As of this writing, there are over 400 medical applications in the iTunes App Store. Whether you're a health care provider or patient, and whether you have an iPhone or iPod Touch or not, it's worth exploring the impressive range of applications available for this new mobile platform. (Later this year, when iPhone 3.0 is introduced, these applications will be able to interact directly with compatible medical devices, like glucometers and blood pressure monitors.) Here's a brief introduction to three medical apps in the iTunes App Store.

Diagnosaurus. Many medical specialties—and Internal Medicine in particular—require working through a "differential" of possible causes of  a patient's clinical presentation. Diagnosaurus ($.99) provides a polished interface for searching differential diagnoses for over 1000 conditions, divided by organ systems, symptoms, and diseases. As a bonus, at the end of each list is provided a list of links to related differentials. For example, "acute hepatiis" and "cholestatis" are listed at the end of "AST/ALT increased." Much like Wikipedia, you can spent half an hour browsing and clicking through links. For $.99, it's a steal.

ICD9 Consult. Health care providers must frequently scramble to come up with ICD9 codes for unusual or complex diagnoses in order to bill appropriately. ICD9 Consult ($29.99) is an excellent solution for those moments when you don't have time to consult a thick book or spend time seaching online for the right code. It allows you to easily search through the different codes or browse by type of disorder (infections, circulatory, respiratory, etc.) or procedure. At $29.99, it's not cheap, but if it saves you enough time, it's worth it.

WellAdult. The guidelines for optional clinical preventive services for adults—when to perform cholesterol tests or colonoscopies, for example—are scattered among many different expert organizations and are sometimes contradictory. WellAdult ($2.99) provides an easily navigatable database of recommendations from all major organizations for adults of different ages. Click on "Women Ages 50 - 64," for example, and you can easily compare the reommendations of different organizations for testing lipids, blood pressure, vaccinations, and cancer screening. For $2.99, this app is well worth it.

Information overload is an occupational hazard of practicing medicine, especially if you spend time online. There's too much potentially useful stuff out there for one person to process effectively: journals, news sites, RSS feeds, wikis, blogs, webinars, Flickr, Facebook groups, CME courses, Google alerts... And don't get me started on Twitter.

Two of my favorite medical bloggers—Bertalan Meskó from ScienceRoll and Dr. Ves Dimov from Clinical Cases & Images—recently shared their methods for dealing with information overload.



Clinical Cases & Images uses Twitter innovatively, to share interesting items from his feed reader, which he then aggregates into blog posts: "Health News of the Day," for example, and "Selection of My Twitter Favorites." (What's Twitter? Twitter is an instant messaging service, a microblog, a social networking phenomenon, a chatroom, the best crowdsourcing utility ever invented, or a colossal waste of time — depending on who you ask.) Ves also discusses using Google Reader, Google Bookmarks, and shares his backup strategies.

Bertalan Meskó from ScienceRoll writes about using Tweetdeck to filter the 1000 (!) users he follows on Twitter. He also uses Friendfeed and the "best of the day" feature to identify interesting discussions. He mentions Microplaza, Twilerts, and Tweetbeep—three services I've never heard of—to filter out interesting discussions and posts. Bertalan also uses Google Alerts—of which I'm a great fan—to track any content published about him or other topics of interest. He ends with my Life Hacks for Doctors presentation, which has received more than 10,000 views to date. (w00t.)