Archive | May, 2012

Antibiotics for MRSA abscesses? NO.

31 May

Schmitz et al. Randomized Controlled Trial of Trimethoprim-Sulfamethoxazole for Uncomplicated Skin Abscesses in Patients at Risk for Community-Associated Methicillin-Resistant Staphylococcus aureus Infection. Annals of Emergency Medicine, Vol 56, Sept 2010
Bactrim vs. placebo after incision and drainage.  
Multicenter, double-blind, RCT in 4 military ED’s
outcome: treatment failure after 7 days or reduction of new lesion formation in 30 days
                        Tx failure 7 days              New lesion within 30 days      
Placebo                     26%                                          28%
TMP/SMX                  17%                                           9%
Difference (95%CI)      9% (-2 to 21%)                         19% (4-34%)
As shown above, there was a significant difference of new lesions in 30 days.  only 45% were available at 30 days.  big confidence intervals.
Duong et al. Randomized, Controlled Trial of Antibiotics in the Management of Community-Acquired Skin Abscesses in the Pediatric Patient. Annals of Emergency Medicine, Vol 55, May 2010
Bactrim vs. placebo after incision and drainage
double-bind RCT in pediatric patients
outcome: treatment failure within 10 days (need for second incision, IV antibiotics, continued erythema, warmth, fluctuance at 10 day follow up).
              Failure to improve            10 day new lesions    90 day new lesions**
Placebo          5.3%                         26.4%                     28.8%
TMP/SMX       4.1%                         12.9%                     28.3%
** Note that only around 60% were effectively followed up at 90 days.
Conclusion: no difference in failure rates with or without antibiotics. 
Of note,  in treatment arm, only 46% of patients were compliant with antibiotics, taking at least half of the pills. 
Note that there are many other studies showing that antibiotic use does NOT eradicate MRSA.
Immunocompetent patients with MRSA abscesses can be treated with I & D alone. Not enough data to support consistent antibiotic use. 
Consider addition of antibiotics in diabetics, immunocompromised, or systemically ill. 
Submitted by S. Morris.

Reference(s): study 1, study 2, picture

passive preoxygenation – a radical concept

30 May

Next time you intubate someone
consider putting them on a nasal cannula at 15L per min under the NRB.  
this article advocates it as a form of “apneic oxygenation” which can prevent desaturation during intubation
Awake patients will not tolerate it at 15L/min, so you can start with 4-5 L and then increase to 15 after giving your induction and paralytic medications.
The point: Apneic oxygenation can extend the duration of safe apnea.
Note: High O2 could decrease the respiratory drive, but this is for people who you are committed to intubating already.  
I would love to hear your success stories with this new method!
Submitted by S. Morris.

steroids for pharyngitis + Centor criteria refresher

29 May

Meta-analysis of 9 RCT’s of adults and children using steroids for tonsillitis or pharyngitis 
did find more patients with resolution of pain with steroids at 24 or 48 hours.
All patients received antibiotics, which may have been confounding.
consider steroids (maybe prednisone 60mg x1 or 2 days) for adult patients with severe exudative sore throat in conjunction with antibiotics.
Of course, steroids have complications, so consider them when prescribing.
Hayward, G. (2009). Corticosteroids for pain relief in sore throat: systematic review and meta-analysis. British Medical Journal
a reminder of the Centor criteria (if you believe in them)
The 4 criteria are: 
  • fever
  • pharyngeal exudates
  • anterior cervical adenopathy
  • absence of a cough. 
The presence of a cough, hoarse voice, or conjunctivitis, suggests a viral etiology and is not considered a risk factor for group A beta-hemolytic strep. 
Centor criteria should not be used to predict GABS in children.

  • <2 points — No antibiotic or throat culture necessary.
    (Risk of strep infection <10%)
  • 2-3 points — Should receive a throat culture and treat with an antibiotic if culture is positive.
  • >3 points — Treat empirically with an antibiotic.
    (Risk of strep infection >50%)

Singer JI, Gebhart ME: Sore throat, in Marx JA, Hockberger RS, Walls RM (eds): Rosen’s Emergency Medicine Concepts and Clinical Practice, ed 6, St. Louis: Mosby, 2006: 274

Submitted by S. Morris.

Reference(s): hayward study; rosen’s chapter (listed above); picture

broaden your horizons (a.k.a. good luck diagnosing this one in the ED): EE

28 May

–patient with esophageal foreign body, mobilizing for GI swallow/scope
–foreign body resolved by the time GI swallow is done
–GI consult requests IgE… why?

Eosinophilic Esophagitis (EE) 

–mimics GERD and may result in narrowing or stricture of the esophagus.  

–differentiated from GERD by the amount of mucosal eosinophilia and lack of response to acid suppression.  

–In a cohort, 71% percent of patients with EE were male with a mean age of 10.5+/-5.4 years.  

–strong familial pattern 

sometimes first presents with lodged food boluses 2/2 stricture.  

Submitted by T. Boyd.

Reference(s): Noel et al. Eosinophilic Esophagitis Correspondence. NEJM. 351:940-941. Aug 2004. picture

broaden your horizons (a.k.a. good luck diagnosing this one in the ED): HLH

24 May

HLH (Hemophagocytic LymphoHistiocytosis)

–a condition where there is uncontrolled activation of the cellular immune system. 

–Diagnostic criteria include:

  • idiopathic fever
  • spleenomegaly
  • cytopenias
  • hypertriglyceridemia
  • hypofibrinogenemia
  • lymphadenopathy
  • rash
  • presence of hemophagaocytosis

–Varied skin manifestations:

  • erythroderma
  • generalized purpuric macules and papules
  • morbilliform eruptions. 

–You’re falling asleep right now reading this aren’t you?  

–Basically this is a rare but potentially fatal disease that no Emergency Physician will ever diagnose

–BUT if a patient comes in with this in their medical history, now you (sort of) know what to expect

Submitted by T. Boyd.

Reference(s): Favara BE. Hemophagocytic Lymphohistiocytosis: A He mophagocytic Syndrome. Smnr Diag Path. 1992. Schwartz et al. Lymphohistiocytosis. Emedicine.May 2011, picture

cervical artery dissection: quick review

23 May


first consult call to Neurologists (less commonly Vascular Surgeons)

–Vascular imaging is a must, but CTA is more sensitive than MRA.  

–To catch on MRI, specific sequences are required so check with your Neurologist/Radiologist to figure out which.  

Dissections that extend intracranially have a high incidence of forming SAH, especially when heparin is started, thus making heparin have higher mortality than anti-platelet drugs.  

Extracranial dissections are usually treated with antiplatelet drugs and anticoagulation

Submitted by T. Boyd.

Reference(s): Shea et al. Carotid and Vertebral Artery Dissections in the Emergency Department. Emergency Medicine Practice.14;4. April 2012; picture

possible open joint: how much do I infuse?

22 May

–patient arrives with wound around the knee
–want to inject saline in the joint capsule to see if it is open (if it leaks)
–how much saline do I put in there?

Keese et al. The Accuracy of the Saline Load Test in the Diagnosis of Traumatic Knee Arthrotomies. J. Orthop Trauma. 21;7. Aug 2007.

–study of 30 patients undergoing arthroscopy

–after arthroscopy hole was made each knee was injected with saline and measure how much it took until extravasation was seen.

–50ml of saline gave 46% sensitivity
–194ml of saline gave 95% sensitivity. 

–standard 50ml injection not great sensitivity in this small study
–200cc NS seemed to do the trick

Submitted by T. Boyd.

Reference(s): article, picture