UMEM Educational Pearls

There is little debate that ultrasound-guided central lines are safer, faster, and more reliable compared to a landmark technique; there is some debate, however, as to whether the short axis (SA) or long axis (LA) approach is the best (see clips below).

The referenced study compared the SA and the LA technique for both the internal jugular (IJ) and subclavian (SC) venous approach. The authors measured number of skin breaks, number of needle redirections, and time to cannulation for each method.

This study demonstrated that the LA technique for subclavian placement had fewer redirections, decreased cannulation time, and fewer posterior wall punctures as compared to the SA. With respect to the IJ approach, the LA was also associated with fewer redirections than the SA view.

Bottom line: Consider the long-axis technique the next time you place an ultrasound guided central line.

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Ischemic ECG Findings: Significance of the U-wave

The U-wave is a small deflection immediately following the T-wave, commonly with the same polarity as the T-wave and most prominently seen in precordial leads V2–V3.

Prominent U-waves are most often seen with bradycardia and hypokalemia, but can also be secondary to other electrolyte imbalances and medications.

Typically, T- and U-wave polarities are concordant; discordant U-waves have been identified several hours prior to other ECG changes in acute myocardial infarction.

Some studies note that exercise induced U-wave inversion is highly predictive of CAD; negative U -waves in the precordial leads during exercise had a higher specificity (88% vs. 70%) & positive predictive value (77% vs. 61%) for ischemia than ST-depression.

Reinig et al. 2005 showed that negative concordance of T- and U-waves have poor prognosis & is quite specific for ischemia.

·      ECG’s were divided into 3 groups:

o   Type 1 T-U discordance (negative T waves + positive U waves)

o   Type 2 T-U discordance (positive T waves + negative U waves)

o   Negative T-U concordance (both T & U waves negative)

* Significantly higher rate of CAD (88% vs. 58%) (P-value <. 0001) in the negative T-U concordance group 

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Posterior Shoulder Dislocations are uncommon (strong supporting structures vs. anterior)

But commonly missed by physicians

Mechanism: Direct blow anterior shoulder/FOOSH with shoulder internally rotated and ADDucted)

May also see with seizure/electric shock (tetanic contraction)

Clinical findings subtle

Shoulder held in ADDuction and internal rotation. Patient unable to externally rotate arm from this position. If habitus allows, anterior shoulder depression/posterior fullness.

Radiology: Decreased overlap between humeral head and glenoid fossa. Proximal humerus fixed in internal rotation looks like a light bulb on a stick.

Y view will show subtle posterior displacement of humeral head (not as dramatic as is in anterior dislocations!)

http://cdn.lifeinthefastlane.com/wp-content/uploads/2009/06/posterior_shoulder_dislocation_005.jpg

http://eorif.com/Shoulderarm/Images/Shoulder-dislocationP1.jpg

Background

In addition to the down regulation of GABA receptors in chronic ethanol users, there is an upregulation in NMDA receptor subtypes. Although the pathophysiology is much more complex, when ethanol abstinence occurs, there is a shortage of GABA-mediated CNS inhibition and a surplus of glutamate-mediated CNS excitation. If GABA agonists are the mainstay of treatment, why not also target the NMDA receptor? Enter ketamine.

The Data

Only one study exists and was published recently.

• Retrospective review of 23 adult patients administered ketamine specifically for management of AWS.
• Mean time to initiation of ketamine from first treatment of AWS, and total duration of therapy were 33.6 and 55.8 hours, respectively.
• Mean initial infusion dose and median total infusion rate were 0.21 and 0.20 mg/kg/h, respectively.
• No change in sedation or alcohol withdrawal scores within 6 hours of ketamine initiation.
• Median change in benzodiazepine requirements at 12 and 24 hours post-ketamine initiation were -40.0 and -13.3 mg, respectively.
• One documented adverse reaction of oversedation, requiring dose reduction.
• Authors concluded that ketamine appears to reduce benzodiazepine requirements and is well tolerated at low doses.

Application to Clinical Practice

While the dexmedetomidine studies should not be using reduction in benzodiazepine requirements as an endpoint, it may be acceptable for ketamine since it actually works on the underlying pathophysiology. More studies are needed but it's good to see we’re starting to look at it.

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Introduction:

There were approximately 56 million deaths worldwide in 2012. The causes of death vary significantly based upon the income level of the country.

High-income Countries:

• 7 out of 10 deaths were among individuals 70 years or older
• Only 1 in 100 deaths were in children under 15 years
• Most deaths were due to chronic diseases, such as cardiovascular diseases, cancer, dementia, COPD or diabetes

Low-income Countries:

• Only 2 of every 10 deaths were among individuals 70 years or older

• Almost 4 of every 10 deaths were among children under 15 years
• People frequently die of infectious diseases, such as lower respiratory infections, HIV/AIDS, diarrheal diseases, malaria and tuberculosis.
• Complications of childbirth are also among the leading causes of death

Bottom Line:

Acute care services in the US and high-income countries need to acknowledge the growing number of individuals with chronic diseases and the rapidly growing elderly population. In low-income countries, acute care services still need to primarily address maternal/child infections and problems as well as infectious diseases.

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Safety of Thoracentesis

• Thoracentesis is routinely performed in both acute and non-acute patients while patients are admitted to the hospital for respiratory distress
• A recent 12 year cohort study of 9320 thoracenteses was published from Cedars-Sinai Hospital
• The clinicians that perform these procedures are well experienced
• The most common complications include pneumothorax, re-expansion pulmonary edema, and bleeding

Results after 24 hours of followup post-procedure

• 0.61% of iatrogenic pneumothoraces
• 0.01% rate of re-expansion pulmonary edema
• 0.18% of bleeding episodes

Other interesting points:

• Pneumothorax was associated with removing >1500 mL of fluid and more than one needle pass
• Ultrasound was routinely used
• A safety-tipped needle/catheter was used
• Fluid was removed by manual hand pumping (not vacuum bottles)
• CXR only done post-procedure if patients were symptomatic
• No blood products were given for low platelets or thrombocytopenia

Bottom line: Use your ultrasound to direct your tap and dont take out more than 1500 mL routinely

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Aside from sodium chloride and sodium bicarbonate, several commonly used emergency department medications (namely IV antibiotics) contain a significant amount of sodium. In patients with heart failure or other conditions requiring sodium restriction, judicious use should be considered.

Notes:

• Available references all quote slightly differing sodum contents. Therefore, the daily totals are approximate, but within 100 mg of the various references.
• To convert mg to mEq or mmoL, divide by 23.

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There are some studies that have shown that NSTEMI patients have done worse when administered opioids. Most studies were not well controled and the exact mechanism was not clear. This study adds a biological mechanism to these fidnings.

Hobl et al. showed clopidogre concentrations delayt peak yhours, have overall decrease AUC and actually decrease active metabolites when morphine is administered IV. Morphine may not be the right choice in any ACS that receives clopidogrel.

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A Lancet Commission on Global Surgery has just published a 56 page article about the need to improve access to surgery and anesthesia care.  Its five key messages are:

• 5 billion people lack access to safe, affordable surgical and anaesthesia care when needed
• 143 million additional surgical procedures are needed each year to save lives and prevent disability
• 33 million individuals face catastrophic health expenditure due to payment for surgery and anaesthesia each year
• Investment in surgical and anaesthesia services is affordable, saves lives, and promotes economic growth
• Surgery is an indivisible, indispensable part of health care

The need for high quality acute care, both for urgencies and emergencies, is clearly an important component of providing “universal access to safe, affordable surgical and anaesthesia care”- the vision of the Commission.

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SIRS and Severe Sepsis Screening

• Sepsis remains one of the most common critical illnesses managed by emergency medicine and critical care physicians.
• Many EDs and ICUs have screening protocols for early detection of the patient with sepsis. Most protocols use the systemic inflammatory response syndrome (SIRS) as a central component of early identification.
• A recent study stresses caution when simply using the SIRS criteria to screen for severe sepsis:
  • Retrospective review of the ANZICS Adult Database
  • Divided patients into SIRS-positive ( 2 SIRS criteria with at least 1 organ failure) and SIRS-negative ( < 2 SIRS criteria with at least 1 organ failure)
  • 109,663 patients
  • 12% of patients diagnosed with severe sepsis or at least 1 organ failure had < 2 SIRS criteria at admission.
  • Mortality for the SIRS-negative cohort remained relatively high at 16.1%
• Take Home Point
  • Using the SIRS criteria to screen patients for severe sepsis will miss 1 out of every 8 patients with infection and organ dysfunction.

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Question

70 year-old female presents from a nursing home with fever and abdominal pain. A right upper quadrant ultrasound is shown, what's the diagnosis?

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In cases of suspected spinal infection, the sensitivity of an elevated WBC count (35-61%), ESR (76-95%) and CRP (82-98%) may help guide further evaluation or consideration of other entities.

Incorporation of ESR/CRP into an ED decision guideline may help differentiate those patients in whom MRI may be performed on a nonemergent basis.

An elevated ESR (>20 mm/hour) also has a role in the diagnostic evaluation of occult malignancy (sensitivity 78%, specificity 67%).

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Some medical issues arise in patients with brain tumors:

// Steroids are used to decrease vasogenic edema, especially preop or during radiation therapy. Patients are ideally gradually weaned off steroids. Dexamethasone is most commonly used. 1-2% of patients are at risk for adrenal suppression.

// Infections: Post-op wound infections can be delayed up to months, especially in patients on steroids.

// Antiepileptics: Although technically not recommended in patients with brain tumors who have not had seizures (American Academy of Neurology 2010), many surgeons continue to prescribe antiepileptics preoperatively and then discontinue them by 1 month postop if the patients remain seizure-free. Levetiracetam is emerging as the drug of choice due to favorable side effect profile.

// Thromboembolism: Brain tumors are considered very high risk for venous thromboembolism. Low-molecular-weight heparin is the treatment of choice, with warfarin being an acceptable substitute.

// Arterial thrombosis and ischemic stroke: Risk is increased with certain medications, and thrombolysis is contraindicated.

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Updates in the Management of Large Hemispheric Infarction

Large hemispheric infarctions (LHI) are estimated to occur in 2-8% of all hospitalized ischemic strokes and 10 15% of all MCA territory infarcts. LHI carry high rates of morbidity and mortality, in fact, if left untreated associated cerebral edema can rapidly progress to transtentorial herniation and death in 40 80% of patients.

Recognized risk factors for progressive cerebral edema include:

• NIH stroke scale > 20 in dominant hemispheric infarct
• NIH stroke scale > 15 in nondominant hemispheric infarct
• Rapid decline in level of consciousness (LOC) indicates effect on contralateral hemisphere (due to ipsilateral swelling)

Evidence based medical strategies for LHI include:

• Positioning: Elevation of the head of the bed (HOB) > 30 degrees
• Glucose control: 140 180 mg/dL (hyperglycemia associated with increased ICP and progression to hemorrhagic conversion)
• Blood pressure control: 15% reduction MAP over 24 hours if BP exceeds 220/120 (likely best accomplished with nicardipine infusion to avoid overcorrection)
• Osmotic therapy: In the deteriorating patient, consider hypertonic saline (23%) with goal Na of 160 mEq/L or mannitol with goal plasma osmolality of 320 mOsm/kg.
• Adjunctive therapies: Prevent fever and hypercapnea

Prophylactic hemicraniectomy

• Consider early neurosurgical consultation for patients with LHI as newer evidence suggests prophylactic hemicraniectomy may improve survival if performed within 24 48 hours.

Bottom Line: Early recognition of large hemispheric stroke is critical as it is associated with a high rate of morbidity and mortality. Aggressive medical management and early neurosurgical involvement may improve outcomes.

References

1. Zha AM, Sari M, Torbey MT. Recommendations for management of large hemispheric infarction. Curr Opin Crit Care. 2015;21(2):91-8.

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You see the following on a parasternal long-axis view; what's the diagnosis and what coronary distribution is involved?

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Cardiac Sarcoidosis

- Cardiac Sarcoidosis (CS) is reported to involve ~2-5% of patients with systemic sarcoidosis. An increasing proportion of patients are presenting with isolated CS.

- Isolated CS is associated with a higher female predominance; severe LV involvement, heart failure, and poor prognosis.

- Manifestations range from symptomatic conduction disturbances, dysrhythmias, progressive heart failure, and silent myocardial granulomas - leading to sudden cardiac death.

- CS is a serious condition with a quoted 5-year survival ~60-75%.

- Corticosteroid therapy is considered cornerstone in management, but evidence is largely observational and no randomized trials have been performed to date.

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Is acetaminophen good for pain control in patients with Osteoarthritic of the Knee or Hip or Low Back Pain?  Most of my patients request narcotics, but conventional teaching is that we should try to start with Acetaminophen or NSAIDs.

This recent study, http://www.bmj.com/content/350/bmj.h1225, published in the BMJ analyzed 13 studies looking at over 5400 patients.  In the end, they found that acetaminophen did not appear to improve pain, disability or the patient’s quality of life in patients with back pain. Also, there was a small improvement in pain and disability in those with hip and knee pain, but it was not deemed clinically significant.

Even worse, patients taking acetaminophen had a 4x greater chance of having abnormal liver function tests.

This meta-analysis really questions whether Acetaminophen should be first line therapy in patients with osteoarthritis of the knees or hips, or in those with low back pain.  For now I will stick with a course of a NSAID.  Especially with the risk of unintentional overdose if they are taking other over the counter medicaitons that might also contain acetaminophen.

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Approximately ¼ of lumbar punctures (LP) are traumatic or unsuccessful in infants.  What is the implication of this?

A retrospective cross sectional study over a 10 year period at Boston Children’s Hospital looked at infants aged 28 to 60 days who had blood cultures sent from the Emergency Department and who had LPs performed. The ED clinicians at this facility routinely follow the “Boston Criteria” to identify infants at low risk for spontaneous bacterial infection (SBI).  Traumatic LPs were defined as CSF red cell count greater than or equal to 10x10^9 cells/L while an unsuccessful LP was defined as one where no CSF was available for cell counts.  A small portion of the unsuccessful LPs did not have CSF cultures sent.

173 infants had traumatic or unsuccessful LPs.  The SBI rate did not differ between the normal LP and the traumatic and unsuccessful LP infants.  Median hospital charges were higher in the traumatic or unsuccessful LPs compared to the normal LP group ($ 5117 US dollars versus $ 2083 US dollars).

Bottom Line:  Traumatic or unsuccessful LPs lead to higher hospital charges.

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