Toxic Thursday: EKG changes in overdoses!

To follow-up on the digoxin toxicity POD from aggggggges ago, here's a sampling of some pathognomonic EKG changes in the setting of drug toxicity (this is NOT all-encompassing-- there's a lot more out there!) 1) Older woman with HTN comes in w/ dizziness. 2) Young disheveled guy, somnolent. 3) Old guy on blood thinner w/ HTN, new renal failure and weakness. ​

4) Old Asian man with cardiac and renal problems comes in vomiting (1st EKG from PMD's office, 2nd from MMC)

​

5) Old lady with vomiting syncopizes (First EKG progresses to second

​ ------------

Answers:

1) Long PR interval = AV nodal delay

= 1st degree Heart Block (may progress to complete heart block)

- Beta-blockade

- Calcium-channel blockade

- Digoxin

- Opioids, clonidine

2) Interventricular slowed conduction w/ long QRS, right axis deviation w/ R/S ration >0.7 in aVR

= Na-channel blockade

- TCA toxicity

- Anticholinergics

- Na-channel blockers like the "ides'

- Propanolol

- Anesthetics like bupivicaine

- Carbamazepine

3) Atrial tachycardia w/ AV block and PVCs (can also have PACs)

- digoxin! (classical finding)

​

4) Ventricular dysrhythmia w/ beat-to-beat alteration of QRS orientation

= Bidirectional Ventricular Tachycardia  (may also have multiple ectopic beats mixed in)

- digoxin! (pathognomonic finding)***

- also a few herb toxidromes (aconite)

​ 5) Long QT = prolongation of repolarization = risk of Torsades

- Non-toxicological risks: female, >60yo, genetics, structural heart dz/LV dysfunction

- Sympathicomimetics and:

​- Use the QT normogram (based on absolute QT) to predict risk of Torsades! (drugs that cause bradycardia are MORE likely to cause Torsades)

*** Just to summarize, the most common EKG presentations of digoxin toxicity are:

1) PACs/PVCs

2) Atrial tachycardia w/ AV block (classic)

3) Bidirectional VT (answer on tests)

Wellness Wednesday: Where'd the sun go?

If you have a hankering for something lightly medical, this is your day! You have two options:

1) Check this out. Got to love new media.

2) Or, since this is my last Wednesday POD and something very special is happening next week, here's a Wacky Wellness Wednesday pearl for you all! (small medical connection at the end! links embedded throughout!)

 

THE GREAT AMERICAN ECLIPSE:

* The Thing Itself: 

- Why's this one so special? 

= it really isn't. There have been millions. But this one is the first TOTAL solar eclipse to run over the entire US since 1918. We like our astrologyonomy in 'Murika.

- Why do we care?

= They're beautiful

= Soooooo many scientific discoveries: 

* 2000ya: calculated the distance from the Earth to the Moon

* 17th century: What, solar flares are THOUSANDS of miles tall?!

* 18th century: a glass prism splits light into a rainbow because different elementsreact differently!

* 19th century: the sun's made of HOT HYDROGEN GAS (not sodium) and we discovered a new element (HELIUM!)

* 20th century: the weather is related to the sun ie. the winds changed direction during an eclipse!

* 20th century: light bending around the sun confirms the theory of general relativity (whaaaaaat?!)

* What's to come next??

* BTWs history: 

- This is a busy month for astrological phenomena as well as our exploration of the universe

= 40th anniversary of the Voyager 1 & 2 launches that gave us such wonders as:

* the first man-made object to LEAVE THE SOLAR SYSTEM

* an OCEAN below ice on Europa

* volcanoes x100 the power of earth's erupting on Io

* lightning on Jupiter!

* the discovery of 24 (twenty-four!!) new moons in the solar system

* the rings of Jupiter, Uranus, Neptune

* Eclipse in medicine:

- Eye damage: "magnifying glass on a leaf"

= takes ~1.5mins for permanent damage to be done even if not continuous unprotected observation

= cameras and regular glasses won't protect you

= can try the pinhole technique

- Changes in hormones?

- Changes in animals?

- (and if you want more: https://www.nytimes.com/guides/science/how-to-watch-a-solar-eclipse)

Mad Mondays: the meningitis edition

Meningitis: a few morsels

* Symptoms: 

- HA 90% occurence w/ meningitis

- Fever 80%

- AMS 70%

--> TWO of HA/fever/meningismus/AMS = 95% occurrence rate

* Peds vs Adults: 

- Sick kids are sick until proven otherwise

- BGM BGM BGM BGM BGM BGM BGM

- Peds more likely to show first with myalgia, cold or mottled extremities --> rapidly spreading purpura/AMS/hemodynamic instability

= TREAT IMMEDIATELY

= DO NOT WAIT FOR LP (talk to your attending)

- Consider CSF-CRP to help determine viral vs bacterial meningitis; early evidence shows it might help in stain negative samples

- With moderate suspicion, if WBC and/or ESR is elevated, treat immediately (EBM recommendation; consider this in context)

* Diagnosis:

- CSF gram stain only 60-90% sensitive

 

 

* Treatment:

- Steroids?? 

= Highly controversial. EBMedicine says consider giving to adults if HIGH SUSPICION ofpneumococcal infection  (only if you can give with first dose abx too)

- Ceftriaxone, fluids; add other abx prn

- Close contacts: rifampicin (routine) or cipro (women on OCP)