EM Reflections – September 2017

Thanks to Dr Paul Page for leading the discussion

Edited by Dr David Lewis

Top tips from this month’s rounds:

  1. Non-specific Abdo pain – Appendicitis is always high on the differential 

  2. Intoxicated patients are at high risk for Head Injury

  3. Acute Heart Failure has a higher mortality than acute NSTEMI

  4. Enhancing Morbidity and Mortality Rounds Quality


Non-specific Abdo pain – Appendicitis is always high on the differential 

Does a normal white count exclude appendicitis?No – Clinicians should be wary of reliance on either elevated temperature or total WBC count as an indicator of the presence of appendicitis. The ROC curve suggests there is no value of total WBC count or temperature that has sufficient sensitivity and specificity to be of clinical value in the diagnosis of appendicitis. Acad Emerg Med. 2004 Oct;11(10):1021-7.Clinical value of the total white blood cell count and temperature in the evaluation of patients with suspected appendicitis.

Does a normal CRP exclude appendicitis?No – Acad Emerg Med. 2015 Sep;22(9):1015-24. doi: 10.1111/acem.12746. Epub 2015 Aug 20. Accuracy of White Blood Cell Count and C-reactive Protein Levels Related to Duration of Symptoms in Patients Suspected of Acute Appendicitis.

 

A useful review on the diagnosis of appendicitis – JAMA. 2007 Jul 25; 298(4): 438–451. Does This Child Have Appendicitis?

 

Summary of Accuracy of Symptoms

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Summary of Accuracy of Signs

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Finally – Don’t forget Emergency Physicians can learn how to use Point of Care Ultrasound (PoCUS – ?Appendicitis) which can significantly improve diagnostic accuracy in experienced hands. Experience comes with practice.

J Med Radiat Sci. 2016 Mar; 63(1): 59–66. Published online 2016 Jan 20. doi:  10.1002/jmrs.154
Ultrasound of paediatric appendicitis and its secondary sonographic signs: providing a more meaningful finding

See SJRHEM PoCUS Quick Reference

PoCUS – Measurements and Quick Reference

 


Intoxicated patients are at high risk for Head Injury

Intoxicated patients with minor head injury are at significant risk for intracranial injury, with 8% of intoxicated patients in our cohort suffering clinically important intracranial injuries. The Canadian CT Head Rule and National Emergency X-Radiography Utilization Study criteria did not have adequate sensitivity for detecting clinically significant intracranial injuries in a cohort of intoxicated patients.

ACADEMIC EMERGENCY MEDICINE 2013; 20:754–760. Traumatic Intracranial Injury in Intoxicated Patients With Minor Head Trauma

Canadian CT Head Rule not applicable to intoxicated patients (GCS<13)

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CMPA provide useful guidance on the duties expected in the management of intoxicated ED patients.

 

All intoxicated patients, even the so called ‘frequent fliers’ require a full assessment, including history (from 3rd parties if available), full examination (especially neurological), blood glucose level, neurological observations, and this assessment should be carefully documented.

 

Can we defer CT imaging for intoxicated patients presenting with possible brain injury?

This study suggests that deferring CT imaging while monitoring improving clinical status in alcohol-intoxicated patients with AMS and possible ICH is a safe ED practice. This practice follows the individual emergency physician’s comfort in waiting and will vary from one physician to another.

http://www.sciencedirect.com/science/article/pii/S0735675716306805

 

Download (PDF, 172KB)

 

 


Acute Heart Failure has a higher mortality than acute NSTEMI

Cardiac markers are routinely used to exclude NSTEMI in patient presenting with chest pain. However the diagnosis of acute heart failure (AHF) is mainly clinical, including CXR, ECG, PoCUS.

Ultrasound B Lines and Heart Failure

 

There is good evidence that BNP can be helpful in ruling out AHF – BMJ 2015;350:h910

Recommended Link – Emergency Medicine Cardiac Research and Education Group

Download (PDF, 1.32MB)

 

 

Emergency Treatment of Acute Congestive Heart Failure

Most recent recommendations from Canadian Cardiovascular Society (2012)

  • 1 – We recommend supplemental oxygen be considered for patients who are hypoxemic; titrated to an oxygen saturation > 90% (Strong Recommendation, Moderate-Quality Evidence).

Values and preferences. This recommendation places relatively higher value on the physiologic studies demonstrating potential harm with the use of excess oxygen in normoxic patients and less value on long-term clinical usage of supplemental oxygen without supportive data.

  • 2 – We recommend CPAP or BIPAP not be used routinely (Strong Recommendation, Moderate-Quality Evidence).

Values and preferences. This recommendation places high weight on RCT data with a demonstrated lack of efficacy and with safety concerns in routine use. Treatment with BIPAP/CPAP might be appropriate for patients with persistent hypoxia and pulmonary edema.

  • 3 – We recommend intravenous diuretics be given as first-line therapy for patients with congestion (Strong Recommendation, Moderate-Quality Evidence).
  • 4 – We recommend for patients requiring intravenous diuretic therapy, furosemide may be dosed intermittently (eg, twice daily) or as a continuous infusion (Strong Recommendation, Moderate-Quality Evidence).
  • 5 – We recommend the following intravenous vasodilators, titrated to systolic BP (SBP) > 100 mm Hg, for relief of dyspnea in hemodynamically stable patients (SBP > 100 mm Hg):
    • i

      Nitroglycerin (Strong Recommendation, Moderate-Quality Evidence);

    • ii

      Nesiritide (Weak Recommendation, High-Quality Evidence);

    • iii

      Nitroprusside (Weak Recommendation, Low-Quality Evidence).

Values and preferences. This recommendation places a high value on the relief of the symptom of dyspnea and less value on the lack of efficacy of vasodilators or diuretics to reduce hospitalization or mortality.

  • 6 – We recommend hemodynamically stable patients do not routinely receive inotropes like dobutamine, dopamine, or milrinone (Strong Recommendation, High-Quality Evidence).

Values and preferences. This recommendation for inotropes place high value on the potential harm demonstrated when systematically studied in clinical trials and less value on potential short term hemodynamic effects of inotropes.

  • 7 – We recommend continuation of chronic β-blocker therapy with AHF, unless the patient is symptomatic from hypotension or bradycardia (Strong Recommendation, Moderate-Quality Evidence).

Values and preferences. This recommendation places higher value on the RCT evidence of efficacy and safety to continue β-blockers, the ability of clinicians to use clinical judgement and lesser value on observational evidence for patients with AHF.

  • 8 – We recommend tolvaptan be considered for patients with symptomatic or severe hyponatremia (< 130 mmol/L) and persistent congestion despite standard therapy, to correct hyponatremia and the related symptoms (Weak Recommendation, Moderate-Quality Evidence).

Values and preferences. This recommendation places higher value on the correction of symptoms and complications related to hyponatremia and lesser value on the lack of efficacy of vasopressin antagonists to reduce HF-related hospitalizations or mortality.

 

Emergency Medicine Cases – Episode 4: Acute Congestive Heart Failure 

In Summary

  • AHF is a serious life-threatening condition in its own right, excluding NSTEMI does not change that. Appropriate management and disposition (almost always admission) is required.
  • Oxygen and intravenous Diuretics are the first-line  treatment
  • Nitrates are recommended in the relief of dyspnea in hemodynamically stable patients (SBP > 100 mm Hg)

 


Enhancing Morbidity and Mortality Rounds Quality

The Ottawa M&M Model

CalderMM-Rounds-Guide-2012

 

 

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“Double double” yellow lines for improved road safety!

When it comes to reducing road deaths and injuries in New Brunswick, perhaps we should be inspired by Voltaire to avoid letting “the perfect be the enemy of the good.” Most serious collisions on our roads result from a combination of problems with road conditions, human factors, technology, and chance. While public safety campaigns and legislation try to affect many of the human factors by highlighting the dangers of distracted driving, intoxication (a subject for another day), and speed; and car manufacturers continue to improve vehicle safety; there is strong evidence that as a society, through improved regulations, we can also save lives by simple changes to road conditions and layout.

According to the world report on road traffic injury prevention, the Dutch policy of sustainable safety divides roads into one of three types according to their function, and then sets speed limits and driving conditions accordingly. These categories are Flow Roads; Distributor Roads; and Residential Roads. For Residential Roads, the needs of non-motorized users take priority, with the use of sidewalks, cycle lanes, crosswalks and slow speed limits. Distributor Roads carry traffic to and from large urban districts, and give equal importance to motorized and non-motorized local traffic, but separate users wherever possible, with variable speed limits. Flow Roads, or arterial roads and highways, are designed to allow through-traffic to go from the place of departure to the destination without interruption. Speed limits are higher, and there should be complete separation of traffic streams. It is on this last point that we in New Brunswick often fail.

While we are fortunate to have many kilometres of twinned highways, we also have several medium volume undivided Arterial Highways such as routes 7 and 11, to name two. And this is where we should consider Voltaire’s observation. We cannot afford to twin all our arterial roads, however we can afford to modify high-risk areas to minimize the chances of major collisions occurring.

If roads did not exist, and we were to ask an engineer to design a safe road for two-way traffic, how likely is it that they would deliberately place oncoming traffic,a mixture of family vehicles and large commercial trucks, heading towards each other at combined speeds of over 200kph separated only by a thin yellow line, encouraging, in places, faster traffic to move into the apposing lane, directly facing oncoming traffic, to pass slower vehicles? Unlikely! So now that we know better, with strong evidence to back up what is essentially good common sense, can we not introduce some simple low cost measures to improve safety?

 

We saw how the government acted quickly to enact “Ellen’s Law” legislating a minimum passing distance of one metre for cars passing cyclists. Should we not consider similar principles for oncoming traffic – perhaps widening the central yellow line to a one metre wide “painted barrier” on fast arterial roads? Kind of like a “double double” yellow line! The addition of central rumble strips to such a widened median, and the erection of central median barriers in high risk areas, with safe passing zones, are all much lower cost interventions than twinning every kilometer of our road network – the perfect solution that will never happen, yet the idea of which stops us implementing other solutions that could save lives. Let’s stop the perfect becoming the enemy of the good when it comes to road safety.

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Medical Student Clinical Pearl – Reversal of Anticoagulation in the Emergency Department

Reversal of Anticoagulation for Bleeding Complications in the ED


Tess Robart, Med 1

Dalhousie Medicine New Brunswick, Class of 2020

Reviewed by: Dr David Lewis and Liam Walsh (SJRH Pharmacy)


Clinical Question:

Emergency Departments frequently encounter patients on anticoagulant therapy. How are we currently managing anticoagulation reversal in our ED? How do we approach reversal, considering urgency in the face of major bleeding complications or prior to emergency surgery?

Background:

As result of the narrow therapeutic window of many anticoagulants, treatment presents a significant risk for life-threatening bleeds. Major bleeding involving the gastrointestinal, urinary tract, and soft tissue occurs in up to 6.5% of patients on anticoagulant therapy. The incidence of fatal bleeding is approximately 1% each year (1). Standard therapy for the control of coagulopathy related bleeding has traditionally required the use of available blood products, reversal of drug-induced anticoagulation, and recombinant activated factor VII (rFVIIa). The introduction of new direct oral anticoagulants (DOACs), dabigatran, apixaban and rivaroxaban presents the need for a new realm of antidotes and reversal agents.



Indications for Reversal:

Emergency physicians should consider reversal of anticoagulation for patients presenting with bleeding in the case of anticoagulant use, antiplatelet use, trauma, intracranial hemorrhage, stroke, and bleeding of the gastrointestinal tract, deep muscles, retro-ocular region, or joint spaces (2,3). The severity of each hemorrhage should be considered, reversing in cases of shock or if the patient requires blood transfusions because of excessive bleeding (2).

Patients should also undergo reversal of anticoagulation if urgent or emergent surgery is necessary (4).

For most medical conditions requiring anticoagulation, the target international normalized ratio (INR) is 2.0 to 3.0 (5). Notable exceptions to this rule are patients with mechanical heart valves, and antiphospholipid antibody syndrome. These patients require more intense anticoagulation, with target INR values between 2.5-3.5 (5).

The following laboratory assays should be considered, and repeated as clinically indicated (2):

  • PT/INR
  • aPTT
  • TT (thrombin time)
  • Basic Metabolic Panel
  • CBC

Initial assessment should address the following from a patient history (2):

  • How severe is the bleed, and where is it located?
  • Is the patient actively bleeding now?
  • Which agent is the patient receiving?
  • When was the last dose of anticoagulant administered?
  • Could the patient have taken an unintentional or intentional overdose of anticoagulant?
  • Does the patient have any history of renal or hepatic disease?
  • Is the patient taking other medications that would affect hemostasis?
  • Does the patient have any other comorbidities that would contribute to bleeding risk?

See this article for more details on the management of anticoagulation reversal in the face of major bleeding

It is important to note that not all coagulopathies will be anticoagulant drug induced. After all drug-induced causes have been ruled out, it is appropriate to follow previously established protocols (ie. transfusion protocol).


Table 1: Common Anticoagulants and Drug Reversal Considerations 


Table 2: Anticoagulant Reversal Agents (5)

 


Bottom Line: 

 

Anticoagulation leading to clinically significant bleeding is an issue commonly encountered in the emergency department. Therapies designed to combat and reverse anticoagulation are constantly changing in response to new anticoagulant medications. Emergency physicians must be well versed around anticoagulants commonly used, and recognize the antidotes used to treat their overuse in urgent and emergent situations.

 

 


References:

 

  1. Leissinger C.A., Blatt P.M., Hoots W.K., et al. Role of prothrombin complex concentrates in reversing warfarin anticoagulation: A review of the literature. Am J Hematol. 2008;83:137-43.
  2. Garcia D.A., Crowther M. (2017) Management of bleeding in patients receiving direct oral anticoagulants. Retrieved from https://www.uptodate.com/contents/management-of-bleeding-in-patients-receiving-direct-oral-anticoagulants?source=search_result&search=reversal%20of%20anticoagulation&selectedTitle=1~150
  3. UC Davis Health Centre. Reversal of Anticoagulants at UCDMC. Retrieved from Reversal of Anticoagulants at UCDMC – UC Davis Health
  4. Vigue B. Bench-to-bedside review: Optimising emergency reversal of vitamin K antagonists in severe haemorrhage–from theory to practice. Crit Care. 2009;13:209.
  5. Mathew, A. E, Kumar, A. (2010) Focus On: Reversal of Anticoagulation. American College of Emergency Physicians. Retrieved from https://www.acep.org/Clinical—Practice-Management/Focus-On–Reversal-of-Anticoagulation/
  6. Brooks J.C., Noncardiogenic pulmonary edema immediately following rapid protamine administration. Ann Pharmacotherap1999;33(9):927-30.
  7. National Advisory Committee on Blood and Blood Products. Recommendations for Use of Prothrombin Complex Concentrates in Canada. May 16, 2014. http://www.nacblood.ca/resources/guidelines/PCC-Recommendations-Final-2014-05-16.pdf
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RCP – Nar’ pump, mo’ problems

Nar’ pump, mo’ problems, a case on cardiogenic shock

Resident Clinical Pearl (RCP) – June 2017

Mandy Peach, R2 FMEM, Dalhousie University, Saint John, New Brunswick

Reviewed/Edited by Dr. David Lewis and Dr. Kavish Chandra

It’s 11 pm, you’re doing the overnight shift and EMS calls in to report a patient with an ETA of 3 minutes: “80 yo female, found on floor in apartment by husband after reportedly feeling unwell for 2 days. Decreased LOC but arousable and responding appropriately. BP 82/36, HR 120, RR 22, Afebrile, oxygen sat 86% on 6L nasal cannula.”

You hear the vitals, and many differentials run through your mind – PE, sepsis, hemorrhage, tamponade. Your main concerns are: this person needs more airway support and they are in shock, and when you think shock you think ‘fluids’.

EMS rolls in with your patient and she looks awful – pale, mottled extremities and drowsy. She is being re-assessed, RT is present to switch to a face mask, IV access is being established and you’re about to pound her with fluids when you are handed her ECG:

1https://lifeinthefastlane.com/ecg-library/basics/inferior-stemi/

This lady clearly is having an inferior STEMI – there is marked ST elevation in II, III and aVF with early Q wave formation.

 

Take home point #1: In any Inferior STEMI, you must suspect RV involvement

Look for ST elevation in V1 and depression in V2, or ST elevation in lead III > lead II. If these are present – get a 15 lead ECG.1

On closer look at our patient’s ECG there is ST elevation in V1-V2 and the elevation in lead III is indeed larger than lead II. You order the 15 lead.

2 https://lifeinthefastlane.com/ecg-library/right-ventricular-infarction/

Look for ST elevation in right sided leads V3-V6, but the money is on V4R – ST elevation in this lead has a sensitivity of 88%, specificity of 78% and diagnostic accuracy of 83% for RV infarction2. Our patient does have RV infarction seen by ST elevation in V4R.

 

Take home point #2: RV involvement is associated with increased risk of cardiogenic shock and death with a mortality of 50% within the first 48 hours3. If there is RV involvement, giving nitroglycerin for chest pain is CONTRAINDICATED

Due to a poorly functioning RV, patients are pre-load sensitive2. If you decrease the pre-load then they have even less to pump, further worsening the hypotension.

So we have diagnosed this lady with cardiogenic shock secondary to AMI (the most common cause of cardiac related shock) and we determined she has RV involvement. We know we can’t give her nitroglycerin. Let’s reassess her status – the basic ABC’s.

Airway & Breathing – the RT has since advanced her to a non-rebreather with a sat level in the high 80’s. You suggest trying Optiflow or BiPAP as a temporizing measure – this lady is going to need to be intubated.

 

Take home point #3: Positive pressure ventilation requires a stable, cooperative patient – which is often not the case in cardiogenic shock

Positive pressure can decrease pre-load and potentially worsen hypotension3. It is a temporizing measure only. The majority will require endotracheal intubation to maintain their saturation as their work of breathing is a large expenditure of energy.

You successfully complete a RSI and the saturation improves to 94-98%.

Circulation – Repeat BP is 82/36. You complete a cardiac point-of-care-ultrasound (PoCUS) and see poor contractility, but no pericardial effusion or large clots suggesting chordae or papillary rupture. IVC is > 50% collapsible.

 

Take home point #4: On PoCUS, heart failure caused by acute ischemia will show a large RV and small LV secondary to low filling pressures, which is best seen on the apical 4 chamber view3

Your patient continues to be hypotensive – you give a small 500 cc bolus; you don’t want to overload a poorly pumping heart with fluid it can’t handle. However you anticipate that this will not be enough to improve her BP, and as she continues to be hypotensive her myocardial ischemia worsens, which subsequently worsens her pump dysfunction in a vicious cycle. She needs pressure support.

 

Take home point #5: Cardiogenic shock requires vasopressor support

If systolic BP > 90: Start with dobutamine for inotropy. Double up on agents – likely will need to add a vasoconstrictor. Dopamine is usually the next to add.

If systolic BP < 90: Can still use dobutamine, but need to add norepinephrine for vasoconstriction. Dopamine alone will worsen BP as it is a vasodilator.

3Tintinalli’s Comprehensive Guide to Emergency Medicine.

You start dobutamine and dopamine peripherally with the intention of obtaining central venous assess once stabilized.

In the meantime, cardiac labs and portable CXR are pending, you treat this patient as any other STEMI in terms of dual anti-platelet and anti-coagulation loading.

 

Take home point #6: Do not give beta blockers

Do not give beta blockers in RV infarcts as high risk of bradycardia and AV block due to ischemia of the AV nodal artery3.

You consult cardiology to activate the cath lab.

 

Take home point #7: Early revascularization in ischemic related cardiogenic shock is key

Early revascularization has a long term mortality benefit, preferably if done within 6 hours4.  Catheterization or CABG is the preferred method over thrombolytic therapy.

You consult cardiology to activate the cath lab.

Back to our patient –

This lady did go on to the cath lab and had stenting of her RCA, however her infarct likely occurred > 48 hours before presentation. Unfortunately, despite aggressive vasopressor therapy and revascularization, she coded immediately after the procedure and resuscitation attempts were unsuccessful, emphasizing the poor prognosis associated with ischemia related cardiogenic shock.

 

Bottom line for cardiogenic shock: fluid bolus 500 cc 0.9% NaCl, vasopressor support and RSI. Early revascularization is key – catheterization is preferred. Despite these interventions, the diagnosis portends a poor prognosis.

 

References

  1. Inferior STEMI – Life in the Fast Lane https://lifeinthefastlane.com/ecg-library/basics/inferior-stemi/
  2. Right Ventricular Infarction – Life in the Fast Lane https://lifeinthefastlane.com/ecg-library/right-ventricular-infarction/
  3. Tintinalli, JE. (2016). Cardiogenic Shock (8th ed.) Tintinalli’s Emergency Medicine: A Comprehensive Study Guide (pages 349-352). New York: McGraw-Hill.
  4. Cardiogenic Shock – Literature Summary – Life in the Fast Lane https://lifeinthefastlane.com/ccc/cardiogenic-shock-literature-summaries/

 

This post was copyedited by Kavish Chandra @kavishpchandra

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Is CT-defined obstruction a predictor of urological intervention in emergency department patients presenting with renal colic?

Larger proximal ureteral stones with severe pain, rather than ureteral obstruction, are associated with urological intervention [excerpt]

…According to the latest Canadian Urological Association guidelines for management of ureteral stones, patients presenting with ureteral stones <5 mm could be managed conservatively, provided that they don’t have infectious symptoms, intolerable pain, or a threat to renal function.1 When urological intervention is contemplated, the decision-making process takes into account patient- related factors (intolerable pain, infectious complications, impending renal failure, coagulopathies and renal anomalies including solitary kidney); and stone-related factors (stone size, location, density, and skin-to-stone distance). However, signs of ureteral obstruction on computed tomography (CT) are not part of the guidelines.

In their study, Massaro et al performed a retrospective review of 195 patients presenting with ureteral stones at a tertiary Canadian centre [@SJRHEM] between 2011 and 2013.2 Forty-two per- cent of the patients presenting with ureteral stones underwent urological intervention, including cystoscopy with retrograde pyelography, placement of ureteric stent, shockwave lithotrip- sy, and/or ureteroscopic laser lithotripsy. A radiologist and a urologist independently reviewed all CT scans for prede ned criteria of ureteral obstruction (no obstruction, partial, or com- plete obstruction) based on degree of hydronephrosis, hydro- ureter, nephromegaly, and perinephric stranding. In addition, the authors examined other potential predictors for interven- tion, including patient demographics, stone size and location, amount of analgesics used, signs and symptoms of infection, serum creatinine, cumulative intravenous uid administered, and the prescription of medical expulsive therapy.

Not surprisingly, the authors found that stone size and location, in addition to cumulative opioid dose, were independent predictors for urological intervention. In fact, every mm increase in stone size increased the likelihood of intervention 2.2 times (odds ratio [OR] 2.17; 95%  [CI] 1.67‒2.85). The OR exceeded unity for stones larger than 4.5 mm, indicating higher likelihood of urological intervention for stones larger than 4.5 mm. Similarly, proximal stones were 4.7 times more likely to require intervention than distal stones (OR 0.21; 95% CI 0.09‒0.49). Finally, every 10 mg increase in morphine administered was associated with a 30% increase in the odds of intervention (OR 1.30; 95% CI 1.07‒1.58). However, degree of obstruction was not an independent predictor of intervention for ureteral stones (OR 1.757; 95% CI 0.899‒3.436). Finally, none of the variables predicted 30-day return to the emergency department (ED). This could be explained by the very low number of returns to the ED in both groups.

Despite its retrospective nature, this study con rms previ- ous studies that ureteral stone size (>4.5 mm), proximal loca- tion, and intractable pain requiring higher doses of opioids are associated with urological intervention. Furthermore, the degree of ureteral obstruction on CT scans did not pre- dict intervention. While CT scan ndings of hydronephrosis, hydroureter, nephromegaly, and perinephric stranding are helpful in diagnosing ureteral stones, they are not helpful in guiding the decision-making process for intervention.

Sero Andonian, MD, MSc, FRCSC, FACS; Associate Professor of Urology, McGill University, Montreal, QC, Canada

Cite as: Can Urol Assoc J 2017;11(3-4):93. http://dx.doi.org/10.5489/cuaj.4511

References

  1. Ordon M, Andonian S, Blew B, et al. CUA guideline: Management of ureteral calculi. Can Urol Assoc J 2015;9(11-12):E837-51. https://doi.org/10.5489/cuaj.3483
  2. Massaro PA, Kanji A, Atkinson P, et al. Is computed tomography-de ned obstruction a predictor of urological intervention in emergency department patients presenting with renal colic? Can Urol Assoc J 2017;11(3-4):88-92. http://dx.doi.org/10.5489/cuaj.4143

Read the @SJRHEM paper here…

Download (PDF, 268KB)

 

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