Sunday, December 27, 2015

Monday, November 2, 2015

A Comfortable Miss Rate? Who Needs an LP after CT?



Clinical Scenario: A middle-aged man with a history of hypertension, diabetes mellitus, obesity, and peripheral vascular disease presents to the ED after an episode of syncope about 30 minutes ago. He is now completely alert and oriented and complains of a severe headache. Your initial workup, including basic labs, EKG, troponin, and non-contrast head CT, is unremarkable, and you prepare to admit him for observation and an inpatient syncope workup. The hospitalist service calls back to request a lumbar puncture to rule out subarachnoid hemorrhage before the patient comes up to the floor. Should you get the LP?

Clinical Question: In patients with a non-diagnostic non-contrast head CT, is a lumbar puncture necessary to completely rule out subarachnoid hemorrhage?

Literature Review:  
In medical school, we all learn that head CT alone is not sufficient to rule out a subarachnoid hemorrhage (SAH) in a patient with a sufficiently suspicious history- you also need a lumbar puncture (LP), to evaluate for blood in the CSF or xanthochromia. On standardized tests, no patient with risk factors and a sudden-onset headache gets to escape the LP needle… but is this the right way to go about things in clinical practice?

Most experts and clinical guidelines continue to recommend LP after negative head CT in patients at high risk of SAH. In the 2012 guidelines for the diagnosis and treatment of SAH, the American Heart Association and American Stroke Association recommend that “head CT, if nondiagnostic, should be followed by lumbar puncture (Class I, Level of Evidence: B).”[1] This recommendation is based mainly on older studies demonstrating decline in the sensitivity of head CT over the course of days.

However, newer studies using modern multi-detector CT scanners may have identified a subclass of patients in whom an LP is not required to rule out SAH.  Perry and colleagues performed a multi-center prospective cohort study to assess the sensitivity of modern third-generation CT in ED patients being evaluated for SAH [2]. Patients presenting to 11 Canadian tertiary care referral centers between November 2000 and December 2009 with suspected SAH were prospectively enrolled. Alert (GCS=15) patients over 15 years of age presenting with non-traumatic acute headache or syncope associated with headache were included in the study. Exclusion criteria included the presence of focal neurologic deficits or papilledema, known history of CNS abnormality (such as neoplasm, aneurysm, or shunt), recurrent headaches, and transfer from another center with an established diagnosis of SAH. The gold standard for diagnosis of SAH was subarachnoid blood on non-contrast head CT, any visually identified xanthochromia on CSF analysis, or RBCs in the final tube of CSF collected AND aneurysm identified on CT angiography. A major weakness of the study was that not all patients enrolled had both a head CT and a lumbar puncture. In an attempt to correct for this weakness, all patients who did not have a definitive diagnosis based on neuroimaging OR a negative LP were followed for six months to ascertain their outcomes. By the conclusion of the study, 3,132 patients had been enrolled; of these, 240 had confirmed SAH. For all comers, the sensitivity of head CT was 92.9% (95% CI 89.0%-95.5%) and the negative predictive value was 99.4% (99.1%-99.6%). However, for patients who were scanned within six hours of headache onset, the sensitivity of head CT was 100% (97.0%-100%), and the negative predictive value was 100% (99.5%-100%). Likelihood ratios were not reported; however, using data available in the paper, they were calculated as a negative likelihood ratio of 0.07 (0.05-0.11) for all comers, and an impressive 0.00 (0.00-0.03) for patients scanned within six hours of headache onset. 


The results of this study were later replicated by Backes and colleagues [4]. In this retrospective single-center cohort study, patients presenting to the ED with a history suspicious for SAH between 2005 and 2012 were enrolled. Patients with clinical suspicion of a non-traumatic SAH and a normal level of consciousness (GCS=15) were included. Exclusion criteria included unknown time of symptom onset, focal neurologic deficits on presentation, referral from another hospital with a confirmed diagnosis of SAH, and LP in the month before presentation. At the study site, all patients with suspicion of SAH undergo non-contrast head CT, and all patients with a nondiagnostic head CT undergo LP with CSF analysis at least 12 hours after symptom onset; patient databases were reviewed to generate a study population of 250 patients who met criteria.  In all comers, head CT had a sensitivity of 95.4% (89.5%-98.5%), negative predictive value of 96.6% (92.2%-98.9%), and negative likelihood ratio of 0.05 (0.02-1.11). In patients scanned within 6 hours of symptom onset, sensitivity was 98.5% (92.1%-100%), negative predictive value 98.6% (92.3%-100%), and negative likelihood ratio 0.02 (0.00-0.10). In fact, only one patient with a non-diagnostic head CT had any findings on LP; this was a patient with atypical symptoms who was subsequently found to have a bleeding cervical AVM. The authors conclude that in patients with typical symptoms who present and are scanned within six hours of headache onset, there is no need for an LP after non-diagnostic head CT to rule out SAH. Weaknesses of this study included its small sample size and retrospective design.

There are, of course, many patients who still warrant an LP after non-diagnostic head CT. Patients with an altered level of consciousness or focal neurologic deficits were excluded from the above studies and require more intensive diagnostics. These findings are not generalizable to patients with an unknown time of symptom onset, significant anemia, pediatric patients, or patients who present to community centers that lack 24/7 coverage by experienced neuroradiologists—note that both studies were performed at academic tertiary referral centers. Some experts also raise the possibility that stopping the ED workup after a non-diagnostic head CT might miss minor “sentinel” bleeds [5], citing a 1987 study showing that head CT missed “sentinel” bleeds in 55% of patients, while LP, when performed, was positive in all patients later diagnosed with SAH[6]. However, this study was performed in 1987, prior to the introduction of modern third-generation CT scanners, and any attempt at replication would likely show improved testing characteristics for CT alone.

Clinical Takehome : In alert adult patients with a suspected non-traumatic SAH and no focal neurologic deficits who are scanned within 6 hours of symptom onset, a non-diagnostic head CT is sufficient to exclude SAH in patients with a low to moderate pre-test probability of SAH.

Submitted by Kevin Baumgartner, PGY-1

Faculty Reviewed by Brian Cohn

Additional related #FOAMed resources:
LP for subarachnoid hemorrhage: The 700 Club
SGEM #134: on what British docs say about LP    

References
1. Connolly et al. “Guidelines for the management of aneurysmal subarachnoid hemorrhage: a guide for healthcare professionals from the American Heart Association/American Stroke Association.” Stroke 2012 Jun; 43(6): 1711-1737 
2. Perry et al. “Sensitivity of computed tomography performed within six hours of onset of headache for diagnosis of subarachnoid haemorrhage: prospective cohort study.” BMJ 2011; 343 
3. Alan Schwartz. “Diagnostic Test Calculator.” Department of Medical Education, University of Illinois at Chicago. [http://araw.mede.uic.edu/cgi-bin/testcalc.pl] 
4. Backes et al. “Time-dependent characteristics of head computed tomography in patients suspected of nontraumatic subarachnoid hemorrhage.” Stroke 2012 Aug; 43(8):2115-9 
5. Singer RJ, Ogilvy CS, Rodorf G. “Clinical manifestations and diagnosis of aneurysmal subarachnoid hemorrhage.” UpToDate. Literature review complete through September 2015; article last updated September 2013. 
6. Leblanc R. “The minor leak preceding subarachnoid hemorrhage.” J Neurosurg 1987; 66(1):35

Thursday, October 29, 2015

@WUSTL_EM #EMConf: #FOAMed Supplement No. 18 & 19

Conference October  21st [LJ]
1. Interesting Case Conference
Sometimes its important to know the atypical presentations of common diseases.  This week we discussed Kawasaki Shock syndrome.  emdocs discusses the reasons for delayed diagnosis in Kawaski disease. f you are having trouble remember all the diagnostic criteria, check out the ALiEM  card for Kawasaki's disease.

2. Abscess/Cellulitis and Antibiotics
- Dr. Willman gave a great presentation discussing the benefit of antibiotics in patients with abscess/cellulitis.
- EP Monthly promotes skipping the antibiotics unless systemic illness or severe immunosuppression is present.
- FOAMcast discusses the ISDA guidelines suggesting that Bactrim is probably sufficient as a single agent for MRSA and Strep Coverage.
- On a related topic, the SGEM discusses Clinda vs Bactrim for SSTI

3. EMS and the changing the healthcare landscape. 
Dr. Brent Myers discussed the coming tide of payment reform and its effect on EMS.  JEMS discusses EMS and bundled payments.

Conference October 27th [MD]
1. ECGs in PE
- We covered Amal Mattu's episode of ECG findings of PE.   Take home:  Inferior + Anteroseptal T waves inversions > think PE!
- Everyday EBM EKG Challenge No. 5 reviews an interesting case of  ST elevation in PE.
- Dr. Smith's ECG blog covers the ECG findings in PE

2. #RightCare in Emergency Medicine
- To Read More about the Lown Institute, check out their webpage or focus specifically on Right Care Action week here.
- If you did not get a chance to read the Wired article about David Newman, do so now and make sure to check out the NNT.com
- To read more about the silent epidemic of preference misdiagnosis check out these two blog posts at the BMJ: 1 and 2.
- Shared Decision Making is one technique to avoid Preference Misdiagnosis.  Read about Emergency Physicians Perceptions of Shared Decision Making in this article in Academic Emergency Medicine.
- Check out our own Hippocratic Medicine series about examples of the harms of overtesting or overuse, and stay tuned for an upcoming post on Lessons from #RightCare Week at the Barnes Jewish ED.

Enjoy,
Louis Jamtgaard (@Lgaard)
Maia Dorsett (@maiadorsett)

Wednesday, October 21, 2015

For the Sake of the Trach: Tracheostomy Basics & Complications in the ED

Clinical scenario: You’re working in the ED when you receive a pre-arrival page: 62 y M with trach in respiratory distress, unable to obtain sats, ETA 5 min.  As you are setting up suction in the resuscitation bay, EMS arrives with a pale, elderly male gasping for air.  What's your next move?

Review: Although (hopefully) not something we see in the emergency department every day, this is absolutely something we need to be comfortable stabilizing, if not definitively managing, on our own. In order to have a better understanding of tracheostomy complications, it’s important to understand some terminology and anatomy first.  

Differentiating tracheostomies from laryngectomies 
A critical piece of information to obtain in patients with a tracheostomy is to determine whether or not they have had a laryngectomy as well. A tracheostomy is simply an opening in the trachea created with an incision through the anterior neck. Some reasons for needing a tracheostomy include chronic mechanical ventilation, maxillofacial trauma, or upper airway obstruction such as from a mass. A laryngectomy—usually performed on patients with laryngeal cancer—is a complete removal of the larynx with separation of the airway from the mouth, nose, and esophagus. Since there is no connection between the mouth and the patient’s airway, laryngectomy patients can NEVER be orally
intubated. Outwardly, a laryngectomy patient looks like any other patient who has had a tracheostomy, so it is impossible to tell if a patient has had a laryngectomy simply by looking at his or her neck. While occluding the stoma of a patient who has only had a tracheostomy may not cause complete loss of the ability to ventilate (assuming that have at least a somewhat patent upper airway), occlusion of the stoma in a larygectomy patient will absolutely in all cases make it impossible for the patient to breathe, since the stoma is the only possible connection to the lungs in a laryngectomy patient. Despite being a “never” event, attempts at oral ventilation on a laryngectomy patient have been reported in the past [1].   If a patient with a total laryngectomy requires bagging and the trach tube is displaced, the stoma is the only way to ventilate them.  As an initial measure, an laryngeal-mask airway or neonatal mask can be applied to the stoma and used for bagging.


Tracheostomy basics 
To better understand tracheostomies in general, some basics are worth reviewing. Tracheostomies can be performed percutaneously at the bedside in the intensive care unit or surgically in the operating room. Various methods for a tracheostomy exist, but the neck incision is usually made midway between the cricoid cartilage and the sternal notch, well below where a cricothroidotomy is usually performed, and the trachea itself may be opened with a vertical or horizontal incision. A few safety features are sometimes integrated into the tracheostomy: stay sutures and Bjork flaps. Stay sutures are temporary sutures placed through 2-3 tracheal rings that allow for the trachea to be pulled back up to the skin should decannulation occur. This allows for visualization and easier reinsertion of the tracheostomy tube, thereby decreasing the risk of creating a false passage if the tracheostomy tube needs to be reinserted before the tract fully matures in about 7 days. Stay sutures are usually removed after 7 days, so patients presenting to the ED are not likely to have these. A Bjork flap is an upside-down U-shaped section of trachea that not only creates the tracheostomy, but the free edge of the flap is sutured to the skin of the neck, essentially creating a path for tracheostomy tube reinsertion and reduces the risk of creating a false passage when reinserting a tracheostomy tube prior to tract maturation [2]. 

Tracheostomy Tube Features 
Tracheostomy tube designs vary widely but most tracheostomy tubes have a number of parts in common. A few important details to know about every tube include the size of the tube, the brand or type, and whether or not the tube has a cuff. For example, when speaking with a consultant, one might say, “this patient has a size 6 cuffed Shiley.” The cuff is an important feature of many
tracheostomies as it allows for the airway to be sealed off, allowing for positive pressure ventilation and reducing the risk of aspiration. Deflating the cuff will allow the patient to breath through his or her mouth to some degree (assuming a patent upper airway), which serves as a backup for ventilation should the tube become occluded. Having the cuff down also allows for the patient to phonate when they occlude their tracheostomy tube, since air will be able to pass around the deflated cuff and tube through the vocal cords. Some tracheostomy tubes will have both an outer cannula and inner cannula, which allows for the inner cannula to be removed and cleaned or replaced without changing the entire tracheostomy tube. The downside to having an inner cannula, however, is that the effective inner diameter of the tube is decreased, so the patient may experience increased resistance to airflow.


Tracheostomy tube complications 
Setting up for the patient
Patients with tracheostomy tubes will on occasion present to our emergency department, and as the initial responders to these emergencies, it is important to be aware of the common or potentially life threatening complications associated with tracheostomy tubes. In the patient who is not rapidly decompensating, eliciting a brief history focused on the tracheostomy tube should be performed. Necessary details such as when the tracheostomy was placed, what size tube the patient uses, and why the tracheostomy was needed may be management altering pieces of information. When the patient arrives to the ED, supplies and equipment should be assembled in anticipation of potential worsening of the patient's complication. Personal protective equipment (face shield, gloves, fluid-resistant gown), suction catheters, Yankauer suction, replacement tracheostomy tubes (of the same and also one size smaller), tracheostomy tube ties, and a supplemental oxygen source should all be at the bedside ready for immediate use. Endotracheal tubes with intubating equipment (if the patient has a patent upper airway) should be readily available as well, if not at the bedside. 


Tracheostomy tube obstruction
Secretion buildup will often result in a narrowing of the effective tube diameter, commonly leading to increased resistance to flow and manifesting as respiratory distress in the patient. Inadequate suctioning, poor hydration, and decreased mobility are all risk factors for obstruction from secretions. The initial step in patients with a possible tube obstruction is to attempt passing a suction catheter through the tracheostomy tube. Instilling a few milliliters of sterile saline may help loosen secretions. If the suction catheter cannot be passed easily beyond a few centimeters or the length of the tube, the tube may either be obstructed or dislodged. In tubes with an inner cannula, the inner cannula should be removed and inspected or replaced, but if there is still resistance to passing a suction catheter, the tracheostomy tube is likely dislodged with the distal tip in the soft tissues of the neck and will need to be removed immediately and replaced [2]. 


Accidental decannulation
Although most patients will have a mature tracheostomy tract when they present to the ED, it is prudent to ask when the tracheostomy was placed. Tracheostomies that are less than 7 days old presenting with a decannulation of the tube should never be replaced blindly because of the risk of creating a false passage upon reinsertion. In a patient with a mature tract, he or she should be optimally positioned for reinsertion, preferably laying supine with a shoulder roll to extend the neck, which will help align the tissue planes and mimic the position by which the tracheostomy was originally created (likely supine on a operating table). Preoxygenating the patient oronasally or via the stoma will reduce the risk of oxygen desaturation should any difficulties arise during the procedure. Always use an obturator or introducer if available to avoid injuring the soft tissues with the end of the tracheostomy tube. Water-soluble lubricant or a lidocaine containing jelly should be applied to the tube. Holding the tube and obturator as one unit, the tube should be inserted with the tip initially pointed perpendicular to the stoma and then gently curved downward into the trachea following the bend of the tube. If the tube has been out of the stoma for more than several hours, the stoma may have begun to stenose and require dilation by an otolaryngologist prior to reinserting a tube. A chest x-ray should be performed to confirm placement. Alternatively, if available, a nasopharyngoscope or bronchoscope can be used to directly visualize the carina via the tracheostomy tube, which would guarantee proper tracheal placement.  For a video demonstration, see this you tube video.


Bleeding from the tracheostomy
Tracheostomy bleeds can be from a number of possible sources. Superficially, the skin underlying the flange of the tracheostomy tube should be checked, as malpositioning of the tube or patient may result in pressure ulceration. The tracheostomy tube may need to be removed to fully inspect the stoma and surrounding skin, and local bleeding can be controlled with pressure or topical silver nitrate. Often, granulation tissue, which are new growths of connective tissue and small blood vessels, can arise from the stoma site, or even within the trachea itself. Minor bleeding from around the stoma can similarly be treated with pressure or silver nitrate. Granulation tissue within the trachea is diagnosed by direct visualization with a nasopharyngoscope or bronchoscope, and needs to be definitively treated by ENT, usually by cauterization. Other potential sources of tracheostomy bleeding may come from the tube eroding into the thyroid vessels, thyroid gland, or tracheal wall. A tracheoinnominate fistula is perhaps the most feared complication of a tracheostomy tube and occurs when the tip of the cannula erodes through the anterior tracheal wall and into the innominate artery. This rare condition occurs in less than 1% of all patients with a tracheostomy tube but carries a mortality rate approaching 100% given the catastrophic bleeding into the airway. Approximately 75% of patients with a tracheoinnominate fistula will present within 3 to 4 weeks of tracheostomy tube placement, and some of these patients will have an initial "sentinel bleed" that may be relatively minor before developing massive hemorrhage [2,4]. Hemorrhage in these cases can be temporized by hyperinflating the cuff of the tracheostomy tube or endotracheal tube placed through the stoma as an attempt to tamponade the bleeding. These patients will need emergent thoracic and ENT consultation. Endovascular embolization of the innominate artery may be another option in these patients and has been demonstrated to be successful in a few case reports [5]. 


Cardiac arrest
Suppose a patient with a tracheostomy is brought into the emergency department with CPR in progress. Provided that the patient's stoma remains patent, a small cuffed endotracheal tube (e.g. a 6.0 tube) can be inserted through the stoma to ventilate a tracheostomy patient in this code scenario. Intubation of the stoma is not only is much faster than attempting oral intubation, but also avoids the potential attempt at oral intubation on a laryngectomy patient (which, again, should never occur) if his or her medical history is unknown. A laryngeal mask airway (LMA) can be placed over the stoma to ventilate if an endotracheal tube is not readily available, but the patient's mouth and nose should be covered if upper airway patency is unknown. Alternatively, should the stoma be stenosed (for example, if the tracheostomy tube has been out for hours) and the patient is known to have a patent upper airway, the stoma can be occluded and the patient can be ventilated with bag-valve-mask via the mouth and nose. 


Take Home Points 
Tracheostomy complications can quickly become life-threatening, and knowing some basic concepts about tracheostomies can allow us to better respond to and take care of patients with these complications. As with any patient, getting an adequate history should be the first step, and in particular, knowing if the patient has had a laryngectomy can prevent the “never event” of an orotracheal intubation attempt. Before performing any interventions on a patient where there is time to set up (i.e. on a relatively stable patient), one should gather appropriate equipment such as personal protective gear, extra tubes, and suction. Finally, consider the potential for a tracheo-innominate fistula in a bleeding tracheostomy patient given the extremely high associated mortality. 

Submitted by Phil Chan, PGY-3
Faculty Reviewed by jason wagner  (@TheTechDoc)
Everyday EBM Editor: Maia Dorsett (PGY-4, @maiadorsett) 

References

[1] El-Sayed IH, et al. Identifying and Improving Knowledge Deficits of Emergency Airway Management of Tracheotomy and Laryngectomy Patients: A Pilot Patient Safety Initiative. Int J Otolaryngology. 2010;2010:1-7.
[2] Morris LL, et al. Tracheostomy Care and Complications in the Intensive Care Unit. Crit Care Nursing. 2013;33(5):18-30.
[3] D. Doyle J, Scales DC. Tracheostomy. In: Hall JB, Schmidt GA, Kress JP. eds. Principles of Critical Care, 4e. New York, NY: McGraw-Hill; 2015. http://accessmedicine.mhmedical.com/content.aspx?bookid=1340&Sectionid=80032214. Accessed September 24, 2015.
[4] Epstein SK. Late Complications of Tracheostomy. Respir Care 2005;50(4):542-549.
[5] Hamaguchi S, Nakajima Y. J Vasc Surg. 2012;55:545-547

Saturday, October 17, 2015

@WUSTL_EM #EMConf: #FOAMed Supplement No. 17

1.  Core Content: Tick Born & Viral Illness
- emdocs covers Diagnosis and Treatment of Rocky Mountain Spotted Fever in the ED.
- What's the data surrounding tamiflu use for influenza?  EP Monthly reviewed it in this article and EM Lit of Note addressed here. The NNT.com also analyzed the numbers for treatment of influenza with tamiflu

2. Rural  & Farm Trauma
- Life in the Fast Lane discusses Trauma's Golden Hour.
- Here is a lecture from Free Emergency Medicine Talks about Farm Related Trauma.
- Refer to Life in the Fast Lane's post on management of open fractures to help with all those Auger-related injuries!

3. Difficult Case(s)
- Beware "unintentional blindness" - the "blocking" effect that occurs when you are performing a challenging task.  A great example is this NPR story on Why Even Radiologists Can Miss a Gorilla Hiding in Plain Sight.
- Radiopedia covers the LeFort Classification.
- The MayoClinic EM Blog covers management of Facial Trauma.
- Everyday EBM assesses the evidence surrounding antibiotics for mandibular fractures.
- EMCrit covers treatment of Aortic Dissection

4. Chest X-ray pathology - for a nice revew, work through this tutorial on Chest X-ray anatomy & pathology

5. Foot Problems
- Taming of the Sru covers the approach to the Foot X-ray.
- Use Northwestern's excellent Orthopedic Teaching site to cover Foot Cases.

Enjoy,
Maia  (@maiadorsett)

Saturday, October 10, 2015

@WUSTL_EM #EMConf: #FOAMed Supplement No. 16


1. Airway Cases - The Severe Asthmatic
- How to manage the ventilator once you've intubated: EMCrit on Ventilator Settings for the patient with obstructive airway disease. [MD]
- EM Rap covers Ventilator Basics in Ventilators 101  Part 1  and Part 2. [AR]
- Annals of Emergency Medicine covers whether Non-Invasive Positive-Pressure Ventilation Improve Outcomes in Severe Asthma Exacerbation? [MD]
- Annals of Emergency Medicine Systematic Review Snapshot covers whether IV Magnesium reduces hospital admission in patients with acute asthma. [MW]
- Our own blog covered the evidence regarding the use of ketamine in acute asthma exacerbation.

2. Termination of Resuscitation (in the Field)
- We recommend reading this retrospective study in JAMA regarding criteria for Prehospital Termination of Resuscitation for Cardiac Arrest.
- Journal of EMS covers Resuscitation past the 25 minute mark. [BS]
- This NPR story covers the post-resuscitation/death "Pause", making the ever-important case to stop what we are doing for a moment, not leave the room, and appreciate the person in the bed. [BF]

3. Emergency Deliveries
- Maternity Training International offers a wealth of educational resources (including instructional videos) to help you prepare for the emergency delivery. [MD]

4. C-spine Clearance
- A bit of an oldie for the FOAMed world, but here is a 2011 podcast from EMCrit on evaluation for C-spine injuries. [SM]
-(Free from EMRA members):  the July 2015 EM-RAP paperchase covers the most recent guidelines for C-spine clearance. [SM]
- Taming the Sru covers interpretation of C-spine CT. [SM]

Enjoy,
Maia Dorsett (PGY-4, @maiadorsett)
Sara Manning (PGY-4. @EM_SaraM)
Mike Willman (PGY-2)
Brendan Fitzpatrick (PGY-4)
Bridgette Svancarek  (EMS Faculty)
Adam Rieves (PGY-1)

Sunday, October 4, 2015

Gettin' jiggy wit it ... Stick a Catheter in it? Consider the Peripheral IJ.

Clinical scenario: You are taking care of a patient with a history of IV drug use who presents to the emergency department with a large abscess in her arm requiring drainage under conscious sedation. Nursing is unable to obtain IV access after multiple attempts. You look for an EJ or an ultrasound-guided peripheral IV and find no suitable sites. The patient is likely to be discharged so a central line seems unnecessary. You scope out the patient's neck under ultrasound and see the plump internal jugular (IJ) vein and wonder, why don't I just put an IV in that? 

Clinical Question: Is there any literature to support or refute the use of the peripheral IV in a central vein? 

Literature Review: In patients who are critically ill with difficult IV access, the decision to move forward with intraosseous or central venous access is relatively clear. However, stable patients requiring intravenous access that have no sites amenable to ultrasound guided peripheral IVs or external jugular access and are likely to be discharged present more of a conundrum.
One proposed alternative to placement of central venous access for these patients is the "peripheral IJ", an angiocatheter placed into the internal jugular vein. Anatomically speaking, a "peripheral IJ" is not a central line. Like the external jugular vein, which also drains into the subclavian, the catheter tip is far superior to the cavo-atrial junction and thus does not constitute central access. 

In 2009, a Letter to the Editor published in the Journal of Emergency Medicine described a technique in which the internal jugular was cannulated under ultrasound guidance with a 48 mm -peripheral angio catheter. The technique described involved the following steps: 

1. Place the patient in trendelenberg
2. Prep the neck with chlorhexadine as you would for a central line
3. Use a linear ultrasound probe covered in a sterile probe cover and sterile gel to identify the internal jugular vein
4. Cannulate the vein and advance catheter over needle
5. Flush & Dress with bio-occlusive dressing
No sterile drapes were used. 

In the report, the technique (anecdotally) had been safely performed many times, but presented no supporting data. 

Following this initial letter, two subsequent case series have been published supporting the peripheral-IJ as a reasonable alternative for temporary venous access. The first case series of 9 patients placed them in patients with unobtainable IV access [2]. 64 mm angiocatheters were used to cannulate the IJ under ultrasound guidance using the above-described technique. All catheters were labeled for removal within 72 hrs. All patients were followed up via chart review one year later. Two of 9 catheters failed due to kinking within the first 48 hrs. There were no apparent adverse outcomes in any patient including deep vein thrombosis, bacteremia, endocarditis or pneumothorax. A second group conducted a prospective case series in which 9 patients underwent placement of a ‘‘peripheral IJ” (PIJ), when other access could not be obtained and the patient did not initially require a central line [3]. The authors attempted follow-up with all patients within a week. On follow-up, the seven patients who were successfully contacted denied any fevers, chills, swelling or pain at the site of catheter entry. One likely reason for the decrease in complication rate is that the placement of a "peripheral IJ" does not require dilation of the vessel.

Take Home: In the patient with a need for short-term intravenous access and in whom ultrasound peripheral IVs or external jugular access cannot be obtained, consider placement of a peripheral-IJ. This procedure should be completed under sterile precautions above that used for standard ultrasound guided IV. Larger studies are needed to verify the safety of this technique on a broader scale. If you’re patient is morbidly obese (a common theme for difficult IV access) keep in mind that an even longer IV catheter may be required to keep it safely intravenous after placement.


Submitted by Daniel Kolinsky, PGY-3

Edited by Maia Dorsett (@maiadorsett), PGY-4
Faculty Reviewed by Evan Schwarz 

References
1. Moayedi S. Ultrasound-guided venous access with a single lumen catheter into the internal jugular vein. J Emerg Med 2009;37:419.

2. Zwank, M. D. (2012). Ultrasound-guided catheter-over-needle internal jugular vein catheterization. The American journal of emergency medicine, 30(2), 372-373.
3. Teismann, N. A., Knight, R. S., Rehrer, M., Shah, S., Nagdev, A., & Stone, M. (2013). The ultrasound-guided “peripheral IJ”: internal jugular vein catheterization using a standard intravenous catheter. The Journal of emergency medicine, 44(1), 150-154.

Thursday, September 17, 2015

@WUSTL_EM #EMConf: #FOAMed Supplement No. 15

 1. Kawaski's Disease and Other Pediatric Rashes
- Life in the Fast Lane covers Kawasaki's disease.  For a quick reference, you can also see ALiEM's Kawasaki PV card.  Peds EM Morsels also covered delayed diagnosis of  Kawasaki's disease in the post.
- WikiEM has some images of basic pediatric rashes.
- UMEM Educational Pearls breaks down rashes into those that involve the palms and soles, desquamate, and have a Nikolsky's sign (helps narrow differential).  I would add that asking if their is mucocutaneous involvement also helps narrow things down.

2. Neonatal Fever Not #FOAMed, but here are some links to the papers discussed by Indi Trehan during his talk:
     Who to tap?  Performance of Low - Risk Criteria in Evaluation of Young Infants with Fever. 
     If LP is indicated, how do you maximize your success?  Maximizing Infant Spinal Tap Success and Ultrasound Evaluation of Spinal Anatomy in Newborns
    Once the LP is done, what do you treat with?Listeria and Enterococcal Infections in Patients 28 days and Younger - Is Ampicillin still indicated?

For #FOAMed resources:
Emergency Medicine Cases addresses pediatric fever without a source.  
PEM Currents Podcast covered The Febrile Newborn.

3. Tumor Lysis Syndrome & Other Oncologic Emergencies
- Test yourself on Tumor Lysis Syndrome basics with this Life in the Fast Lane post.
- emdocs covers Oncologic Emergencies in these posts:  Oncologic Emergencies I and Oncologic Emergencies II.
- Not really #FOAMed, but a good review.  Emergency Medicine Clinics of North America covered "Management of Pediatric Tumor Lysis Syndrome in the Emergency Department".
- Check out this interesting case related to hyperleukocytosis from Life in the Fast Lane.
- UMEM Pearls covers management of hyperleukocytosis/blast crisis

4.Tracheostomy Complications
 - See the Life In the Fast Lane Tracheostomy page .
 -  Management of respiratory distress in the tracheostomy patient as covered by  emdocs and First 10 in EM.

5.  UTI treatment in the ED
- Blake Bruton recommends this article from Emergency Medicine News entitled "Urine Dipstick testing: Everything You Need to Know."
- Best Evidence Topic Reports covers the sensitivity (or lack thereof) of the bedside urine dipstick in ruling out UTI in patient's who presents with urinary symptoms.

Enjoy,
Maia (@maiadorsett)

Monday, September 14, 2015

@WUSTL_EM #EMConf: #FOAMed Supplement No. 14


Welcome to @WUSTL_EM #EMConf, the #FOAMed Edition. The purpose of this weekly column is to identify #FOAMed resources that reinforce and expand on the concepts/facts discussed during weekly conference. Please post additional resources as comments below or tweet to @WUSTL_EM.


1. Core Content - Eye Emergencies
Dr. Philip Chan @PhilChan86 provided high yield information on causes of vision loss, a topic covered in the always helpful Life in the Fast Lane. Afterwards, head over to Academic Life in EM and work through the AIR Series, HEENT module, covering topics like "The Red Eye" and ocular ultrasound.

2. The Man and the Machine
Dr. Sean Cavanaugh gave us an amazing lecture covering his approach to LVAD patients, and how to troubleshoot common problems.  Summary? #Treat_The_Pt_Then_The_Machine


For more, head over to ED ECMO and get the basics from a review article by Dr. Partyka.

Once you have an idea about how LVAD's work, learn how to troubleshoot managing the crashing LVAD patient. Head over to EM Crit for a podcast and then to the Maryland CC project for video lecture. 

3. Approach to chest xrays
The Resident Focker family gave us a practical approach to chest xrays. Summary? #Haveasystem.  

A quick pocket tool for reading chest xrays can be found at Life in the Fast Lane. If you are an intern and new to radiographs, perhaps start with an interactive learning tool by Dr. Lieberman

4. QI: Early Septic shock, Sedation troubleshooting
Dr. Oberle reviewed the topics of early sepsis management, and common ED sedation complications. 


Dr. Oberle commented on recent publications regarding the benefit of earlier antibiotics in sepsis, see last weeks. #FOAM supplement for reference. In addition,  EM Lit of Note is also questioning the survival benefit. 

Want to be a master of the ED procedural sedation ? Start by using a Sedation checklist by EM Updates, then go on to watch the Sedation Trilogy  for sedation troubleshooting tips 

5.  Msk review: The foot part 1
Dr. Joy English gave us a nice introduction on foot injuries. Summary? #Useyourtools. Check out the The Ultrasound Site where they cover ultrasound diagnostics to potential foot and ankle injuries. 

The dude abides,

Louis Jamtgaard PGY-4
@Lgaard


Wednesday, September 2, 2015

@WUSTL_EM #EMConf: #FOAMed Supplement No. 13


Welcome to @WUSTL_EM #EMConf, the #FOAMed Edition. The purpose of this weekly column is to identify #FOAMed resources that reinforce and expand on the concepts/facts discussed during weekly conference. Please post additional resources as comments below or tweet to @WUSTL_EM.

1. Core Content - Eye Emergencies
-  EM Lyceum reviews topical anesthetics for corneal abrasions, timing of follow-up for patients with floaters, and the use of ultrasound to assess intraocular pressure in this post.
- Check out the Root Atlas, the "internet's best eye videos", for some instructional videos for procedures such as foreign body removal [this website really is awesome]. 

2. Sepsis in the Prehospital Arena
- One of our residents, Michael Willman, suggested this meta-analysis on affect of antibiotic timing on mortality in severe sepsis and septic shock.
- Consider reading this commentary by Alan Jones' group on the challenges of prehospital sepsis detection.
- See the July 2015 WashU Journal Club summary of studies evaluating early goal directed therapy for the treatment of severe sepsis and septic shock.
- Want to support research? Check out the Crowdfunding Page for development of the "Think Sepsis" tool at the University of Pittsburgh for prehospital sepsis recognition.

3. Neuro MRI protocols
-See this article regarding the increase in MRI exams performed through the emergency department
- Emergency Medicine Cases covers Low Back Pain Emergencies in the ED
- Our own blog covers the sensitivity of imaging studies for diagnosis of CSF shunt malfunction
- Review indications for critical and urgent MRI exams, as well as the correct exam for the indication:
4. Aortic Syndromes & Ultrasound
- Test yourself with Ultrasound Case of the Week #55 and #49.
- EM Curious Ultrasound Leadership Academy covers Aortic Ultrasound
- UMEM Education Pearls covers the suprasternal notch view for detecting aortic dissection.

5. Trauma Simulation -
- I've posted the link to Cliff Reid's talk on Making Things Happen many times, but I'm posting it again because if you haven't watch it yet, then do so now.
- Wash U EM Journal Club covered TXA in treatment traumatic hemorrhage, and the findings were nicely summarized in this article by our own Wes Watkins, Brian Cohn and Bill Dribben in epmonthly.
-ER Cast covers management of neurogenic shock.

Enjoy,
Maia (@maiadorsett)

Sunday, August 30, 2015

The Times They Are A Changin': the "No Zone" Approach to Management of Penetrating Neck Trauma

Clinical Case: You're working a busy evening shift when a middle aged woman is brought in by EMS from the scene of a car accident.  She has a deep laceration to her anterior neck near the level of the cricoid cartilage from a glass shard.  She is neurologically intact, talking with a normal voice and is in no respiratory distress.  However, there is a continuous and brisk oozing of blood from the wound.

Clinical Question: What imaging is indicated in hemodynamically stable, neurologically intact patients with penetrating neck injuries?  What should the typical disposition be?

Literature Review:
Any neck wound that extends deep to the platysma is considered a penetrating neck wound, and it is estimated that they represent 5-10% of all trauma patients who arrive to the emergency department. Two common ways of anatomically dividing the neck include using the sternocleidomastoid to divide the neck into anterior and posterior triangles, or dividing the neck into three zones [1]:


    In the event of penetrating injury to the neck, airway compromise should be immediately assessed, with early intubation for airway protection if there is any concern for expanding neck hematoma or concerns for airway injury.  An attempt can be made to orotracheally intubate (bougies have been suggested as excellent initial adjuncts [2]), but plans should be made to move to early cricothyroidotomy if the airway is unable to be secured from above. After securing the airway and establishing hemodynamic stability, the neck wound should be carefully inspected.  Injuries that breach the platysma may have caused significant underlying injury, and it is best to avoid probing these wounds at the bedside, as this could disrupt hemostasis.  Aside from risk of vascular disruption, patients with penetrating neck injuries warrant consideration of tracheal and esophageal compromise.  Signs of tracheal injury include air bubbling at the wound, hemoptysis, subcutaneous emphysema, and stridor.  Esophageal injuries can be initially be asymptomatic, and a missed injury can lead to neck space infection and mediastinitis [3].   Emergent surgical consultation is warranted, as patients with hemodynamic instability and/or "hard signs" of vascular or aerodigestive tract injury should go for emergent neck exploration [3].

    Classically, management of hemodynamically stable patients with penetrating neck injuries was based on an anatomic "zone-based" approach mentioned above, with zone II injuries often going directly to surgical exploration and zone I and III injuries undergoing angiography, bronchoscopy, and esophagoscopy.  This approach was developed in the 1970’s, but it had several problems [4].  First, there may be poor correlation between the location of the neck wound and internal organ involvement, as there may be traversing of zones internally. Secondarily, the adoption of a mandatory-exploration policy lead to a high negative exploration rate (53% - 56%)[4,5].

    With the rapid improvement and dissemination of the use of  CT over the past few decades, a “No Zone” management approach based on careful physical exam with CT angiography has been shown in surgical literature to decrease resource utilization and unnecessary surgical exploration, making the rigid zone approach less relevant [3].   Several studies have examined the sensitivity and specificity of CT angiography in stable patients with penetrating neck injury.  A study by Inaba et. al. prospectively evaluated an algorithm in which patients with "soft signs" of injury (venous oozing, non-expanding hematoma, minor hemoptysis, dysphonia, dysphagia, or small amount of subcutaneous emphysema) underwent an initial evaluation with CT-angiography and asymptomatic patients were observed [6].  Over a 31-month period, 453 patients with penetrating neck trauma were prospectively evaluated in their study.  186 of these patients had "soft signs" of clinical injury, and underwent CT angiography as their initial method of evaluation.  38.2% of these patients had an injury to zone II of the neck.  Using an aggregate gold standard of the final diagnosis at discharge which included operative exploration, catheter-based angiography, bronchoscopy, esophagogram and esophagoscopy results and clinical follow-up (duration not specified),  the sensitivity and specificity of CT Angiography for vascular or aerodigestive injury was 100% and 97.5 % respectively.  There were two patients who had false-positive findings of vascular injury (irregularities in the ICA) that were not present on follow-up with surgical exploration and/or angiography, and three patients had air tracking suspicious for aerodigestive tract injury that was not confirmed on follow-up imaging and endoscopic studies. 

    As mentioned above, the "No Zone" approach combining clinical exam with imaging evaluation has the potential to decrease unnecessary neck exploration. A study by Osborn et. al. examined the rate of negative neck explorations in patients who were taken to the OR who did not have hard signs of injury.  They compared the rate of negative neck explorations amongst those patients who had a CT-A as part of their initial evaluation and those who did not, and found that CT angiography significantly reduced the negative neck exploration rate [7]:

    Source: Osborn et al. (2008)
     In their review of penetrating neck trauma management, Shiroff at al. shared the algorithm below, comparing the traditional vs. "no zone" approach:

    Image Source:  Reference 3



    Take Home Points: Patients with penetrating neck trauma who are hemodynamically unstable or  display hard signs of vascular or aerodigestive should receive immediate surgical consultation with consideration for operative or invasive management.  As the traditional, anatomic approach to management of penetrating neck trauma is associated with a high rate of negative neck exploration, patients with soft signs of injury should be initially evaluated with CT angiography which has a high sensitivity for clinically-significant injury.

    Submitted by Philip Chan, PGY-3
    Edited by Maia Dorsett (@maiadorsett), PGY-4
    Faculty reviewed by jason wagner (@TheTechDoc)

    References
    [1] Tintinalli’s Emergency Medicine, 7e.  Ch 257. 
    [2] Daniel, Y., de Regloix, S., & Kaiser, E. (2014). Use of a Gum Elastic Bougie in a Penetrating Neck Trauma. Prehospital and disaster medicine, 29(02), 212-213.
    [3] Shiroff, A. M., Gale, S. C., Martin, N. D., Marchalik, D., Petrov, D., Ahmed, H. M., ... & Gracias, V. H. (2013). Penetrating neck trauma: a review of management strategies and discussion of the ‘No Zone’approach. The American Surgeon, 79(1), 23-29.
    [4] Prichayudh, S., Choadrachata-anun, J., Sriussadaporn, S., Pak-art, R., Sriussadaporn, S., Kritayakirana, K., & Samorn, P. (2015). Selective management of penetrating neck injuries using “no zone” approach. Injury.
    [5] Varghese, A. (2013). Penetrating neck injury: a case report and review of management. Indian Journal of Surgery, 75(1), 43-46.
    [6] Inaba, K., Branco, B. C., Menaker, J., Scalea, T. M., Crane, S., DuBose, J. J., ... & Demetriades, D. (2012). Evaluation of multidetector computed tomography for penetrating neck injury: a prospective multicenter study. Journal of Trauma and Acute Care Surgery, 72(3), 576-584.
    [7] Osborn, T. M., Bell, R. B., Qaisi, W., & Long, W. B. (2008). Computed tomographic angiography as an aid to clinical decision making in the selective management of penetrating injuries to the neck: a reduction in the need for operative exploration. Journal of Trauma and Acute Care Surgery, 64(6), 1466-1471.

    Thursday, August 27, 2015

    Consultant Teachings No. 4: "I'm Dizzy"

     
    Clinical Scenario: It’s 3 AM in the ED when a 70 year old male with a history of hypertension comes in complaining of dizziness. You spend 10 minutes trying to get him to describe his dizziness, getting various descriptions of “lightheaded”, “spinning”, “imbalanced”, with him eventually saying “I’m just dizzy doc!!!”. The dizziness was described as sudden onset and had been constant for an hour, but had spontaneously resolved on arrival to the ED. During the episode, he had difficulty standing and stated that it felt like he would fall if he "didn’t hold onto something". He also noted some mild nausea and diaphoresis. Finally, he complained of a headache, though he has a long history of similar headaches. His initial head CT showed no acute process. 

    Clinical Question: How do you evaluate a patient with acute dizziness?

    Discussion & Literature Review

    Dizziness and vertigo make up about 4% of chief complaints in the emergency department (ED) [1]. This chief complaint can be caused by pathology in many different body systems, and that pathology can range from benign to acutely life-threatening. For patients presenting to an ED with dizziness, affected systems include otologic/vestibular (32.9%), cardiovascular (21.1%), respiratory (11.5%), and neurologic (11.2%) as the top four diagnostic groups [2].

    Dizziness Conundrum: Despite dizziness being a relatively common complaint, it can be very challenging to work up and manage. Traditional teaching on the evaluation of dizziness is to rely heavily on the quality of the dizziness, whether it is “spinning”, “lightheaded” or other similar descriptors [3]. However, this has been shown to be an ineffective means of establishing a differential diagnosis and may lead to dangerous misdiagnosis. Emergency department physicians (including residents) have been specifically studied and found to demonstrate over-reliance on symptom quality leading to subsequent high-risk reasoning [4,5]. There is also evidence that patients with the two most common vestibular disorders (benign paroxysmal positional vertigo (BPPV) and acute peripheral vestibulopathy) are often managed sub-optimally both in terms of diagnostic testing and prescribed treatment in the ED [6]. These studies suggest an opportunity to improve the emergency management of dizzy patients. 


    History is Everything In the Dizzy Patient: As in all of medicine, obtaining an accurate and useful history is the single most important step in establishing the diagnosis of a patient with dizziness. The quality of dizziness lacks specificity in ED patients; one study found that patients describe their dizziness in multiple ways if given multiple options, may change their description of the dizziness if asked again only 5-10 minutes after initial questioning, and answer open-ended questions with vague or circular answers [7]. 

    As opposed to the quality of symptoms, patients have been found to more reliably answer questions about the timing and triggers of their dizziness. This had led to the formulation of the “timing and triggers” model of history taking in the evaluation of a dizzy patient [8]. The goal of history-taking in this model is to identify the patient as having one of four syndromic patterns of dizziness:

    · acute, spontaneous, prolonged (also known as the acute vestibular syndrome) 
    · episodic, positional 
    · episodic, spontaneous 
    · chronic unsteadiness [8]. 

    When asking about timing, attempt to clarify whether the dizziness is sudden or gradual onset, episodic or continuous, the duration of symptoms, and the frequency of symptoms. If the symptoms are episodic, clarify how long each episode lasts (seconds, minutes, hours, days) and make sure to ask if they completely return to normal between episodes or if they have constant symptoms with exacerbations. When asking about triggers, it is important to define true triggers as opposed to exacerbating factors. A common exacerbating factor is any form head movement, which generally worsens all forms of acute vestibular dizziness, so does not often help establish a diagnosis. However, if specific movements (i.e. rolling over in bed or changing posture) trigger the dizziness, this can lead to a diagnosis.  

    Examination Tools and Tips: On physical examination, general medical and neurologic screening exams are important. Focal abnormalities on these exams may suggest a diagnosis (i.e. unilateral weakness or ataxia may suggest stroke, new cardiac murmur may suggest myocardial infarction or aortic dissection). However, there are specific physical exam maneuvers that can also be performed. The most commonly employed is the Dix-Hallpike maneuver to evaluate for benign paroxysmal positional vertigo (BPPV). This should be employed only if the patient describes episodic dizziness. The Dix-Hallpike maneuver will worsen the already-present spontaneous nystagmus during the acute vestibular syndrome, but this should not be taken as a positive test. The other test an ED provider should be familiar with is the HINTS-Plus exam [9]. This is a three step test of skew deviation, nystagmus, and head impulse testing (video links to a positive head impulse test, which suggests a peripheral etiology) combined with an assessment for unilateral hearing loss. This test is concerning for a central etiology with the presence of skew deviation, direction changing or vertical nystagmus, a negative head impulse test, and/or new unilateral hearing loss. In the evaluation of the acute vestibular syndrome, this bedside test is more accurate in the acute setting than MRI for diagnosing a posterior circulation stroke. Another physical exam pearl is that some patients can suppress nystagmus with visual fixation, so removing fixation can bring out their nystagmus. An easy way to do this is to turn off the lights and use your ophthalmoscope, which will block fixation and give you a magnified view of the eye for easier visualization of the nystagmus.

    Summary and differential diagnosis: Once a patient’s complaints have been characterized by history as one of the four syndromic patterns discussed above, the differential diagnosis is much more limited. The physical examination assesses for specific diagnoses, which then guides further workup and treatment.


    Source: Newman-Toker, D. E., Symptoms and signs of neuro-otologic disorders, Continuum (Minneap Minn), 2012, 18(5 Neuro-otology):1016-1040.


    Submitted by Alex Dietz, Neurology PGY-4
    Faculty Reviewed by Peter Panagos
    Everyday EBM Editor: Maia Dorsett, PGY-4

    References
    [1] Saber Tehrani, A. S., Coughlan, D., Hsieh, Y. H., Mantokoudis, G., Korley, F. K., Kerber, K. A., Frick, K. D., et al., Rising annual costs of dizziness presentations to U.S. emergency departments, Acad Emerg Med, 2013, 20(7):689-696.
    [2] Newman-Toker, D. E., Hsieh, Y. H., Camargo, C. A., Pelletier, A. J., Butchy, G. T. and Edlow, J. A., Spectrum of dizziness visits to US emergency departments: cross-sectional analysis from a nationally representative sample, Mayo Clin Proc, 2008, 83(7):765-775.
    [3] Kerber, K. A. and Newman-Toker, D. E., Misdiagnosing Dizzy Patients: Common Pitfalls in Clinical Practice, Neurol Clin, 2015, 33(3):565-575.
    [4] Newman-Toker, D. E., Charted records of dizzy patients suggest emergency physicians emphasize symptom quality in diagnostic assessment, Ann Emerg Med, 2007, 50(2):204-205.
    [5] Stanton, V. A., Hsieh, Y. H., Camargo, C. A., Edlow, J. A., Lovett, P. B., Lovett, P., Goldstein, J. N., et al., Overreliance on symptom quality in diagnosing dizziness: results of a multicenter survey of emergency physicians, Mayo Clin Proc, 2007, 82(11):1319-1328.

    [6] Newman-Toker, D. E., Camargo, C. A., Hsieh, Y. H., Pelletier, A. J. and Edlow, J. A., Disconnect between charted vestibular diagnoses and emergency department management decisions: a cross-sectional analysis from a nationally representative sample, Acad Emerg Med, 2009, 16(10):970-977.
    [7]Newman-Toker, D. E., Cannon, L. M., Stofferahn, M. E., Rothman, R. E., Hsieh, Y. H. and Zee, D. S., Imprecision in patient reports of dizziness symptom quality: a cross-sectional study conducted in an acute care setting, Mayo Clin Proc, 2007, 82(11):1329-1340.
    [8] Newman-Toker, D. E., Symptoms and signs of neuro-otologic disorders, Continuum (Minneap Minn), 2012, 18(5 Neuro-otology):1016-1040.
    [9] Saber Tehrani, A. S., Kattah, J. C., Mantokoudis, G., Pula, J. H., Nair, D., Blitz, A., Ying, S., et al., Small strokes causing severe vertigo: frequency of false-negative MRIs and nonlacunar mechanisms, Neurology, 2014, 83(2):169-173.
     

    Title Image source: wikipedia.

    Friday, August 21, 2015

    @WUSTL_EM #EMConf: #FOAMed Supplement No. 12

    Welcome to @WUSTL_EM #EMConf, the #FOAMed Edition. The purpose of this weekly column is to identify #FOAMed resources that reinforce and expand on the concepts/facts discussed during weekly conference. Please post additional resources as comments below or tweet to @WUSTL_EM.


    1. Evaluation of Pediatric Abdominal Pain
    - Don't Forget the Bubbles had this post on the differential diagnosis for obstruction in the pediatric population.
    - Our own EM Journal club covered non-operative management of pediatric appendicitis.
    - St. Emlyn's covers the spectrum of pediatric emesis 
    - FOAMcast covers pediatric GI emergencies.
    - Test your pediatric X-ray prowess with this series of cases of obstruction vs. ileus.

    2. Interesting Case Conference - Rocky Mountain Spotted Fever
    - A good review on the Emergent Diagnosis of the Unknown Rash, including the deadly causes.
    - Crashing Patient covers Tick-Born Illnesses

    3. Neonatal Sepsis
    - PEM blog reviews the evidence surrounding procalcitonin as a marker of serious bacterial infection in the febrile newborn and you can listen to a podcast about the febrile newborn.

    4. Intraparenchymal Hemorrhage - EM Lyceum provides this comprehensive review on emergency management of ICH.

    5. Pelvic Inflammatory Disease
    - New England Journal of Medicine published this recent review on Pelvic Inflammatory Disease.
    - EM Lyceum covers the history & physical exam findings, diagnostic workup & management of PID.

    Enjoy,
    Maia Dorsett (@maiadorsett)

    Sunday, August 16, 2015

    On Broken Teeth: Emergency Management of Dental Fractures

    Clinical Scenario: One evening in the ED, a teenage boy is brought in by his mother for dental trauma after an altercation at school.  The boy reports that he was pushed to the ground in the scuffle, hitting face first into the concrete. On exam, pinkish-red material was visible at base of what remains of his frontal incisorsIt's been awhile since you took care of dental trauma and you decide to read more about it. 

    Clinical Question: What are the different layers of teeth and how do they impact severity of dental injury? What are the risk factors for dental injury? How are dental fractures graded and what steps should the ED physician take to protect remaining tooth fragments? 

    Source: wikipedia.org
    Review: Traumatic dental injuries (TDI) are a common occurrence in both children and adults. Approximately 1 in 3 adults sustain dental trauma during their lifetime, the majority which occur in childhood. A wide variety of risk factors have been described in the literature. These include patient specific factors like ADHD, epilepsy, cerebral palsy, propensity for risk-taking behavior, and anatomic factors like over-jet (the horizontal distance between posterior surface of the maxillary incisors and the anterior surface of the mandibular incisors) and inadequate lip coverage. In a review of rates of TDI in epileptic patients, over half had suffered TDI, many with multiple injuries. Environmental factors include poor socioeconomic status, living in an overcrowded environment and poor road safety [1]. Etiologies of TDI are broad with the most common mechanism of injury being falls. Adolescents and adults are more likely to sustain TDI through organized sporting activities, traffic accidents and violent means including fighting and assault.  In children, dental fractures can be a presentation of non-accidental trauma, and therefore a complete a full physical exam, including skin exam, should be performed

    With regard to anatomy, primary dentition consists of 20 teeth – 8 incisors, 4 canines and 8 molars, classically lettered A – T. The permanent dentition includes 28 to 32 teeth – 8 incisors, 4 canines, 8 premolars and 8 - 12 molars. The 32 permanent teeth are numbered from right to left on top and left to right on the bottom [2].

    With regard to anatomy of the individual teeth, from the inside out a tooth is composed of pulp, dentin and enamel [2]. The visible portion of the tooth is referred to as the crown and consists all three layers. As the tooth extends underneath the gum line, the enamel portion thins and the dentin and pulp extend in to the alveolar bone covered by a thin layer of cementum. The apex of the tooth is the entry point of the neurovascular bundle supplying each tooth. Finally,  the periodontal ligament is a collagenous strructure that extends from the alveolar bone to the cementum surrounding the root of the tooth.


    Image source: Tintinalli, JE et al: Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 7th Ed via Accessmedicine.com
    The primary traumatic dental injury classifications are concussion, subluxation, extrusion, luxation, intrusion, avulsion and fracture [3].  Examination of a TDI should include visual inspection, percussion testing, manual evaluation of tooth mobility and consideration for radiographic imaging to evaluate for associated alveolar bone injury and widening of the periodontal ligament space. Sensitivity testing (cold testing) is often less useful at the time of injury due to transient lack of pulpal response.   

    Dental fractures aka "broken teeth" require different management based on the extent of the injuryThe Ellis classification, which subdivides dental fractures into three classes of injury is useful for ED providers because it determines emergent care of the dental fracture [4]: 
                  -    Ellis I fractures involve only the enamel.  They typically require no emergency treatment. If sharp edges are present, those can be smoothed for patient comfort. Dentist follow up can be at the patient’s convenience.
                  -    Ellis II fractures involve the dentin but not the pulp  and  can be identified on exam by the creamy yellow color of dentin compared to the whiter, harder enamel.  These fractures require more urgent care.  Because dentin is a microtubular structure, Ellis II fractures threaten the integrity of the pulp and can lead to contamination of the pulp by oral flora . After recognizing an Ellis II fracture, the ED provider should anesthetize, clean and dry the tooth (Peridex can be used to sterilize the tooth) and seal the exposed dentin, which can be done with dental cement . Urgent dental follow up in the next 24 hours is recommended. Patients will require frequent visits and radiographs.
                  -   Ellis III fractures are full thickness and expose the pulp.  They can be identified by visualization of the pink-red pulp as well as bleeding from the pulp on cleaning of the tooth. Like Ellis II injuries, the pulp is at risk with these injuries but at a greater extent given the direct exposure of pulp to the oral environment. Ellis class III injuries require a two step sealing procedure. After anesthetizing, cleaning and drying the tooth, bleeding should be controlled with careful direct pressure. The first sealant layer is a calcium hydroxide base. On top of this base, the same dental cement coverage is applied. Like Ellis II injuries, Ellis III injuries require urgent dental follow up preferably within 24 hours.   

    For children with injuries to primary teeth, pulp exposure is more often encountered given the relatively larger size of the pulp. The same approach to different fracture types are recommended for children. Children will often require a pulpotomy to better protect the pulp from infection, but this requires more specialized tools and can be performed by the dentist in rapid follow up.

    Because dental fractures can have associated injuries, it is important to examine for associated intraoral lacerations, tooth subluxation or avulsion. Subluxations and avulsions may require repositioning of the tooth and splinting to adjacent teeth with zinc oxide based dressings like Coe-Pak  [little trick of the trade: since the applications of dental splints requires teeth to be dry, cut off the end of oxygen tubing and attach to the air or oxygen on the wall to blow air onto the teeth and dry them prior to application of an adhesive dental splint]. 

    With all of these injuries, patients should be discharged with oral analgesics, a soft diet and urgent dental follow-up. Generally, topical anesthetics should be avoided. Routine use of systemic antibiotics has not demonstrated benefit, but patient specific factors, associated injuries and co-morbidities should be considered [5].    
      
    Take-Home Points:  Dental fracture management depends on the Ellis classification. Anything more than an Ellis I fracture requires some degree of a protective coating applied in the ED and referral to urgent dental follow up.  Always examine patients thoroughly for other associated injuries and watch for NAT. 

    Submitted by Sara Manning (@EM_SaraM), PGY-4
    Faculty Reviewed by Rob Poirier

    Everyday EBM Editor: Maia Dorsett (@maiadorsett)  

    In case you were thinking that "Broken Teeth" would be a good name for a band, it's already taken.  Thank you google.  

    References:
    1. Glendor, U, “Aetiology and risk factors related to traumatic dental injuries a review of the literature.” 2009. Dental Traumatology. Vol 25: 19 – 31. 
    2. Tintinalli, JE et al, : Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 7th Ed via Accessmedicine.com 
    3. Dentaltraumaguide.org
    4.DiAngelis et al, “International Association of Dental Traumatology guidelines for the management of traumatic dental injuries: 1. Fractures and luxations of permanent teeth.” 2012 Dental Traumatology. Vol 28: 2 – 12. 
    5. ANDREASEN, J. O., STORGÅRD JENSEN, S. I. M. O. N., & SAE‐LIM, V. A. R. A. W. A. N. (2006). The role of antibiotics in preventing healing complications after traumatic dental injuries: a literature review. Endodontic Topics, 14(1), 80-92.

    Theme Image Source: http://www.windsorstar.com