Medical Student Clinical Pearl – Urinary Tract Infections

Urinary Tract Infections


Rob Hanlon, Med 1

Dalhousie Medicine New Brunswick, Class of 2021

Reviewed by: Dr David Lewis

 


 

Urinary tract infections (UTIs) are common in both the inpatient and outpatient settings. As such, it is important to understand the etiology, pathogenesis, and treatment of such infections. This post will focus primarily on uncomplicated UTIs, bacteriology and pathogenesis, treatment options with consideration for drug resistance.

Types of UTIs: 

The term UTI encompasses different infections. These include asymptomatic bacteriuria, acute uncomplicated cystitis, recurrent cystitis, complicated UTI, catheter-associated asymptomatic bacteriuria, catheter-associated UTI, prostatitis, and pyelonephritis. 1 There are two broad classifications: uncomplicated and complicated.

Uncomplicated UTIs refer to infections occurring in individuals with normal urinary tracts; meaning they have no structural or neurological issues, such as neurogenic bladder. These are differentiated into lower (bladder and urethra) and upper (ureters and kidneys) urinary tract infections; cystitis and pyelonephritis respectively. 2 Typical symptoms of cystitis include dysuria, urinary frequency and urgency, suprapubic pain, and hematuria. Symptoms of pyelonephritis include fever, chills, flank pain, costovertebral angle tenderness, and nausea/vomiting. 3

Risk factors of uncomplicated UTIs include being female (proximity of urethral opening to anus), frequent sexual intercourse, history of recurrent UTIs, use of spermicide-coated condoms, diaphragms, obesity, and diabetes. 3 Menopause also increases the risk for UTIs as the decrease in estrogen causes the walls of the urinary tract to thin, which decreases resistances to bacteria. 4 Uncomplicated UTIs do occur in men; albeit, less frequently than women. Risk factors in men include anal intercourse (fecal bacteria), lack of circumcision, and benign prostatic hyperplasia. 5

 

Complicated UTIs refer to infections that are typically more severe and difficult to treat. This type of infection can be seen in people with structural abnormalities impairing the flow of urine, catheter use or other foreign bodies, renal transplantation, and kidney/bladder dysfunction.4

 

Bacteriology and Pathogenicity:

There are two mechanism by which bacteria enter the urinary tract, these are ascending infections and haematogenous infections. The ascending mechanism occurs when perineal/fecal bacteria enter the urethra and travel up towards the bladder/kidneys. The haematogenous route occurs when bacteria from the blood enter the kidneys.6

 

Bacteria causing UTIs are termed uropathogens. The common UTI causing organisms are gram negative Klebsiella spp., Escherichia coli, and Proteus spp., and gram positive Enterococci spp. and Staphylococcus saprophyticus. E. coli being the most common uropathogen; seen in 80% of cases. More opportunistic organisms can be isolated in complicated UTIs, such as Pseudomonas spp. and fungal Candida spp.4 7

 

Uropathogenic E. coli (UPEC) strains contain virulence factors that allow them to colonize the urinary tract. Fimbriae are filamentous cell surface extensions that allow the bacteria to adhere to the uroepithelium and promote invasion into the tissue. Other surface molecules include flagella that allow the bacteria to mobilize up the urinary tract. 8 UPEC also produce toxins such as haemolysin, which damage epithelial cells and induce inflammatory responses (causing UTI symptoms). Factors allowing adherence of UPEC to uroepitehlium are paramount, as urine could wash away the bacteria. Other virulence factors allow the bacteria to thrive and grow. 6

 

Klebsiella spp. and Proteus spp. are other gram negative uropathogens that also produce fimbriae. Klebsiella produce polysaccharide capsules that prevent host defense phagocytosis.6  It also produces an enzyme called urease, produced by Proteus spp. as well, which hydrolyzes urea into ammonia and CO2. The bacteria use ammonia as a source of nitrogen for metabolism. The enzymatic process also increases the pH of the urinary tract and leads to the formation of renal stones. 9

Proteus

 

Pseudomonas aeruginosa is a gram-negative commonly associated with nosocomial acquired UTIs, especially when catheters are in place. Its major virulence factor is the production of biofilms, which protect it from host defenses and many antimicrobials. 6 Staphylococcus saprophyticus is a gram-positive bacterium that also produces biofilms, as well as a specific epithelial adhesion protein called lipoteichoic acid. 10

 

Although some of these uropathogens have similar virulence mechanisms, it is important to understand the different types of pathogens and their virulence factors because different antimicrobials target specific parts of the bacteria and the bacteria can be resistant to specific treatment options.

 

Treatment with Consideration for Antimicrobial Resistance

Multiple factors must be considered when choosing treatment options for UTIs in order to determine the risk of increased drug resistance. Patients are considered to be at a higher risk of drug resistance if, within the last three months, they have been found to have a multidrug resistant strain in their urine, they have been admitted to a hospital or other care facility, used broad-spectrum antibiotics, or have a travel history to areas known for resistant strains. 3

 

For low risk patients, treatments for uncomplicated cystitis include nitrofurantoin, trimethoprim-sulfamethoxazole, and fosfomycin. Choosing which drug depends on the individual’s allergies, local rates of resistance, and availability. If the patient has used one of these drugs within the last three months, the remaining two drugs are possible options. 3 If first-line treatments are not an option, then an oral beta-lactam, such as amoxicillin-clavulanate is appropriate. If allergic to this, then a fluoroquinolone such as ciprofloxacin can be used.3

 

Table 1: Drugs and dosages for empiric treatment of uncomplicated cystitis. 3

 

 

For higher risk patients, a urine culture and antimicrobial susceptibility testing should be ordered. First-line treatments (see above) can be used as empiric treatments until test results are obtained. However, if the patient is unable to take these treatments, test results should be obtained prior initiating treatment. 3

 

For complicated UTIs, such as catheter infections, treatment depends on the severity of the illness. Urine culture and susceptibility testing should be performed. In the case of a catheter infection, it should be removed and a sample from the catheter should be cultured. 11 If the catheterized patient requires treatment prior to obtaining test results, treatment should cover gram-negative bacilli. Third-generation cephalosporins can be used in this case. Critically ill patients should be put on broad spectrum antibiotics such as carbapenems and vancomycin, in order to cover pseudomonas and methicillin-resistant Staphylococcus aureus infections respectively. 12

Local (New Brunswick, Canada) Information on Antimicrobial Treatment of UTIs can be found here:

NB Antibiotic Guidelines and Resources

 

 

This is not an exhaustive description of infection types, treatments, or resistance mechanisms. This post focused on uncomplicated UTIs and their treatments because they are commonly seen in the clinical setting. An in-depth patient history is crucial for understanding the possible causes of a UTI and for developing a differential diagnosis. These should be included alongside test results when evaluating treatment options.

 

 


References:

 

  1. Kalpana Gupta, Larissa Grigoryan, Barbara Trautner. Urinary tract infection. Annals of Internal Medicine. 2017;167(7). https://search.proquest.com/docview/1975585404.

 

  1. Ana L Flores-Mireles, Jennifer N Walker, Michael Caparon, Scott J Hultgren. Urinary tract infections: Epidemiology, mechanisms of infection and treatment options. Nature Reviews. Microbiology. 2015;13(5):269. http://www.ncbi.nlm.nih.gov/pubmed/25853778. doi: 10.1038/nrmicro3432.

 

  1. Hooton T, Gupta K. Acute uncomplicated cystitis in women. Retrieved from: https://www.uptodate.com/contents/acute-uncomplicated-cystitis-in-women?source=see_link. Updated 2017.

 

  1. Harvey S. Urinary tract infection. University of Maryland. Retrieved from: http://www.umm.edu/health/medical/reports/articles/urinary-tract-infection. Updated 2012.

 

  1. Hooton T. Acute uncomplicated cystitis in men. Retrieved from: https://www.uptodate.com/contents/acute-uncomplicated-cystitis-in-men?source=see_link. Updated 2017.

 

  1. Walsh C, Collyns T. The pathophysiology of urinary tract infections. Surgery (Oxford). https://www.sciencedirect.com/science/article/pii/S0263931917300716. doi: 10.1016/j.mpsur.2017.03.007.

 

  1. Beyene G, Tsegaye W. Bacterial uropathogens in urinary tract infection and antibiotic susceptibility pattern in jimma university specialized hospital, southwest ethiopia. Ethiopian journal of health sciences. 2011;21(2):141. http://www.ncbi.nlm.nih.gov/pubmed/22434993. doi: 10.4314/ejhs.v21i2.69055.

 

  1. Bien J, Sokolova O, Bozko P. Role of uropathogenic escherichia coli virulence factors in development of urinary tract infection and kidney damage. International journal of nephrology. 2012;2012:681473. http://www.ncbi.nlm.nih.gov/pubmed/22506110. doi: 10.1155/2012/681473.

 

  1. Schaffer JN, Pearson MM. Proteus mirabilis and urinary tract infections. Microbiology spectrum. 2015;3(5). http://www.ncbi.nlm.nih.gov/pubmed/26542036.

 

  1. Raul Raz, Raul Colodner, Calvin M. Kunin. Who are you: Staphylococcus saprophyticus? Clinical Infectious Diseases. 2005;40(6):896-898. http://www.jstor.org/stable/4463165. doi: 10.1086/428353.
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RCP – Suprapubic Aspiration PoCUS

Suprapubic aspiration – when the catheter doesn’t cut it.

Resident Clinical Pearl (RCP) – Guest Resident Edition

Sean Davis MD, PGY2 Family Medicine

Dalhousie University, Yarmouth, Nova Scotia

Reviewed and Edited by Dr. David Lewis

 

Urine is routinely analyzed and cultured as part of a sick child workup, as diagnosis of urinary tract infection can be difficult in pre-verbal children. They are unable to “point where it hurts”, and physical exam can be both difficult and unreliable in an irritable or obtunded infant. Urine may be collected in three ways – by “clean catch” collection, transurethral catheterization (TUC), and suprapubic aspiration (SPA). Given the inherent risk of contamination with local flora (over 25% in one cohort study)1, clean catch urine is typically useful only for ruling out UTI. TUC is more commonly performed as it does not require physician participation, but SPA remains a valid option for obtaining a urine sample for analysis and culture in children under the age of 2. It has been shown to have a significantly lower rate of contamination than TUC (1% versus 12%, respectively)1, although failure rates are higher with SPA4. Use of portable ultrasound has been shown to significantly increase the rate of success of SPA (79% US guided vs 52% blind)5.

 

RCP – The pee or not the pee: so many questions!

 

Indications:2,3

  • Labial adhesions/edema
  • Phimosis
  • Diarrhea
  • Unsuccessful urethral catheterization
  • Urethral/introital surgery
  • Urethral stricture
  • Urethral trauma
  • Urinary retention
  • Urinalysis/culture in children younger than 2 years
  • Chronic urethral/periurethral gland infection

Contraindications: 2,3

  • Genitourinary abnormalities (congenital or acquired)
  • Empty or unidentifiable bladder
  • Bladder tumor
  • Lower abdominal scarring
  • Overlying infection
  • Bleeding disorders
  • Organomegaly

Complications: 2,3

  • Gross hematuria
  • Abdominal wall cellulitis
  • Bowel perforation

Equipment: 2,3

  • Lidocaine for local anesthesia (1% or 2%, with or without epinephrine)
  • Adhesive bandaid
  • Povidone-iodine or Chlorhexidine prep
  • 25g to 27g 1” needle
  • 22g or 23g 1.5” needle
  • Sterile 5ml and 10ml syringes

Procedure (ultrasound-guided): 2,3

  • Position the patient supine in frog-leg position, using parent or caregiver to assist with immobilization.
  • Using sterile technique, identify the bladder on ultrasound; it appears as an anechoic ovoid structure just below the abdominal musculature.
    • Landmarking: midline lower abdomen, just above the pubic symphysis
  • Mark the area and sterilize; infiltrate local anesthetic into the marked area
  • Insert the needle slightly cephalad, 10-20° off perpendicular while aspirating until urine appears.
  • If the insertion is unsuccessful, do not withdraw the needle fully. Instead, pull back until the needle tip rests in the subcutaneous tissue and then redirect 10° in either direction. Do not attempt more than 3 times.
  • One sufficient urine is obtained, withdraw the needle and place a sterile dressing at the site of the insertion.

 

 

From: Performing Medical Procedures – NEJM

 

References

    1. Contamination rates of different urine collection methods for the diagnosis of urinary tract infections in young children: an observational cohort study. Tosif S; Baker A; Oakley E; Donath S; Babl FE. J Paediatr Child Health. 2012; 48(8):659-64 (ISSN: 1440-1754). Retrieved from https://reference.medscape.com/medline/abstract/22537082 on December 10, 2017
    2. Suprapubic Aspiration. Alexander D Tapper, MD, Chirag Dave, MD, Adam J Rosh, MD, Syed Mohammad Akbar Jafri, MD. Medscape. Updated: Mar 31, 2017. Retrieved from https://emedicine.medscape.com/article/82964-overview#a4 on December 10, 2017
    3. Suprapubic Bladder Aspiration. Jennifer R. Marin, M.D., Nader Shaikh, M.D., Steven G. Docimo, M.D., Robert W. Hickey, M.D., and Alejandro Hoberman, M.D. N Engl J Med 2014; 371:e13September 4, 2014DOI: 10.1056/NEJMvcm1209888. Retrieved from http://www.nejm.org/doi/full/10.1056/NEJMvcm1209888 on December 10, 2017
    4. Suprapubic bladder aspiration versus urethral catheterization in ill infants: success, efficiency and complication rates. Pollack CV Jr, Pollack ES, Andrew ME. Ann Emerg Med. 1994 Feb;23(2):225-30. Retrieved December 10, 2017.
    5. Use of portable ultrasound to assist urine collection by suprapubic aspiration. Gochman RF1, Karasic RB, Heller MB. Ann Emerg Med. 1991 Jun;20(6):631-5. Retrieved December 10, 2017.

 

Other PEM PoCUS Videos Here

 

 

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RCP – Elb-‘ow’! Does my patient with an elbow injury require an x-ray?

Elb-‘ow’! Does my patient with an elbow injury require an x-ray?

Resident Clinical Pearl (RCP) – December 2017

Allyson Cornelis R1 FMEM, Dalhousie University, Saint John, New Brunswick

Reviewed by Dr. David Lewis

 

Why should you care?

Trauma to the upper extremity can result in injury to the various components of the elbow joint and associated anatomical structures. Important neurovascular structures associated with the elbow joint are the brachial artery, radial artery, ulnar artery, median, radial, and ulnar nerve¹. Elbow injuries causing fracture increase the likelihood of neurovascular damage. If fractures are missed, this may result in further damage and complications including prolonged functional limitations to the joint, nerve damage causing distal functional decline, and potential vascular compromise to the limb more distal to the injury.

Tintinalli’s Comprehensive Guide to Emergency Medicine.2

Functionally, the elbow has two primary movements: flexion/extension, and supination/pronation¹.

Fractures at the elbow may occur at the distal humerus (supracondylar, epicondylar, condylar, trochlea, and capitellum fractures), the proximal ulna (coronoid process, olecranon fractures), and the proximal radius (radial head fractures)¹. Of these, radial head fractures are the most common. Common mechanisms for these injuries include falling on an outstretched hand and direct blows to the elbow.

 

How do I know if my patient requires an X-ray for their elbow pain?

There is a rule for that! The elbow extension rule!

Simply stated: If a patient with an elbow injury is able to fully extend their elbow, they are unlikely to have a fracture and do not require imaging³.

The “how to”:

  1. Provide analgesia to patients
  2. Have patient seated with supinated arms
  3. Have patient flex shoulder to 90 degrees
  4. Ask patient to fully extend elbow to either the point of locking or the same level of extension as contralateral side

Of course, no rule is perfect, and the patient should be reassessed later if the following occur

  • Can no longer fully straighten elbow
  • Pain is getting worse
  • Cannot use their arm as previous

The patient should have imaging at the current visit if:

  • Patient is unreliable for follow up
  • If olecranon fracture is possible

 

The evidence³

Of 1740 patients presenting within 72 hours of traumatic elbow injury, 31% had a fracture³. In adults with the ability to fully extend their elbow following trauma, there was a 2% chance they had a fracture. In adults unable to fully extend their elbow following trauma, there was a 48% chance they had a fracture.

In children able to fully extend their elbow following trauma, there was a 4% chance they have a fracture, and in children unable to fully extend their elbow following trauma, there was a 43% chance they had a fracture³.

 

Bottom LinePatients presenting with elbow trauma and an inability to extend their elbow fully require radiography. Those able to fully extend their elbow do not require imaging unless follow up is unreliable, an olecranon fracture is suspected. Caution should be exercised with assessment in children.

 


Addendum: 

Consider adding PoCUS to your clinical assessment of elbow injuries. Elbow joint effusions are very easily visualized. The presence of a joint effusion in a patient with elbow pain following trauma is a significant finding and warrants further investigation with radiography. Some studies have shown PoCUS to be more sensitive than x-ray in diagnosing occult elbow fractures.

 

Download (PDF, 2.87MB)

 


References

(1) Appleboam, A., Reuben, AD., Benger, JR., Beech, F., Dutson, J., Haig, S., Lloyd, G. (2008). Elbow extension test to rule out elbow fracture: Multicentre, prospective validation and observational study of diagnostic accuracy in adults and children. British Medical Journal, 337:a2428.

(2) Tintinalli, JE. (2016). Cardiogenic Shock (8th ed.) Tintinalli’s Emergency Medicine: A Comprehensive Study Guide (pages 1816-1817). New York: McGraw-Hill.

(3) Sheehan, SE., Dyer, GS., Sodickson, AD., Ketankumar, IP., Khurana, B. (2013). Traumatic elbow injuries: What the orthopedic surgeon wants to know. Radiographics, 33(3), 869-884.

 

This post was copyedited by Kavish Chandra @kavishpchandra

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The 2018 Emergency Medicine Review Course

The Emergency Medicine Review (EM Review) course is offered by the Saint John Regional Hospital Emergency Department to guide eligible candidates in preparation for the CCFP (EM) licensing exam.
Over the 19 interactive sessions, a CCFP(EM) lecturer will review the CFPC’s Priority Topics in Emergency Medicine: the core material covered in the exam. A practice written exam and final oral exam are offered at the end of the course. Feedback is provided throughout. 

The EM Review 18 Course (interactive Course) is now full. If you would like to be placed on a waiting list for the self-directed stream only, please email us at info.emreview@gmail.com


We offer two streams to the EM Review Course:

  1. Interactive Stream – Cost: $2750:
    • Access to online sessions each Tuesday evening from 7-9pm. Includes access to recorded lectures, practice SAMPs, a practice exam, and a live practice oral exam session (5 cases).
    • We have strict registration caps on this stream to allow for adequate participant involvement each week

  1. Self- Directed Stream -Cost $2000:
    • Access to all online material, including recorded lectures, practice SAMPs, practice exam, and a live practice oral exam session (5 cases). Note: this stream does not include participation in the interactive sessions each week. Instead, the recordings are available for your viewing after each session.

Weekly Overview:

  • Practice Short Answer Management Problems (SAMPs) are sent for completion and self-marking one week prior to each session
  • Practice orals are completed by 1-2 participants while others review
  • Core material is presented in a case-based format with “SAMP-style”, interactive questioning

More Information Here

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EM Reflections – December 2017

Thanks to Dr Joanna Middleton for leading the discussion this month and providing these tips and references.

Edited by Dr David Lewis 

 

Top tips from this month’s rounds:

Incomprehensible Patient – Delirium or Aphasia?

Pediatric Trauma

CME QUIZ

 

Take Home Points

  • Sudden onset language impairment should be assumed to be aphasia until proven otherwise
  • Aphasia is most commonly caused by CVA and usually has associated lateralising motor signs (but not always)
  • Aphasic patients will be able to perform non-verbal tasks normally
  • If in doubt involve telestroke / neurology early
  • Global aphasia can have a catastrophic outcome on quality of life. In selected patients, early thrombolysis can significantly improve prognosis.
  • The injuries sustained by children in chest trauma are frequently different from adults
  • Signs of shock in pediatric trauma can be subtle
  • Use evidence based guidelines e.g PECARN when considering CT for abdominal trauma
  • Elevated Tropinin or abnormal ECG suggest blunt cardiac injury

 


Incomprehensible Patient – Delirium or Aphasia?

Both can present with disorders of speech and language, however it is important to rapidly distinguish aphasia due to it’s association with stroke and the benefits of early thrombolysis.

Delirium, also known as acute confusional state, is an organically caused decline from a previously baseline level of mental function. It often has a fluctuating course, attentional deficits, and disorganization of behaviour including speech and language.

Aphasia is an impairment of language, affecting the production or comprehension of speech and the ability to read or write. Aphasia is always due to injury to the brain, most commonly from a stroke, but also trauma, tumour or infection.

 

The first tip here is to figure out how to describe the features of a patient’s language. How is the patient’s language produced and understood?

Are the words clearly enunciated (favoring aphasia) or slurred (favoring delirium)?

Is the patient’s speech grammatically correct (delirium) or lacking in appropriate syntax (aphasia)?

Is the patient’s prosody—or pattern of speech—fluent (delirium) or irregular (aphasia)?

Can the patient understand spoken language (delirium) or is there a major difficulty with following simple verbal/written commands (aphasia)?

Naming and repetition should also be assessed as part of any neurologic examination, but impairment in these modalities is not as useful in distinguishing delirium from aphasia.

The motor evaluation of inattention in a delirious patient involves testing for asterixis, either with arms and wrists fully extended or having the patient squeeze the fingers of the examiner (the “milk maid’s sign”). A delirious patient will struggle with these tasks, the extended hands may flap or the fingers may intermittently lose their grip. The aphasic patient, in contrast, may not have trouble with this.

Speak of the devil: Aphasia vs. delirium

 

Global Aphasia

  • Severe impairment of production, comprehension and repetition of language
  • Usually large CVA of left MCA
  • Usually associated with extensive perisylvian injury affecting both Broca’s and Wernicke’s areas
  • Usually accompanied by right hemiparesis and often a right visual field deficit (in right handed pt)
  • Patients with global aphasia can be shown to perform normally on nonverbal tasks such as picture matching, demonstrating they are not suffering from confusion or dementia

 

Stroke Thrombolysis – Indications and Contraindications Reminder

Patient Selection for Thrombolytic Therapy in AIS:

Inclusion criteria: Patients  >18 years of age with symptoms of AIS and a measurable neurological deficit with time of onset <4.5 h.

Exclusion criteria:

A. History

  • History of intracranial hemorrhage
  • Stroke, serious head injury or spinal trauma in the preceding 3 months
  • Recent major surgery, such as cardiac, thoracic, abdominal, or orthopedic in previous 14 days
  • Arterial puncture at a non-compressible site in the previous 7 days
  • Any other condition that could increase the risk of hemorrhage after rt-PA administration

B. Clinical

  • Symptoms suggestive of subarachnoid hemorrhage
  • Stroke symptoms due to another non-ischemic acute neurological condition such as seizure with post-ictal Todd’s paralysis or focal neurological signs due to severe hypo- or hyperglycemia
  • Hypertension refractory to antihypertensives such that target blood pressure <185/110 cannot be achieved
  • Suspected endocarditis

C. Laboratory

  • Blood glucose concentration below 2.7 mmol/L or above 22.2 mmol/L
  • Elevated activated partial-thromboplastin time (aPTT)
  • International Normalized Ratio (INR) greater than 1.7
  • Platelet count <100 x 109/L
  • Current use of direct thrombin inhibitors or direct factor Xa inhibitors with elevated insensitive global coagulation tests (aPTT for dabigatran, INR for rivaroxaban) or a quantitative test of drug activity (Hemoclot® for dabigatran, specific anti-factor Xa activity assays for rivaroxaban, apixaban and edoxaban). In this situation, endovascular treatment (thrombectomy) should be considered if patient eligible.

D. CT or MRI Findings

  • Any hemorrhage on brain CT or MRI
  • CT showing early signs of extensive infarction (hypodensity more 1/3 of cerebral hemisphere), or a score of less than 5 on the Alberta Stroke Program Early CT Score [ASPECTS], or MRI showing an infarct volume greater than 150 cc on diffusion-weighted imaging.

Relative contraindications for rt-PA therapy in AIS include the following:

  • Recent myocardial infarction with suspected pericarditis
  • Rapidly improving stroke symptoms
  • Pregnancy or post-partum period
  • Recent GI or urinary tract hemorrhage (within 21 days)

From Thrombosis Canada

Take Home Points

  • Sudden onset language impairment should be assumed to be aphasia until proven otherwise
  • Aphasia is most commonly caused by CVA and usually has associated lateralising motor signs (but not always)
  • Aphasic patients will be able to perform non-verbal tasks normally
  • If in doubt involve telestroke / neurology early
  • Global aphasia can have a catastrophic outcome on quality of life. In selected patients, early thrombolysis can significantly improve prognosis.

 


Pediatric Trauma

Some specific issues particular to pediatric trauma are highlighted:

Pediatric Chest Trauma

Children have compliant chests and thus sustain musculoskeletal thoracic injuries far less frequently (5% of traumas). However, due to this elasticity, the most common injury is a pulmonary contusion.

PITFALLS

Don’t expect traditional adult injury findings: Absence of chest tenderness, crepitus and flail chests does not preclude injury.

Bendy ribs – injury to internal organs with little external evidence

Lung contusions ~50% of chest trauma

Force transmitted to lung parenchyma – lung lacerations much less common <2%

 

Pediatric Abdominal Trauma

Beware: 20-30% of pediatric trauma patients with a “normal” abdominal exam will have significant abdominal injuries on imaging.

Any polytrauma patient with hemodynamic instability should be considered to have a serious abdominal injury until proven otherwise. Tachycardia primary reflex for kids in response to hypovolemia and it may be the only sign of shock.

HIGH RISK – Indications for CT

• History that suggests severe intra-abdominal injury e.g abrupt acceleration/deceleration, pedestrian vs vehicle, handlebar injury, fall from horse etc

• Concerning physical – tenderness, peritoneal signs, seatbelt sign or other bruising

• AST >200 or ALT >125

• Decreasing Hb or Hct

• Gross hematuria

• Positive FAST

PECARN 

The Pediatric Emergency Care Applied Research Network (PECARN) network derived a clinical prediction rule to identify children (median age, 11 years) with acute blunt torso trauma at very low risk for having intra-abdominal injuries (IAIs) that require acute intervention.

The prediction rule consisted of (in descending order of importance)

  • no evidence of abdominal wall trauma or seat belt sign
  • Glasgow Coma Scale score greater than 13
  • no abdominal tenderness
  • no evidence of thoracic wall trauma
  • no complaints of abdominal pain
  • no decreased breath sounds
  • no vomiting

The rule had a negative predictive value of 5,028 of 5,034 (99.9%; 95% confidence interval [CI] 99.7% to 100%), sensitivity of 197 of 203 (97%; 95% CI 94% to 99%), specificity of 5,028 of 11,841 (42.5%; 95% CI 41.6% to 43.4%), and negative likelihood ratio of 0.07 (95% CI 0.03 to 0.15).

Holmes JF et al. Identifying children at very low risk of clinically important blunt abdominal injuries. Ann Emerg Med 2013 Feb 4; [e-pub ahead of print]. (http://dx.doi.org/10.1016/j.annemergmed.2012.11.009)

 

Blunt Cardiac Injury

Largest pediatric case series of BCI – 184 patients – 95% had simple cardiac contusions. https://www.ncbi.nlm.nih.gov/pubmed/8577001

The clinical presentation of blunt cardiac injury varies. Mild injuries may present without objective findings, while some patients may have minor dysrhythmias.

A normal ECG and troponin I during the first 8 hours of hospital stay rules out blunt cardiac injury, and the negative predictive value of combining these 2 simple tests was 100%. https://www.ncbi.nlm.nih.gov/pubmed/12544898

 

Click image to link to full article

 

Traumatic Tricuspid Injuries

Location, location, location

RV posterior to sternum – blunt force elevates pressures resulting in rupture of chordae, papillary muscle injury or tear of leaflet

Most frequent associated injury:  pulmonary contusion

“The presence of a transient right bundle branch block in the setting of myocardial contusion is a described, but under-recognized occurrence.”

“Although an rsr’ in the right precordial leads may be normal in children, it’s combination with an abnormal frontal axis (“bifasicular block”) is always abnormal and suggest injury to the RV”

 

Episode 95 Pediatric Trauma

Take Home Points

  • The injuries sustained by children in chest trauma are frequently different from adults
  • Signs of shock in pediatric trauma can be subtle
  • Use evidence based guidelines e.g PECARN when considering CT for abdominal trauma
  • Elevated Tropinin or abnormal ECG suggest blunt cardiac injury

 


CME QUIZ

EM Reflections - Dec 17 - CME Quiz

EM Reflections – Dec 17 – CME Quiz

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EM Reflections – November 2017

Thanks to Dr Paul Page for leading the discussion this month

Edited by Dr David Lewis 

Top tips from this month’s rounds:

  1. Managing violent behaviour in the Emergency Department

  2. Early CT can miss delayed onset subdural hematoma after head trauma

  3. Posterior shoulder dislocation can be missed if not specifically ruled out

  4. CME QUIZ

 


Managing violent behaviour in the Emergency Department

Workplace violence is unfortunately a common problem for Emergency Department staff.

Violence in the ED Reaches a Crisis Point

Not only is the environment high risk for exacerbating behavioural extremes but there are also a wide range of medical and psychiatric conditions that may present with violence and aggression.

Causes and associations with violence and aggressive behaviour in the ED:

Medical

  • Hypoxia
  • Hypoglycemia
  • Hypothermia
  • Metabolic
    • Pancreatitis, hepatic encephalopathy, hyponatremia, etc
  • Sepsis
    • UTI, meningitis, encephalitis, pneumonia, etc
  • Toxic
    • Alcohol, drugs, etc
  • Seizure, post ictal
  • Stroke
  • Dementia
  • Brain tumour
  • Head injury

Psychiatric

  • Schizophrenia
  • Bipolar
  • Panic disorder, antisocial personality disorder, mood disorder, etc

Environment

  • Overcrowding
  • Police custody, gang violence, etc

 

Excellent article on managing behavioural emergencies in the emergency dept from LitFL:

Behavioural Emergencies

 

Restraint

The CMPA provides medicolegal guidance on the use of restraint:

When there’s a possibility that patients may harm themselves or others, physical or chemical restraint may be required.

When using restraints physicians should consider the following risk management measures, which are based on the experts’ opinions in the analyzed CMPA cases:

  • Attempt to de-escalate the situation using other methods.
  • Obtain an adequate history, including medications and co-morbidities.
  • Conduct an appropriate physical examination.
  • Explain the plan for the use of restraints calmly and clearly to patients or substitute decision-makers.
  • Document the rationale for using restraints and use the least restrictive means necessary.
  • Ensure clear and readily available policies and procedures for monitoring restrained patients and ensure appropriate training of staff.
  • Adhere to applicable regulations, laws, and accreditation standards.

 

The National Institute of Clinical Excellence (NICE UK) provides guidance on the use of rapid tranquillisation:

Download (PDF, 62KB)

 

More Information and lInks:

Horizon Health Work Place Violence Prevention Policy: HHN-SA-012

ACEP – Emergency Department Violence Fact Sheet

Augusta University – Violence in ED Manual – violenceinedmanual

 


Reliability of Early CT in Head Injury

Modern CT is highly sensitive in the diagnosis of traumatic brain injury, including subdural and epidural hematoma following head trauma.

 

 

The medical literature contains reports of false negative early CT following minor head injury, however in this review, they were rare (3 adverse outcomes in 65,000 cases), hence their recommendation:

 

The strongest scientific evidence available at this time would suggest that a CT strategy is a safe way to triage patients for admission.

http://emj.bmj.com/content/22/2/103

Case reports of delayed diagnosis of subdural / epidural hematoma following normal CT scan 

http://www.sciencedirect.com/science/article/pii/S0196064494701156

http://thejns.org/doi/abs/10.3171/jns.1985.63.1.0030

 

In patients who present, following head trauma, with persistent symptoms despite initially normal head CT, repeat imaging with MRI is recommended.

Symptoms of subdural hematoma

  • slurred speech.
  • loss of consciousness or coma.
  • seizures.
  • numbness.
  • severe headaches.
  • weakness.
  • visual problems.

 

 


Posterior shoulder dislocation can be missed if not specifically ruled out

 

Posterior shoulder dislocation is less common than anterior dislocation. It is a commonly missed diagnosis in the Emergency Department. It can occur following trauma and should be specifically considered following seizure / electric shock.

The patient present with shoulder pain and reduced range of movement. The shoulder / arm is adducted and internally rotated.

A single AP shoulder radiograph is unreliable, but may show the ‘lightbulb sign’. The axillary lateral is usually diagnostic but may be not be possible due to pain.

Posterior shoulder dislocation should be considered in all patients where the axillary lateral was impossible to perform due to pain and immobility. A scapular Y view should be performed

 

AP Shoulder – Lightbulb sign – posterior dislocation – due to internally rotated humeral head

 

AP Shoulder – posterior dislocation (more subtle appearance) – malalignment of joint line

 

 

Axillary view – posterior dislocation

 

Scapular Y view – posterior dislocation

 

Point of Care Ultrasound

Ultrasound can be very useful for diagnosing shoulder dislocation and can be performed quickly prior to formal radiography. The transducer is placed in a transverse orientation, posteriorly, just below the scapular spine. Move laterally to the joint.

 

 

 

 

In comparison to radiography, US had a sensitivity of 100.0%, specificity of 80.0%, positive predictive value of 98.7%, and negative predictive value of 100.0% in diagnosis of shoulder dislocation. The specificity of US in diagnosis of proper reduction of the joint, was estimated to be 98.7% with a negative predictive value of 100.0%. US took a significantly less time than radiography to be performed (p < 0.001).

http://www.sciencedirect.com/science/article/pii/S2452247317300791

 

 



 

CME QUIZ

EM Reflections - Nov 17 - CME Quiz

EM Reflections – Nov 17 – CME Quiz

 

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RCP – Animal Bites

Animal Bites

Resident Clinical Pearl (RCP) – November 2017

Renée Amiro, R1 FMEM, Dalhousie University, Saint John, New Brunswick

Reviewed by Dr. David Lewis

 

Mr. Stark brings in his 8-year-old adopted son, Jon Snow, to the emergency room on Christmas day. Jon had just received a puppy, Ghost, as a Christmas present that morning. Jon, who knows nothing (about raising puppies), was playing too rough with the pup and got a bite on his right hand.

How do we appropriately manage this animal bite in the emergency room?

Management

When a patient presents to the ED with an animal bite, the factors in management that need to be addressed are:

  1. How to properly care for the wound
  2. Is antibiotic prophylaxis needed?
  3. Does the wound require closure with sutures?
  4. When does a bite require surgical consultation?
  5. When should you worry about tetanus and rabies?

 

Caring for the wound

Managing an animal bite has much of the same principles of usual good wound care

  1. Control hemorrhage
  2. Preform a neurovascular assessment
  3. Clean the wound meticulously. This is very important in animal and human bites. To reduce the number of bacteria, the wound should be flushed with copious amounts of saline or water

Local anesthetic should be used to reduce pain and facilitate cleaning. The wound should also be inspected for foreign bodies. Bites overlying joints should be put through their entire range of motion (bone, tendon or joint capsule involvement). If you suspect a foreign body but can’t see it, get an x-ray.

Pearl: for puncture wounds (cats are the biggest perpetrators), the same principles of wound care apply except superficially irrigate wounds and do not use high pressure

 

Is antibiotic prophylaxis needed?

Most bites to not require prophylactic antibiotics. There are some high-risk wounds that do. Those include:

  1. Deep puncture wounds (think cats)
  2. Associated crush injury
  3. Injury in areas overlying venous or lymphatic compromise
  4. Primary closure of the wound
  5. Wounds on hands, genitals or overlying joints
  6. Host factors: immunocompromised, diabetes

Table of prophylactic antibiotic choices. Duration of therapy depends on the antibiotic choice.

Ellis and Ellis. Am Fam Physician. 2014 Aug 15;90(4):239-243.

 

Does the wound requires closure with sutures

Generally, no, especially if cats are the perpetrators. But if cosmetic concerns arise, wounds should meet all the following criteria before primary closure:

  1. Clinically uninfected
  2. < 12 hrs old (<24 hrs on the face)
  3. NOT located on the hand or the foot

The wound should NOT be closed primarily if the following criteria are met:

  1. Crush injuries
  2. Hand and foot wounds
  3. Deep puncture wounds
  4. Cat or human wounds
  5. Immunocompromised host
  6. >12 hrs old

 

When does a bite require surgical consultation?

If the injury results in complex facial wounds, neurovascular compromise, osteomyelitis or joint infection or deep wounds that penetrate underlying structures (joint, bone, tendon), get a surgical consultation.

That being said, consider consultation with any deep wound on the hand.

 

When do I worry about tetanus and rabies prophylaxis?

When considering tetanus prophylaxis, the decision to intervene is the same in non-bite wounds.

   Ellis and Ellis. Am Fam Physician. 2014 Aug 15;90(4):239-243.

 

For rabies, post-exposure prophylaxis is generally not needed in patients with a dog or cat bite as long as the animal is not showing signs of rabies: dysphagia, abnormal behaviour, paralysis, seizures and ataxia.

Ellis and Ellis. Am Fam Physician. 2014 Aug 15;90(4):239-243.

 

Bottom Line: Animal bites, like other wounds, require regular wound care with a focus on meticulous cleaning. Cat bites usually need prophylactic antibiotics, dogs usually do not. All immunocompromised hosts get prophylactic antibiotics

 

References

  1. Baddour, L. and Sexton, D. Soft tissue infections due to dog and cat bites. Retrieved from https://www.uptodate.com/contents/soft-tissue-infections-due-to-dog-and-cat-bites. Accessed August 1, 2017.
  2. Callaham, M. Controversies in antibiotic choices for bite wounds. Ann Emerg Med 1988; 17:1321.
  3. Ellis, R. and Ellis, C. Am Fam Physician. 2014 Aug 15;90(4):239-243.

 

This post was copyedited by Kavish Chandra @kavishpchandra

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New SJRHEM Dalhousie Course – Debriefing Skills for Simulation – The Basics

New SJRHEM Dalhousie Course – Debriefing Skills for Simulation – The Basics

When Is It?

8th-9th February 2018

Who is this for?

If you are interested in using simulation for education in healthcare, then this is for you! We aim to give you the basic skills needed to start debriefing in your own institution. This is a practical course with lots of opportunities to debrief.

 

 

Download (PDF, 260KB)

 

 

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RCP – Dental Block, ER Doc

Another Solution for Dental Pain when “NSAIDs do nothing for me Doc!

Resident Clinical Pearl (RCP) – Guest Resident Edition

Peter Leighton,  R3 FMEM 2+1, Dalhousie University, Halifax

Reviewed by Dr. David Lewis

 

Dental pain is a common problem encountered in the Emergency Department (ED), yet physicians in the ED often have no to little education regarding management of dental pain. Depending on where you read, dental pain complaints account for 1-5% of emergency department visits. A common approach consists of looking for infection and providing a prescription for antibiotics and NSAIDs along with recommendation to follow up with a dentist. Although, there is good evidence for NSAIDs in dental pain, some patients find that it does not help enough with their pain or they have contraindications to NSAIDs. This often leads to the prescription of opioids for dental pain. Given the recent opioid crisis in Canada, there has been a search for other forms of management of toothache/dental pain in the ED. Insert the dental block! It’s fast, easy, and provides good pain relief, while providing a chance for patients to book an appointment to see their dentist the following day. There has been some evidence that this method achieves good pain control for the patient and may help lower opioid prescriptions in the ED for dental pain.

There are essentially 2 blocks you will need to know:

  • The Inferior Alveolar Nerve Block (Mandibular teeth)
  • Supraperiosteal Infiltrations (Maxillary teeth)

Indications

  • Dental abscess
  • Toothache
  • Pulpitis
  • Root impaction
  • Dry socket
  • Post-extraction pain
  • Trauma – lacerations, fractures

Contraindications

  • Allergy to local anesthetic
  • Distortion of landmark
  • Uncooperative patient
  • Injecting through infected tissue – may cause bacteremia
  • Cardiac congenital abnormalities and mechanical valves – require prophylaxis for endocarditis
  • Coagulopathy

What you will need

  • Syringe
  • Needle – 25-27 gauge and 1.5 inch
  • Lidocaine with epinephrine (max dose 7 mg/kg)
  • Bupivicaine +/- epinephrine (max dose 2 mg/kg)
  • Non-sterile gloves
  • Suction and light source may be required

 

The combination of Lidocaine and Bupivicaine allow the mix of immediate analgesia from the Lidocaine and prolonged duration of action by the Bupivicaine. The addition of Epinephine will also increase duration of effect. This combination should provide approximately 8 or more hours of anesthetic effect.

 

Technique:

Supraperiosteal Infiltration

Pull out patient’s cheek laterally to have a good view of the patient’s tooth and gingiva. Insert needle into the mucobuccal fold just above the apex of the tooth to be anesthetized. Keep the needle parallel to the tooth and insert it a few millimeters until needle tip is above the apex of the tooth. If bone is contracted, withdraw 1-2mm and aspirate. If no blood is aspirated then inject 1-2 ml of anesthetic. If blood is aspirated then withdraw and reposition.

 

From: www.ebmedicine.net – click here for full article

 


 

Inferior Alveolar Nerve Block

Place your thumb in the coronoid (mandibular) notch of the patient and extend the patient’s cheek out laterally so you can see the patient’s pterygomandibular raphe. Place your syringe in the opposite corner of the mouth and with your needle at the middle level of the raphe, aim just lateral to the raphe. Insert your needle approx. 2-2.5cm until you hit bone. Pull back a millimeter and aspirate twice. If any blood on aspiration, withdraw and reposition more laterally. If no blood with aspiration then inject 1-2ml of anesthetic.

 

From: Jason Kim’s Blog – click here for full article

 

 

From: www.ebmedicine.net – click here for full article

 


 

Videos:

Please see the dentistry videos below to review anatomical landmarks of both techniques:

 

Supraperiosteal technique

 

Inferior Alveolar Block

 


 

References

 

  1. Complications, diagnosis, and treatment of odontogenic infections [Internet]; c2017 [cited 2017 November 10]. Available from: https://www.uptodate.com/contents/complications-diagnosis-and-treatment-of-odontogenic-infections?source=search_result&search=dental%20pain&selectedTitle=1~150.
  2. Fixing Faces Painlessly: Facial Anesthesia In Emergency Medicine [Internet]; c2017 [cited 2017 November 12]. Available from: https://www.ebmedicine.net/topics.php?paction=showTopicSeg&topic_id=207&seg_id=4229
  3. Fox TR, Li J, Stevens S, Tippie T. A performance improvement prescribing guideline reduces opioid prescriptions for emergency department dental pain patients. Annals of Emergency Medicine 2013;62(3):237-40.
  4. IA with a Short Needle [Internet]; c2015 [cited 2017 November 10]. Available from: https://www.youtube.com/watch?v=1Mf3f0XmsqI.
  5. 5. Local Infiltration [Internet]; c2014 [cited 2015 November 10]. Available from: https://www.youtube.com/watch?v=Y2NSuxd7j_g.
  6. How I learned to love dental blocks [Internet]; c2014 [cited 2017 November 10]. Available from: http://www.clinicaladvisor.com/the-waiting-room/dental-blocks-useful-in-emergency-medicine/article/382951/.
  7. M2E Too! Mellick’s Multimedia EduBlog [Internet]; c2014 [cited 2017 November 10]. Available from: http://journals.lww.com/em-news/blog/M2E/pages/post.aspx?PostID=32.
  8. Moore PA, Hersh EV. Combining ibuprofen and acetaminophen for acute pain management after third-molar extractions: Translating clinical research to dental practice. J Am Dent Assoc 2013 Aug;144(8):898-908.
  9. Okunseri C, Dionne RA, Gordon SM, Okunseri E, Szabo A. Prescription of opioid analgesics for nontraumatic dental conditions in emergency departments. Drug Alcohol Depend 2015 Nov 1;156:261-6.
  10. Patel NA, Afshar S. Addressing the high rate of opioid prescriptions for dental pain in the emergency department. Am J Emerg Med 2017 Jul 3.
  11. Oral Nerve Block [Internet]; c2016 [cited 2017 November 10]. Available from: https://emedicine.medscape.com/article/82850-overview#a1.
  12. Dental Pain in the ED: Big Solution in a Small Package [Internet]; c2005 [cited 2017 November 10]. Available from: http://journals.lww.com/em-news/Fulltext/2005/06000/Dental_Pain_in_the_ED__Big_Solution_in_a_Small.12.aspx.

 

 

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SJRHEM Journal Club Report Oct 2017

SJRHEM Journal Club Report Oct 2017

Allyson Cornelis, R1 iFMEM

Hosted by Dr Andrew Lohoar


Abstract:

Idarucizumab for Dabigatran Reversal — Full Cohort Analysis

Charles V. Pollack, Jr., M.D., Paul A. Reilly, Ph.D., Joanne van Ryn, Ph.D., John W. Eikelboom, M.B., B.S., Stephan Glund, Ph.D., Richard A. Bernstein, M.D., Ph.D., Robert Dubiel, Pharm.D., Menno V. Huisman, M.D., Ph.D., Elaine M. Hylek, M.D., Chak-Wah Kam, M.D., Pieter W. Kamphuisen, M.D., Ph.D., Jörg Kreuzer, M.D., Jerrold H. Levy, M.D., Gordon Royle, M.D., Frank W. Sellke, M.D., Joachim Stangier, Ph.D., Thorsten Steiner, M.D., Peter Verhamme, M.D., Bushi Wang, Ph.D., Laura Young, M.D., and Jeffrey I. Weitz, M.D.

N Engl J Med 2017; 377:431-441August 3, 2017DOI: 10.1056/NEJMoa1707278

 

BACKGROUND
Idarucizumab, a monoclonal antibody fragment, was developed to reverse the anticoagulant effect of dabigatran.

METHODS
We performed a multicenter, prospective, open-label study to determine whether 5 g of intravenous idarucizumab would be able to reverse the anticoagulant effect of dabigatran in patients who had uncontrolled bleeding (group A) or were about to undergo an urgent procedure (group B). The primary end point was the maximum percentage reversal of the anticoagulant effect of dabigatran within 4 hours after the administration of idarucizumab, on the basis of the diluted thrombin time or ecarin clotting time. Secondary end points included the restoration of hemostasis and safety measures.

RESULTS
A total of 503 patients were enrolled: 301 in group A, and 202 in group B. The median maximum percentage reversal of dabigatran was 100% (95% confidence interval, 100 to 100), on the basis of either the diluted thrombin time or the ecarin clotting time. In group A, 137 patients (45.5%) presented with gastrointestinal bleeding and 98 (32.6%) presented with intracranial hemorrhage; among the patients who could be assessed, the median time to the cessation of bleeding was 2.5 hours. In group B, the median time to the initiation of the intended procedure was 1.6 hours; periprocedural hemostasis was assessed as normal in 93.4% of the patients, mildly abnormal in 5.1%, and moderately abnormal in 1.5%. At 90 days, thrombotic events had occurred in 6.3% of the patients in group A and in 7.4% in group B, and the mortality rate was 18.8% and 18.9%, respectively. There were no serious adverse safety signals.

CONCLUSIONS
In emergency situations, idarucizumab rapidly, durably, and safely reversed the anticoagulant effect of dabigatran. (Funded by Boehringer Ingelheim; RE-VERSE AD ClinicalTrials.gov number, NCT02104947.)

 

http://www.nejm.org/doi/full/10.1056/NEJMoa1707278

 


SJRHEM Journal Club Report

 

Download (PDF, 89KB)

 

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What we missed in FOAM October 2017

Welcome to SJRHEM’s newest feature, “Best of FOAM”. This is a quick curated list of the best free open access medical education the internet has to offer!

Subscribe to our twitter feed for regular updates and enjoy!

 

EM procedures

 

Clinical summaries

 

Kavish Chandra, R3 FMEM, Dalhousie University, Saint John, New Brunswick

 

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RCP – Aortic Dissection

Aortic Dissection

Resident Clinical Pearl (RCP) – October 2017

Luke Taylor, R2 FMEM, Dalhousie University, Saint John, New Brunswick

Edited by Dr Kavish Chandra – @kavishpchandra

Reviewed by Dr. David Lewis

 

Why should we care?

  • Aortic dissection remains difficult to diagnosis despite improvements in our understanding of the process and its characteristic features
  • Many cases are still missed at the initial ED presentation
  • Dissections occur after some violation of the intimal layer allows blood to enter the media and dissect between the intimal and adventitia. The blood flow entering the tear can extend the dissection proximally, distally, or both
  • With each hour that passes there is a 1-2% increase in mortality as the dissection extends

 

History

The presentation is similar across all acute aortic syndromes (AAS)

  • Acute intense chest or back pain (“SAH” of the torso)
  • Ask about:
    • Location
    • Intensity at onset
    • Radiation of pain
  • Aortic dissection can be painless ~5% of the time

IRAD 12 features most associated with acute aortic dissection

  • The characteristic tearing/ripping was not found to be a common descriptor in International Registry of Aortic Dissection (IRAD)

Pear: When assessing a patient with chest pain (CP), think CP+ 1 (see EMCases episode 92)

  • CP+ CVA
  • CP+ paralysis
  • CP+ hoarseness
  • CP+ limb ischemia

These features should drastically increase your suspicion for dissection

 

Physical examination

  • Keep in mind a large portion of general population have a BP differential >10mmHg
  • Vital signs can be normal but patients may have variation in their pulse or BP in the form a pulse deficit, SBP differential, hypertension or hypotension
    • Pulse Deficit: feel for difference between heart rate and the pulse rate
  • Murmur of aortic insufficiency:
    https://www.youtube.com/watch?v=aGLTJduxwvw
  • Neurological findings: objective focal neurological deficit

 

Investigations

  • CXR: Look for a wide mediastinum, loss of aortic knob, calcium sign
    • A normal CXR does not rule out aortic dissection as 1/3 of CXRs in aortic dissection are normal
    • Pearl : Measure the distance from the white line to the outer edge of the aortic knob. A distance >0.5cm is considered a 

positive calcium sign

https://radiopaedia.org/articles/tangential-calcium-sign

 

  • POCUS: If attempting, look for a dissection flap in the parasternal long axis view above the aortic valve. The flap may also be visible in abdominal aorta
    • Low sensitivity, but high specificity

  • Look for pericardial effusion from a retrograde dissection into the pericardium

http://rubble.heppell.net/chestnet/t/ecgtut.htm

 

 

 

FOAMED Links and Resources

http://edeblog.com/2014/02/pocus-for-aortic-dissection-a-case-2/

https://emergencymedicinecases.com/aortic-dissection-em-cases-course/

http://circ.ahajournals.org/content/112/24/3802

https://lifeinthefastlane.com/collections/ebm-lecture-notes/aortic-dissection/

https://first10em.com/2017/02/07/d-dimer-aortic-dissection/

 

This post was copyedited by Kavish Chandra @kavishpchandra

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