“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 effect 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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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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