Wednesday, January 23, 2013

Speed Bumps

Modern science, as they say, advances at warp speed.  This article from the British Journal of Medicine is emblematic of the phenomenon.  Researchers in the UK, using sophisticated surveys, were able to identify a heretofore unacknowledged clinical indicator of acute appendicitis:  the Speed Bump Sign. 


The analysis included 64 participants who had travelled over speed bumps on their journey to hospital. Of these, 34 had a confirmed histological diagnosis of appendicitis, 33 of whom reported increased pain over speed bumps. The sensitivity was 97% (95% confidence interval 85% to 100%), and the specificity was 30% (15% to 49%). The positive predictive value was 61% (47% to 74%), and the negative predictive value was 90% (56% to 100%). The likelihood ratios were 1.4 (1.1 to 1.8) for a positive test result and 0.1 (0.0 to 0.7) for a negative result. Speed bumps had a better sensitivity and negative likelihood ratio than did other clinical features assessed, including migration of pain and rebound tenderness.


Presence of pain while travelling over speed bumps was associated with an increased likelihood of acute appendicitis. As a diagnostic variable, it compared favourably with other features commonly used in clinical assessment. Asking about speed bumps may contribute to clinical assessment and could be useful in telephone assessment of patients.

This is earth shattering research.  Nobel 2013 is not out of the realm of possibility.  If Ashdown, D'Souza et al are smart, they are, as we speak, putting together a randomized controlled trial comparing the positive predictive value of speed bumps vs potholes.  Or perhaps then extracting data from the cohort populations in order to identify correlative effects of transportation modes, i.e. double decker bus vs London Underground vs driving from home in a Peugoet.

The clinical applicability is obvious.  I can just imagine the groggy, grumpy general surgeon on call talking with the bada-bing hot shot Bro ER guy at 3am about a potential appy.

Surg-  Yeah?  You called me.
ER- Oh yeah, sorry to make you wait.  I was with another patient.  Anyway.  Sounds pretty classic.  22 year old male.  Pain started umbilicus, migrated RLQ.  Pretty tender RLQ with rebound, guarding.  WBC elevated to 15....
Surg- What about speed bumps?
ER-  I'm sorry?
ER- Hey dude.  Take it easy.  I have no idea what you're talking about...
Surg-  Of course you don't.  (Long sigh, audible on phone). You call me at three in the morning about an appy?  And you have no idea how many speed bumps the guy drove over on his way in to the hospital?  Typical ER.....Admit him.  I'll see him in  afew hours.  (Line goes dead)

The ineluctable march of progress; surgery will never be the same.


Anonymous said...

Fabulous info! Just learning more new stuff every day - so exciting.

-SCRN :)

ChrisF said...

This horseshit got published because it originates from the hallowed spires of the University of Oxford.
And they are cleverer than you and me, you know;-)