Mythbusting, Radiology

POCUS gel – hot or not?

“Wow thats cold!”

It’s a common statement after applying the probe to a patient, and wouldn’t you love to know the answer to the age old question, “Does gel temperature matter for patient satisfaction?”… While we have some data suggesting improved patient satisfaction scores with POCUS, but could those scores be better if the gel was warmed? Or perhaps would all the improvement in satisfaction scores be lost with cool gel?

This group performed bedside ultrasound using heated gel (102F) or room-temperature gel (82.3F – quite the warm department!).  The investigators even went so far as to trying to blind those performing the study with a heat-resistant glove (!) – and even validated gel temperature through weekly quality assurance measurements throughout the study period.  The investigators informed all patients that the study entailed investigation into various measures to improve patient satisfaction with POCUS, but did not inform them of their specific focus on gel temperature.  After POCUS was performed, patients completed the following survey: “How satisfied are you with the experience of having a bedside ultrasound today?” (on a 100-mm visual analogue scale (VAS) for satisfaction), as well as, “Are you satisfied with the care you received today in the emergency department (yes or no), as well as “How professional was the provider who performed your bedside ultrasound?” (A Likert scale spanning 1-5)

All in all, 59 patients underwent randomization to POCUS with room-temperature gel and 61 underwent randomization to heated gel.

In the end, heated gel made no difference for any of the three questions posed to patients. While I think those of us utilizing warm gel were probably making space in the blanket warmer, it’s nice to know that this intervention, while nice, does not make much of a difference, and a “special” warmer specific for gel in your department is probably unnecessary.

Improving Outcomes, Improving Throughput, Radiology

Parting the SEA with the almighty H&P (& rapid MRI).

Necessity is the mother of invention, and sometimes, necessity comes in the form of hospital administration after a bad outcome. The authors of this paper, essentially developed a rapid MRI protocol for suspected spinal epidural abscess after “several cases of SEA associated with delayed diagnoses and poor outcomes prompted the chairs of the departments of emergency medicine, neurosciences, medicine, and radiology, and members of the Division of Healthcare Quality, to develop a multidisciplinary, clinical decision support tool and imaging protocol with the goal of facilitating early recognition of SEA.”

Wow. Talk about moving mountains. If you’re department is anything like mine, it takes hours to agree on where we’re getting take out from; I cant imagine adding in 4 entire departments into the lunch-ordering mix, let alone all agree on a protocol.

They took a relatively simple approach – if you have new or worsening back/neck pain AND a history of spinal abscess or current/recent (6 months) bacteremia, straight to MRI. I think the recent bacteremia often gets lost in the work up, so I appreciate that they put this front and center. If there is no recent spinal infection or recent/current bacteremia, They looked at risk factors- and I’ll make this simple and break it into 2 categories: people putting things where they dont belong (IVDA, vascular catheters, spinal procedures/injections) and the recurrently ill: ED visit or antimicrobial treatment within 30 days or an infectious process elsewhere. If yes, head to MRI.

I’m torn a bit on this- while I want to applaud the authors for not dwelling on a variety of risk factors that only a small portion of the population has – alcoholism, HIV, severe COPD, the undomiciled, HepC, oncology patients, transplant patients, etc; to say that this group is pretty much captured in the recent ED visit category probably misses a fair amount of patients on the first go-round. And here is the problem of trying to find a needle in the haystack – its hard to increase sensitivity and specificity without causing a delay at some other portion of the food chain – every stat MRI for so many additional back pain patients pushes out another patient and potentially extends at least 1 other patients length of stay.


Despite an increase from 56 MRI’s in the 7 months pre-intervention to 147 in the 7 months post-intervention, yield for a positive MRI (defined solely as SEA and not vertebral osteomyelitis or infectious discitis), went from 16.1% to 17.7%.

On first glance, that’s not a lot of improvement in yield, but they screened 3 times as many patients without losing yield! This is rather impressive. However, they tripled their ED MRI rate, and, even though they drastically cut turn around times from 8.6 hours to 4.4 hours from time of MRI order to radiology report, thats still well over 4 hours for patients with back pain in a highly optimized system. And while yes, they missed fewer SEAs, they probably still have a good percentage that they missed on first visit – the various forms of immunocompromised – the severe COPDer on repeated steroid prescriptions, the HepC patient, the elderly – these are likely missed on the first go round.

I think this is a great step towards creating a policy towards SEA workup. It needs some refinement, but is the best I’ve seen yet. It poses some issues for smaller facilities that do not have 24/7 MRI capabilities, as well as for consultants (neurology essentially becoming a house officer for ID and neurosurgery), and poses a big time crunch for the ED (again, neurology took control of these cases once the decision to MRI was performed, which the hospitalists must be thankful for!). In the end, there is no such thing as zero miss, but Baystate, with this study, demonstrates that, at least for one day, the H&P is not dead.


If you build it, will they come (back)?

This is a review of 2.5 years worth of lower back pain.  Basically, every single patient with an ICD-9 code had their chart reviewed to ask the question, “If you got an MRI in the ED, are you less likely to return?”

They specifically did not look at yield, rather, just whether or not patients initially thought to have plain, old back pain came back.
The answer, contrary to those of us who think more is more, is no.   Repeat visits for those that had an MRI was 4.3%, repeat visits for those without an MRI at initial visit- 4.6%
However, it does give you some insight into who returns – they were more likely male (5.9% vs 2.8%) – further demonstrating that males are in fact the weaker sex.  They were more likely English speaking (4.9% vs 2.1%) and, speaking of which, non-English speakers were less likely to have an MRI (12.2% vs 7.4%), and self-pay patients were also less likely to have an MRI (9.8% vs 5.1%).   Its unclear if this further demonstrates a touch of bias on the provider side, if English-speaking patients speak up more about wanting diagnostics, or if non-English speakers just go to another hospital since this was a single center study.
As a secondary measure, they also looked at disposition for these patients.  Only 16% were discharged after MRI (vs 82% of those without MRI), 74% of those MRI’ed were placed in observation status (vs 11% of those not), 9% of those MRI’ed were admitted vs 3%, and 4% of those not MRI’ed left prior to completing treatment. Now, for some fancy math.
of the 797 patients who received an MRI over this time period, if only 11% were placed in obs status (rather than 74%), that is only 88 patients rather than 591 patients placed in obs status. that’s 503 patients with an unnecessarily padded bill. At $35.8013 per RVU, were talking tens of thousands of dollars billed that’s wasted.
Or, to put it another way, if you are in an area with a good payor mix, why not just obs & MRI them all?
Cardiology, Cardiology, Critical Care, Improving Outcomes, Improving Throughput, Mythbusting, Pulmonary, Radiology, Radiology

Probing the dyspneic patient.

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.

Improving Throughput, Mythbusting, Pediatrics

Inching closer to discharging an ICH from the ED?

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?

Improving Throughput, Mythbusting, Radiology, Radiology

Whaddaya Mean You Can’t Learn POCUS?

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.

Survey says?

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.

Improving Outcomes, Improving Throughput, Mythbusting, Pediatrics, Pediatrics, Pediatrics

SCI still rare in kids.

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 films 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.