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She came from a land down under…

Today I had a new patient from Australia, she came in with a few years worth of laboratory results all in SI units.

I knew how to convert mmol/L of creatinine to mg/dl: divide by 88. But converting mmoles/L of urea to BUN? No idea. Converting nmol/L of vitamin D to ng/ml?  Stumped.

Thank the maker for Dr. Google.

  • To convert from creatinine mmol/L to mg/dL divide by 88
  • To convert from mmol/l Urea to mg/dL BUN multiply by 2.8
  • To convert nmol/L 25 OH Vitamin D to ng/ml divide by 2.496
  • To convert mmol of creatinine to mg of creatinine (needed to interpret a 24-hour urine) multiply by the molecular weight, 113
Hat tip to Wikipedia, Dr. Shah at AllExperts and GlobalRPh
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Citrate or Heparin for CRT

As part of my other blogging job (eAJKD) I had the opportunity to interview Drs. Mei-Yi Wu and Ka-Wai Tam who performed a meta-analysis looking at anticoagulation. They examined filter life and other complications of CRT. The interview was conducted by Facebook IM, which was pretty cool and helpful with a significant language and time-zone barrier.

Check out the interview and the article.

By the way Jhaveri, Sparks and the rest of the team have been killing it at eAJKD and have really built a solid blog. Amazing how far they have come in a couple of months. Solid work.

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Don Seldin, Licorice, and the New York Times. Updated x2

The association of licorice, hypokalemia and hypertension is a medical pearl that delights me even though I have never seen a convincing case. However, Ted Lynch had a case in 1987 and presented it to Don Seldin, one of the Gods of nephrology (pdf). The interaction was documented in the New York Times for some reason. It is a well written story.

For those of you fuzzy on the connection between licorice, hypokalemia and hypertension this post by Neil Kurtzman (one of Seldin’s protégées) does a beautiful job explaining it.

And yes, I am working on a metabolic alkalosis lecture.

Update: Here is the FDA warning regarding licorice that was published October 2011 and here is the skinny on American licorice from the good people at Hershey:

Traditionally, “licorice candy” referred to a chewy candy with a distinctive flavor which came from licorice root extract. Today, consumers recognize licorice more as a general description of candy that may be available in a variety of flavors. 

Not all of today’s licorice-type candies are flavored with licorice root extract. Some licorice-flavored candies may be flavored with anise oil instead of licorice extract. Other fruit-flavored candies may be commonly referred to as licorice candy, but do not contain any licorice extract. For example, while people may consider all TWIZZLERS Candy to be licorice candy, the strawberry, chocolate, and cherry-flavored TWIZZLERS Candy do not contain licorice extract. TWIZZLERS Black Licorice Candy is flavored with both licorice extract and anise oil. 

Those licorice candies which contain licorice root extract will typically declare either “licorice extract” or “licorice root extract” as an ingredient on the package.

Hat tip to pkovachmd

Update 2: Here is the link from Melanie regarding the unsuccessful suit involving over-indulgance in licorice and hypokalemia.

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Apple predictions for 2011. How did I do?

Last year I posted my Apple predictions for 2011. Here is the report card.

iPad
The iPad 2 comes out in April after being announced 2-3 weeks earlier.  Not a lot of surprises. It has front and back face-time cameras, weighs less, goes faster and is thinner. It will have a higher resolution screen that Apple will brand a Retina Display but it will not have the same pixel density of the iPhone 4. There wil be three versions, WiFi only, a 3g version with CDMA and a new 4G LTE version from Verizon, AT&T and eventually Sprint.

So three weeks earlier than April 1 is March 11, So I missed the announcement date by 9 days and the release date by 20 days. Yes on cameras, weight loss, thinner, faster, CDMA, GSM and WiFi. No on Sprint, 4g and improved screen resolution
The current iPad, with the low resolution screen, no camera will live on as a low cost model at $399. With the upcoming entry of Palm, RIM and Android in to the tablet space Apple will try to suck all the atmosphere from the room by lowering the entry level price as aggressively as possible. This will upset all the other competitors pricing plans and provide less maneuvering room in the price umbrella under the iPad.
The current iPad did go down to $399, but only to blow-out existing inventory. So no.
By the end of the year Apple will have sold 70 million iPads (total 2010 an 2011 sales) and have a market share of 70+%.
Cumulative sales were 55 million by the end of 2011, so I was over-optimistic by 15 million.


iPhone
iPhone 5 is introduced in June and goes on sale in July. It sports the same form factor as iPhone 4 but has a faster processor, longer battery life, and better front and rear camera. The major new feature is near field communication. Apple sticks with 16 and 32 gb memory options. Prices remain the same.
The Verizon iPhone is introduced with the iPhone 5, the first iPhone 4 for Verizon is the $99 8 gb model introduced along with the iPhone 5.
Verizon introduced the iPhone 4 in February and there was no iPhone 5. The successor of the iPhone 4, the iPhone 4s did indeed share the form-factor of the iPhone 4, had a faster processor, better battery-life and improved back camera. No near-field communication and Apple did add a 64 gb memory option.
The white iPhone makes it first appearance since the 3gs as an iPhone 5.

April 27th the white iPhone 4 is released

Apple will sell a 65 million iPhones in 2011.

Pessimist. Apple sold 93 million iPhones in 2011. I can’t believe they moved nearly a 100 million phones.


My iPhone score card looks like this:

  • iPhone 5 in June/July          No
  • Same form factor                Yes
  • faster                                   Yes
  • better battery                       Yes                                 
  • better cameras                     Yes on back / no on front
  • price remains the same        Yes
  • Verizon iPhone                   Yes
  • Verizon with iPhone 5        No
  • White as iPhone 5               No
  • NFC                                    No
  • Memory remains the same  No
  • 65 million phone                 No
iOS
iOS 5 focuses on the cloud. Music and movies purchased through iTunes can now be streamed over the net. All devices tied to the same apple ID can stream the content, iMacs, Apple TV, iPods, iPads and iPhones.

Pretty much nailed it, except the movies and TV shows.

iOS 5 also gets over the air updating of the OS and over the air continuous back-up, a internet enabled Time Machine back-up service. This major update will better allow iPads to be used without a computer to tether to.

Nailed it

Document management moves forward allowing seamless management of a single document on an iPad then desktop mac and then an iPhone. The document lives in the cloud with synced copies on all of your apple devices.
Nailed it

iOS 5 also adds new APIs that allow software developers to accept voice control and voice feedback for applications.

Voice did debut but it was an iPhone 4s feature not a general feature of iOS. Also it’s a private API that only Apple can access so no public APIs for developers to hook into.

iOS 5 allows FaceTime over 3g.
Nope

I also missed iMessage.

Macintosh
The big story for Mac hardware will be the addition of Lightpeak to replace firewire and display port. By the end of 2011 all Macintosh’s will ship with Lightpeak. RIP Firewire.
Light peak is introduced in Febuary but it did not replace Firewire, it does replace the display port.
MacBook Pros will all go SSDs. There maybe an option for a second drive, a magnetic spinning hard drive but the primary drive will be an SSD. The MacBook will continue to have a spinning hard drive further differentiating the Pro models form the baseline MacBook. This trend will continue across the iMac and MacPro lines both of which will be updated to include an SSD as the primary drive with spinning hard drives as additional drive options.

Not yet. I will include this as one of my 2012 predictions.

Video professionals and HD enthusiasts looking for Macs to ship with Blu-Ray will continue to be disappointed. No Blue-Ray drives will ship in any Macintosh’s.

Yup

MacOS 10.7 Lion will be announced at WWDC to be introduced in the Fall. 10.7 will introduce a new look and feel with a more iOS-like theme.

Yup

The Mac App Store will be a huge hit and will reinvigorate innovation on the PC. The amount of money most people spend on desktop apps will rise and this will intropduce many people to the creativity of the independent Mac Software developer. This will further loosen Microsoft’s and Adobe’s hold on the software market as people get exposed to a myriad of less expensive, less complex and more focused single purpose applications.

Yup

iLife 2011 will add a new application. This application will allow hobbyists, enthusiasts and educators to create interactive content for the iPad. A Hypercard for a new era. See this post.

Nope, not in 2011 and I lost hope and did not include it in my 2012 predictions and then Apple introduces iBook Author. So I had the right prediction but I was early by a couple of weeks.

iPods
In September the big announcement will be that the iPod Nano adopts iOS and becomes the smallest general purpose computer. Apple will open the Nano to a specialized corner of the App store where developer focus on voice and speech for much of the interface.
Wishful thinking.

iPod classic goes away and along with it the last click wheel iPod. The iPod Touch gets a version with 128 gb to replace the lost Classic.

Nope. None of the iPods, not the classic, not the Touch or Nano saw any meaningful upgrade.

Apple TV adds apps that primarily function as channels. So there is the National Geographic app which allows you to view NG video content on your TV.

This looks like a 2012 prediction rather than 2011.

Apple
Apple will not release a release a large screen TV or any other sized TV.

Yup

They will not make a major acquisition, though they will continue to gobble up small, engineering-focussed companies with core technologies.

In 2011 Apple purchased the 3-D mapping company C3 Technologies for 267 million and the Israeli flash memory company Anobit for 390 million dollars. The Anobit purchase was the second biggest purchase in Apple’s history (only NeXT was bigger). I guess this counts as big but I was thinking of a purchase in the billions, like a Yahoo! or other frontline consumer facing company. So I am going to give me a “Yup” for this one too.

The Apple-Google tussel. Apple will not jettison Google or Google Maps.

Yup.

AAPL will hit a high of $415 and finish the year at $395.

Year-end price of 405.00, with a high of 426.70. Missed it by just 2.6% and 2.2%.

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I’m reading the Disappearing Spoon, It’s Nerdtastic

This is a tour through the periodic table. The author is blowing me away with interesting trivia while teaching me chemistry.
Today I learned about the world’s most powerful acid, a super acid with a pH of -31, 1032-times more powerful than stomach acid. He then dazzled me describing the properties of boron based carborone (HCB11Cl11) which is simultaneously the most powerful and gentlest acid. Crazy stuff. The book takes the best anecdotes that professors add to lessons to give context or spice, but its just one anecdote after another, none of the dry, difficult and boring stuff.  A perfect string of pearls.

From The Dynamic Periodic Table

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Acid Base for Med Students, a free iBook. Updated x2

Back in August of 2010 I begged for a content creation system for the iPad and last week Apple delivered iBooks Author.

I just finished converting my Acid-Base handout to the iBook format and the authoring software fits into the rest of the iWork suite. If you know how to use Pages, you will be an iBook Author wiz. The program was solid for a 1.0 release with only one crash in about ten hours of work and I didn’t lose any data. I can’t wait to dig a little deeper and really build some interactive content. I have a feeling, going forward, that iBook Author is going to be my primary content creation tool. For now check out my first iBook. 

Update: Some notes on how to use this file:
  1. You can only use the iBook on an iPad
  2. The iPad must have at least iBooks 2.0 to load the book
  3. The file can be downloaded to a computer and side loaded to the iPad through iTunes, but that seems overly complex compared to just downloading it right from the web sight right on an iPad

Update 2: version of 1.5 is now live with added interactivity.

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New Lecture: Initiation of Dialysis

This is a fellow level lecture. I built it off an old lecture from 2003 or 2004. It is remarkable how much data has emerged since then. Of coarse the IDEAL Trial has put a dagger in the heart of early initiation but the observational data in agreement with abandoning early initiation has also turned.

To fortify this lecture it needs the data on nursing home residents and dialysis outcomes and I’d like to add the recent data on dialysis mortality after the week-end.

All-in-all, its a good foundation.

Initiation of dialysis (PDF, Keynote)