The Negative or Inconclusive Ultrasound in Appendicitis – Can a CDR help?


The September edition of journal club featured two articles focused on the diagnosis of appendicitis.  These articles each highlight some critical EBM points, which is why I’m breaking them apart into separate posts. This post will only focus on the first article, which examined a potential clinical decision rule for the management of patients with inconclusive or negative ultrasonography in the setting of suspected appendicitis.



Acad Emerg Med. 2014 May;21(5):488-96. doi: 10.1111/acem.12374.

A simple clinical decision rule to rule out appendicitis in patients with nondiagnostic ultrasound results.

Leeuwenburgh MM1Stockmann HBBouma WHHoudijk APVerhagen MFVrouenraets BCobben LPBossuyt PMStoker JBoermeester MAOPTIMAP Study Group. 


  • Intent of the clinical decision rule (CDR) was to create a tool that could rule out appendicitis in patients with negative or inconclusive ultrasounds without additional imaging such as a CT or MRI and be safely discharged and seen the following day for reassessment.
  • Their aim was to identify low risk patients for appendicitis with negative or inconclusive ultrasound that they defined as <10%.
  • Carried out in the Netherlands at University and Teaching hospitals
Population and Inclusion Criteria
  • Development and Validation data were retrospectively extracted from 2 different imaging studies occurring at different times.
  • There were 199 patients in the development set and 120 patients in the validation set.
  • In both the development and validation set, subjects were selected from a diagnostic accuracy study and were patients with clinically suspected appendicitis that presented to the Emergency department who had negative or inconclusive ultrasound results.
  • All patients in both groups received additional imaging such as a CT scan. An expert panel that based its decision on all data attained including pathology and clinical course determined a final diagnosis of appendicitis.


  • 14 clinical variables associated with appendicitis were identified from the two diagnostic accuracy studies.
  • Development population: Univariate logistic regression methods were used to estimate odds of appendicitis based on each variable. Those with positive association were included in a multivariable logistic regression model; ultimately they came up with the most promising variables to build the CDR. CRP was added on to see if it would increase sensitivity.
  • 4 variables were identified to make a CDR (male, migration of pain to RLQ, vomiting and WBC >12), they applied this to the development and validation population retrospectively.
  • The 4 variables identified as most promising were male, migration of pain to RLQ, vomiting and WBC >12.
  • The addition of CRP>10 did not significantly improve the sensitivity of the rule.
  • The authors applied their 4 variable CDR to both the development and validation population set. In the development set they claim that use of the rule would reduce the probability of appendicitis from 26% (51/199 – these are the number that had +ve appy) to 12% (15/126 that were discharged ultimately had appendicitis)
  • In the validation set, applying the CDR reduced the probability of appendicitis from 20% (24/120 – total in group that had +ve appy) to 6% (4/72 – these were discharged home that ultimately had +ve appy).
  • They compare the NPV of the CDR as 94% (CI 87-98%), which was comparable to the NPV of CT and MRI (there was no statistical difference).
  • The authors conclude that their CDR significantly reduces the probability of appendicitis in negative and inconclusive u/s and those patients could be safely discharged home with next day evaluation.

Screen shot 2014-12-04 at 3.28.13 PM

Critical Appraisal/Group Discussion

There are multiple methodologic standards for interpreting a CDR.  The Annals of Emerg Med has a nice 2014 update on this here.  This would be a good paper to read or bookmark for residents.

The clinical scenario in which an emergency physician is presented with a young patient with clinically suspected appendicitis and an inconclusive ultrasound is common and one that could benefit from a well designed CDR to rule out disease in a moderate to high risk patient. Unfortunately, other than asking a relevant question, there are several limitations of this CDR that prevents it from being clinically useful.

First, the rule would have been more helpful if it resulted in a definitive course of action such as CT vs No CT or discharge only, rather than next day re-evaluation for all. Its design and methodological standards were also not ideal. Data for both the development and validation were retrospectively taken from two separate diagnostic accuracy studies that a priori were not designed to create a CDR. Patients were selected as a convenience sample introducing sampling and spectrum bias and there was no mention of blinding. Resident and staff radiologists performed ultrasounds, which is not the standard here in Canada. This may also explain the high rate of positive appendicitis in negative ultrasounds as the skill level of the ultrasonographers varied immensely.

It was also puzzling that the authors included negative ultrasounds in their study, as most physicians with a negative ultrasound would typically send the patient home with clear discharge instructions. In addition, the radiologists were aware of the fact that they were involved in a diagnostic accuracy study that likely introduced a performance bias and may have influenced the high inconclusive ultrasound rate (22 and 47%). In addition to the aforementioned, external validity was also limited by the CDR performance difference in the development and validation set (12% vs 6% miss rate) and by a high prevalence of appendicitis (52-60%). There were a few experts in pediatric appendicitis in attendance and our local data was quite different – we had a much lower prevalence of incompletely visualized appendices.

Ultimately there was consensus that a ‘miss rate’ of 12% was too high for both pediatric and adult populations. A miss rate of 3-5% would be more reasonable. In general when most staff are presented with a negative ultrasound, if there is a re-assuring re-examination of the patient they will discharge them with very clear instructions of when to return to medical attention. With respect to an inconclusive ultrasound, where there is a lot more diagnostic uncertainty, most staff will proceed to a CT scan if clinically concerned in the adult population. Our pediatric emergency colleagues typically get their patients admitted for serial examinations from general surgery.

An inconclusive ultrasound in the context of clinically suspected appendicitis remains a clinical presentation that would benefit from a CDR that is both methodologically rigorous in derivation and leads to a defined clinical action.

Look for more on appendicitis in the coming weeks.  We review a meta-analysis of the Alvarado Score and Pediatric Appendicitis Score, and focus on measures of heterogeneity within a meta-analysis.

Thanks to Natasha Wright (PGY-2) for contributing and Shawn Dowling (FRCPC) for reviewing this summary.




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The Spectrum App : A Must Have for Calgary Physicians and Residents

Screen shot 2014-11-26 at 8.45.38 PM

Disclaimer: I am not paid for the following overwhelmingly complimentary review of an app.

If you are a doctor or nurse working in Calgary, you should immediately click this link on your iPhone and download the free Spectrum App.

Okay, I guess you may want to know what this is.  The Spectrum App is a fantastic program containing local Calgary antibiograms describing the sensitivities of community-acquired, hospital-acquired and ICU-acquired bacterial infections.  There is actually even more than that, but these alone are worth the 10 seconds required to download this.

In addition to the antibiograms, there are details for antibiotic doses and cost, a dosing calculator for renal adjustment, as well as criteria for diagnoses (eg. Cholecystitis, Febrile neutropenia, SBP) and much more.  I haven’t even fully explored this App, but wanted to get the word out now.  Soon I will realize its full power!

Thanks to one of the EM residents, Kathryn Crowder, for telling me about this awesome app.





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Should we use tetracaine for corneal abrasions? Calgary EM Journal Club


Hi all,

This month’s Calgary EM Journal Club had a fantastic turnout with almost 40 attendees, 25% of which were staff EM docs.  It also marked the first time we saw a heated, debate style showdown at the end from residents advocating for and against the use of topical tetracaine in treatment of corneal abrasions.  Two articles were reviewed, one by Ball et al. from CJEM 2010, and another by Waldman et al. from Academic Emerg Med 2014.  For previous journal club reviews, check out the journal club page.

The traditional dogma prohibiting use of topical tetracaine for treatment of corneal abrasions has been challenged in the past few years, gaining steam with the recent publication of Waldman’s article in April, 2014.  Textbooks tell us that topical tetracaine is toxic to corneas, and will result in corneal thinning, ulcers, keratitis and other ocular complications.  However, this is based primarily on animal, case report and case series data.  Fortunately, my friends Salim Rezzaie of and Ken Milne of have posted about this dogma already, and I encourage you to check out their reviews, as well as Ken’s podcast over at TheSGEM.

The complete critical appraisal of both articles is available if you scroll down, however we’ll get to the bottom line right away as it is slightly different than what some others in the FOAM world are saying.

Clinical Bottom Line:

Given the current evidence, few physicians would universally provide topical tetracaine for the treatment of corneal abrasions, although some would consider it on a case-by-case basis until new data is available.

Prior to the evening’s discussion 9/38 journal club attendees would consider short-term topical anesthetics for corneal abrasions with 16/38 attendees considering this after discussion.


As the main concern of the therapy is with respect to safety with potentially vision-threatening complications, a (0-6.1%) confidence interval was thought to be not yet ready to conclusively prove safety.  In order to prove safety, we are probably going to need somewhere in the realm of  1000 patients with corneal abrasions, and I think we have just over 100 right now in the EM literature. The photorefractive keratectomy (PRK) literature from the ophtho world can’t be grouped with the ED corneal abrasions because these are sterile, surgical incisions.

Furthermore, polling the ophthalmology consultant group, there is essentially no support of this treatment strategy, citing local anesthetic’s inhibition of corneal healing.

This will be the most important determinant of tetracaine use in your local center.  Will your ophtho colleagues support you? Will they support you in the case of a complication?

Below are full summaries of each article.


Article #1

Acad Emerg Med. 2014 Apr;21(4):374-82. doi: 10.1111/acem.12346.

Topical tetracaine used for 24 hours is safe and rated highly effective by patients for the treatment of pain caused by corneal abrasions: a double-blind, randomized clinical trial.

Waldman N1Densie IK, Herbison P. 


  • Double blinded randomized controlled trial from 2011 to 2012.
  • Study population: 116 patients with simple acute corneal abrasions presenting to a tertiary care Emergency Department in New Zealand
    • This size was a convenience sample with a post hoc 95% confidence interval for 0 complications of (0-6.1%)


  • Simple, uncomplicated corneal abrasion from mechanical trauma, UV keratitis or foreign body.


  • Patient characteristics: age < 18, previous eye surgery, cataracts, deaf, unable to give informed consent, were unable to follow-up in 48 hours, and contact lens users.
  • Presentation > 36 hours
  • Ocular infection, herpes keratitis, concurrent injury requiring urgent ophthalmologic evaluation*
  • Bilateral Abrasion
  • Grossly contaminated foreign body.

*Although what mandates urgent ophthalmologic evaluation was not explicitly defined, suggested examples include complicated corneal abrasions, change in visual acuity and large corneal abrasion.


  • 1:1 sealed envelope randomization to either intervention or control:
  • Control envelope: 3x 1000mg acetaminophen tablets every 6 hours, 1% preservative chloramphenicol + 5cc saline eye drop placebo.
  • Intervention envelope: 3x 1000mg acetaminophen tablets every 6 hours, 1% preservative chloramphenicol + 5cc preservative-free 1%(undiluted) tetracaine.


Outcome measure(s):


Complication rate, as defined by any of: delayed healing, enlarged abrasion, corneal ulceration, toxic keratitis, surface keratopathy, corneal stromal infiltrates, infectious keratitis, uveitis and corneal infiltrates. This was assessed by combination routine 48 hour follow-up ED assessment/telephone interviews, and discretionary ophthalmologic follow-up.


Pain scores on a 100mm visual analog scale.

Patient ratings of treatment effectiveness on a numeric rating scale during telephone follow-up.



  • There was no statistically significant difference in complication rates between treatment and control groups. No patients had any significant objective complications requiring changes in management.
  • These complications at 48 hours included persistent reuptake (23.9% v 21.3%) and persistent symptoms (21.7% v 21.35.) Of these patients, 5 required reassessment by ophthalmology but none required any additional treatment.


  • There was no clinically significant difference in pain scores at any time during the 48 hour treatment period, however there was a significantly higher mean followup NRS of tetracaine’s effectiveness. (7.7 v 3.8; p<0.0005.)


  • Topical 1% tetracaine is a safe and effective symptomatic treatment for acute, uncomplicated corneal abrasions.


Article #2

CJEM. 2010 Sep;12(5):389-96.

Dilute proparacaine for the management of acute corneal injuries in the emergency department.

Ball IM1Seabrook JDesai N, Allen L, Anderson S.



  • Double blinded randomized placebo-controlled trial.
  • 2 tertiary level care EDs in London, Ont.
  • 33 patients
  • Powered to detect with 80% power a 2cm difference in a 10cm visual analog pain scale.


  • Adults with corneal injuries.


  • Inability to consent
  • Allergy to medication
  • Inability to followup
  • Previous eye injury or pathology


  • 1:1 randomization to topical fluoroquinolone, pain log, acetaminophen+codeine, and:
  • Intervention: topical proparacaine to 0.05%
  • Control: topical saline drops matched by colour and smell.


Outcome measure(s):


Difference in pain immediately before and 5 minutes after drop administration. Pain recorded on 2 separate 10cm visual analog scales. Pain log handed in at 5 days.


Self-reported patient satisfaction on a 10cm visual analog scale.

Complications as assessed by a single ophthalmologist at 1,3, and 5 days, defined as:

  • Delayed wound by fluorescein
  • Increased corneal thickness
  • Corneal opacification
  • New corneal epithelial defects
  • Any other ocular pathology that could be related to the injury or medication



  • There was a significant decrease in pain in the intervention group. Mean reduction was 3.9 in the intervention group, and 0.6 in the control (p=0.007)


  • The intervention group had an improvement in patient satisfaction scores of 8 compared to 2.6 (p=0.027).
  • There were no complications in either of the 2 groups.


  • Topical diluted 0.05% proparacaine reduces pain due to corneal injuries and likely does not cause complications.


Thanks to Geoff Lampard (PGY4), Michael Szava-Kovats (PGY4) and Shawn Dowling for this month’s journal club. For more U of C Journal Club reviews, click here

Chris Bond


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Hi all,

Screen shot 2014-08-11 at 2.28.43 PM

I’m excited to report that I’ve joined the group over at (Rezaie’s Evidence Based Evaluation of Literature in Emergency Medicine) and my first post on the use of Colchicine for treatment of pericarditis is now up.

For those of you who don’t follow REBEL:EM, what are you waiting for?  With Salim Rezaie (@srrezaie), Anand Swaminathan (@EMSwami), Matt Astin (@mastinmd) and multiple other guest contributors, this site is cranking out practical, evidence based content every few days.

I’ll still be posting/cross-posting here, but also have a few other projects that I’m working on.


Chris (@socmobem)

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Novel therapies for Anterior Epistaxis (Calgary EM Journal Club)


Epistaxis can be managed in many ways, from a simple squeeze of the nose to stuffing it with a tampon, and everything in between.  Today we’ll look at two novel methods of managing anterior epistaxis, one of which has become my go to for the moderate, non-anticoagulated bleeder.  Both of these techniques obviate the need for packing and are thus very popular among both patients and physicians.  These articles were reviewed at the University of Calgary EM Journal Club, May 2014.

For a review of epistaxis and a solid general approach, here are a few options:

1)The Skeptics Guide to Emergency Medicine ( Episode #53 “Sunday, Bloody Sunday” - Ken reviews the basics and one of the articles we’ll discuss here today.

2)For a very thorough approach, check out Schlosser’s NEJM review of epistaxis from 2009. (Subscription required)

Option #1 – Tranexamic Acid

The first new option for epistaxis is topical application of the IV form of tranexamic acid.  Incredibly easy to do, just take an ampoule of TXA (1 gram/10 mL) and soak 15 cm of cotton pledget/gauze with 500 mg (5 mL) of the TXA solution.  Stuff it up the nostril, get them to pinch the nose for 15 minutes and come back.  The bonus is that you have 500 mg for the other nostril in the same vial, so feel free to do both.

This technique was far superior to traditional packing in terms of ED length of stay, patient/physician satisfaction, and had no increased rate of re-bleed at 7 days.  I have personally found this technique tremendously successful in my limited use thus far.  1 of 4 patients failed, but their INR would have precluded them from the study anyway.

NB. Patients with an INR > 1.5 were excluded from this study. See BEEM Commentary section.

Full journal article critical appraisal is below.

Option #2 – Floseal Hemostatic Matrix

The second new option is actually not so new.  It comes from a 2005 paper in Laryngoscope and compares the use of Floseal gel matrix to traditional packing.  Floseal is a product similar to Gelfoam, Surgicel, etc. used for hemostasis, except it does not require platelet activation like the others.  This is theoretically fantastic as many of our epistaxis patients are on ASA/Clopidogrel or other anti-platelet agents.  Notably, this study included patients with INRs up to 4.5 and had fewer exclusion criteria than the TXA study.

This was a small, 70 patient study with industry sponsorship (BTW, I get paid nothing by anyone!) that showed improved patient/physician satisfaction, reduced head and neck surgery (HNS) consultation rates and decreased re-bleed rates in the Floseal group.

My main issue with the Floseal study is that I don’t have Floseal!! I’m not sure if anyone else has experience with this product, would love to hear your comments if you do.  It looks to be about $165/application, which although more than a nasal tampon, probably pays for itself with reduced re-visits and HNS consults.  However, I could just use TXA for many of these patients and it costs pennies.

Full article critical appraisal is below.

Article #1

A new and rapid method for epistaxis treatment using injectable form of tranexamic acid topically: a randomized controlled trial

Clinical Question:Is topical tranexamic acid (TXA) superior to traditional nasal packing for the treatment of anterior epistaxis?

Reference:American Journal of Emergency Medicine 31 (2013) 1389–1392

PubMed ID:23911102

Population:   Adult ED patients (n=216)

Intervention: 15 cm cotton pledget soaked in injectable TXA (500 mg in 5 mL) inserted into the bleeding nostril.

Comparison: Cotton pledget soaked in epiephrine (1:100000) + lidocaine (2%) for 10 minutes followed by packing with cotton pledgets coated in tetracycline.

Outcome:     Cessation of epistaxis within 10 minutes, rebleeding at 24 hours and 7 days, length of stay (LOS) and patient satisfaction.
Authors’ Conclusions: “Treating anterior epistaxis with the topical use of injectable form of tranexamic acid is better than usual nasal packing”.

Quality Checklist:

1. The study population included or focused on those in the ED.  Yes.

2. The patients were adequately randomized. Yes.

3. The randomization process was concealed.  Yes.

4. The patients were analyzed in the groups to which they were randomized. Yes.

5. The study patients were recruited consecutively (i.e. no selection bias).  Unsure.

6. The patients in both groups were similar with respect to prognostic factors.  No.

7. All participants (patients, clinicians, outcome assessors) were unaware of group allocation.  No.

8. All groups were treated equally except for the intervention. Yes.

9. Follow-up was complete (i.e. at least 80% for both groups). Yes.

10. All patient-important outcomes were considered. Yes.

11. The treatment effect was large enough and precise enough to be clinically significant.  Yes.  

Key Results:

Outcome TXA (%) Anterior nasal packing Odds Ratio (95% CI) p-value
Bleeding stopped < 10 min 71 31.2 2.28 (1.68-3.09) <0.001
Discharge <2 hours 95.3 6.4 14.8 (7.2-30.4) <0.001
Complications 4.7 11 0.42 (0.15-1.16) 0.128
Re-bleed at 24 hrs 4.7 12.8 0.36 (0.14-0.98) 0.034
Re-bleed at 1 week 2.8 11 0.26 (0.07-0.88) 0.018
Patient satisfaction 85 44 <0.001


BEEM Commentary:

The patients in the TXA group had a much higher rate of previous epistaxis (58.1% vs. 13.6%) compared with the packing group. This could alter the authors conclusions. Physicians were not blinded to treatment group which is a potential source of bias. Finally, many groups were excluded in this study, including, INR >1.5, visible bleeding vessel, major trauma, pre-existing coagulopathy and posterior bleeds.

Comments on author’s conclusion compared to BEEM conclusion:

This study did show positive outcomes with using tranexamic acid for anterior epistaxis, although many patient groups were excluded from the study.

The Bottom Line:

TXA seems to be a good alternative to nasal packing for earlier patient discharge and improved patient satisfaction.

Clinical Application:

Consider using a TXA soaked cotton pledget for your next anterior epistaxis patient.

What do I tell my patients?

We have several options for treating your nosebleed. One of them is to soak some cotton with a medication called tranexamic acid and leave it in your nose for 10-15 minutes. If it works, it will allow you to go home sooner and without nasal packing that has to be removed in a few days. 

Reviewers: Chris Bond and Ken Milne


Article #2 

Prospective, Randomized, Controlled Clinical Trial of a Novel Matrix Hemostatic Sealant in Patients with Acute Anterior Epistaxis

Clinical Question:How does Floseal Matrix Hemostatic Sealant (Floseal) compare to nasal packing for the treatment of anterior epistaxis?

Reference:Laryngoscope. 2005 May;115(5):899-902.

PubMed ID:15867662

Population:   Adults (>18) with acute anterior epistaxis (n=70)

Intervention: Floseal Matrix Hemostatic Sealant

Comparison: Traditional nasal packing (eg. Merocel, Vaseline gauze, Rhinorocket, etc.)

Outcome:      Patient level of comfort and satisfaction, MD assessed effectiveness, ease of use and satisfaction, HNS (head and neck suregery) surgery consult rate, rebleed rate and crossover into other group.

Authors’ Conclusions: Floseal is more effective than nasal packing in treating patients with acute anterior epistaxis.

Quality Checklist:

1. The study population included or focused on those in the ED.  Yes.

2. The patients were adequately randomized.  Yes.

3. The randomization process was concealed. Yes.

4. The patients were analyzed in the groups to which they were randomized. Yes.

5. The study patients were recruited consecutively (i.e. no selection bias). Unsure.                                    

6. The patients in both groups were similar with respect to prognostic factors.  Yes. 

7. All participants (patients, clinicians, outcome assessors) were unaware of group allocation.  No.

8. All groups were treated equally except for the intervention.  No.

9. Follow-up was complete (i.e. at least 80% for both groups).  Unsure.

10. All patient-important outcomes were considered.   Yes.

11. The treatment effect was large enough and precise enough to be clinically significant.   Yes.

Key Results:

Reduced rate of HNS consult in Floseal group (8.6% vs. 31%, p<0.05), reduced rebleed rate within 7 days (14% vs 40%, p<0.05), reduced rebleed at follow-up visit (0% vs. 63%, p<0.001) and increased crossover in the packing group (23% vs. 3%, p<0.05).  Patient comfort and satisfaction was much better in the Floseal group, as was MD assessed effectiveness, ease of use and satisfaction (all p<0.001).

BEEM Commentary:

While the results are compelling, this study does have several limitations.  This was an industry funded,  non-blinded study and thus the MD and patient questionnaires are at significant risk for bias.   Furthermore, this was a small study (70 patients) and the primary outcome was not specified. We also do not know if patients were recruited consecutively, and are unsure of which group the crossover patients (23% in the packing arm) were analyzed in.  Other treatment (such as hypertension) was left to the discretion of the treating physician. Floseal is significantly more expensive than traditional packing methods ($165/application), however, this cost is likely offset by the decreased need for HNS consultation and lower rebleed rate.

Comments on author’s conclusion compared to BEEM conclusion:

Although the study does suffer from several limitations, it would be difficult to blind patients to gel matrix vs. packing, and Floseal for anterior epistaxis seems to be a reasonable option.

The Bottom Line:

Floseal is a potentially useful option for the management of anterior epistaxis.

Clinical Application:

Floseal offers another alternative in the management of anterior epistaxis.

What do I tell my patients?

We have several options for managing your nosebleed.  One of them is to insert a gel like substance into the nostril to stop the bleeding.  If it works, it will be more comfortable than inserting nasal packing and won’t increase your chance of rebleeding. 

Reviewers:Chris Bond


Questions? Experience with Floseal, Surgicel, etc. for epistaxis?  Please comment below.






Schlosser RJ.  Clinical Practice: Epistaxis. N Engl J Med. 2009 Feb 19;360(8):784-9. doi: 10.1056/NEJMcp0807078.

Zahed RMoharamzadeh PAlizadeharasi SGhasemi ASaeedi MAmerican Journal of Emergency Medicine 31 (2013) 1389–1392

Mathiasen RA, Cruz RM. Laryngoscope. 2005 May;115(5):899-902.

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A Matter of Convenience: Improper Drug Dosing in the ED

Sergey Motov (@smotovmd) sparked an interesting Twitter debate last month with his poster that looked at ketorolac (Toradol) dosing in the ED.


I have previously written about ketorolac in NSAIDs parts one, two and three.

Elisha Targonsky (@ETube) commented that the equi-analgesic and less GI toxic 10 mg ketorolac dose is standard in his EDWhaaaatttt?


But how? I’ve worked in several EDs and have never seen the 10 or 15 mg dose of ketorolac used regularly.  How could it be that 10 mg is used regularly in this ED?  Simple.


Which prompted Sergey and I to say

So simple, yet so brilliant!


This got me thinking, if we change the packaging, we can change the practice!


In most EDs, including mine, the ketorolac vial is 30 mg/mL in a 1 mL vial.  This makes it fairly obvious that convenience is at least part of the reason 30 mg remains standard dosing for ketorolac. If everyone only had 10 mg vial, I’m sure it would become the standard dose in no time.

There are many medications that are commonly dosed incorrectly because the convenience of not opening a second vial or hanging a second bag, etc.

A few examples:


The first dose of vancomycin is often dosed at 1 gram when it should be 15-20 mg/kg or 25-30 mg/kg (up to a maximum dose of 2 grams) in septic shock or meningitis.   Bryan Hayes (@pharmertoxguy) reviews the literature on this subject here at Academic Life in Emergency Medicine.


Various doses of rocuronium will result in paralysis and optimize intubating conditions.  However, for rapid sequence intubation (RSI), the 1.2 mg/kg dose results in more rapid paralysis (Magorian, Flannery, Miller, Anesthesiology 1993), and also provides a greater safe apnea time for intubation prior to hypoxia (Taha SK et al. Anesthesia 2010 and Tang et al. Acta Anaesthesiology Scandinavia 2011).

Unfortunately rocuronium comes in a 50 mg, 1 mL vial.   This frequently leads to inadequate dosing because a 70-80 kg (or more) patient will only be given 50 mg in order to save opening the extra vial.  When dealing with hypotensive ED patients it may be even more important to use the 1.2 mg/kg dose of roc, given potential decreased drug effects due to hypoperfusion and prolonged time to circulation.

These are just three common examples I can think of, but I’m sure there are many more.  What drugs do you find are dosed improperly on a regular basis?  I look forward to your comments.





Anesthesiology. 1993 Nov;79(5):913-8.

Comparison of rocuronium, succinylcholine, and vecuronium for rapid-sequence induction of anesthesia in adultpatients.

Magorian T1Flannery KBMiller RD.


Anaesthesia. 2010 Apr;65(4):358-61. doi: 10.1111/j.1365-2044.2010.06243.x.

Effect of suxamethonium vs rocuronium on onset of oxygen desaturation during apnoea following rapid sequence induction.

Taha SK1, El-Khatib MF, Baraka AS, Haidar YA, Abdallah FW, Zbeidy RA, Siddik-Sayyid SM.


Acta Anaesthesiol Scand. 2011 Feb;55(2):203-8. doi: 10.1111/j.1399-6576.2010.02365.x.

Desaturation following rapid sequence induction using succinylcholine vs. rocuronium in overweight patients.

Tang L1, Li S, Huang S, Ma H, Wang Z.


Vancomycin dosing in the ER from Bryan Hayes @pharmertoxguy

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