Mid-Level Providers

Mid-Level Providers

Who they are, what they do, and why they’re changing emergency medicine

How to make sense of the puzzle and improve your practice.

When Patients Lie

When Patients Lie

How to Spot Deception, What You Can Do, and Why it Matters

Accusing anyone of lying is serious business, but when that person is your patient, the stakes are even higher. 

Raves and Saves

Raves and Saves

Advanced Emergency Management at Mass Gatherings

EM is crucial at drug-fueled electronic dance festivals, like this month’s Electric Zoo in New York.  

Transfusion Confusion

Transfusion Confusion

Knowing the Real Risks of Blood Transfusion

This routine procedure bears real risks and should be handled accordingly.

The ABCs (and T) of Rural EM

The ABCs (and T) of Rural EM

Situational Awareness is Key

When you’re practicing in the middle of nowhere, planning out a timely patient transfer can be as critical as securing…

DNR Means Do Not Treat . . . and Other End-of-Life Care Myths

DNR Means Do Not Treat . . . and Other End-of-Life Care Myths

Debunking 5 Fallacies

Improve your EOL care and communicate more effectively.

Through the Looking Glass

Through the Looking Glass

Three Novel Use Cases for Google Glass in the ED

How might augmented reality change your practice?

Augmented ED

Augmented ED

The future of emergency medicine?

EPs in Rhode island overcome hurdles to trial Glass for telemedicine and consider other applications.

All About Metoclopramide (Reglan)

All About Metoclopramide (Reglan)

Know the risks

Reglan should be used with caution if patients have Parkinson’s disease or are on antipsychotics.

Physicians Won't Be Silenced

Physicians Won't Be Silenced

ACEP's Gag Order Rejected

EPM readers speak out against ACEP’s new ruling prohibiting incoming leaders from answering questions from non-ACEP publications.

Changemaker

Changemaker

How One EP Transformed Mental Health Admissions in Virginia

Debra Perina combined her experience as a coroner with her time leading an ED to challenge the establishment.

Get the Gear Off

Get the Gear Off

Removing the Helmet and Pads is Crucial to Treating Spinal Injuries from Football

Up to 25% of c-spine injuries from football collisions may be exacerbated by the poor removal of helmet and pads.

The War on Death

The War on Death

by Greg Henry, MD

The guns and butter debate is really over, I guess.

How Do I Know if I'm Being Paid Fairly?

How Do I Know if I'm Being Paid Fairly?

Trust is key

I get paid based on my productivity, but I don't trust that my company is paying me accurately.

The Stethoscope of the Future

The Stethoscope of the Future

Bedside Ultrasound

The applications of bedside ultrasound have gone well beyond scanning the gallbladder . . . to the lungs?

The Medical Malpractice Rundown: A State-by-State Report Card

The Medical Malpractice Rundown: A State-by-State Report Card

When it comes to medical liability laws and culture, where you live matters.

Find out how your state stacks up against the other 49.

Oxygen is a Drug— Act Accordingly

Oxygen is a Drug— Act Accordingly

Understanding the dangers of indiscriminate oxygenation in the ED setting

As with many things in medicine, dogma seems to overpower the evidence in this arena. 

Gag Order

Gag Order

New ruling prohibits would-be ACEP leaders from answering questions from non-ACEP publications.

Greg Henry seldom fails to deliver on a promise. But this time, it looks like it’s out of his control.

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It is the first shift of your senior year and your attending asks if you can assist the 3rd year medical student with a “knee tap.”  Of course, you reply with confidence and a hint of arrogance.  You then find the medical student, who is frantically looking up the procedure on his Palm Pilot, and assure him that no pimping will occur today.  Both of you sit down and you began to educate a future physician on the art of the arthocentesis. 
   
The purpose of performing arthrocentesis of the knee or any other joint is twofold: therapeutic procedure to drain large effusions, hemarthroses and/or instill steroids or anesthetics;  and to diagnose crystal arthropathies or septic arthritis.  Arthrocentesis is contraindicated in patients with cellulitis overlying the site of needle entry.  Suspected bacteremia is a relative contraindication.  The largest synovial cavity in the body resides within the knee joint.  The knee may be tapped 1cm medial or lateral to the superior third of the patella and is directed toward the intracondylar notch.
 
Prior to performing the procedure, explain the procedure to the patient including risks, benefits and obtain informed consent.  Obtain your equipment and position the patient supine with the knee extended or flexed 15-20 degrees.  Identify the landmarks and mark the entry site with a skin marking pen.  When performing an arthrocentesis, maintain sterile conditions as joint fluid is prone to infection if bacteria is introduced.  Cleanse the skin with povidone-iodine or chlorhexidine and use a sterile drape.  Anesthetize the entry site using a 25-gauge needle, placing a wheal of lidocaine and then anesthetize the deeper tissues.  It is important to intermittenly pull back on the plunger during this step to exclude intravascular placement.  Obtain a large syringe with an 18-gauge needle and direct the needle behind the patella.  Do not “walk” the needle along the inferior surface of the patella as this may damage the delicate articulate cartilage.  Remove as much fluid as possible. “Milking” the effusion by applying gentle compression to the suprapatellar region with the opposite hand may aid in removal.  Once the procedure is complete, remove the needle and apply a bandage.  Crystal analysis can occur with one drop of synovial fluid, while cell counts generally require about 1 mL o ffluid.
   
The collected synovial fluid is then sent for cell count and differential, gram staining, culture, and crystal analysis.  A cutoff of 2000 white blood cells per milliliter and 75 percent polymorphonuclear cells is used to differentiate between non-inflammatory (OA and trauma) and inflammatory conditions.  Cell count and differential count cannot reliably differentiate among inflammatory conditions.  Gram staining and culture provide the most definitive evidence of septic arthritis.  The sensitivity is much higher for nongonococcal infections (50-75% gram stain and 75-95% culture) than disseminated gonococcal disease (<10% and 10-50% , respectively).  Consider blood, urethral, rectal or oropharyngeal cultures if gonococcus is suspected.  The sensitivity of crystal analysis is 80-95% for gout and 65-80% for pseudogout.  Needle-shaped, negative-birefringent, monosodium urate crystals seen in gout and rhomboid-shaped, positive-birefringent, calcium pyrophosphate crystals seen in pseudogout are visualized under a polarizing light microscope.  The presence of crystals does not exclude septic arthritis, although a St. Luke’s-Roosevelt Hospital retrospective review of crystal-positive synovial fluid aspirates suggests concomitant septic arthritis is rare (1.5% prevalence).  
    
Potential complications include a “dry tap”, failure to aspirate synovial fluid.  Obesity, hypertrophy of the synovium, obstruction of the needle lumen or misdiagnosis of the knee effusion may result in a dry tap.  A different approach (lateral or medial) should be attempted.  Localized trauma, pain, reaccumulation of the effusion or iatrogenic infection are other potential complications.  Arthrocentesis of the knee is a relatively benign procedure if properly performed.          

To get the full article please go to http://pmid.us/16687707
 
 
 

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