As a teacher in an academic institution, I'm accustomed to frequent visitors to the OR. Medical students, therapists, athletic trainers and, Lord knows why, other surgeons frequently observe my surgeries in the spirit of learning. Teaching is a role I do take seriously, yet each visitor carries some element of risk.

• The traffic jam. There's good data indicating that frequent OR traffic increases infection risk. More people means more carriers of bacteria. Some unfortunate souls are deemed as shedders and exude more bacteria than my daughter's pet rat. When my room gets too crowded, we fasten a do not enter sign across the door (see "Crowd Control").
• The contaminator. Despite my best efforts, there is always a looming observer who saunters too close to the surgical field and touches either my gown or one of my assistants. Ouch! Yes, I have a PhD in sterility, and surgery is one discipline where it pays to have at least a little obsessive compulsive disorder. We have a saying in orthopedics: Infections are forever. Not entirely true, but close. After I politely reprimand the offender and don my sterile sleeve, I attempt to finish the case and pray I won't have a repeat offender. I then reinforce to the audience that the surgical no-fly zone is at least 3 feet away from me. If the student has bad breath, it's 6 feet.

FULL HOUSE
Crowd Control

Even though I perform mostly arthroscopic, low-infection-risk surgery, when my OR gets as crowded as Times Square, I say "no mas!" and put the kibosh on more observers. The nurses gladly accommodate my request and will place this do not enter fabric sign on the door, replete with Velcro fixation. It works.

— John D. Kelly IV, MD

• The fainter. It happens every year: Some poor soul witnesses surgery for the first time and in a matter of seconds passes out. Hopefully there is someone nearby who can ensure that the victim has a soft landing, but sadly at times a loud thump is what first brings my attention to this occurrence. A flurry of nursing activity and code blue soon follows, whereupon the poor faintee is revived and usually dispatched to the emergency room for a complete concussion evaluation. Maybe we should consider an observer zone with floor mats. Here is one example where a crowded room pays off. Last month the room was so crowded, a student passed out at 10 a.m. and didn't hit the floor till noon.

For science's sake
Despite the perils of letting visitors observe, we're all obliged to teach and inform the next generation of nurses and docs. Until virtual reality becomes a reality, I'll continue to eat the risks of teaching in the name of science, as long as my infection — and concussion — rates remain low.