R&R In The FASTLANE 168

Welcome to the 168th 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 5 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

Hutchinson PJ, et al. RESCUEicp Trial Collaborators. Trial of Decompressive Craniectomy for Traumatic Intracranial Hypertension. N Engl J Med 2016. PMID: 27602507

• The RESCUEicp trial looked at craniectomy as a last tier intervention in patients with severe TBI and refractory intracranial hypertension. Patients had to be between 10-65 years of age with a raised ICP of >25mmHg for 1-12 hours (different from the DECRA trial) despite stage I and II measures which were defined clearly. Patients that were not randomised to the decompressive craniectomy arm could have one later based on the discretion of the neurosurgeons or receive a barbiturate infusion.  The patients receiving a decompressive craniectomy had a lower mortality unfortunately they were more likely to be in a vegetative state with more disability compared to those randomised to medical care.
• Recommended by: Nudrat Rashid

Mitchell MA & Wartinger DD. Validation of a Functional Pyelocalyceal Renal Model for the Evaluation of Renal Calculi Passage While Riding a Roller Coaster. The Journal of the American Osteopathic Association 2016. PMID: 27669068

• I had to suggest this one in, because it contained some excellent quotes, such as “we thank Walt Disney World Resort’s Magic Kingdom theme park for allowing us to conduct this research on the park’s premises” and “seat assignment on the roller coaster was random and determined as a function of place in the waiting line.” Aside from the great quotes, I’m not sure the paper means much. They made a silicone model of a urinary collecting system containing 3 real kidney stones, and report that the stones had moved in location after the roller coaster was finished. This is clearly not ready for time prime, and I can’t imagine that people with back pain from renal colic are going to be excited to be getting on rickety old roller coasters. I will stick to suggesting sex for now.
• Recommended by: Justin Morgenstern

Wyman AJ, et al. The First-Time Seizure Emergency Department Electroencephalogram Study. Ann Emerg Med. 2016. PMID: 27745763

• First-time seizures can portend real epileptic disease. These investigators performed EEGs in the ED with a surprising number of true positives.
• Recommended by: Ryan Radecki

van Es J, et al. A simple decision rule including D-dimer to reduce the need for computed tomography scanning in patients with suspected pulmonary embolism. J Thromb Haemost 2015. PMID: 25990714

• This seemed to slip under the radar a little bit but this is a new decision tool for PE that aims for the sensitivity of Wells but improving the specificity. They do the usual regression on a data set to find a decision tool then apply it in a different validation set. The tricky bit is that someone had to “suspect PE” to get into any of these trials and i suspect that varies from place to place. Ultimately they get a tool that rules out those with dimer<500 and if it’s between 500 and a 1000 then you look for any of 3 things: signs of a DVT, haemoptyis and the dreaded “is PE most likely”. If any of these are ticked then get a CT. In their validation set this improved their “rule out without a CT” rate from 31% to 46% with a cost of increased false negatives from 0.5% to 1.9% (which is right around the “test threshold”). If other authors in different places can reproduce this (which they often can’t in these trials…) then this would be cool.
• Recommended by: Andy Neill

McDonald RJ, et al. Intravenous contrast material exposure is not an independent risk factor for dialysis or mortality. Radiology 2014. PMID: 25203000

• This paper won’t settle the ongoing debate about the real harms of IV contrast material, but it does hint that if CIN exists, it might be more of a laboratory finding than a true patient oriented condition. This is a large chart review looking at patients undergoing CT, and comparing those who received contrast material to those who didn’t. This is a relatively good topic for a chart review, as creatinine, dialysis, death, and CT scans are all objective events that are likely to be clearly recorded in the chart. They only included patients who had a Cr measured in the 25 hours before a CT and also in the period of 24-72 hours after the scan. They also excluded patients already on dialysis and those who were given multiple contrast doses. Ultimately they ended up with 21,346 patients who they matched 1:1 based on a propensity score so they had 2 groups: contrast and no contrast. Overall, the rate of acute kidney injury was 5%. The rate was the same whether you received contrast or not (4.8% versus 5.1%, p=0.38). The incidence of emergent dialysis was the same in both groups, and extremely low (0.2% vs 0.3%). The 30 day mortality rates were also similar, at 8.0% and 8.2%. Although the propensity matching done here means the results could be flawed, it highlights the important issue that led us to think contrast is dangerous: older and sicker patients tend to need contrast CTs, and they are at a high risk of developing acute renal failure in the first few days of their illness, whether or not they get the contrast. The contrast is just an easy scapegoat. This trial is not enough to demand changes in policy from radiology, but I think it fits with the bulk of the literature.
• Recommended by: Justin Morgenstern