Chances are that by now you have heard about the many surgeries major hospitals across the U.S. have chronicled live (in 140 characters or less) via the increasingly popular social media site Twitter.

The site's founders did not come by that 140 characters limit arbitrarily, of course, it just happens to be the same limit for the text messages we send and receive via mobile phones. Twitter is one of the first and certainly most popular social media site that was built around mobile phone functionality -- users can "tweet" directly from their mobile phones through text messages -- if they don't have a smartphone and Web browser. Users can also have Twitter send them updates from other users via text message, too. 

Using Twitter to live-stream surgeries has brought some hospitals a good deal of (mostly positive) attention. In some cases, hospital groups have tripled their number of followers, adding thousands more, to their Twitter feeds. Critics claim that tweeting surgeries is just a PR stunt that is perhaps a waste of time. Proponents extol participating hospitals as more "transparent" than their non-tweeting cohorts.

Some have linked the practice of live-tweeting surgeries to a doctor's role in educating the community about medical procedures: Twitter's 140 character limit encourages the surgeons or their PR counterparts to report on the surgery in layman's terms. Other groups position the live tweets as an educational channel for other doctors, medical students and patients alike.

Whatever the reasons, it seems that at least for now live tweeting surgeries will continue.

While there are likely to be other examples of live tweeted surgeries, we compiled a timeline of the most notable examples from the past eight months. Read on to re-visit how surgeons met Twitter. Be sure to let us know what you think will come of this trend.

October 29, 2008: Robert Hendrick, co-founder of change:healthcare live tweeted surgery that was performed on him to remove his varicose veins. Hendrick was tweeting live from the operating room in what many believe to be the first use of Twitter during live surgery. More

Sample Twitter post from the surgery: @jrh3 "2 lasers in top part of left leg. Little bit of sting not bad. Getting a tattoo is worse."

November 13, 2008: Robert Hendrick live tweeted his laser ablation surgery at the Surgical Clinic in Nashville. Part II of his live-tweeting and believed to be the second occurrence of tweeting during live surgery. More

Sample Twitter post from the surgery: @jrh3 "Uh oh. The staff at the doc's office is following me on twitter now."

December 9, 2008: Robert Hendrick live tweets about his varicose vein surgery, Part III.

Sample Twitter post from the surgery: @jrh3 "Looks like the doc is pulling lots of little worms out of my legs. Got video of him tugging on them. YouTube later."

February 9, 2009: Doctors at Henry Ford Hospital in Detroit tweeted an operation to remove a tumor from a kidney. Dr. Craig Rogers, the lead surgeon in the Henry Ford surgery, said the impetus for his Twittering was to let people know that a tumor can be removed without taking the entire kidney. The surgery and accompanying tweets are a public relations coup, with many major media outlets covering the event. More

Sample Twitter post from the surgery: @HenryFordNews "the tumor has been completely excised, 20 minutes left to repair the kidney"

March 18, 2009: Henry Ford Hospital tweeted an awake craniotomy, which involved speech mapping and allowed surgeons to assess, in real time, precisely which parts of the brain had a direct impact on the patient's speech function. More

Sample Twitter post from the surgery: @HenryFordNews "He is talking about where he works. He is strapped to the OR table but can move is arms and hands a little"

April 2, 2009: Staff at Sherman Hospital in Elgin, Illinois used Twitter to track a surgical team performing a laparoscopic hysterectomy on a 48-year-old woman. Marc Battaglia a team member of Sherman Hospital's PR firm, tweeted about the hysterectomy surgery from his phone at Sherman Hospital in Elgin. More

Sample Twitter post from the surgery: @ShermanHealth "Dr. Chatterji just announced the procedure is done and looks beautiful!"

April 16, 2009: Aurora Health Care produced a live "twitter-cast" of a bi-lateral knee replacement. The center positioned the stream as an educational broadcast. Aurora's total number of Twitter followers grew from 930 followers the week before to 2,240 by the end of the surgery. Aurora posted more than 250 tweets and received 180 replies with questions and comments. "Good Morning America" morning news show even ran a segment on the Twitter-casted surgery. More

Sample Twitter post from the surgery: @Aurora_Health "dr will now shave off the back half of the kneecap"

May 18, 2009: Children's Medical Center in Dallas provides Twitter updates from the operating room Monday as 3-year-old John Gilbreath receives a kidney transplant from his father. The hospital dubs the surgery/Twitter-cast as a first-time for transplant surgery. More

Sample Twitter post from the surgery: @ChildrensTheOne "The kidney is making urine. Everyone in the OR is excited!"

June 30, 2009 (planned): Christiana Care Health System plans to webcast and Twitter-cast two total knee replacement surgeries, back-to-back to demonstrate different techniques. More

Follow @ChristianaCare for the live Twitter stream planned for late next month.