Paucis Verbis: Head CT clinical decision rules in trauma

The ideal clinical decision tool has a sensitivity and specificity of 100%.

You need a high sensitivity to be sure that your negative result indeed predicts a true negative. That means if your clinical decision tool suggests that you don’t need to get a head CT, then your head CT would have been normal.

On the flip side, this realistically means there is a low-moderate specificity. That means a clinical decision tool with at least 1 positive criterion does not always mean that there will be an abnormal finding on head CT.

There are 3 major clinical decision rules that I’ve heard tossed around in the literature:

Canadian CT Head Rules (CCHR)
New Orleans Criteria (NOC)
National Emergency X-Radiography Utilization Study (NEXUS)-II

There is no perfect tool.

Take a look at these decision rules and their inclusion criteria.

The CCHR included patients with GCS 13-15. The NOC initially enrolled only patients with a GCS of 15.
All factor in age (≥65 years for CCHR and NEXUS-II; ≥60 years for NOC).
Interestingly only the CCHR, for better or worse, take into account mechanism of injury. I’m not sure I would obtain a head CT on a pedestrian with a graze wound on the foot from a slow-moving vehicle.

Which do you use? I use a combination of all 3 and my clinical gestalt.

PV Card: Head CT in Trauma – Clinical Decision Tools

Go to ALiEM (PV) Cards for more resources.

By Michelle Lin, MD|2021-10-15T10:59:57-07:00May 13, 2011|ALiEM Cards, Radiology, Trauma|

Videos: The EM Eye Exam

Thanks to Dr. David Duong and Dr. Najm Haqu (UCSF) for letting me cross-post their amazing instructional video on the “EM Eye Exam”. These videos were made for the purpose of teaching senior medical students on their UCSF-SFGH EM clerkship. I thought it’d be great to share these tutorials, since the eye exam is typically a daunting task for many medical students (and residents).

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By Michelle Lin, MD|2019-01-28T22:49:24-08:00May 12, 2011|Ophthalmology|

Tricks of the Trade: Ultrasound workshop setup

Have you ever been to an ultrasound workshop where each small group of attendees huddles around the small ultrasound display? Personally I think the 3 people closest to the display really see the images well. This tends to exclude the other participants.

Last week, I hosted (my first!) ultrasound workshop for the UCSF Alumni CME Conference where I showed peri-retired UCSF alumni from various specialties about the future of bedside ultrasonography. I equated it to the 21st century stethoscope. Thanks to my star team of ultrasonographers: Dr. Asaravala, Flores, Miss, Lenaghan, and Wilson.

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By Michelle Lin, MD|2016-11-11T18:54:22-08:00May 11, 2011|Tricks of the Trade, Ultrasound|

Paucis Verbis: Brugada syndrome

You always hear about it when working up syncope and sudden cardiac arrest in young patients, but it’s so easy to forget what it looks like on ECG. We so rarely see it… or DO we?!

This Paucis Verbis card on Brugada Syndrome is to help emblazon these ECG tracings in our mind, so that we don’t miss the subtle findings which place a patient at risk for sudden cardiac death. Pay special attention to Type 1, which is most specific for Brugada Syndrome.

PV Card: Brugada Syndrome

* Update 8/2/18: Only Type 1 and Type 2 are recognized for Brugada syndrome. The type 3 pattern is likely a normal variant.

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Adapted from [1]
Go to ALiEM (PV) Cards for more resources.

Reference

Antzelevitch C. Brugada Syndrome: Report of the Second Consensus Conference: Endorsed by the Heart Rhythm Society and the European Heart Rhythm Association. Circulation. 2005;111(5):659-670. doi:10.1161/01.cir.0000152479.54298.51

By Michelle Lin, MD|2021-10-15T11:04:55-07:00May 6, 2011|ALiEM Cards, Cardiovascular, ECG|

Trick of the Trade: Temperomandibular (TMJ) dislocation

Mandible, or TMJ, dislocations occur when the patient excessively opens the mouth, such as in a yawn. They are typically bilateral and are difficult to relocate because of masseter and medial pterygoid muscle spasm. You can relocate the condyles back into the TMJ space with gentle but firm intraoral pressure inferiorly and posteriorly. Often it requires some sedation to help relax the muscles of mastication.

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By Michelle Lin, MD|2019-01-28T22:49:39-08:00May 4, 2011|ENT, Tricks of the Trade|

Paucis Verbis: Asthma classification

Emergency physicians have the opportunity to educate patients and prescribe chronic inhaled corticosteroids to patients who should be on these medications chronically. Patients may be more receptive to education and advice given immediately after an asthma exacerbation, managed in the ED. Using the National Institute of Health/ National Asthma Education and Prevention Program classification system, physicians can quickly determine if the patient is a candidate for inhaled corticosteroids and initiate therapy accordingly.

PV Card: Asthma Classification system

In short, patients can be classified into one of 4 classes: intermittent, mild persistent, moderate persistent, and severe persistent asthma. Patients in these classes should receive either Step 1, 2, 3, or 4/5 medications, respectively. I remember that patient using daily short-acting beta agonists (SABA) belong to the moderate persistent asthma category.

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Go to ALiEM (PV) Cards for more resources.

By Michelle Lin, MD|2021-10-15T11:08:17-07:00Apr 29, 2011|ALiEM Cards, Pulmonary|

Paucis Verbis: Dental infections

To follow up with the wildly popular Paucis Verbis card made by Dr. Hans Rosenberg (University of Ottawa), here is his card on Dental Infections. This card summarizes common dental infection complaints (like the periapical abscess seen to the right) that we see in the Emergency Department.

PV Card: Dental Infections

Adapted from [1]
Go to ALiEM (PV) Cards for more resources.

Reference

Nguyen D, Martin J. Common dental infections in the primary care setting. Am Fam Physician. 2008;77(6):797-802. [PubMed]

By Michelle Lin, MD|2021-10-15T11:10:29-07:00Apr 22, 2011|ALiEM Cards, Dental|