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Three Part Question

In [children with suspected intussusception], can [emergency physicians, using bedside ultrasound], [confirm or exclude the diagnosis of intussusception]?

Clinical Scenario

A 3-year-old boy comes in with intermittent bouts of severe abdominal pain. You are thinking of intussusception as the most likely diagnosis. It is night time and in your institution, the access to a formal ultrasound is limited at this time of day. You have heard of case reports of intussusception diagnosed by emergency physicians using bedside ultrasound. You wonder if there is any good evidence at diagnosing intussusceptions with this modality and you decide to search the available literature.

Search Strategy

There was no BestBET, CATS or Cochrane review found on the topic. The website clinicaltrials.org was searched for an ongoing trial: none was found.

Subsequently, EMBASE and MEDLINE were searched for relevant articles.

MEDLINE (through PubMed)

[(intussusception.mp) OR (exp intussusception/) OR (intestinal invagination.mp)] AND [(exp ultrasonography/) OR (ultraso$.mp) OR (echograph$.mp)] AND [(exp emergency medicine/) OR (emergenc$.mp)] AND [(exp diagnosis/)]

47 Articles were yielded; one was retained after abstract review

EMBASE [(exp intussusception/) OR (intestinal invagination.mp)] AND [(ultraso$.mp) OR (echograph$.mp)] AND [(emergenc$.mp)] AND [(diagnos$.mp)]

Search limited to English, French, humans, newborn, infant, preschool, school, child

Search Outcome

240 Articles were found but only one was retained after abstract review.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Riera et al. 2012 USA	82 children suspected of having ileo-colic intussusception (non-consecutive enrollment due to requirement of being recruited by one of the 6 emergency physicians trained to performed the US) All patients got bedside USS by one of the six trained EP (who had received a 1-h focused training session), then underwent a formal USS in the radiology department The results were then compared, the radiologist\\\'s USS being considered the gold standard	Observational study	Performance characteristics of bedside USS by paediatric EP (sensitivity, specificity, NPV and PPV)	Sensitivity 85% (54%-97%) Specificity 97% (89%-99%) Positive predictive value (PPV) 85% (54%-97% Negative predictive value (NPV) 97% (89%-99% LR+ 29 (95% CI 7.3 to 117) LR− 0.16 (95% CI 0.04 to 0.57)	Limited number of trained EP Small sample size resulting in large CI Non-consecutive convenience sample 52% of the US performed by the same EP EP previous experience with USS not precisely documented Cannot generalise results to physicians not previously trained in US Delays between the ED and the radiology USS may explain some of the FP results (self-resolving intussusception)
Zerzan et al, 2012, USA	99 Patients aged 3 months to 6 years with suspicion of intussusception Patients underwent bedside USS by one of the EP (who had received focused training) then underwent a formal USS in the radiology department The results were then compared; the radiologist\'s USS being considered the gold standard	Observational Study	Performance characteristics of bedside USS by paediatric EP	Sensitivity 89% (95% CI 0.05% to 0.99%) Specificity 98% (95% CI 0.91% to 0.99%) LR+ 40 (95% CI 10 to 160) LR− 0.11 (95% CI 0.02 to 0.72)κ value 0.825	Poor description of methodology Number of EP performing USS unclear Principal investigator\'s previous US training unknown, yet he provides the training session Small sample size resulting in large CI

Comment(s)

The included studies suggest that emergency physicians using bedside ultrasound could rule in children with suspicion of intussusception with a high specificity (97–98%). The sensitivities, however, were much lower (85–89% with wide CI), which seems clinically unacceptable when a diagnosis with such possible dismal consequences is suspected.

Both studies were based on relatively small size resulting in large CI making the final decision difficult.

Editor Comment

ED, emergency department; EP, emergency physician; LR, likelihood ratio; NPV, negative predictive value; PPV, positive predictive value; USS, ultrasound scan.

Clinical Bottom Line

ED bedside ultrasound could possibly be used to rule in intussusception in children for whom this diagnosis is suspected, with high specificity. However, its value to rule out intussusception has yet to be proved.

Further studies need to be conducted to confirm its utility as a diagnostic tool for suspected intussusception in children in the ED.

References

1. Riera A, Hsiao AL, Langhan ML, et al. Diagnosis of Intussusception by Physician Novice Sonographers in the Emergency Department Annals of Emergency Medicine Mar 14. [Epub ahead of print].
2. Zerzan J, Arroyo A, Dickman E, et al. Diagnosing intussusception by bedside ultrasonography in the pediatric Emergency Department. Abstracts of the 2012 Society for Academic Emergency Medicine (SAEM) Annual Meeting; 9–12 May 2012, Chicago Acad Emerg Med 2012;19(Suppl. 1):S1–426.