For undifferentiated dyspnea, how would you like to have an accurate diagnosis in 24 minutes?
I love this study.
Basically, for all dyspneic patients (not trauma related, and over age 18), 10 EP’s were given an H&P, vital signs, and an EKG, as well as access to a Chest X-Ray, Chest CT, cardiologist performed echo, and labs including an ABG.
These same 2,683 patients, in tandem, had point of care ultrasound testing (lung, IVC, echo). Here’s the catch – the ultrasonographers were only provided the H&P, vital signs, and EKG then asked to make a diagnosis. The treating provider was blinded to POCUS diagnosis.
These numbers for diagnostic accuracy of POCUS are astounding.
+LR for acute HF? 22 (-LR 0.12)
+LR for ACS? 105 !!!
+LR for pneumonia? 10.5 (-LR 0.13)
+LR for pleural effusion? 95 (-LR 0.23)
+LR for pericardial effusion? 325!!! (-LR 0.14)
+LR for COPD/asthma? 22 (-LR 0.14)
+LR for PE? 345!!!
+LR for pneumothorax? 4635!!! (-LR 0.12)
+LR for ARDS? 90
Yes, for certain things like pneumonia, the difference in p-values between tradition means and POCUS diagnosis was not significantly different, but what about volume status? I cant imagine blindly giving 30 cc/kg would benefit the patient with a plethoric IVC and pleural effusion. There is some elegance a play here.
Additionally, sure, ED diagnosis for ACS had a higher LR, but they also had a cardiologist performing and interpreting echos in the ED (a rather rare siting in a US ED I would imagine) – without much improvement in their -LR (0.53 vs 0.48). For PE, the -LR of POCUS was predictably mediocre if not outright bad (0.6), while the -LR for ED diagnosis of PE, with the benefit of chest CT, was -0.10.
Now look, I get that these EP’s were quite sono-savvy. They all had 2+ years of experience, over 80 hours of ultrasound lessons & training, with at least 150 lung and 150 ED echo’s under their belt. The diagnosis was made in 24 minutes with POCUS in comparison to 186 minutes for traditional means. And while most of us can not do a year+ ultrasound fellowship, and neither can we all be as savvy with the probe as these authors (or Matt, Mike, Jacob, Resa, Laleh, etc) – it does not mean we shouldnt try. You can still greatly increase your yield just by practicing. To boot, the cognitive offload you experience by saving yourself a few hours by (correctly!) knowing which direction you are heading with a patient is an immense boon to both your mental heath & your patients well being.
A few years ago, I was with an attending who was discharged a pediatric patient. Staff in general seemed hesitant, but this was a well-loved doc who’s reply was somewhere along the lines of, “this kid looks great! Do you know how many times my kids probably had a bleed and did fine? We over CT these young things! And if he has a bleed, what are they really going to do anyway besides charge a lot of money for no appreciable intervention?”
And with that, comes this retrospective single center study of 202 children 0-18 years of age with an acute CHI, an abnormal CT (defined as both nondepressed and depressed skull fractures, subdurals, epidurals, subarachnoids, intraparenchymal hemorrhage, and intraventricular hemorrhage), and a GCS 14 or higher.
Essentially, the question is, can these patients be safely treated in an obs unit?
Exclusions were multisystem trauma, nonaccidental trauma, prior neurosurgical conditions and coagulopaths were excluded as well. 86% of patients were 5 years of age and under, and only half of all patients presented to the ED in under 6 hours. My first reaction to this was “huh?” – but the authors go on to state the 73% of patients had a hematoma, 11% had LOC, 30% vomited, 28% had a change in behavior, etc… so I guess it makes sense that there was a delayed presentation since parents may have initially thought their child was alright, only to later to suspect something was afoot (or perhaps patients were transferred to their ED from outside facilities?).
Fun sidenote: 17% of patients had no exam findings, so I gotta ask – why were they scanned? To put it another way, much like the aforementioned doc had asked- how many kids have we discharged without a head CT with clinically insignificant ICH?
So what did the authors find? ZERO children were intubated, required neurosurgical intervention, PICU admission, or died. All were discharged within 72 hours, and 86% of patients with >1 CT finding were discharged within 24 hours! Surprisingly, this is actually somewhat consistent with prior studies.
Ultimately, before starting this at your institute, note that there are some subtleties in the data- like that 25% epidurals with a repeat CT (3 of 12) showed a larger bleed. But really, looking at the data on patients that were admitted, I have to ask – which of these *really* needed an admission? None had an intervention aside from continued analgesia / anti-emetics.
Of note, this hospitals EDOU had an admission rate of 3-4 % – wayyyyy below national average of 15-20% – so either they’re sending home a ton of kids from obs unnecessarily, their ED is placing way too many in obs, or the rest of us have it wrong. Which leads me to agree with the authors on the following:
“For those well-appearing children in whom CT abnormalities are visualized, an EDOU is still an appropriate place for these patients, or should early discharge with home observation also be considered?”
Will we see a time when certain types of head bleeds are treated like low risk chest pain – accelerated protocols and an abundance of EBM suggesting early discharge? Or arranging for telemedicine to circumvent many of these transfers to tertiary care centers?
After taking a few one day ultrasound courses, a common theme amongst classmates is something to the effect of, “well, I get it now, but what about next week when the instructor isn’t there to guide me?”
Admittedly, I have wondered about the same thing; and wondered about the retention of knowledge and ability to apply what you have learned at these 1-2 day crash courses.
So you think you cant learn ultrasound? Or that you can not retain it after a weekend course? Well, those damn whippersnappers from Oregon are putting the non-believers to shame.
Medicine interns at Oregon Health & Science University were taught point of care ultrasound 3 months into their first year, as one day of a 5 day medical “boot-camp.” The day-long program consisted of 15-20 minutes of didactic training, and was followed by a 40 minute hands on session. Learners were placed in groups of 2-3 individuals and taught one-hour modules consisting of: the basics (knobology, physics, etc), CLUE protocol, FAST exam, hydronephrosis eval, and aorta & neck anatomy. The 40 minute hands on portion was divided into 20 minutes for completing modules demonstrating pathology on SonoSim machines and 20 min for facilitator-led hands-on practice with volunteer models. (example- 20 didactic minutes learning FAST, 20 minutes on simulation, then 20 minutes on a real-live person!). This was followed by two optional 1 hour courses done within 6 months.
A 30 question multiple choice test was administered prior to the course to all 33 interns, testing image interpretation, image acquisition/optimization, and clinical applications of ultrasound. The test was re-administered 6 months later; there was a significant drop out rate (27%), and it was untracked as to whom took the optional one hour courses.
Mean pretest scores – 61%
Mean post-test scores- 85%
Mean 6 month post-test scores – 79%
Great news – We probably intuitively know & retain much more than we think, but just have to continue to pick up the probe to hone our craft. Bad news, I’m not certain that an ability to retain enough knowledge to improve a multiple choice test score is the same as making a correct clinical decision off of limited ultrasound skills. Admittedly, POCUS in the wrong hands can be a problem, and making clinical decisions based off limited ultrasound skills and knowledge is a difficult leap to take, but its one we invariably have to make in order to grow as a clinician.
So, yeah, don’t tell me you can’t learn ultrasound.
This paper demonstrates that once again, kids are quite durable.
The authors looked at 3701 patients under 19 years old evaluated for a cervical spine injury. Of the 44 patients with clinically significant cervical spine injury (CSI), 32 had plain films, none of which missed an injury.
32 out of 3701… or 0.86%
-There were ZERO patients under two years old with a CSI
Here is the caveat- one injury begets another. Of the 32 patients with CSI, ten (31%) had multiple lesions, with plain films not identifying all lesions in 4 patients. Given that, I think its fair to say CT (or admission for MRI) is warranted once an abnormality is found.
In summary, relevant cervical injuries in kids are rare (<1%), and plain films are a reasonable screening tool. CT is once again rarely needed, but beware since one injury seemingly begets another. I pretty much agree with the authors on this one,
“Our calculated 100 % sensitivity (90% on PECARN, finding 168 of 186 CSI) does come with a large confidence interval and it should be expected that plain film’s sensitivity for CSI is likely lower in clinical practice. However, the small risk of missed injuries from plain films must be balanced against the increased risk of malignant trans- formation from performing CT scans on all children with suspected CSI. “
So, what is really distracting? According to NEXUS (multiple links here), it is any long bone fracture, visceral injury requiring surgical consultation, lacs >10cm, degloving injuries, crush injuries, large burns, or anything causing functional impairment. Do these requirements dictate the need for head CT as well?
In the ongoing debate of EM vs Trauma for selective imaging, comes this paper. From April 2014 – September 2014, the authors looked at 330 patients with mild TBI (GCS 13 or higher), to determine if distracting injuries were truly an indication for head CT. Patients were excluded if 18 months or younger of age, over age 60, moderate/severe or progressive headache, 2 or more episodes of vomiting, +LOC, amnesia, seizure or antiepileptic use, intoxication, uncontrolled hypertension, anticoagulated, had a neurologic deficit, penetrating injury, or craniofacial deformity.
Of 184 patients with fractures & severe pain (90 lower limb, 56 upper limb, 36 thoracolumbar, and 2 pelvis fractures – note there were NO cervical fractures noted), 2 (1.1%) had brain edema on CT, while of the 146 patients with no fractures/dislocations and no/mild pain, only 1 (0.7%) had brain edema on CT. No patient in any group had any neurologic symptoms at 1 month or 3 month follow up.
For many of us, this confirms our practice. Please share with your pan-scanning colleagues.
What is your threshold for sensitivity of a test? If head CT missed 30% of bleeds, would we even do them? If UA’s missed 30% of UTI’s, would we even send them for anything other than culture? Would you feel comfortable making a decision based off a test that misses 30% of an infectious process that is common in your ED?
Here, 319 prospectively enrolled patients with suspected community acquired pneumonia were subjected to plain films and followed by Chest CT. CT revealed an infiltrate in a third of patients who did not have an infiltrate on chest film and excluded CAP in 29.8% of patients with an infiltrate on chest film. 6.9% of patients were hospitalized (rather than discharged), and 7.2% were discharged rather than admitted based off CT findings (22 vs 23 patients).
The authors suggest that changing the disposition on 14% of patients is worth the “just scan ’em” mentality, while I would argue that a better question would be, why waste everyone’s time when you could just pull out the ultrasound? (Not to mention you would have an answer faster, at ~95% sensitivity?)