Welcome to the 93rd edition of Research and Reviews in the Fastlane. R&R in the Fastlane is a free resource that harnesses the power of social media to allow some of the best and brightest emergency medicine and critical care clinicians from all over the world tell us what they think is worth reading from the published literature.
This edition contains 6 recommended reads. The R&R Editorial Team includes Jeremy Fried, Nudrat Rashid, Soren Rudolph, Anand Swaminathan and, of course, Chris Nickson. Find more R&R in the Fastlane reviews in the : Overview; Archives and Contributors
This Edition’s R&R Hall of Famer
Bair AE, Chima R. The Inaccuracy of Using Landmark Techniques for Cricothyroid Membrane Identification: A Comparison of Three Techniques. Acad Emerg Med 2015. PMID 26198864
- This randomized trial of Emergency Physicians use if various techniques to identify landmarks for cricothyrotomy showed that these techniques have limited sensitivity (46-62%), when ultrasound was used as the gold standard. The paper doesn’t speak to procedural success or patient outcomes but given the potential inadequacy of landmark identification, it seems prudent to use ultrasound to mark anatomy in an anticipated difficult airway, should time allow.
- This study of 50 volunteers suggests that three commonly taught methods for finding the cricothyroid membrane (general palpation, four-finger, skin crease) are relatively inaccurate, using ultrasonography as the gold standard. I conclude:1. The landmark techniques are inaccurate for finding the CTM *and that’s okay.* Make your best guess using general palpation and if you feel nothing, use four-finger or skin crease **and then make a long vertical incision.** Once you get through the skin you are very likely to be able to feel the CTM, and even if you still can’t at that point, that’s fine too, cut to air.2. If you have time to prepare (e.g. prior to RSI in a patient predicted to be very difficult laryngoscopy) put the ultrasound probe on the neck and mark the CTM.
- Recommended by Lauren Westafer, Reuben Strayer
Schechter MT, Sheps SB. Diagnostic testing revisited: pathways through uncertainty. Can Med Assoc J 1985;132(7):755-60. PMID: 3884119
- The authors in this review, describe 4 principles clinicians can use and teach to stop the epidemic of over testing which beleaguers healthcare. Did I mention this was published in 1985? The principles are
- In the diagnostic context, patients do not have a disease, only a probability of disease.
- Diagnostic tests are merely revisions of probability.
- Test interpretation should precede test ordering.
- In general, if the revisions in probabilities caused by a diagnostic test do not entail a change in subsequent management, use of the test should be reconsidered.
- Full of pearls and examples of how to apply these principles at the bedside, this article is a great read. Also, not to be missed, is the appendix with a MS-BASIC program to calculate post-test probabilities given a positive or negative test result.
- Recommended by Jeremy Fried
- Further information Diagnostic Decision Making in Emergency Medicine (Emergency Medicine Cases)
Capp R et al. Emergency Department With Sepsis and Progress to Septic Shock Between 4 and 48 Hours of Emergency Department Arrival. Crit Care Med. 2015; 43(5): 983-8. PMID: 25668750
- It would be great if we could predict which patients with sepsis will develop septic shock within a short period of time after admission to the hospital. This retrospective chart review attempts to identify factors from the patient’s Emergency Department course which may predict short term decompensation. Although the article has inherent flaws based on its design, it has important findings that can be used to improve patient care. In particular, it points out that non-persistent hypotension is strongly associated with short term decompensation (OR = 6.24)
- Recommended by Anand Swaminathan
Costantino G et al. Syncope risk stratification tools vs clinical judgment: an individual patient data meta-analysis. Am J Med 2014; 127(11): 1126. PMID: 24862309
- Although limited by it’s retrospective nature, this meta-analysis is an interesting contribution to the current state of knowledge on syncope patients presenting to the emergency department, and importantly, demonstrates that clinical judgement outperforms decision tools.The authors identified all prospective studies in which one of the many syncope tools could be derived. They then contacted the primary author of the initial studies to obtain the individual patient data. Six of the thirteen identified authors did so.
- The decision to admit or discharge the patient was used as a proxy for clinical judgement of high v low risk, and compared to the different decision tools. While there was no difference in specificity between any rule and clinical judgement (all low), the sensitivity of clinical judgement was significantly better than that of the decision tools. A well done article that reminds us there is an important role for clinical judgement in risk stratification of syncope patients.
- Recommended by Jeremy Fried
Perez MR et al. Sternal fracture in the age of pan-scan. Injury 2015; 46(7):1324-7. PMID: 25817167
- Not surprisingly, sternal fractures found only on CT aren’t associated with serious underlying injuries. This makes a lot of sense: first, the classic teaching that sternal fractures indicate badness refers to sternal fractures found based on exam or CXR, which are plausibly the worst of the worst. This paper is perhaps most interesting not for this specific finding but for what it represents: classic signs of badness likely don’t portend bad outcomes when found incidentally on advanced imaging.
- Recommended by Seth Trueger
Malbrain ML et al. Fluid overload, de-resuscitation, and outcomes in critically ill or injured patients: a systematic review with suggestions for clinical practice. Anaesthesiol Intensive Ther 2014; 46(5):361-80. PMID: 25432556
- If the intensive care literature is consistent about one thing, it is that there is nothing positive about positive fluid balance. This paper reviews the literature, offers up a host of relevant definitions – including one for ‘de-resuscitation’ – and suggests how ‘Late Goal Directed Fluid Removal’ might be done. Paul Marik is one of the authors so ‘iatrogenic salt water drowning’ gets a mention. Enjoy!
- Recommended by Chris Nickson