Answer: VizD Challenge Week of 5/21/2007

*NY Emergency Medicine Exclusive*

Congratulations to Jay - he is the first person to submit the correct answer to this week's VizD. Jay is the winner of $5

To view Jay's answer, click here.

View the VizD Question of the week.

This week, Dr Steve Menlove, Director of Emergency Ultrasound at Bellevue Hospital in New York City will discuss the answer to this weeks VizD

NYEM: What are the main features of this ultrasound?

SM: The most important finding is gas in the anterior wall of the GB. Sonographically, gas bubbles are hyperechoic, cast “dirty shadows” (as opposed to the “clean shadows” cast by stones) and create ring-down artifact – all of which are seen in this image. There appears to be some pericholecystic fluid on this image, but it’s not very clear. Less importantly, the GB is distended (greater than 4cm in transverse diameter).

NYEM: What clinical entity is this ultrasound typically associated with?

SM: Emphysematous cholecystitis.

NYEM: Can this be mistaken for other clinical conditions?

SM: There is nothing else that really looks like this image, but for the sake of discussion I’ll mention a few things: Air bubbles in the duodenum (recall that the “C-loop” of the duodenum abuts the GB) can be mistaken either for gallstones or for air in the GB wall. A porcelain GB has a calcified wall, which shadows (although the shadows should be cleaner and would not create ring-down like gas does.) There is a common normal variant called adenomyomatosis in which the wall is thick and contains cholesterol crystals which are bright reflectors and cast short (about 1cm) comet-tails. A GB which is chock-full of stones and has little surrounding bile creates the ultrasound sign called “Wall-Echo-Shadow” – a hyperechoic line (GB wall), then another hyperechoic line (the top layer of stones) then a shadow from the stones. The back wall of the GB would not be visible in this case.

NYEM: How is this condition treated?

SM: Emergency Cholecystectomy. IV antibiotics should be given as early as possible in the ED.

NYEM: How often have you seen this finding on ultrasound?

SM: Less than once a year.

NYEM: What is your favorite ultrasound textbook?

SM: I recommend A Practical Guide to Emergency Ultrasound by Karen S. Cosby and John L. Kendall to my residents. Emergency Ultrasound by Ma and Mateer is also excellent (a close second). There are many great US books which are not oriented to EP’s (my current favorite is Case Review: General and Vascular Ultrasound by William D. Middleton).

NYEM: If you were going to practice medicine in a remote village and could bring an ultrasound machine with only one probe, which probe would you bring?

SM: I guess a typical abdominal probe (curvilinear 3-5mHz).

NYEM: How did you become interested in ultrasound?

SM: I spent a month doing an ultrasound elective at an obstetrical hospital during my residency (back in 1992) and took to it. How great is it to be able to see into the body?

NYEM: What is the most challenging body part to ultrasound?

SM: Every body part can be tricky at times – especially so when patients are obese, gassy, or have had prior surgery. The neck of the gallbladder is often overlooked. Abnormal adnexae (e.g. TOA’s) take experience. The tail of the pancreas is often obscured by gas. Evaluating heart valves and regional wall motion abnormalities are beyond the scope of ED ultrasound imho. The danger inherent in all ED ultrasound is acting on faulty information. It is important to be cautious…

NYEM: Ultrasound use in EM is mainly used to examine the abdominal organs, heart, and pelvis; what is the next popular area you see us using it for?

SM: Ultrasound enthusiasts are coming up with new uses all the time (e.g. the eye and the lung have received attention recently). I think “rule out DVT” is a very useful indication (and not too difficult to learn.) Ultrasound for guiding procedures is also very useful.

NYEM: Thanks for your time

SM: My pleasure

VizD is a weekly contest of an interesting or pathognomonic image from emergency medicine. Its goal is to integrate learning into a fun and relaxed environment. All images are original and are posted with the consent of the patient. For more information please refer to the following link.

Answer: VizD Challenge Week of 5/7/2007

*NY Emergency Medicine Exclusive*

Congratulations to Helen - she is the first person to submit the correct answer to this week's VizD. Helen is the winner of $10

To view Helen's answer, click here

This week, Dr Lewis Nelson, Director of the Toxicology Fellowship at the New York City Poison Control Center will discuss the answer to this weeks VizD

NYEM: How frequent are diethylene glycol (DEG) poisonings?

LN: The DEG poisonings that make the news are the ones that occur in epidemics. It seems that every few years an epidemic DEG poisoning occurs somewhere in the world, and they are nearly always related to the use of DEG as a diluent/solvent for a medication. The first widely recognized epidemic occurred in the US in 1937 due to its use in an antibiotic formulation (sulfanilamide). The result of this event lead to the formation of the FDA. Epidemic poisonings have occurred recently in India, Bangladesh, Nigeria, and Haiti. In Haiti DEG was used as a diluent for a liquid acetaminophen preparation, and many (over 100) children developed renal failure and some died. Many of these kids were sent to the US for hemodialysis. This last poisoning event in Panama involved a sugarless cough preparation/expectorant that was widely used by diabetic patients, accounting for the different patient demographic. The DEG was sold as glycerine (glycerol), a sweet non-sugar that is used by diabetics, and is structurally very similar to DEG. Isolated cases of DEG in the US, while not common, poisoning occurs due to the use of DEG in industry and in automotive products (e.g., brake fluid).

NYEM: What makes diethylene glycol sweet in taste?

LN: Not only is DEG sweet, but so is ethylene glycol. DEG has even been purportedly used (illegally) in low quantities to sweeten wine. The reason for the sweet taste of these glycols (which are poly-ols) is likely related to the way these chemicals interact with our "sweet" taste receptors. Realize that sugars (such as glucose, which are receptors are likely supposed to sense) are also poly-ols, so this makes conceptual sense.

NYEM: It's interesting that the creation of the FDA was based on a poisonous elixir of diethylene glycol used in sulfanilamide, yet 70 years later we are still faced with this problem?

LN: This is likely due to the lack of sophistication and regulatory controls of these other nations. If you read the recent NY Times article on the path taken by the DEG to get from China to Panama it becomes clear that nowhere along the line, including at the end, did anyone verify that the contents of the drums labeled "glycerine" actually contained this compound. Never say never when it comes to things like this, but the US regulatory system is much tighter than it is in less developed nations.

NYEM: Have you recently seen a diethylene glycol poisoning in New York City?

LN: We have, though as mentioned above, it has been isolated in nature. Most cases have originated from the drinking of automotive or hydraulic fluid. In an odd case about two years ago, a young man was intentionally poisoned (in what I recall was a "joke") by the chemical used to make artificial fog, which contained DEG. Recently, a patient presented to her primary care physician with some vague complaints. On questioning she produced a bottle of Panamanian of "expectorante" purchased on a recent trip that that country. Although she did not have renal failure, her medication contained 8% DEG.

NYEM: If you were on a desert island and were poisoned with diethylene glycol but could only give yourself one of the following treatments – ethanol, fomepizol, or hemodialysis – which would it be?

LN: There is no know role for ethanol or fomepizole; in fact there is some weak suggestion that these may be harmful. The lack of insight stems from the fact that the parent compound, not the metabolite, may be the toxic component. This suggests that we need to be cautious making analogies between the various toxic alcohols. Hemodialysis is the treatment of choice as it clears both the parent compound (DEG) and any metabolites. However, if I was on a desert island I would go for the ethanol! (the thought of putting those catheters in my groin is pretty intimidating)

NYEM: Do you recommend a toxicology fellowship for Emergency Medicine Residents?

LN: Only for the motivated few, but this is a whole different discussion.

NYEM: What made you get so interested in toxicology?

LN: I understood pharmacology and physiology in med school.

NYEM: Do you have a favorite historical toxicologist?

LN: Lewis Goldfrank, although he may take offense to being labeled as historically important.

NYEM: How many editions are there of Goldfrank's Toxicology?

LN: Edition 8 is out, working on 9 already (only 4 years to go)

NYEM Are you working on any other books?

LN: Always! I, along with another like minded colleague and an ethnobotanist at the New York Botanical Garden, recently published a book on the medical aspects of poisonous plants. Its called the "Handbook of Poisonous and Injurious Plants", it has great pictures. I may have another book or two up my sleeve.

NYEM: Thank you Dr Nelson

LN: Anytime!

VizD is a weekly contest of an interesting or pathognomonic image from emergency medicine. Its goal is to integrate learning into a fun and relaxed environment. All images are original and are posted with the consent of the patient. For more information please refer to the following link.