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.