Evaluation of Hypoglycemia

Interpretation of labs drawn during the work up of hypoglycemia (72 hour fast or mixed meal test). 

From the Endocrine Society’s Clinical Guidelines on Evaluation and Mangement of Adult Hypoglycemic Disorders (pdf)

Dx of CHF in Dyspneic Pt: Need Echo?

53M PMH unknown 30 pack-year smoker presents with dyspnea to the ED. It's 2AM Saturday morning. The ED is PACKED with traumas, boarders, psychos… not to mention med students, residents & nurses strung out on caffeine or their stimulant of choice. Pt is desat'ing. Need to decide quick: Diuresis vs. Nebs? Diuresis won't help a dried out COPDer, and adrenergic nebs won't help a drowning CHFer. Echo Tech unavailable (this county hospital makes strategic budget cuts). 

How do you proceed?

NB: The H&P is very useful! Take the time to interview & examine the patient. Tell the med students & nurses to QUIET DOWN so you can hear that S3!

PV CHF LRs Collection:
Rivas CHF Dx Stats Collection:

NB2: Keep in mind that in CHF most findings are not conditionally independent  so usually cannot combine LRs for post-multiple-tests probabilities. Instead, rely on the most powerful finding you discover in that case (e.g. S3 to confirm dx or BNP less than 100 to exclude dx of CHF in dyspneic pt). Awesome free online course on Medical Decision Making btw. 

ROC Curves [BNP outperforms Echo EF%]



NB3: Here's the that shiny pearl you were waiting for…

CHF Dx Algorithm

NB4: This algorithm makes it look like H&P is useless. It's EXTREMELY useful (see LR tables above)! If you still can't make the diagnosis, obtain ECG & CXR. It should be the rare case when H&P+EKG+CXR is insufficient to make the diagnosis. In those scenarios, order BNP. Then, if BNP is indeterminate, perform bedside echo for Doppler MV Analysis for low Early/late (E/A) velocity ratio or short MV flow velocity Deceleration Time (DT) to cinch the diagnosis. Refer back to Rivas CHF Dx Stats. 

Explanation of MV E/A Ratio from Echo Doppler:

How to perform bedside Echo doppler MV assessment?
- Liz Turner from UC Irvine on FATE Exam: http://www.youtube.com/watch?v=9ybQ10m3uEY
- - That didn't quite answer my question, but came close. #FOAMed US gurus out there, help us out! Teach US!

Sources:
See losrivas EN Note. 

Ultrasound before MCTPA for PE dx

57M PMH COPD on home O2, smoker, CHF (baseline EF 30%), HTN, DM, obese (BMI 35), CKD (baseline Cr 1.6) presents to the ED with acute onset sharp, pleuritic chest pain at the right anterior chest radiating to the right axilla. Sinus tach on EKG with LVH & TWI that were present on prior EKGs. Tachypnea, O2 sat 90% on 4L NC. Afebrile. BP 127/89. A rhonchi & rales bilaterally. 3/6 holosystolic murmur throughout precordium. Obese abdomen. Bilateral LE edema pitting to the knees. Cr 2.2. WBC 12. CXR poor inspiration, bibasilar interstitial congestion, cardiomegaly, no pneumothorax, no fractures. It's a saturday night (skeleton crew - U/S tech isn't in, radiologist is tele-radiology, only one CT-tech in house with multiple emergent CTs in que). Pt has had multiple chest CTs in the past.

What's the risk of PE? Do you order a D-dimer? If you have a moderate to high suspicion for PE, do you go straight to CTPE? What about the likely delay in CT & the pt's acute on chronic renal failure? Another CT - are you worried about radiation exposure? Is there a way to spare this pt the CT?

A new study provides insight on a new diagnostic algorithm to to reduce the burden of CT for PE in the ED - if you've got the docs with the right skills! And again ALiEM provides PV Cards for easy access to relevant diagnostic & treatment rules and MDCalc helps too!

Dx of Meningitis - CT before LP

25M college student p/w worst headache of his life, fevers, chills, painful & stiff neck. PMH epilepsy. Off meds. Hasn't had a seizure in 10 years. No other significant past medical. Tachy, febrile, tachypnic, normal O2 sat. Positive nuchal rigidity on exam. Oriented, follows commands, no motor or gaze palsy. WBCs 14. Does he need a head CT before LP?

Click here for a JAMA Rational Clinical Exam piece on bedside dx of acute meningitis (can you trust Kernig and Brudzinski?), the study that established the CT before LP rules, and some useful cards from ALiEM's PV series to enhance your bedside recall of these rules.

tPA for the Management of Acute Ischemic Stroke - FreeOAM vs. {industry funded} Guidelines

In noon conference today, the presenting resident reviewed the AHA/ASA March 2013 guidelines on management of acute ischemic stroke. It was a good overview of the guidelines, but there wasn't a lot of room for debate on the evidence for and against tPA in this scenario. Luckily I've been privy to the tPA in acute stroke debate in the #FOAMed community.

Mini FOAMed Lit Review on the use of tPA for the management of acute ischemic stroke:

1. Emergency Med Lit of Note were out of the gate quick early this year to question the integrity of the ACEP guidelines on this topic.
2. theNNT convinced me with their thorough evidence based review. Their "red light" made it clear to me what the answer is on this topic. 
3. Recently LiTFL posted a two part series on this topic by Michelle Johnston. She left the final decision on the validity of tPA use for this indication to the reader, but her analysis is thorough and presents a strong case to exercise caution when considering tPA. 
4. Just this morning ALiEM's Todd Seigel posted a review focused primarily on the NINDS study, AHA, & ACEP guidelines. His post stands in contrast to the other FOAM contributions to this debate, and Graham Walker of theNNT & MDCalc was quick to point out this contrast. 

But can FOAMed stand up to 3 major organizations (AHA, ASA & ACEP) all arguing strongly for use of tPA in select patient groups?

Thankfully, there's at least one organization that has stood strong & reasonable. The AAEM have put out statements, commentaries, educational material, & letters all asking for an injection of evidence-based, calmly considered, carefully weighed thought, skepticism, debate, and further investigation on this topic. 

Despite some guidelines, it can at least be said, tPA for the management of acute ischemic stroke is not the standard of care.