Clinical Confidence Through Ultrasound

The Gist:  A small (n=74), yet promising study demonstrates the perceived decision-making utility of bedside ultrasonography (U/S) in managing septic patients using IVC diameter, IVC collapsibility index, and cardiac echo.  This may prove particularly useful for those of us (students) with limited clinical experience and confidence

The Ultrasound Podcast guys make U/S exciting and hip, yet I'm occasionally frustrated by the paucity of good data to sate the small scientific portion of my brain.  I often encounter ED physicians who don't believe that U/S really adds much to clinical practice.  If Drs. Mike Mallin and Matt Dawson can't convince them, perhaps journal articles can achieve that feat (although I remain suspect of anyone not excited about U/S after the 'name that 'stauche game' on the duo's echo episode). 

Results:

• Primary outcome achieved.  Treatment plan changed in 53% of the patients (n=39)
• A change in the volume resuscitation plan in 45% of patients (n=33).
• The decision to give pressors changed in 4 patients
• Physicians were more confident of their assessment of deranged vital signs after viewing the U/S.
• Sure, they're just treating numbers in this case, but this may point towards better understanding of the patient's physiological state (although what impact that makes on the patient is not addressed in this study).
• Only 10% of treating physicians found that the U/S data didn't contribute to patient management

The Good:

• Prospective
• Clinicians were initially blinded to the U/S results 
• Demonstrates bedside U/S is do-able by clinicians.  With minimal training, clinicians were nearly always able to obtain the necessary U/S data.
• U/S can actually change our ED management, adding to our clinical skill set and cushioning our certainty.

The Bad:

• Convenience sampling - no randomization
• Lack of generalizability - Most of the patients had sepsis or severe sepsis and very few had the scary elevated lactates, one tertiary facility
• Small cohort
• Power? No a priori calculation, so statistical significance for the primary outcome is not evaluated
• An average time of 138 minutes elapsed before the U/S was performed and an average of 160 minutes before the U/S was viewed by the clinician. 
• I think this may be missing some of the critical time in sepsis...perhaps the "early" in Early Goal-Directed Therapy
• Also, most shops I've been in obtain and interpret bedside U/S in real time
• Changes in interventions doesn't necessarily translate into a change in patient outcomes.

References:

Haydar S, Moore E, Higgins G, et al.  Effect of Bedside Ultrasonography on the Certainty of Physician Clinical Decisionmaking for Septic Patients in the Emergency Department.  Annals of Emergency Medicine Article in Press, 24 May 2012.  

I See Right Through You - Intro to EM Ultrasound

The Gist:  Within the Emergency Medicine (EM) realm, ultrasound (US) is gaining an incredible amount of momentum.  Once relegated solely to use in FAST (focused assessment with sonography for trauma) exams, obstetrics, and placement of vascular catheters, US use and its application are growing in EM.  Keep up by using US often, getting this application, and learning from these guys.

Radiology is boring so why should I care about US?  It takes too much time.  They're just going to get a CT anyways.

• Surprisingly, I occasionally let my "inner nerd" shine.  My discovery of EM US has highlighted this personality attribute, typically when discussing a patient's workup and my suggestion for an ultrasound is met with a scoff or a blank look.  I launch into a giddy medical student frenzy citing recent papers on the risks of radiation and efficiency of bedside US.  This is exciting stuff!  
• Both the medical and lay communities are exploring the burgeoning use of CT scans and the costs and risks associated therein, particularly in younger patients.  Thus, as a no-radiation study, US is gaining ground as a first-line imaging modality.  As a public health student, it's easy to get excited about the ways in which bedside US can help achieve better patient outcomes.
• Immediate gratification.  Medical students seemingly live for the pursuit of test results.  With US, one gets immediate feedback, readily allowing appropriate treatment and disposition.
• Bedside US can be quick.  Many challenge this point, but data are accumulating to suggest that ED length of stay (LOS) can actually decrease with bedside ultrasound by EM physicians. 
• Over a decade ago, a retrospective chart review demonstrated that patients with RUQ pain receiving a gallbladder US by EM residents had a significantly reduced LOS compared with those who had scans in radiology (1).
• Recently, a twitter update alerted me to a study at Sinai where ED US in appendicitis was associated with a decreased LOS  (2). 
• US for deep vein thrombosis by EM physicians also apparently decreases LOS (3)
• The CT scanner is often clogged, probably because between 1/8 and 1/14 patients presenting to the ED in the United States receives a CT scan (4).

But, US is so "operator dependent" and too "technical" for mere students.

• These excuses began this blog in the inaugural post, "Ultrasound for Dummies," a tidbit one might never know due to the tortuous and tangential nature of this blog.  In reality, increased emphasis on excellent US training in the EM curriculum is proving the opposite of these common refrains - EM physicians can perform adequate and timely US.  EBMedicine has an excellent summary of the evidence behind ED US.
• The key lies in hands-on practice...even more reason to get hooked early.
• US training and simulation is growing.  Many medical schools such as UC-Irvine are incorporating US throughout the four year medical school curriculum.  Check this out to see what the EDUS2 project is doing to promote cheap, effective US simulation.
• If the US is equivocal, you may still send the patient to the CT scanner (or perform other imaging/tests).  

Perhaps I'm now slightly intrigued by US...where do I start?

• The absolute first place to start is with the brainchild of Dr. Mike Mallin and Dr. Matt Dawson, Ultrasound Podcast where they "Make Horrible Doctors Decent and Good Doctors Great." (I wonder what they do to medical students?)
• This podcast is entertaining, thorough, and emphasizes the practical application of US in the ED.  Warning: (1) A few portions of the cardiac US lectures are dense and technical - bear through this and keep the podcasts on your phone for future reference (2) Don't listen to this podcast whilst running or driving (the video is key and this could be dangerous) (3) Listening to these podcasts on the elliptical in a public space may be detrimental to your image, as they are prone to make one burst into a fit of laughter.
• Although openly biased, the podcasts provide literature sources for the techniques presented and highlight aspects for future research.
• The free 1 Minute Ultrasound application for iPhone and Droid makes US accessible and quick in the ED.
• UC-Irvine has good, instructive video lectures downloadable via iTunes
• Many EM programs offer US electives for visiting medical students.  I can't comment on the quality of these yet, but I will in the next few months.
• Society of Academic Emergency Medicine (SAEM) has narrated lectures on a few techniques

Looking for a manual-style breakdown of various ultrasound procedures?

• SAEM  has Ultrasound Guides for common procedures in .pdf format and a links to other online resources.
• Ultrasound Guide for Emergency Physicians from ACEP is a little dry but one of the "go-to" resources in EM US training.

But, nobody around here ultrasounds...anything!

• Ultrasound each other.  The EM interest group at my medical school set up some time in the Vascular Sonography program's lab.  Students and instructors from that program were available to introduce us to the world of US.  
• Apparently, extra-firm tofu also works well for a delicious and inexpensive ultrasound simulation (reference #SAEM12).
• Ultrasound is an intellectual epidemic in EM.  However, if you just can't wait until your time in the ED, one can manage to find utility for ultrasound in nearly any medical field.
• For example, on a nephrology rotation, I somehow managed to introduce people to bedside IVC ultrasound and they got excited about doing it.  
• EDs have variable access to bedside US.  Tactfully advocate for improved patient care and outcomes by demonstrating the amazingness of US through the "1 Minute Ultrasound" application or by pandering to an outcome they're passionate about (ex: ED LOS).

Your charm and subtle enthusiasm for ultrasound piqued my interest in US...I want more! (Alternatively:  Supplement to an EM US elective)

• Add the SinaiEM.us blog to GoogleReader
• Case-based learner? Check out a plethora of neat case based videos.
• Ultrasoundvillage.com has an amazing image library, sort-able by organ system
• Search the web for EM US fellowship programs.  Many of these programs have extensive links and resources available, similar to the University of Arizona's list that provide excellent education.
• There are also excellent blog posts at takeokun.com
• The Stanford 25 take on bedside ultrasound, with various monotonic modules from USC. 
• Initiate dialogue with other specialists, students, and attendings on the utility and meaning of EM US.  An easy way to do this is to gift someone the "1 Minute Ultrasound" app...it's the right price for medical students.