Lots of news articles reporting "Smartphone use on the toilet increases risk of hemorrhoids" citing a small single center study.

Great headlines but also a textbook example of *reverse causation* - a common methodological flaw in observational studies

A 🧵


Reverse causation occurs when we flip the arrow of cause→effect.

Protopathic bias is a subtype: An exposure (often a treatment/behavior) is started because early symptoms are already present, making it look like the exposure caused the outcome.

2/

This is a fascinating case:

A 60 yo man presents with paranoia, new-onset facial acne & cherry angiomas, fatigue, insomnia, ataxia, and polydipsia.

He has an extremely unusual diet.🧂

His labs are👇 (note that anion gap!):

What could be going on?
1/ Turns out he was inspired by a conversation with chatGPT to eliminate all sodium chloride from his diet.

🧪 He decided to replace sodium chloride with sodium bromide instead.

This had some unusual effects…

2/

Well designed RCT shows patients randomized to an exercise program had substantially improved survival after adjuvant chemotherapy for colon cancer.
- 5 yr disease-free survival 80.3% vs
73.9% (HR 0.72)
- 8 yr overall survival 90.3% vs 83.2% (HR 0.63)

This is groundbreaking!
1/ Some deets on the CHALLENGE trial

A 55 center trial done over 15 years (2009-2024) that randomized n=889 people with resected colon cancer after adjuvant chemotherapy to either:
- participate in a structured exercise program
- or to receive health-education materials alone

2/

Tragic news today about former president Biden's prostate cancer diagnosis. I wish him well.

As someone who follows presidential health reporting, I noticed something odd: unlike his predecessors, Biden's physician's never reported PSA.

How to interpret this absence? A🧵
1/


There are two possibilities:
1️⃣ Biden’s PSA was never checked
2️⃣ Biden’s PSA was checked but it wasn't reported

Strictly speaking, not checking PSA could be a medically correct option. Whether or not to test PSA is a complex question and is not the topic of this thread.

2/

In honor of #MayThe4thBeWithYou let's consider the most difficult airways in the Star Wars universe:

1. Darth Vader
Species: human
Vader presents several challenges: Vent dependent at baseline, airway burns from Mustafar, limited neck mobility.
Discuss GOC before saving him
2. Fodesinbeed Annodue
Species: Trog
All airways require teamwork, but intubating Fodesinbeed Annodue's two heads really will require two operators.
Consider double simultaneous awake fiberoptic intubation
Be sure to consent both heads.

Every year, there is a predictable spike in fatal car accidents, medical errors, & heart attacks.

It’s estimated that there are thousands of excess deaths, a 1% increase in energy consumption, & billions of dollars in lost GDP.

The cause? Daylight savings transitions.

🧵

1/ Earth's axis of rotation and orbital axis are not precisely aligned. The 23.5 degree difference - 'axis tilt' - gives us our seasons and a noticeable difference in day length over the course of the year.

2/

Musk is so stupid. Exhibit #10544

There aren’t thousands of 150 year olds getting paid social security. There are null values in a database he doesn’t understand how to read… When unidentified people get admitted to the hospital the default DOB is 1/1/1900. The EHR shows their age as 125 yo.

But *almost* everyone is smart enough to understand this is just a result of missing data…

Important point re indirects:

Unlike other Trump moves, this is arguably GOOD news for researchers!

If the NIH budget is unchanged (a big if), this allocates more money to researchers; if you go from an indirect of 75% to 15% it means you can fund 3 grants instead of 2.

https://twitter.com/nih/status/1888004759396958263

Some context:

Between 1947 and 1965, indirect rates ranged from 8% to 25% of total direct costs. In 1965, Congress removed most caps. Since then indirects have steadily risen.

2/

🚨Apparently all NIH Study Sections have been suspended indefinitely.

For those who don’t know, this means there won’t be any review of grants submitted to NIH

Depending on how long this goes on for, this could lead to an interruption in billions in research funding. With a budget of ~$47.4B, the NIH is by far the biggest supporter of biomedical research worldwide.

Grants are reviewed periodically by committees of experts outside of the NIH.

When these study sections are cancelled, it prevents grants from being reviewed & funded.

#HurricaneHelene damaged the factory responsible for manufacturing over 60% of all IV fluids used in the US, leading to a major national shortage.

As clinicians what can we do to about the #IVFluidShortage and how can we prevent this crisis from happening again?

A thread 🧵
1/
There are many things we can do as clinicians to improve ICU care & reduce IVF use.

1️⃣Don't order Maintenance IV Fluid!
Almost no patient actually needs continuous IV fluids.
Most either need resuscitation (e.g. boluses) or can take fluid other ways (PO, feeding tube, TPN).
2/

New favorite physiology paper: Central Venous Pressure in Space.

So much space & cardio physiology to unpack here including:
- effects of posture, 3g shuttle launch, & microgravity on CVP
- change in the relationship between filling pressure (CVP) & LV size
- Guyton curves!
1/



To measure CVP in space they needed two things:
📼 an instrument/recorder that could accurately measure pressure despite g-force, vibration, & changes in pressure. They built & tested one!
🧑‍🚀👩‍🚀👨‍🚀 an astronaut willing to fly into space with a central line! 3 volunteered!
2/

The media silence on this is deafening.

Did he have a head CT? What did it show?
Did he have stitches? Tetanus shot?

The NYT ran nonstop stories about Biden’s health after the debate but can’t be bothered to report on the health of someone who was literally shot in the head?

https://twitter.com/matt4va/status/1813202802337779731

To the people in the replies who say it’s impossible because of “HIPPA”
1. I assume you mean HIPAA
2. A normal presidential candidate would allow his doctors to release the info. This is exactly what happened when Reagan survived an assassination attempt.
washingtonpost.com/obituaries/202…

You've probably heard "don't give lactated ringers because it raises lactate"

This statement is ~98% false, but there's one crucial practice-changing fact that you need to know.

A 🧵 all about lactic acid and lactated ringers!
1/

First off, we should ackowledge the obvious: Lactated ringers does in fact contain lactate... 28 mEq/L in fact

BUT there's one little detail to remember:
Lactate ≠ Lactic acid

When we measure "lactate" we care about the ACID (H+) which lowers pH & causes organ dysfunction
2/

If you intubate you need to read the #PREOXI trial!
-n=1301 people requiring intubation in ED/ ICU were randomized to preoxygenation with oxygen mask vs non-invasive ventilation (NIV)
-NIV HALVED the risk of hypoxemia: 9 vs 18%
-NIV reduced mortality: 0.2% vs 1.1%

#CCR24
🧵
1/



Hypoxemia (SpO2 <85%) occurs in 10-20% of ED & ICU intubations.

1-2% of intubations performed in ED/ICU result in cardiac arrest!

This is an exceptionally dangerous procedure and preoxygenation is essential to keep patients safe.

But what’s the *BEST* way to preoxygenate?
2/

Results from #PROTECTION presented #CCR24 & published @NEJM.
- DB RCT of amino acid infusion vs placebo in n=3511 people undergoing cardiac surgery w/ bypass.
- Reduced incidence of AKI (26.9% vs 31.7% NNT=20) & need for RRT (1.4% vs 1.9% NNT=200)

Potential game changer!

🧵
1/

I work in a busy CVICU & I often see AKI following cardiac surgery.

Despite risk stratification & hemodynamic optimization, AKI remains one of the most common complications after cardiac surgery with bypass.

Even a modest reduction in AKI/CRRT would be great for my patients.
2/

A slightly tricky blood gas case:

77 yo with respiratory distress, RR 30, SpO2 80% on non-rebreather at 15 lpm

CXR & TTE are unrevealing

pH 7.58 / PaCO2 24 / PaO2 >500 / HCO3 22

MetHb 0% CarboxyHb 0%

The ABG looks like this: The answer is sulfhemoglobinemia.

Sulfhemoglobinemia is a *permanently* modified hemoglobin associated with exposure to TMP/SMX, dapsone, phenazopyridine, & other amino & nitro compounds.

It has an altered oxy-hemoglobin dissociation curve.

2/

This story is absolutely shocking.

Philip Morris International (PMI) spent millions to influence medical education by buying a series of “CMEs” at Medscape!

How else has big tobacco tried to normalize vaping & influence the medical community?

🧵
1/
theexamination.org/articles/medsc… Recently it was revealed that Philip Morris International (PMI) had SPONSORED CME materials about smokeless tobacco products on Medscape.

I had the opportunity to review these “CME” materials & they are pretty shocking!
2/

Damn. Under Trump the White House Medical Unit was a pill-mill. Thousands of ambien & provigil per month.

Worse, for a clinic that doesn’t typically do procedures w/ moderate sedation they sure are they ordering prodigious quantities of morphine, fentanyl, versed, & ketamine…? Honestly, this reminds me of Norman Ohler’s Blitzed.

It’s October - hockey season - so let’s talk about a hockey/pulmonary case:

A previously healthy 17yo presents with dyspnea, frothy sputum, & orthopnea that began after playing hockey.

In the ED he is tachycardic, tachypneic, mildly hypoxic. He has crackles bilaterally.

Dx?
1/ Before we get to the diagnosis, Inhalation of which of the following could explain his symptoms?

2/

Lots of inane comments from Elon/Rohan bros that vaccines don’t prevent disease.

Let’s debunk these claims:
1. Polio - vaccine introduced 1957
ourworldindata.org/grapher/report…

2. Measles - vaccine introduced 1963
ourworldindata.org/grapher/measle… 3. Tetanus - vaccine 1938
cdc.gov/vaccines/pubs/…

4. Diphtheria
researchgate.net/publication/32…

The long awaited #COVIDOUT RCT is now in @TheLancet:
- high risk adults randomized to either metformin (MET), ivermectin (IVM), fluvoxamine (FLV) or placebo.
- MET reduced the risk of long COVID (6.3% vs 10.4%; NNT = 24)
- no benefit with IVM or FLV

thelancet.com/journals/lanin…
1/ COVID-OUT was a large blinded multicenter RCT looking at repurposed oral meds.

The primary outcome was severe COVID; this was one of the *MANY* negative RCTs of ivermectin. (See 🧵👇)

The current study is a planned secondary analysis, looking at the incidence of long COVID.
2/

https://twitter.com/nickmmark/status/1560272414323249152