Thrombocytopenia. Twenty Fifth Edition. Elsevier Inc.; 2016:1159–1167.e2. doi:10.1016/B978-1-4557-5017-7.00172-0.
  11. Wilson CS, Vergara-Lluri ME, Brynes RK. Chapter 11 – Evaluation of Anemia, Leukopenia, and Thrombocytopenia. Second Edition. Elsevier Inc.; 2017:195-234.e195. doi:10.1016/B978-0-323-29613-7.00011-9.
  12. Hui P, Cook DJ, Lim W, Fraser GA, Arnold DM. The frequency and clinical significance of thrombocytopenia complicating critical illness: a systematic review. Chest. 2011;139(2):271-278. doi:10.1378/chest.10-2243.
  13. Jokiranta TS. HUS and atypical HUS. Blood. 2017;129(21):2847-2856. doi:10.1182/blood-2016-11-709865.
  14. Neunert CE. Management of newly diagnosed immune thrombocytopenia: can we change outcomes? Hematology Am Soc Hematol Educ Program. 2017;2017(1):400-405. doi:10.1182/asheducation-2017.1.400.
  15. Lambert MP, Gernsheimer TB. Clinical updates in adult immune thrombocytopenia. Blood. 2017;129(21):2829-2835. doi:10.1182/blood-2017-03-754119.
  16. Arepally GM. Heparin-induced thrombocytopenia. Blood. 2017;129(21):2864-2872. doi:10.1182/blood-2016-11-709873.
  17. Aster RH, Bougie DW. Drug-induced immune thrombocytopenia. N Engl J Med. 2007;357(6):580-587. doi:10.1056/NEJMra066469.
  18. Boral BM, Williams DJ, Boral LI. Disseminated Intravascular Coagulation. Am J Clin Pathol. 2016;146(6):670-680. doi:10.1093/ajcp/aqw195.
  19. Scully M, Hunt BJ, Benjamin S, et al. Guidelines on the diagnosis and management of thrombotic thrombocytopenic purpura and other thrombotic microangiopathies. Br J Haematol. 2012;158(3):323-335. doi:10.1111/j.1365-2141.2012.09167.x.
  20. Levine RL, Hursting MJ, Drexler A, Lewis BE, Francis JL. Heparin-induced thrombocytopenia in the emergency department. Ann Emerg Med. 2004;44(5):511-515. doi:10.1016/j.annemergmed.2004.06.004.

Hepatobiliary Ultrasound

Brief H&P:

A 43-year-old female with a history of hypertension, diabetes and obesity presents with right-upper quadrant abdominal pain for the past 1 week. The pain is characterized as burning, non-radiating, intermittent (with episodes lasting 10-30 minutes), resolving spontaneously and without apparent provoking features. She notes nausea but no vomiting, no changes in bowel or urinary habits. She similarly denies fevers, chest pain or shortness of breath. Vital signs were normal, and physical examination was notable only for right upper quadrant tenderness to palpation without rigidity or guarding.

An ECG demonstrates normal sinus rhythm, laboratory tests including liver function tests and lipase were normal and a bedside ultrasound of the right upper quadrant was performed demonstrating gallstones and a positive sonographic Murphy sign. The patient was diagnosed with acute cholecystitis, antibiotics were initiated, the patient was maintained NPO while general surgery was consulted.

Evaluation of Right-Upper Quadrant Abdominal Pain

The initial evaluation of a patient presenting with right-upper quadrant (or adjacent) abdominal pain typically includes laboratory tests such as a complete blood count, chemistry panel, liver function tests and serum lipase. In patients at risk for atypical presentations for an acute coronary syndrome or with other concerning symptoms, electrocardiography and cardiac enzymes may be indicated.

The differential diagnosis is broad. A systematic approach proceeds anatomically from superficial to deeper structures centered around the site of maximal pain.

Skin

Skin

Herpes zoster, erysipelas, or cellulitis

Connective Tissue

Connective Tissue

Intercostal muscle strain, myositis, fasciitis

Bone

Bone

Rib contusion or fracture

Hepatobiliary

Hepatobiliary

Hepatitis (infectious, toxin-mediated), perihepatitis (Fitz-Hugh-Curtis), hepatic abscess, symptomatic cholelithiasis, acute cholecystitis, ascending cholangitis, pancreatitis

Gastric

Gastric

Peptic ulcer disease, gastroesophageal reflux, gastritis, gastroparesis

Small Bowel

Small Bowel

Duodenal ulcer, small bowel obstruction

Large Bowel

Large Bowel

Retrocecal appendicitis, inflammatory bowel disease

Genitourinary

Genitourinary

Pyelonephritis, ureterolithiasis

Referred

Referred

Acute coronary syndrome, lower-lobe pneumonia, pulmonary embolus

Ultrasound in the Evaluation of Right Upper Quadrant Abdominal Pain

The diagnosis is unlikely to be made based on laboratory tests alone 1. However, the addition of bedside ultrasound, particularly for the evaluation of gallbladder pathology, is both rapid and reliable 2-8. The algorithm below provides a pathway for the incorporation of bedside ultrasound of the right upper quadrant in the evaluation of suspected gallbladder disease.

Algorithm for the Use of Ultrasound in the Evaluation of Right Upper Quadrant Abdominal Pain

A normal-appearing gallbladder absent gallstones should prompt a traversal of the anatomic approach to the differential diagnosis detailed above. If gallstones are identified, the association with a positive sonographic Murphy sign is highly predictive of acute cholecystitis 2,5,6,9. Acute cholecystitis may be associated with inflammatory gallbladder changes such as wall-thickening (>3mm) or pericholecystic fluid 3,5,6,10-13. However, in the absence of cholelithiasis or a positive sonographic Murphy sign, these features are non-specific and may be the result of generalized edematous states such as congestive heart failure, renal failure, or hepatic failure and critically-ill patients may develop acalculous cholecystitis 7,11,14. Finally, common bile duct dilation may be due to intra-luminal obstruction as in choledocholithiasis, luminal abnormalities such as strictures, or extra-luminal compression from masses or malignancy.  Dilation is generally described as a diameter >6mm – allowing an additional 1mm for every decade over 60 years-old as well as more vague accommodations for patients with prior cholecystectomy 3,5,7,15.

Gallery

The POCUS Atlas
The ultrasound images and videos used in this post come from The POCUS Atlas, a collaborative collection focusing on rare, exotic and perfectly captured ultrasound images.
The POCUS Atlas

Gallstones

Many gallstones

Gallbladder wall thickening

Pericholecystic fluid

Choledocholithiasis

Common bile duct dilation

All illustrations are available for free, licensed (along with all content on this site) under Creative Commons Attribution-ShareAlike 4.0 International Public License.

Downloads Page License

References

  1. Trowbridge RL, Rutkowski NK, Shojania KG. Does this patient have acute cholecystitis? JAMA. 2003;289(1):80-86.
  2. Scruggs W, Fox JC, Potts B, et al. Accuracy of ED Bedside Ultrasound for Identification of gallstones: retrospective analysis of 575 studies. West J Emerg Med. 2008;9(1):1-5.
  3. Ross M, Brown M, McLaughlin K, et al. Emergency physician-performed ultrasound to diagnose cholelithiasis: a systematic review. Acad Emerg Med. 2011;18(3):227-235. doi:10.1111/j.1553-2712.2011.01012.x.
  4. Jang T, Chauhan V, Cundiff C, Kaji AH. Assessment of emergency physician-performed ultrasound in evaluating nonspecific abdominal pain. Am J Emerg Med. 2014;32(5):457-460. doi:10.1016/j.ajem.2014.01.004.
  5. Kendall JL, Shimp RJ. Performance and interpretation of focused right upper quadrant ultrasound by emergency physicians. J Emerg Med. 2001;21(1):7-13.
  6. Summers SM, Scruggs W, Menchine MD, et al. A prospective evaluation of emergency department bedside ultrasonography for the detection of acute cholecystitis. Ann Emerg Med. 2010;56(2):114-122. doi:10.1016/j.annemergmed.2010.01.014.
  7. Rubens DJ. Ultrasound Imaging of the Biliary Tract. Ultrasound Clinics. 2007;2(3):391-413. doi:10.1016/j.cult.2007.08.007.
  8. Rosen CL, Brown DF, Chang Y, et al. Ultrasonography by emergency physicians in patients with suspected cholecystitis. American Journal of Emergency Medicine. 2001;19(1):32-36. doi:10.1053/ajem.2001.20028.
  9. Shea JA. Revised Estimates of Diagnostic Test Sensitivity and Specificity in Suspected Biliary Tract Disease. Arch Intern Med. 1994;154(22):2573-2581. doi:10.1001/archinte.1994.00420220069008.
  10. Miller AH, Pepe PE, Brockman CR, Delaney KA. ED ultrasound in hepatobiliary disease. J Emerg Med. 2006;30(1):69-74. doi:10.1016/j.jemermed.2005.03.017.
  11. Shah K, Wolfe RE. Hepatobiliary ultrasound. Emergency Medicine Clinics of NA. 2004;22(3):661–73–viii. doi:10.1016/j.emc.2004.04.015.
  12. Matcuk GR, Grant EG, Ralls PW. Ultrasound measurements of the bile ducts and gallbladder: normal ranges and effects of age, sex, cholecystectomy, and pathologic states. Ultrasound Q. 2014;30(1):41-48. doi:10.1097/RUQ.0b013e3182a80c98.
  13. Engel JM, Deitch EA, Sikkema W. Gallbladder wall thickness: sonographic accuracy and relation to disease. American Journal of Roentgenology. 1980;134(5):907-909. doi:10.2214/ajr.134.5.907.
  14. Gerstenmaier JF, Hoang KN, Gibson RN. Contrast-enhanced ultrasound in gallbladder disease: a pictorial review. Abdom Radiol (NY). 2016;41(8):1640-1652. doi:10.1007/s00261-016-0729-4.
  15. Becker BA, Chin E, Mervis E, Anderson CL, Oshita MH, Fox JC. Emergency biliary sonography: utility of common bile duct measurement in the diagnosis of cholecystitis and choledocholithiasis. J Emerg Med. 2014;46(1):54-60. doi:10.1016/j.jemermed.2013.03.024.

Neonatal Congenital Heart Disease

Brief H&P

An 8-day old male infant, ex-full term, born by normal spontaneous vaginal delivery and discharged home 2 days after birth without identified complications or maternal infections presents with parents to the emergency department due to decreased activity. Starting on day-of-life six, the family noted that feeding appeared to be taking longer and the mother felt her infant was breathing faster.

On presentation, the patient was pale, dusky, lethargic and with mottled skin. Temperature 36.3°C (rectal), HR 170, RR 60, BP 62/35, SpO2 70%. Physical examination demonstrated flat fontanelle, coarse breath sounds, regular rate and rhythm without additional heart sounds or murmurs, and hepatomegaly with liver edge 3cm below costal margin. Capillary refill was delayed at 5-6 seconds. Supplemental oxygen was applied without effect.

Algorithm for the Evaluation and Management of Suspected Congenital Heart Disease in Neonates

Algorithm for the Evaluation of Neonatal Congenital Heart Disease

Neonates with undiagnosed congenital heart disease may present to the emergency department with nonspecific symptoms, and may be considerably unstable requiring immediate life-saving interventions.

Key Historical Features

  • Respiratory difficulty
  • Feeding difficulty (small quantities, diaphoresis during feeding)
  • Poor weight gain
  • Chromosomal abnormalities, syndromes
  • Maternal risk factors: diabetes, teratogen exposure, substance use
  • Sibling of affected child

Key Examination Findings

  • Vital signs: tachycardia, tachypnea, hypotension
  • Blood pressure differential (RUE vs. LE >8mmHg difference)
  • Pulse oximetry differential (RUE vs. LE >4% difference, <95%)
  • Cardiac examination: murmur, thrill, pulse differential, capillary refill, hepatomegaly

Workup

  • CXR: Evaluate for cardiomegaly, pulmonary vascular congestion
  • ECG: Evaluate for axis deviation (right axis deviation is normal for neonate)
  • ABG with co-oximetry

References

  1. Special thanks to Dr. Kelly Young, MD, MS, FAAP. Director, Pediatric Emergency Medicine Fellowship. Harbor-UCLA Medical Center Department of Emergency Medicine.
  2. Association AAOPAAH. Textbook of Neonatal Resuscitation. 2016.
  3. Lissauer T, Fanaroff AA, Miall L, Fanaroff J. Neonatology at a Glance. John Wiley & Sons; 2015.
  4. Steinhorn RH. Evaluation and Management of the Cyanotic Neonate. Clinical Pediatric Emergency Medicine. 2008;9(3):169-175. doi:10.1016/j.cpem.2008.06.006.
  5. MD MR. Chapter 7 – Cardiology. Twenty First Edition. Elsevier Inc.; 2018:156-202. doi:10.1016/B978-0-323-39955-5.00007-7.
  6. Gomella T, Cunningham M. Neonatology 7/E. McGraw-Hill Prof Med/Tech; 2013.
  7. Yee L. Cardiac emergencies in the first year of life. Emergency Medicine Clinics of NA. 2007;25(4):981–1008–vi. doi:10.1016/j.emc.2007.08.001.
  8. Yates MC, Rao PS. Pediatric cardiac emergencies. Emerg Med. 2013. doi:10.4172/2165-7548.1000164.
  9. Silberbach M, Hannon D. Presentation of congenital heart disease in the neonate and young infant. Pediatr Rev. 2007;28(4):123-131.
  10. Mastropietro CW, Tourner SP, Sarnaik AP. Emergency presentation of congenital heart disease in children. Pediatric Emergency …. 2008.
  11. Brousseau T, Sharieff GQ. Newborn Emergencies: The First 30 Days of Life. Pediatric Clinics of North America. 2006;53(1):69-84. doi:10.1016/j.pcl.2005.09.011.

Hyperthermia

Brief H&P

A young male with unknown medical history is brought in by ambulance with altered mental status. EMS reports that the patient was agitated, requiring restraints for transportation. On arrival, the patient is agitated, uncooperative and unable to provide history. Vital signs are notable for tachycardia, tachypnea and hypertension. Physical examination demonstrates diaphoresis and mydriasis, as well as increased muscle tone – particularly in the lower extremities with ankle clonus. A core temperature is obtained and noted to be elevated at 41.5°C. Point-of-care glucose is normal.

Rapid external cooling measures were instituted and several doses of intravenous benzodiazepines were administered with improvement in agitation. Laboratory studies were notable for a modest leukocytosis (WBC 18.4 without immature forms), serum sodium was 135 without osmolar gap, creatine kinase was slightly elevated without renal dysfunction, and thyroid function tests were normal. Toxicology screen was negative. ECG revealed sinus tachycardia but was otherwise normal and non-contrast computed tomography of the head was normal.

After a brief admission in the intensive care unit, the patient’s mental status improved and he reported MDMA use on the evening of presentation, he also described a history of major depression and was taking paroxetine.

Evaluation of Elevated Temperature

The designation of 38°C as “suspicious” for fever dates to 1868 and the analysis of over one million (axillary) temperature measurements by Carl Wunderlich1. Any cutoff is arbitrary and requires recognition of the clinical context and normal daily variations (with nadir in the morning and peak in evening) 2,3. What is clear is that peripheral thermometry (unless demonstrating fever) is unreliable and a core temperature should be sought4.

Thermoregulation

Temperature homeostasis is a balance between heat production and dissipation maintained by the anterior hypothalamus. Heat production is a byproduct of normal metabolic processes and skeletal muscle activity. Conservation, maintenance or dissipation of heat is aided by cutaneous vasodilation, sweating, or behavioral responses.

Fever is caused by endogenous or exogenous pyrogens which alter the homeostatic set-point, inducing thermogenesis and elevating the body temperature. Precipitants of fever are usually infectious, however non-infectious processes (ex. malignancy, tissue ischemia/infarction, auto-immune disease) resulting in inflammation can provoke a similar response 5-7.

There is no explicit temperature distinction to diagnose hyperthermia, instead the physiologic mechanism is different. In hyperthermia, the body’s homeostatic mechanisms are dysfunctional or overwhelmed due to heat exposure, excess production, ineffective dissipation or hypothalamic malfunction 8.

Algorithm for the Evaluation of Hyperthermia 8-15

Algorithm for the Evaluation of Hyperthermia

Implicated Agents in Drug-Induced Hyperthermic Syndromes 9,10

Serotonin Syndrome

Class Examples
SSRI sertraline, fluoxetine, paroxetine
Other anti-depressants trazodone, venlafaxine, lithium
MAOI phenelzine, isocarboxazid
Anti-epileptic drugs valproate
Analgesics meperidine, fentanyl, tramadol
Anti-emetic ondansetron, metoclopramide
Anti-migraine sumatriptan
Antimicrobial linezolid, ritonavir
Illicit substances MDMA, LSD

Neuroleptic Malignant Syndrome (NMS)

Class Examples
Typical anti-psychotic haloperidol, prochlorperazine
Atypical anti-psychotic risperidone, olanzapine, quetiapine, aripiprazole
Anti-dopaminergic metoclopramide, droperidol

References:

  1. Wunderlich CA. Das Verhalten Der Eigenwärme in Krankheiten. 1870.
  2. Mackowiak PA, Wasserman SS, Levine MM. A critical appraisal of 98.6 degrees F, the upper limit of the normal body temperature, and other legacies of Carl Reinhold August Wunderlich. JAMA. 1992;268(12):1578-1580.
  3. Lee-Chiong TL, Stitt JT. Disorders of temperature regulation. Compr Ther. 1995;21(12):697-704.
  4. Niven DJ, Gaudet JE, Laupland KB, Mrklas KJ, Roberts DJ, Stelfox HT. Accuracy of peripheral thermometers for estimating temperature: a systematic review and meta-analysis. Ann Intern Med. 2015;163(10):768-777. doi:10.7326/M15-1150.
  5. Dinarello CA. Infection, fever, and exogenous and endogenous pyrogens: some concepts have changed. J Endotoxin Res. 2004;10(4):201-222. doi:10.1179/096805104225006129.
  6. Greisman LA, Mackowiak PA. Fever: beneficial and detrimental effects of antipyretics. Curr Opin Infect Dis. 2002;15(3):241-245.
  7. Dinarello CA. Thermoregulation and the pathogenesis of fever. Infect Dis Clin North Am. 1996;10(2):433-449.
  8. Simon HB. Hyperthermia. N Engl J Med. 1993;329(7):483-487. doi:10.1056/NEJM199308123290708.
  9. Boyer EW, Shannon M. The serotonin syndrome. N Engl J Med. 2005;352(11):1112-1120. doi:10.1056/NEJMra041867.
  10. Berman BD. Neuroleptic malignant syndrome: a review for neurohospitalists. Neurohospitalist. 2011;1(1):41-47. doi:10.1177/1941875210386491.
  11. Hayes BD, Martinez JP, Barrueto F. Drug-induced hyperthermic syndromes: part I. Hyperthermia in overdose. Emerg Med Clin North Am. 2013;31(4):1019-1033. doi:10.1016/j.emc.2013.07.004.
  12. Oruch R, Pryme IF, Engelsen BA, Lund A. Neuroleptic malignant syndrome: an easily overlooked neurologic emergency. Neuropsychiatr Dis Treat. 2017;13:161-175. doi:10.2147/NDT.S118438.
  13. Musselman ME, Saely S. Diagnosis and treatment of drug-induced hyperthermia. Am J Health Syst Pharm. 2013;70(1):34-42. doi:10.2146/ajhp110543.
  14. Ahuja N, Cole AJ. Hyperthermia syndromes in psychiatry. Adv psychiatr treat (Print). 2018;15(03):181-191. doi:10.1192/apt.bp.107.005090.
  15. Tomarken JL, Britt BA. Malignant hyperthermia. Ann Emerg Med. 1987;16(11):1253-1265. doi:10.1016/S0196-0644(87)80235-4.

Wide-complex Tachycardia

Several algorithms exist for the electrocardigraphic evaluation of regular, wide-complex tachycardias with the objective of distinguishing ventricular tachycardia (VT) from a supraventricular tachycardia (SVT) with aberrant conduction. The algorithm detailed below, developed by Dr. James Niemann, presents an ED-centric approach favoring the diagnosis of the more life-threatening dysrhythmia. This approach recognizes that SVT with aberrancy is rare, particularly in patients with a history of cardiac disease where the likelihood of ventricular tachycardia exceeds 90%. The algorithm requires the use of only the most simple and easily-recalled criteria, and any point of failure along the algorithm lends to the universally-appropriate management as ventricular tachycardia.

Algorithm for the Evaluation of Regular, Wide-Complex Tachycardia

Algorithm for the Evaluation of Wide-Complex Tachycardia

  1. aVR: Is the initial deflection in aVR positive? If yes, then VT.
  2. Concordance: Is there concordance (monophasic with same polarity) in all of the precordial leads? If yes, then VT.
  3. AV Dissociation: Is there evidence of AV dissociation (fusion or capture beats)? If yes, then VT.
  4. Bundle-branch morphology: Is the QRS morphology in V1 and V6 consistent with either LBBB or RBBB? If no, then VT.

References

  1. Neimann J. Wide QRS Complex Tachycardias. Lecture. Harbor-UCLA Department of Emergency Medicine. 2014:1-19.
  2. Vereckei A, Duray G, Szénási G, Altemose GT, Miller JM. New algorithm using only lead aVR for differential diagnosis of wide QRS complex tachycardia. Heart Rhythm. 2008;5(1):89-98. doi:10.1016/j.hrthm.2007.09.020.
  3. Szelényi Z, Duray G, Katona G, et al. Comparison of the “real-life” diagnostic value of two recently published electrocardiogram methods for the differential diagnosis of wide QRS complex tachycardias. Acad Emerg Med. 2013;20(11):1121-1130. doi:10.1111/acem.12247.
  4. Brugada P, Brugada J, Mont L, Smeets J, Andries EW. A new approach to the differential diagnosis of a regular tachycardia with a wide QRS complex. Circulation. 1991;83(5):1649-1659.
  5. Lau EW, Pathamanathan RK, Ng GA, Cooper J, Skehan JD, Griffith MJ. The Bayesian approach improves the electrocardiographic diagnosis of broad complex tachycardia. Pacing Clin Electrophysiol. 2000;23(10 Pt 1):1519-1526.
  6. B Garner J, M Miller J. Wide Complex Tachycardia – Ventricular Tachycardia or Not Ventricular Tachycardia, That Remains the Question. Arrhythm Electrophysiol Rev. 2013;2(1):23-29. doi:10.15420/aer.2013.2.1.23.
  7. Vereckei A. Current algorithms for the diagnosis of wide QRS complex tachycardias. Curr Cardiol Rev. 2014;10(3):262-276.
  8. Garmel GM. Wide Complex Tachycardias: Understanding this Complex Condition: Part 1 – Epidemiology and Electrophysiology. West J Emerg Med. 2008;9(1):28-39.
  9. Garmel GM. Wide Complex Tachycardias: Understanding this Complex Condition Part 2 – Management, Miscellaneous Causes, and Pitfalls. West J Emerg Med. 2008;9(2):97-103.
  10. Griffith MJ, Garratt CJ, Mounsey P, Camm AJ. Ventricular tachycardia as default diagnosis in broad complex tachycardia. The Lancet. 1994;343(8894):386-388.

Ultrasound in Ectopic Pregnancy

Brief HPI:

A 27 year-old female is brought in by ambulance with syncope. Pre-hospital providers report that the patient developed pelvic pain, vaginal bleeding and lost consciousness. On their arrival, her blood pressure was 80mmHg systolic, point-of-care glucose was normal – a peripheral IV was started, fluids were administered and the patient was transported to the emergency department. On arrival, vital signs were notable for tachycardia and hypotension. The patient was lethargic, maintaining arousal only with constant verbal or noxious stimulation. Her abdomen was markedly tender throughout with rebound and involuntary guarding. Her last menstrual period was 5 weeks ago and she suspected that she was pregnant. Peripheral venous access was expanded and uncrossmatched blood products were rapidly transfused. Whole blood on a point-of-care pregnancy test was positive1, and a bedside FAST demonstrated free intraperitoneal fluid in the hepatorenal recess with large free pelvic fluid. Gynecology was consulted for emergent operative management of suspected ruptured ectopic pregnancy with hemorrhagic shock and the patient was taken to the operating room.

Algorithm for the Evaluation of Suspected Ectopic Pregnancy

Algorithm for the evaluation of ectopic pregnancy

Gallery

The POCUS Atlas
The ultrasound images and videos used in this post come from The POCUS Atlas, a collaborative collection focusing on rare, exotic and perfectly captured ultrasound images.
The POCUS Atlas

Ruptured Cornual Ectopic

Tubal Ectopic Pregnancy

Tubal Ectopic Pregnancy

Ectopic Pregnancy

Ectopic Pregnancy

Positive FAST in Ruptured Ectopic

Positive FAST in Ruptured Ectopic

The evaluation of suspected ectopic pregnancy, as with all complaints in the emergency department, begins with an assessment of patient stability: airway, breathing and circulation. The unstable patient requires immediate interventions to secure each critical component, all temporizing measures until the patient can be taken to the operating room for definitive management.

The evaluation and management algorithm for stable patients is dependent on findings of transabdominal & transvaginal ultrasonography, quantitative hCG level (relative to the institution-dependent discriminatory zone), and the identification of high risk historical and examination features that would prompt specialist consultation despite otherwise benign diagnostic tests.

If ultrasonography demonstrates a definite ectopic pregnancy (extrauterine live embryo,  adnexal mass containing yolk sac), gynecology consultation is warranted – the table below details candidates for attempts at pharmacologic therapy.

Requirements for methotrexate administration2,3

Absolute
Hemodynamic stability
Ultrasound findings consistent with an ectopic pregnancy
Willingness of the patient to adhere to close follow-up
No existing organ dysfunction: hepatic, renal, pulmonary, hematologic, immune
Relative
Unruptured ectopic mass <3.5cm
No fetal cardiac activity detected
hCG <5000 mIU/L

If an intrauterine pregnancy is identified such as a live embryo or yolk sac, barring the presence of risk factors for heterotopic pregnancy (namely, the use of assisted fertilization methods 2, 4-6), then an alternative cause for the patient’s symptoms should be sought.

If the ultrasound is non-diagnostic, patients should be stratified according to risk based on historical features, examination findings and quantitative hCG. If the hCG is above the institutional discriminatory zone, the absence of a definitive IUP is concerning, elevating suspicion for a non-visualized ectopic and warrants gynecology consultation. If the hCG is below the discriminatory zone, then certain features such as the presence of abdominal, adnexal or cervical motion tenderness, or high-risk ultrasonographic features including greater-than-moderate free pelvic fluid, complex fluid, or complex adnexal masses may be secondary features of ectopic pregnancy – again warranting consultation. If no high-risk features are present, close follow-up with repeat hCG and ultrasonography is reasonable.

Risk factors for ectopic pregnancy3

Risk factor OR
Previous tubal surgery 21
Sterilization 9.3
Previous ectopic 8.3
In utero exposure to diethylstilbestrol 5.6
Current IUD 5.0
History of PID 3.4
Infertility 2.7
Advanced maternal age 1.4-2.9
Smoking 1.5-3.9

Examination Findings in Ectopic Pregnancy6

Finding LR+
Cervical motion tenderness 4.9
Peritoneal irritation 4.2
Adnexal mass 2.4
Adnexal tenderness 1.9

Ultrasound Findings in Ectopic Pregnancy 7

Finding LR+
Ectopic cardiac activity >100
Ectopic gestational sac 23
Ectopic mass and fluid in Pouch of Douglas 9.9
Fluid in Pouch of Douglas 4.4
Ectopic mass 3.6
No IUP 2.2
Normal adnexa 0.55

Algorithm for the Evaluation of Vaginal Bleeding

Algorithm for the evaluation of vaginal bleeding

References:

  1. Fromm C, Likourezos A, Haines L, Khan ANGA, Williams J, Berezow J. Substituting whole blood for urine in a bedside pregnancy test. J Emerg Med. 2012;43(3):478-482. doi:10.1016/j.jemermed.2011.05.028.
  2. Bhatt S, Ghazale H, Dogra VS. Sonographic Evaluation of Ectopic Pregnancy. Radiol Clin North Am. 2007;45(3):549-560. doi:10.1016/j.rcl.2007.04.009.
  3. Barash JH, Buchanan EM, Hillson C. Diagnosis and management of ectopic pregnancy. Am Fam Physician. 2014;90(1):34-40.
  4. Lin EP, Bhatt S, Dogra VS. Diagnostic Clues to Ectopic Pregnancy. Radiographics. 2008;28(6):1661-1671. doi:10.1148/rg.286085506.
  5. Winder S, Reid S, Condous G. Ultrasound diagnosis of ectopic pregnancy. Australas J Ultrasound Med. 2011;14(2):29-33. doi:10.1002/j.2205-0140.2011.tb00192.x.
  6. Crochet JR, Bastian LA, Chireau MV. Does this woman have an ectopic pregnancy?: the rational clinical examination systematic review. JAMA. 2013;309(16):1722-1729. doi:10.1001/jama.2013.3914.
  7. Mol BW, van Der Veen F, Bossuyt PM. Implementation of probabilistic decision rules improves the predictive values of algorithms in the diagnostic management of ectopic pregnancy. Hum Reprod. 1999;14(11):2855-2862.
  8. First-Trimester Emergencies: A Practical Approach To Abdominal Pain And Vaginal Bleeding In Early Pregnancy. October 2003:1-20.
  9. Paspulati RM, Bhatt S, Nour S. Sonographic evaluation of first-trimester bleeding. Radiol Clin North Am. 2004;42(2):297-314. doi:10.1016/j.rcl.2004.01.005.
  10. Anderson FWJ, Hogan JG, Ansbacher R. Sudden Death: Ectopic Pregnancy Mortality. Obstet Gynecol. 2004;103(6):1218-1223. doi:10.1097/01.AOG.0000127595.54974.0c.
  11. Lozeau A-M, Potter B. Diagnosis and management of ectopic pregnancy. Am Fam Physician. 2005;72(9):1707-1714.
  12. Stone MB. Emergency Ultrasound Diagnosis of Ruptured Ectopic Pregnancy. Academic Emergency Medicine. 2009;16(12):1378-1378. doi:10.1111/j.1553-2712.2009.00538.x.
  13. Stein JC, Wang R, Adler N, et al. Emergency Physician Ultrasonography for Evaluating Patients at Risk for Ectopic Pregnancy: A Meta-Analysis. Ann Emerg Med. 2010;56(6):674-683. doi:10.1016/j.annemergmed.2010.06.563.
  14. Fromm C, Likourezos A, Haines L, Khan ANGA, Williams J, Berezow J. Substituting whole blood for urine in a bedside pregnancy test. J Emerg Med. 2012;43(3):478-482. doi:10.1016/j.jemermed.2011.05.028.
  15. Alkatout I, Honemeyer U, Strauss A, et al. Clinical diagnosis and treatment of ectopic pregnancy. Obstet Gynecol Surv. 2013;68(8):571-581. doi:10.1097/OGX.0b013e31829cdbeb.
  16. Arleo EK, DeFilippis EM. Cornual, interstitial, and angular pregnancies: clarifying the terms and a review of the literature. Clinical Imaging. 2014;38(6):763-770. doi:10.1016/j.clinimag.2014.04.002.
  17. Rodgers SK, Chang C, DeBardeleben JT, Horrow MM. Normal and Abnormal US Findings in Early First-Trimester Pregnancy: Review of the Society of Radiologists in Ultrasound 2012 Consensus Panel Recommendations. Radiographics. 2015;35(7):2135-2148. doi:10.1148/rg.2015150092.
  18. Diagnosis and Management of Ectopic Pregnancy: Green-top Guideline No. 21. BJOG. 2016;123(13):e15-e55. doi:10.1111/1471-0528.14189.
  19. Hahn SA, Promes SB, Brown MD, et al. Clinical Policy: Critical Issues in the Initial Evaluation and Management of Patients Presenting to the Emergency Department in Early Pregnancy. Ann Emerg Med. 2017;69(2):241–250.e20. doi:10.1016/j.annemergmed.2016.11.002.
  20. Lee R, Dupuis C, Chen B, Smith A, Kim YH. Diagnosing ectopic pregnancy in the emergency setting. Ultrasonography. 2018;37(1):78-87. doi:10.14366/usg.17044.

A history of the ddxof: mobile application

I’ve wanted a mobile companion application for ddxof for a while. I’m not entirely sure that anyone else feels strongly about it, but I use the content regularly on shift and trying to load even the mobile-optimized website on my phone was cumbersome. Dropbox worked for a while but it didn’t maintain the taxonomy I’d assigned on the website and text content wasn’t included.

While I have some experience with web development, a quick peek at Objective C and native app development suggested I would be in over my head. So, I sought some funding, designed a few basic screens in Sketch, and waited to see what the development team came up with.

Sketches of different screens on the app

Version 1.0

The app hung on this screen for 20 seconds on launch

When it loaded, things looked pretty good

It even had working favorites

In November, I saw the final product and it was a bit of a fixer-upper. Much of the functionality was present (including adding Favorites). Unfortunately, less attention seemed to have been paid to certain usability aspects and the visual style I’d developed in the design compositions.

Most glaring was the lack of any representation of a loading state. It pained me to watch coworkers download the app and see a blank screen that ignored their interaction attempts for a solid 20 seconds on the app’s initial launch.

Luckily, I got access to the source code and found that it was built with something called React Native. As I sifted through the code, I realized that I recognized and (mostly) understood what was happening. It was basically JavaScript, I know JavaScript! The display and styling portions were also easy to grasp as they’re similar to HTML and CSS respectively.

I tried to work backwards from the code I’d received but it was just too hard to grasp. The extent of my JavaScript experience prior to this was rudimentary so after going back and forth a few times between attempting to improve upon the existing app and just starting from scratch, I decided to dive in and begin anew.

Version 2.0

A real loading indicator

I lost a few things, no multiple algorithms, no categories/tags

By version 2.3, we had post categories/tags and a gallery view for multiple algorithms

Exactly 1 month later, I released version 2.0 of the ddxof: mobile application. Since it was built from scratch, I had to remove some of the features that were too complex for me to develop. Removing the option to save favorites was a tough choice but I was excited to have a version of the application that at least wouldn’t make me cringe when I saw it in use.

The only reason I was even able to get that far was the truly impressive community surrounding React Native. I thought of them a bit like plugins, and using a few components really simplified the process of interacting with the website’s API and storing content for offline use.

In landscape mode, the header occupied pretty much the entire screen

Version 2.4.2 shrunk the header down

Over the next two months, I worked on iterative functional and visual improvements including better server- and client-side caching, and the ability to see all of post’s algorithms (with an image gallery “plugin”). Things settled down by version 2.4.2, it worked, was mostly bug free, and I took a break.

Version 3.0

As I used the app more, a few things kept bugging me. I really missed being able to save favorites and I was often annoyed that the app didn’t allow interaction during attempts at refreshing content (even though usable cached content was available).

Version 3.0 with a more subdued color scheme

Favorites are back

Cached content remains accessible if a network error occurs

I knew favorites was going to be a problem, I’d tried tackling it earlier when I started working on version 2.0 but had given up. The problem is that an article marked as a favorite needs to be recognized across all parts of the application. This notion of state management in React Native seemed to commonly be handled by a library called Redux. However, despite my best efforts I simply could not wrap my head around the logic. After all, I’m still not a developer and I found myself getting lost in descriptions of “actions” and “reducers”. I was thrilled when I found Mobx which accomplished everything I needed in a much more understandable fashion. My favorites list became an observable that I could access and remained alive wherever I needed it and making the information persist on the user’s device was laughably easy with another plugin.

Using Mobx also meant that I could check for content updates in the background without interrupting the user’s ability to interact with cached content. The small indicator area lets users refresh the content, notify them of a refresh attempt and even connection errors.

The uncollapsed header in landscape mode

The header animates down when scrolling

I also took the opportunity to touch up a few interface issues. The header shrinks with a hopefully-subtle animation when scrolling to provide more space for content. I was also finding the red a bit overwhelming, the muted grays are much more my style.

I’m happy to announce that version 3.0 is now available on the App Store and Google Play Store. Please try it out and let me know what you think!

Sinus Tachycardia

Brief History and Physical:

A young female with a history of schizophrenia presents to the emergency department reporting hallucinations. She had been diagnosed with schizophrenia one year previously and was briefly admitted to a psychiatric hospital. She discontinued her anti-psychotic (risperidone) two months ago, and over the past week she reports increasingly prominent auditory and visual hallucinations.

She denies recent illness, vomiting/diarrhea, changes in urinary habits, new medications, alcohol or illicit substance use. She also denies chest pain, palpitations or shortness of breath.

Vital signs are notable for a heart rate of 148bpm and are otherwise normal (including core temperature). Detailed physical examination is normal except for a rapid, regular heart rate. Mental status examination demonstrated normal level of alertness and orientation, linear and cogent responses and occasional response to internal stimuli during which she appeared anxious.

Initial evaluation and management included a 12-lead ECG which showed sinus tachycardia. Multiple boluses of normal saline were initiated while awaiting laboratory workup.

ECG: Sinus Tachycardia

Presentation ECG demonstrates sinus tachycardia.

Update:

Laboratory studies were reviewed and unremarkable. Normal hemoglobin, normal chemistry panel, negative hCG, and negative toxicology screen. The patient remained persistently tachycardic with a heart rate ranging from 140-160bpm (again sinus tachycardia on 12-lead ECG). An atypical antipsychotic and anxiolytic were administered and additional studies were obtained. Serum TSH, troponin and D-dimer were normal and bedside ultrasound did not identify a pericardial effusion. The patient remained asymptomatic, reporting subjective improvement in anxiety and hallucinations. Psychiatry was consulted and the patient was placed in observation for monitoring of sinus tachycardia. Observation course was uneventful as the patient remained asymptomatic. Transthoracic echocardiography was normal. Psychiatry consultation recommended resumption of home anti-psychotic and outpatient follow-up. Tachycardia had improved but not resolved at the time of discharge (heart rate 109bpm) and the patient was instructed to follow-up with her primary care provider.


Algorithm for the Evaluation of Sinus Tachycardia

Algorithm for the Evaluation of Sinus Tachycardia

Any vital sign derangement is concerning and tachycardia may be associated with unanticipated death after discharge home1. The presence of tachycardia suggests one of several categories of hemodynamic, autonomic, or endocrine/metabolic derangement.

Demand for increased cardiac output

A perceived demand for increased cardiac output will prompt chronotropic (and inotropic) amplification before hypotension develops. Causative etiologies include: volume depletion (from hemorrhage, gastrointestinal or renal losses), distributive processes (such as infection), obstruction (pulmonary embolus, or pericardial effusion with impending tamponade), or tissue hypoxia (anemia or lung disease).

Autonomic nervous system

Autonomic nervous system disturbances induced by stimulant, sympathomimetic or anti-cholinergic use, or withdrawal of certain agents such as ethanol or beta-blockers may be at fault.

Endocrine and other causes

Hyperthyroidism and pheochromocytoma should be considered, and as diagnoses of exclusion: anxiety, pain, or inappropriate sinus tachycardia2.

Evaluation:
Core temperature
CBC
Troponin
D-dimer
Bedside cardiac ultrasound
Urine toxicology screen
Ethanol level
TSH/T4

Algorithm for the Evaluation of Narrow-Complex Tachycardia3,4,5,6

Algorithm for the Evaluation of Narrow-Complex Tachycardia

References:

  1. Sklar DP, Crandall CS, Loeliger E, Edmunds K, Paul I, Helitzer DL. Unanticipated Death After Discharge Home From the Emergency Department. Ann Emerg Med. 2007;49(6):735-745. doi:10.1016/j.annemergmed.2006.11.018.
  2. Olshansky B, Sullivan RM. Inappropriate sinus tachycardia. J Am Coll Cardiol. 2013;61(8):793-801. doi:10.1016/j.jacc.2012.07.074.
  3. Yusuf S, Camm AJ. Deciphering the sinus tachycardias. Clin Cardiol. 2005;28(6):267-276.
  4. Katritsis DG, Josephson ME. Differential diagnosis of regular, narrow-QRS tachycardias. Heart Rhythm. 2015;12(7):1667-1676. doi:10.1016/j.hrthm.2015.03.046.
  5. Bibas L, Levi M, Essebag V. Diagnosis and management of supraventricular tachycardias. CMAJ. 2016;188(17-18):E466-E473. doi:10.1503/cmaj.160079.
  6. Link MS. Clinical practice. Evaluation and initial treatment of supraventricular tachycardia. N Engl J Med. 2012;367(15):1438-1448. doi:10.1056/NEJMcp1111259.

Tetanus Prophylaxis

An Algorithm for Tetanus Prophylaxis in Adults1

Algorithm for Tetanus Prophylaxis in Adults

References:

  1. Diphtheria, tetanus, and pertussis: recommendations for vaccine use and other preventive measures. Recommendations of the Immunization Practices Advisory committee (ACIP). MMWR Recomm Rep. 1991;40(RR-10):1-28.

ECG Guide: Pediatrics

ECG Standard

  • Full standard: no adjustment
  • Half-standard: commensurate reduction in amplitude (usually 50%)
  • Mixed: reduction in amplitude of precordial leads

Atrial Abnormalities

Right Atrial Abnormality (P pulmonale)
Peaked P-wave in II (>3mm from 0-6mo or >2.5mm >6mo)
Causes: right atrial volume overload, ASD, Ebstein, Fontan
Left Atrial Abnormality (P mitrale)
Wide, notched P-wave in II or biphasic in V1
Causes: MS, MR

Axis

  • Anatomical dominance of right ventricle until approximately 6mo
  • RAD normal
  • eRAD suggests AV canal defect

T-waves

  • 1st week of life: Upright
  • Adolescent: Inverted
  • Adult: Upright

Ventricular Hypertrophy

Right Ventricular Hypertrophy
R-wave height >98% for age in lead V1
S-wave depth >98% for age in lead V6
T-wave abnormality (ex. upright in childhood)
Causes: pHTN, PS, ToF
Left Ventricular Hypertrophy
R-wave height >98% for age in lead V6
S-wave depth >98% for age in lead V1
Adult-pattern R-wave progression in newborn (no large R-waves and small S-waves in right precordial leads)
Left-axis deviation
Causes: AS, coarctation, VSD, PDA

Examples


Normal Neonatal ECG

  • 2mo old
  • RAD
  • Inverted T-waves (normal)
  • Tall R-waves in V1-V3


Extreme Axis Deviation

  • Neonate with Down syndrome
  • Isoelectric in I, Negative in aVF negative in II  mean QRS vector -87°
  • Extreme RAD suggestive of AV canal defect


LVH:

  • Unrepaired Coarctation
  • Deep S-wave in V1 (>98%)
  • Tall R-wave in V6 (>98%)


RVH:

  • 10 year-old boy with pulmonary Hypertension
  • RAD after expected age for normal RAD
  • Tall R-waves in V1 (>98%)
  • Deep S-wave in V6 (>98%)


STEMI

  • ALCAPA (anomalous origin of the left coronary artery from the pulmonary artery): coronary artery arises anomalously from the pulmonary artery; as pulmonary arterial pressure falls during the first 6 months of infancy, prograde flow through the left coronary artery ceases and may even reverse.
  • HLHS (hypoplastic left heart syndrome): coronary arteries are perfused from a hypoplastic, narrow aorta that is susceptible to flow disruption
  • Orthotopic heart transplant with allograft vasculopathy
  • Kawasaki: coronary artery aneurysm with subsequent thrombosis


Benign early repolarization

  • 14 year-old male
  • Concave ST-segment elevation


Left Atrial Abnormality:

  • 9mo female with mitral insufficiency
  • Broad biphasic P-wave in V1
  • Tall, notched P-wave in II


Prolonged QT interval

  • 18-year-old female
  • Familial long QT syndrome and a history of cardiac arrest


WPW:

  • Delta wave, shortened PR interval

References

  1. O’Connor M, McDaniel N, Brady WJ. The pediatric electrocardiogram. Part I: Age-related interpretation. Am J Emerg Med. 2008;26(2):221-228. doi:10.1016/j.ajem.2007.08.003.
  2. Goodacre S, McLeod K. ABC of clinical electrocardiography: Paediatric electrocardiography. BMJ. 2002;324(7350):1382-1385.
  3. O’Connor M, McDaniel N, Brady WJ. The pediatric electrocardiogram Part II: Dysrhythmias. Am J Emerg Med. 2008;26(3):348-358. doi:10.1016/j.ajem.2007.07.034.
  4. O’Connor M, McDaniel N, Brady WJ. The pediatric electrocardiogram Part III: Congenital heart disease and other cardiac syndromes. Am J Emerg Med. 2008;26(4):497-503. doi:10.1016/j.ajem.2007.08.004.
  5. Schwartz P. Guidelines for the interpretation of the neonatal electrocardiogram. Eur Heart J. 2002;23(17):1329-1344. doi:10.1053/euhj.2002.3274.

Ultrasound in Dyspnea

Brief H&P:

A 68 year-old male with a history of hypertension, diabetes, hyperlipidemia, chronic obstructive pulmonary disease and congestive heart failure (CHF) with depressed ejection fraction presents via ambulance with a chief complaint of shortness of breath. EMS reports that the patient was tachypneic and saturating 80% on ambient air on their arrival. En route, he received nebulized albuterol, nitroglycerin and was started on non-invasive positive pressure ventilation (NI-PPV).

On arrival, he remains uncomfortable-appearing with a respiratory rate of 35 breaths/min and accessory muscle use. His heart rate is 136bpm, blood pressure is 118/85mmHg, and he is saturating 95% on an FiO2 of 100%. Attempts to obtain a history are limited due to difficulty comprehending his responses with the PPV mask on, and prompt desaturation with it off. Lung auscultation is similarly challenging due to ambient and transmitted sounds, although basilar crackles and diffuse expiratory wheezing are appreciated. Cardiovascular examination reveals a rapid and irregularly irregular rhythm. Assessment of jugular venous distension is limited due to the patient’s body habitus and the presence of mask straps around the patient’s neck. Lower extremities demonstrate 2+ pitting edema, symmetric bilaterally. Intravenous access is established and laboratory tests are sent. The ECG technician and portable chest x-ray are called.

The case presentation above demonstrates a common emergency department scenario: a critically-ill patient with undifferentiated dyspnea. Specifically, the scenario reveals a situation where the physical examination is either obfuscated by technical challenges or otherwise indeterminate. The patient is at risk for deterioration and targeted intervention is mandatory. If a COPD exacerbation is assumed, additional nebulized breathing treatments are indicated – a potentially costly jolt of beta agonists if the patient’s atrial fibrillation and rapid ventricular response are the consequence of decompensated systolic heart failure. Take the route of decompensated CHF and prompt afterload reduction with diuresis would be next – if incorrect, not only would the primary cause go untreated, but his tenuously-maintained blood pressure may suffer.

Algorithm for the Use of Ultrasound in the Evaluation of Dyspnea

Algorithm for the Use of Ultrasound in the Evaluation of Dyspnea

1. Lung Ultrasound

An approach incorporating point-of-care ultrasonography may be useful. First, a thoracic ultrasound is performed where certain causative etiologies might be identified immediately – for example absent lung sliding suggesting pneumothorax, or signs of generalized or subpleural consolidation.

The POCUS Atlas
The ultrasound images and videos used in this post come from The POCUS Atlas, a collaborative collection focusing on rare, exotic and perfectly captured ultrasound images.
The POCUS Atlas

Pneumothorax

Hepatization

Shred Sign

Pleural Effusion

2. Cardiac Ultrasound

Other findings on lung ultrasound may point to causes that are not primarily pulmonary. For example, if diffuse B-lines are encountered a focused cardiac ultrasound can be performed to grossly evaluate ejection fraction and estimate right atrial pressure.

B-Lines

Depressed EF

Dilated IVC

3. Venous Ultrasound

Finally, if the lung ultrasound is largely unremarkable (A-lines), a sequence of ultrasonographic findings including right ventricular dilation and the presence of a deep venous thrombosis would point to pulmonary embolism as the diagnosis.

DVT

RV Dilation

All illustrations are available for free, licensed (along with all content on this site) under Creative Commons Attribution-ShareAlike 4.0 International Public License.

Downloads Page License

References

  1. Lichtenstein DA, Mezière GA, Lagoueyte J-F, Biderman P, Goldstein I, Gepner A. A-lines and B-lines: lung ultrasound as a bedside tool for predicting pulmonary artery occlusion pressure in the critically ill. Chest. 2009;136(4):1014-1020. doi:10.1378/chest.09-0001.
  2. Copetti R, Soldati G, Copetti P. Chest sonography: a useful tool to differentiate acute cardiogenic pulmonary edema from acute respiratory distress syndrome. Cardiovasc Ultrasound. 2008;6(1):16. doi:10.1186/1476-7120-6-16.
  3. Gallard E, Redonnet J-P, Bourcier J-E, et al. Diagnostic performance of cardiopulmonary ultrasound performed by the emergency physician in the management of acute dyspnea. Am J Emerg Med. 2015;33(3):352-358. doi:10.1016/j.ajem.2014.12.003.
  4. Lichtenstein DA. Lung ultrasound in the critically ill. Ann Intensive Care. 2014;4(1):1. doi:10.1186/2110-5820-4-1.
  5. Zanobetti M, Scorpiniti M, Gigli C, et al. Point-of-Care Ultrasonography for Evaluation of Acute Dyspnea in the ED. Chest. 2017;151(6):1295-1301. doi:10.1016/j.chest.2017.02.003.
  6. Lichtenstein DA, Mezière GA. Relevance of lung ultrasound in the diagnosis of acute respiratory failure: the BLUE protocol. Chest. 2008;134(1):117-125. doi:10.1378/chest.07-2800.
  7. Images from The POCUS Atlas
  8. Special thanks to Dr. Timothy Jang, Director Emergency Ultrasound Program, Director Emergency Ultrasound Fellowship, Associate Professor of Clinical Emergency Medicine, Department of Emergency Medicine at Harbor-UCLA

Technique for Video Laryngoscopy

Overview

Laryngoscopy had until recently remained relatively unchanged since the introduction of the Macintosh and Miller blades in the 1940’s. Advancements in fiberoptic technology have led to the development of multiple novel devices obviating line-of-sight requirements for direct laryngoscopy which may aid with endotracheal intubation in some populations. While there is no evidence to suggest that video laryngoscopy improves patient-centered outcomes, familiarity with the technique of video laryngoscopy is a critical educational objective for trainees who should be comfortable in the use of this and other rescue airway management adjuncts.

The image above shows a comparison of the curvature of straight (Miller), curved (Macintosh) and hyperangulated blades relative to the oral, pharyngeal and laryngeal axes. The hyperangulated blade easily positions a fiberoptic camera over the glottic opening, allowing easy visualization of the vocal cords. Passing the endotracheal tube without direct line-of-sight becomes the challenge of intubation.

The purpose of this guide is to explore the differences in technique for performing video laryngoscopy compared to direct laryngoscopy. Specifically, the guide is focused on video laryngoscopes with hyper-angulated blades (Verathon Glidescope, Storz C-MAC D-Blade) as these devices pose more challenges for appropriate use while potentially offering the greatest advantages for glottic visualization in challenging airway management.


Advantages and Disadvantages

Advantages1

  • Improved glottic visualization especially in scenarios with limited neck mobility as there is no need to align the oral-pharyngeal-laryngeal axes.
  • Allows others to view the screen and facilitate endotracheal intubation.

Disadvantages1

  • Difficulty passing endotracheal tube despite improved glottic visualization.
  • Obscured view by fogging or contaminated airway (blood, secretions, vomit).
  • Possibility for deterioration of skills in direct laryngoscopy.

Technique

Blade Insertion

Because of it’s unique shape, special care should be taken when inserting a hyperangulated blade to avoid dental/oropharyngeal injury. The handle of the blade may need to be angled towards the patient’s chest and turned slightly to facilitate atraumatic insertion.

Blade Advancement

Transition to viewing the screen once the tip of the blade is past the visualized posterior portion of the tongue. Advance the blade along the base of the tongue while monitoring the view on screen. Identify the epiglottis and guide the tip of the blade into the vallecula, the objective is to center the glottic aperture in the upper 2/3 of the screen.

Optimal View

The optimal view shows the vocal cords centered in the upper 2/3 of the screen. This provides adequate screen “real estate” to show the endotracheal tube entering the screen and provide more visual feedback as the tube position is manipulated.

Blade Adjustment

The shape of the hyperangulated blade means that visualizing the airway is less dependent on the lifting motion applied with direct laryngoscopy. Instead, angulating the tip of the blade upward by gently rocking the handle back (taking great care to avoid dental/oropharyngeal trauma) will dramatically improve the view.

Endotracheal Tube Insertion

Directly visualize the insertion of the endotracheal tube into the oral cavity. The endotracheal tube should be loaded with an appropriately angulated rigid stylet. Follow the curvature of the laryngoscope blade entering from the right corner of the mouth. When the endotracheal tube is passed along the edge of the laryngoscope blade, few adjustments will be required for successful endotracheal intubation.

Endotracheal Tube Position Adjustments

If the view is optimized but the endotracheal tube is off-center and does not directly pass the vocal cords into the trachea, subtle adjustments to the endotracheal tube can help guide it into position. Hold the endotracheal tube like a pencil, turning it slightly clockwise or counter-clockwise between your index finger and thumb to manipulate the distal tip left or right above the laryngeal opening.

Stylet Removal

Once past the vocal cords, the hyperangulated rigid stylet will limit continued passage of the endotracheal tube into the trachea as it will get stuck on the anterior surface of the trachea. To facilitate easy passage into the trachea, the stylet should be pulled back slightly to allow passage into the trachea before being fully removed and the tube secured in position.


Review of Evidence

Emergency Department:

  • C-MAC associated with higher rate of successful intubation and greater proportion of grade I-II Cormack-Lehane views compared to direct laryngoscopy.5
  • Glidescope associated with higher rate of successful intubation (and fewer esophageal complications) compared to direct laryngoscopy. 6
  • Glidescope associated with higher rate of successful intubation compared to direct laryngoscopy. 7

Adjustments to Challenging Tube Placement:

  • Combination of flexible-tipped endotracheal tube with rigid stylet (Verathon GlideRight stylet) may increase intubation success.8
  • No apparent benefit to “reverse camber” loading of stylet into endotracheal tube. Reverse camber loading references placing the angled stylet 180° opposite to the natural curvature of the endotracheal tube.9
  • If a malleable stylet is used, 90° angulation was associated with higher rates of successful intubation. 10

Recent Data:

  • Propensity score-matched analysis of multicenter emergency department airway registry – no significant difference in rates of successful intubation comparing Glidescope to direct laryngoscopy. 11
  • Randomized trial comparing direct and video laryngoscopy using C-MAC showed no difference in rates of successful intubation, duration of intubation attempt, aspiration events or length of hospitalization. For interventions randomized to direct laryngoscopy, the video laryngoscope screen was covered. 12

Meta-Analyses:

  • Meta-analysis (predominantly for intubations in the operating room) suggests video laryngoscopy associated with fewer failed intubations, particularly among patients with anticipated difficult airway. Insufficient evidence to analyze effects on incidence of hypoxia, respiratory complications, time to intubation, or mortality.13

References

  1. Maldini B, Hodžović I, Goranović T, Mesarić J. CHALLENGES IN THE USE OF VIDEO LARYNGOSCOPES. Acta Clin Croat. 2016;55 Suppl 1:41-50. doi:10.20471/acc.2016.55.s1.05.
  2. Levitan RM, Heitz JW, Sweeney M, Cooper RM. The complexities of tracheal intubation with direct laryngoscopy and alternative intubation devices. Ann Emerg Med. 2011;57(3):240-247. doi:10.1016/j.annemergmed.2010.05.035.
  3. Hurford WE. The video revolution: a new view of laryngoscopy. Respir Care. 2010;55(8):1036-1045.
  4. Cheyne DR, Doyle P. Advances in laryngoscopy: rigid indirect laryngoscopy. F1000 Med Rep. 2010;2:61. doi:10.3410/M2-61.
  5. Sakles JC, Mosier J, Chiu S, Cosentino M, Kalin L. A Comparison of the C-MAC Video Laryngoscope to the Macintosh Direct Laryngoscope for Intubation in the Emergency Department. Ann Emerg Med. 2012;60(6):739-748. doi:10.1016/j.annemergmed.2012.03.031.
  6. Sakles JC, Mosier JM, Chiu S, Keim SM. Tracheal Intubation in the Emergency Department: A Comparison of GlideScope® Video Laryngoscopy to Direct Laryngoscopy in 822 Intubations. J Emerg Med. 2012;42(4):400-405. doi:10.1016/j.jemermed.2011.05.019.
  7. MD JMM, MPH USP, BA SC, MD JCS. Difficult Airway Management in the Emergency Department: GlideScope Videolaryngoscopy Compared to Direct Laryngoscopy. J Emerg Med. 2012;42(6):629-634. doi:10.1016/j.jemermed.2011.06.007.
  8. Radesic BP, Winkelman C, Einsporn R, Kless J. Ease of intubation with the Parker Flex-Tip or a standard Mallinckrodt endotracheal tube using a video laryngoscope (GlideScope). AANA J. 2012;80(5):363-372.
  9. Jones PM, Turkstra TP, Armstrong KP, et al. Effect of stylet angulation and endotracheal tube camber on time to intubation with the GlideScope. Can J Anesth/J Can Anesth. 2007;54(1):21-27.
  10. Turkstra TP, Harle CC, Armstrong KP, et al. The GlideScope-specific rigid stylet and standard malleable stylet are equally effective for GlideScope use. Can J Anesth/J Can Anesth. 2007;54(11):891-896.
  11. Choi HJ, Kim Y-M, Oh YM, et al. GlideScope video laryngoscopy versus direct laryngoscopy in the emergency department: a propensity score-matched analysis. BMJ Open. 2015;5(5):e007884-e007884. doi:10.1136/bmjopen-2015-007884.
  12. Driver BE, Prekker ME, Moore JC, Schick AL, Reardon RF, Miner JR. Direct Versus Video Laryngoscopy Using the C-MAC for Tracheal Intubation in the Emergency Department, a Randomized Controlled Trial. Acad Emerg Med. 2016;23(4):433-439. doi:10.1111/acem.12933.
  13. Lewis SR, Butler AR, Parker J, Cook TM, Smith AF. Videolaryngoscopy versus direct laryngoscopy for adult patients requiring tracheal intubation. Cochrane Database Syst Rev. 2016;11:CD011136. doi:10.1002/14651858.CD011136.pub2.

ECG Guide: Part II

STEMI

STEMI

  • ST-segment elevation ≥ 1mm in two contiguous leads
  • : ≥ 2mm V2-V3
  • : ≥ 1.5mm V2-V3

Posterior STEMI

  • ST-segment depression V1-V3 Posterior ECG
  • ST-segment elevation ≥ 0.5mm in V7-V9

Sgarbossa Criteria

  • Evaluation for STEMI in LBBB or paced rhythm
  • Normal: ST-segment discordant with QRS

    • QRS associated with ST-segment depression
    • QRS associated with (commensurate) ST-segment elevation
  • Score ≥ 3 98% specific for MI

Elevation

  • Concordant ST-segment elevation ≥ 1mm in any lead (5 points)

Depression

  • Concordant ST-segment depression ≥ 1mm in V1-V3 (3 points)

Discordant Elevation

  • Discordant ST-segment elevation ≥ 5mm in any lead (2 points)

Modified Sgarbossa Criteria

  • ST:S ratio ≥ 0.25 in any lead
  • Presence of any criterion is positive

Other Causes of ST-segment Elevation

Benign Early Repolarization

  • Concave ST-segment elevation
  • Notch at J-point
  • Asymmetric T-waves (steeper descent)

Pericarditis

  • Diffuse ST-segment elevation (except aVR)
  • PR-segment depression
  • Ratio: ST-elevation to T-wave amplitude ≥ 0.25 in V6 suggests pericarditis

LVH Strain

  • ST-segment elevation in V1-V3 in the setting of LVH

LV Aneurysm

  • Q-waves with ST-segment elevation in precordial leads

Ischemia and Prior Infarcts

Wellens: Type A

Wellens: Type B

Q-waves

  • ≥ 40ms duration
  • Depth ≥ 25% of R-wave height

Syncope

ARVD

  • Epsilon wave

Brugada Syndrome: Type 1

  • Type 1: Coved ST-segment elevation

Brugada Syndrome: Type 2

  • Type 2: Saddle-back ST-segment elevation

HCM

  • Deep, narrow Q-waves

Wolff-Parkinson-White

  • Shortened PR-interval
  • Delta-wave

Other

Atrial Abnormalities

  1. Normal
  2. RAA: P-wave amplitude > 2.5mm in inferior leads
  3. LAA: P-wave duration increased (terminal negative portion >0.04s), amplitude of terminal negative component >1mm below isoelectric line in V1

Left Bundle Branch Block


  • QRS duration > 0.12s (3 boxes)
  • Broad or notched R-wave with prolonged upstroke in I, aVL, V5, V6
  • Associated ST-segment depression and T-wave inversion
  • Reciprocal changes in V1, V2 (deep S-wave)
  • Possible LAD

Right Bundle Branch Block


  • QRS duration > 0.12s (3 boxes)
  • RSR’ in V1, V2
  • Reciprocal changes in I, aVL, V5, V6 (deep S-wave)

Axes

All illustrations are available for free, licensed (along with all content on this site) under Creative Commons Attribution-ShareAlike 4.0 International Public License.

Downloads Page License

CT Interpretation: Head

The emergency physician should be adept at the interpretation of computed tomography of the head, particularly for life-threatening processes where awaiting a radiologist interpretation may unnecessarily delay care.

As with the approach detailed previously for imaging of the abdomen and pelvis, a similar structured method for interpretation of head imaging exists and follows the mnemonic “Blood Can Be Very Bad”.

Normal Neuroanatomy

Brainstem
Posterior Fossa
High Pons
Cisterns
Ventricles

Blood: Blood

Density
Acute: hyperdense (50-100HU)
1-2wks: isodense with brain
2-3wks: hypodense with brain

Types/Locations

Intraparenchymal Hemorrhage/Contusions
Sudden deceleration of the head causes the brain to impact on bony prominences (e.g., temporal, frontal, occipital poles).
Non-traumatic hemorrhagic lesions seen more frequently in elderly and located in basal ganglia.
Intraventricular Hemorrhage
White density in otherwise black ventricular spaces, can lead to obstructive hydrocephalus and elevated ICP.
Associated with worse prognosis in trauma.
Subarachnoid Hemorrhage
Hemorrhage into subarachnoid space usually filled with CSF (cistern, brain convexity).
Extracranial Hemorrhage
Presence of significant extracranial blood or soft-tissue swelling should point examiner to evaluation of underlying brain parenchyma, opposing brain parenchyma (for contrecoup injuries) and underlying bone for identification of fractures.

Can: Cisterns


Evaluating the cisterns is important for the identification of increased intracranial pressures (assessed by effacement of spaces) and presence of subarachnoid blood.

  • Circummesencephalic: CSF ring around midbrain and most sensitive marker for elevated ICP
  • Suprasellar: Star-shaped space above the sella
  • Quadrigeminal: W-shaped space at the top of the midbrain
  • Sylvian: Bilateral space between temporal/frontal lobes

Be: Brain

Evaluate the brain parenchyma, including an assessment of symmetry of the gyri/sulci pattern, midline shift, and a clear gray-white differentiation.

Very: Ventricles

Evaluate the ventricles for dilation or compression. Compare the ventricle size to the size of cisterns, large ventricles with normal/compressed cisterns and sulcal spaces suggests obstruction.

Bad: Bone

Switch to bone windows to evaluate for fracture. The identification of small, linear, non-depressed skull fractures may be difficult to identify as they are often confused with sutures – surrogates include pneumocephalus, and abnormal aeration of mastoid air cells and sinuses. The Presence of fractures increases the suspicion for intracranial injury, search adjacent and opposing parenchyma and extra-axial spaces.

Example #1

ct-mass_01
ct-mass_01
ct-mass_02
ct-mass_02
ct-mass_03
ct-mass_03
ct-mass_04
ct-mass_04
ct-mass_05
ct-mass_05
ct-mass_06
ct-mass_06
ct-mass_07
ct-mass_07
ct-mass_08
ct-mass_08
ct-mass_09
ct-mass_09
ct-mass_10
ct-mass_10
ct-mass_11
ct-mass_11
ct-mass_12
ct-mass_12
ct-mass_13
ct-mass_13
ct-mass_14
ct-mass_14
ct-mass_15
ct-mass_15
ct-mass_16
ct-mass_16
ct-mass_17
ct-mass_17
ct-mass_18
ct-mass_18
ct-mass_19
ct-mass_19
ct-mass_20
ct-mass_20
ct-mass_21
ct-mass_21
ct-mass_22
ct-mass_22
ct-mass_23
ct-mass_23
ct-mass_24
ct-mass_24

CT Head Interpretation

  • Ill-defined lesion in right parietal white matter with a large amount of surrounding vasogenic edema with midline shift and right uncal herniation.
  • Acute on subacute right extra-axial subdural hematoma.
  • Effacement of basilar cisterns.

Example #2

ct-sdh_01
ct-sdh_01
ct-sdh_02
ct-sdh_02
ct-sdh_03
ct-sdh_03
ct-sdh_04
ct-sdh_04
ct-sdh_05
ct-sdh_05
ct-sdh_06
ct-sdh_06
ct-sdh_07
ct-sdh_07
ct-sdh_08
ct-sdh_08
ct-sdh_09
ct-sdh_09
ct-sdh_10
ct-sdh_10
ct-sdh_11
ct-sdh_11
ct-sdh_12
ct-sdh_12
ct-sdh_13
ct-sdh_13
ct-sdh_14
ct-sdh_14
ct-sdh_15
ct-sdh_15
ct-sdh_16
ct-sdh_16
ct-sdh_17
ct-sdh_17
ct-sdh_18
ct-sdh_18
ct-sdh_19
ct-sdh_19
ct-sdh_20
ct-sdh_20
ct-sdh_21
ct-sdh_21

CT Head Interpretation

  • Bilateral subacute subdural hematomas, left larger than right and associated with rightward midline shift.
  • Left lateral ventricle is partially effaced.

Example #3

ct-trauma_01
ct-trauma_01
ct-trauma_02
ct-trauma_02
ct-trauma_03
ct-trauma_03
ct-trauma_04
ct-trauma_04
ct-trauma_05
ct-trauma_05
ct-trauma_06
ct-trauma_06
ct-trauma_07
ct-trauma_07
ct-trauma_08
ct-trauma_08
ct-trauma_09
ct-trauma_09
ct-trauma_10
ct-trauma_10
ct-trauma_11
ct-trauma_11
ct-trauma_12
ct-trauma_12
ct-trauma_13
ct-trauma_13
ct-trauma_14
ct-trauma_14
ct-trauma_15
ct-trauma_15
ct-trauma_16
ct-trauma_16
ct-trauma_17
ct-trauma_17
ct-trauma_18
ct-trauma_18
ct-trauma_19
ct-trauma_19
ct-trauma_20
ct-trauma_20
ct-trauma_21
ct-trauma_21
ct-trauma_22
ct-trauma_22
ct-trauma_23
ct-trauma_23
ct-trauma_24
ct-trauma_24
ct-trauma_25
ct-trauma_25

CT Head Interpretation

Subdural hematoma with significant herniation

References

  1. Perron A. How to read a head CT scan. Emergency Medicine. 2008.
  2. Arhami Dolatabadi A, Baratloo A, Rouhipour A, et al. Interpretation of Computed Tomography of the Head: Emergency Physicians versus Radiologists. Trauma Mon. 2013;18(2):86–89. doi:10.5812/traumamon.12023.

Sickle Cell Crises

Brief H&P

A 27 year-old male with sickle cell disease (HbSC) on hydroxurea and with a history of 2-3 hospitalizations per year for vaso-occlusive pain crises manifested by arthralgias and back pain presents to the emergency department with 3 days of worsening joint pain affecting his entire body but predominantly his knees and lower back. He is familiar with this pain and attempted therapy at home with ibuprofen, then hydrocodone-acetaminophen, and finally hydromorphone without improvement and presented to the emergency department.

On review of systems, he denied chest pain, cough, or shortness of breath. He has some periumbilical abdominal pain but tolerated normal oral intake on the day of presentation without vomiting nor changes in bowel habits. He otherwise denied fevers, peripheral numbness/weakness, urinary or fecal incontinence or retention. He similarly denies trauma, weight loss, night sweats, or intravenous drug use.

Objectively, the patient’s vital signs were normal and he was well-appearing. Mucous membranes were moist and skin turgor was normal. There were no appreciable joint effusions, warmth, nor limitation to active/passive range of motion of any joints. His back had no midline tenderness to palpation or percussion, normal range of motion in all axes and extremity sensation and strength testing were normal. Abdominal and genitourinary examinations were normal. The patient had preserved perineal sensation to light touch and normal rectal tone – a core temperature was obtained which was also normal.

Peripheral access was established and a parenteral dose of hydromorphone equivalent to his home oral dose was administered (0.015mg/kg). Repeat dosing was required at 15 minutes due to persistent pain scale of 10. Diphenhydramine and acetaminophen were also administered, for potential opioid-sparing effects, recognizing the limited evidence to support these relatively benign adjuncts.

Laboratory studies were notable for anemia (though stable compared to baseline measures), appropriate reticulocyte count, no evidence of hemolysis and with normal electrolytes and renal function.

A thorough history and examination did not identify a critical precipitant for the patient’s symptoms which were presumed to be secondary to a vaso-occlusive pain crisis. On reassessment, the patient’s pain was improved and an oral dose of hydromorphone was administered with continued observation and serial reassessments for two hours thereafter. The patient’s hematologist was available for follow-up the subsequent morning and the patient was discharged home.

Pharmacokinetics of Commonly-Used Opiate Analgesics1-3

Medication Route Onset Peak Duration
Morphine IV 5-10min 20min 3-5h
IM 15-30min 30-60min
PO 30min 1h
Oxycodone PO 10-15min 30-60min 3-6h
Hydrocodone PO 10-20min 4-8h
Fentanyl IV <1min 2-5min 30-60min
Hydromorphone IV 5min 10-20min 3-4h
PO 15-30min 30-60min
Codeine PO 30-60min 60-90min 4-6h

Spectrum of Sickle Cell Trait and Disease4

Algorithm for the Evaluation and Management of Sickle Cell Crises4-10

Algorithm for the Management of Sickle Cell Crises

References:

  1. Lexicomp Online®, Adult Drug Information, Hudson, Ohio: Lexi-Comp, Inc.; November 4, 2017.
  2. Trescot AM, Datta S, Lee M, Hansen H. Opioid pharmacology. Pain Physician. 2008;11(2 Suppl):S133-S153.
  3. Vieweg WVR, Lipps WFC, Fernandez A. Opioids and methadone equivalents for clinicians. Prim Care Companion J Clin Psychiatry. 2005;7(3):86-88.
  4. Glassberg J. Evidence-based management of sickle cell disease in the emergency department. Emergency Medicine Practice. 2011;13(8):1–20–quiz20.
  5. Raam R, Mallemat H, Jhun P, Herbert M. Sickle Cell Crisis and You: A How-to Guide. Ann Emerg Med. 2016;67(6):787-790. doi:10.1016/j.annemergmed.2016.04.016.
  6. Piel FB, Steinberg MH, Rees DC. Sickle Cell Disease. N Engl J Med. 2017;376(16):1561-1573. doi:10.1056/NEJMra1510865.
  7. Lovett PB, Sule HP, Lopez BL. Sickle cell disease in the emergency department. Emerg Med Clin North Am. 2014;32(3):629-647. doi:10.1016/j.emc.2014.04.011.
  8. Yawn BP, John-Sowah J. Management of Sickle Cell Disease: Recommendations From the 2014 Expert Panel Report. Vol 92. 2015:1069-1076.
  9. Zempsky WT. Evaluation and Treatment of Sickle Cell Pain in the Emergency Department: Paths to a Better Future. Clinical Pediatric Emergency Medicine. 2010;11(4):265-273. doi:10.1016/j.cpem.2010.09.002.
  10. Aliyu ZY, Tumblin AR, Kato GJ. Current therapy of sickle cell disease. Haematologica. 2006;91(1):7-10.

CT Interpretation: Abdomen/Pelvis

As with the systematic approach preferred for the evaluation and management of other processes explored on this site, a similarly structured method for the interpretation of imaging commonly obtained in the emergency department may afford the same benefits – namely, the timely identification of pathology while avoiding costly missed diagnoses. In this post, I propose an approach to the interpretation of computed tomography of the abdomen and pelvis.

Aorta Down

Thoracic Aorta

Thoracic Aorta

Start with the descending thoracic aorta

Abdominal Aorta

Abdominal Aorta

Follow the abdominal aorta down including its branches (celiac, SMA, paired renal arteries, IMA)

Aortic Bifurcation

Aortic Bifurcation

Continue to the bifurcation of the abdominal aorta to the left and right common iliac arteries

Veins Up

Femoral Veins

Femoral Veins

Start with the left and right femoral veins

Inferior Vena Cava

Inferior Vena Cava

Follow the inferior vena cava up

Infrahepatic IVC

Infrahepatic IVC

The inferior vena cava gains contrast from the renal veins

Right Atrium

Right Atrium

The inferior vena cava empties into the right atrium

Solid Organs Down

Heart and Pericardium

Heart and Pericardium

Evaluate for the presence of a pericardial effusion or cardiomegaly

Spleen

Spleen

Heterogenous contrast-enhancement is normal

Pancreas

Pancreas

The tail of the pancreas lies in the hilum of the spleen

Liver

Liver

Evaluate the intrahepatic bile ducts for dilation or pneumobilia, portal venous system for gas, and liver parenchyma for vascular abnormalities or abscesses

Gallbladder

Gallbladder

Evaluate for radioopaque stones, pericholecystic fluid or surrounding fat stranding

Adrenal

Adrenal

A wishbone-shaped structure superior to the kidneys

Kidney and Ureter

Kidney and Ureter

Evaluate for hydronephrosis or hydroureter

Bladder

Bladder

Continue down into the pelvis; in a female patient the evaluation should include the uterus and adnexa

Rectum Up

Rectum

Rectum

Having reached the inferior-most portion of the image following solid organs, move upward again from the rectum

Sigmoid

Sigmoid

Evaluate the sigmoid colon for diverticulitis

Transverse

Transverse

Continue following the sigmoid colon up the descending colon to the transverse colon and the hepatic flexure

Cecum

Cecum

Continue down the ascending colon to the cecum

Appendix

Appendix

At the cecum, attempt to identify a small tubular structure (the appendix) - evaluate for periappendiceal fat stranding, perforation or abscess

Esophagus Down

Esophagus

Esophagus

Start at the esophagus, evaluate for perforation or hernia

Stomach

Stomach

Continue to the stomach and duodenum

Small Bowel

Small Bowel

Evaluate the small bowel for obstruction (dilation, air-fluid levels)

Tissue-specific Windows

Lung Window

Lung Window

Switch to lung window to evaluate the lung parenchyma and continue through the abdomen to identify intraperitoneal free air

Bone Window

Bone Window

Use the bone window to identify fractures or lytic lesions

Try It Yourself

ct_annotation_01
ct_annotation_01
ct_annotation_02
ct_annotation_02
ct_annotation_03
ct_annotation_03
ct_annotation_04
ct_annotation_04
ct_annotation_05
ct_annotation_05
ct_annotation_06
ct_annotation_06
ct_annotation_07
ct_annotation_07
ct_annotation_08
ct_annotation_08
ct_annotation_09
ct_annotation_09
ct_annotation_10
ct_annotation_10
ct_annotation_11
ct_annotation_11
ct_annotation_12
ct_annotation_12
ct_annotation_13
ct_annotation_13
ct_annotation_14
ct_annotation_14
ct_annotation_15
ct_annotation_15
ct_annotation_16
ct_annotation_16
ct_annotation_17
ct_annotation_17
ct_annotation_18
ct_annotation_18
ct_annotation_19
ct_annotation_19
ct_annotation_20
ct_annotation_20
ct_annotation_21
ct_annotation_21

CT Abdomen/Pelvis Interpretation

  • Cystic lesion in the inferior right lobe of the liver most consistent with hepatic abscess.
  • Multiple calcified gallstones in the gallbladder.

Pneumobilia: Hepatic Gas Applied

Brief HPI

A 45 year-old female with a history of pre-diabetes and gastroesophageal reflux disease presents with 3 days of epigastric abdominal pain. She describes constant, burning abdominal pain which worsened on the day of presentation associated with two episodes of non-bloody and non-bilious emesis. The patient was tender to palpation in the epigastrium and right upper quadrant.

Right upper quadrant ultrasound

Laboratory studies were largely normal. A complete blood count demonstrated minimal leukocytosis (11.6 with normal differential), and liver function tests were normal.

A right-upper quadrant ultrasound was obtained which demonstrated “strongly shadowing structures in the gallbladder fossa which might represent a wall-echo-shadow, calcified gallbladder wall, or air within the gallbladder”.

The patient underwent contrast-enhanced computed tomography of the abdomen and pelvis which is shown below.

Imaging

cyst-gastric_01
cyst-gastric_01
cyst-gastric_02
cyst-gastric_02
cyst-gastric_03
cyst-gastric_03
cyst-gastric_04
cyst-gastric_04
cyst-gastric_05
cyst-gastric_05
cyst-gastric_06
cyst-gastric_06
cyst-gastric_07
cyst-gastric_07
cyst-gastric_08
cyst-gastric_08
cyst-gastric_09
cyst-gastric_09
cyst-gastric_10
cyst-gastric_10
cyst-gastric_11
cyst-gastric_11
cyst-gastric_12
cyst-gastric_12
cyst-gastric_13
cyst-gastric_13
cyst-gastric_14
cyst-gastric_14
cyst-gastric_15
cyst-gastric_15

CT Abdomen/Pelvis with Contrast

Pneumobilia, intra- and extra-hepatic biliary duct dilation, pericholecystic fat stranding, and an air-fluid level within a contracted gallbladder. Mildly dilated loops of ileal bowel with a possible transition point in the right lower quadrant. Findings suggestive of possible gallstone ileus.

The patient was taken to the operating room for exploratory laparotomy, possible cholecystectomy and possible small bowel resection for presumed gallstone ileus. Intra-operative findings were notable for a cholecystogastric fistula which was repaired.

Differentiation between Portal Venous Gas and Pneumobilia

The patient’s CT demonstrated mostly central hepatic gas. This finding combined with the presence of an air-fluid level in the gallbladder was most consistent with pneumobilia. This case demonstrates an application of the previously-developed algorithm for the evaluation of hepatic gas in a relatively unique pathologic process.
Hepatic Gas: Pneumobilia  vs. Portal Venous Gas