And when the three-day explosion is over, everyone returns to the operating room to work side by side for another year, to collect 52 more weeks of stress individually before letting it out again together.

A third striking effect of the hospital is boredom. A hospital is one of very few work environments in which people are forcibly confined to the building all night, whether there's anything to do or not. Often, when the patients are asleep and the E.R. is quiet, doctors and nurses find themselves sitting around, just waiting for something to happen.

Of course, there are many ways of passing the time -- reading, crossword puzzles, Game Boys. And sometimes, when the floor is empty, when there's a bedroom right down the hall that only you have the key to and when one of your co-workers shares with you a mutual attraction, there doesn't seem to be a reason in the world not to disappear for a few minutes.

Of course, it's vitally important to keep your pager and your wits about you when doing this, lest you end up like one now-famous resident who not only showed up to an emergency code late but arrived unzipped and unbuckled.

The fourth, and perhaps most important, feeling generated by the hospital is understanding. Simply because of the specialized nature of the job, a nonmedical person, no matter how hard you try to explain it to him or her, will never truly understand what we go through in a day at work. It's not that someone couldn't comprehend it; it's just that the emotions, the proximity to illness and death and the feeling of never knowing exactly as much as you think you should even when others are depending on you for their lives are an experience unique to medicine. And as much as one wants one's girlfriend or husband to understand exactly what it is one goes through, short of sending them through med school, the loved one simply never will.

Furthermore, many doctors spend more time at the hospital than at home -- they sometimes get to know the staff as well as or better than they know their own families. And when you finally do get to spend time at home, you often don't feel like recounting every single thing that happened at work; sometimes, you just want to leave it all behind.

But co-workers, who are there with you every minute of every day, not only understand but are going through the same events and sensations, often right by your side. That creates a very strong bond, because you share a connection that doesn't need words or explanation.

A resident I knew loved her boyfriend so dearly that it became legendary. We used to hear about this guy so much, we felt we were not just friends with him but that we'd grown up with him. Every year, I still remember his birthday.

But one day this resident found herself in the rare situation of running a code on a young overdose patient who, if the code was successful, would actually have a good chance of continuing on with a normal life.

The code lasted almost an hour and a half, 90 minutes of frenzied pumping, injecting and shocking. But no matter what the resident did, the patient's systems were just too depressed, and as the effects of each injection wore off, he would once again continue his slow, inexorable descent toward death. Finally, despite innumerable electric shocks to his heart and what seemed like gallons of excitatory medications, the patient died, with the resident still thrusting rhythmically on his chest.

Her shirt was soaked through with sweat. Wayward strands of hair fell everywhere, some plastered to her face with what might have been tears. She took several long, deep breaths, straightened herself up and slowly walked from the room, motioning for one of the male respiratory technicians to follow her. They disappeared down a hallway and into the call room, from which a soft symphony of creaking ensued.

Ten minutes later she emerged, posture erect, hair combed, and went back to work. Not a word was ever breathed of the incident again.

Now, I don't mean to give the impression that the hospital is a den of sin, threatening to turn anyone who looks back at it into a pillar of salt. Plenty of people are able to work there, day in and day out, without causing an overflow in the obstetrics ward or a backlog in the STD clinic.

Sex is a daily, undeniable part of everyone's life, even if only in our thoughts. It just happens that the hospital, a building and a culture that are unparalleled in our civilization, creates in us a unique set of pressures and emotions that every once in a while pushes sex from our thoughts right into our actions. Just as I learned so long ago on TV.