The learning curve: like everyone else, surgeons need practice. That's where you come in.

The patient needed a central line. "Here's your chance," S., the chief resident, said. I had never done one before. "Get set up and then page me when you're ready to start."

It was my fourth week in surgical training. The pockets of my short white coat bulged with patient printouts, laminated cards with instructions for doing CPR and reading EKGs and using the dictation system, two surgical handbooks, a stethoscope, wound-dressing supplies, meal tickets, a penlight, scissors, and about a dollar in loose change. As I headed up the stairs to the patient's floor, I rattled.

This will be good, I tried to tell myself: my first real procedure. The patient -- fiftyish, stout, taciturn -- was recovering from abdominal surgery he'd had about a week earlier. His bowel function hadn't yet returned, and he was unable to eat. I explained to him that he needed intravenous nutrition and that this required a "special line" that would go into his chest. I said that I would put the line in him while he was in his bed, and that it would involve my numbing a spot on his chest with a local anesthetic, and then threading the line in. I did not say that the line was eight inches long and would go into his vena cava, the main blood vessel to his heart. Nor did I say how tricky the procedure could be. There were "slight risks" involved, I said, such as bleeding and lung collapse; in experienced hands, complications of this sort occur in fewer than one case in a hundred.

But, of course, mine were not experienced hands. And the disasters I knew about weighed on my mind: the woman who had died within minutes from massive bleeding when a resident lacerated her vena cava; the man whose chest had to be opened because a resident lost hold of a wire inside the line, which then floated down to the patient's heart; the man who had a cardiac arrest when the procedure put him into ventricular fibrillation. I said nothing of such things, naturally, when I asked the patient's permission to do his line. He said, "O.K."

I had seen S. do two central lines; one was the day before, and I'd attended to every step. I watched how she set out her instruments and laid her patient down and put a rolled towel between his shoulder blades to make his chest arch out. I watched how she swabbed his chest with antiseptic, injected lidocaine, which is a local anesthetic, and then, in full sterile garb, punctured his chest near his clavicle with a fat three-inch needle on a syringe. The patient hadn't even flinched. She told me how to avoid hitting the lung ("Go in at a steep angle," she'd said. "Stay right under the clavicle"), and how to find the subclavian vein, a branch to the vena cava lying atop the lung near its apex ("Go in at a steep angle. Stay right under the clavicle"). She pushed the needle in almost all the way. She drew back on the syringe. And she was in. You knew because the syringe filled with maroon blood. ("If it's bright red, you've hit an artery," she said. "That's not good.") Once you have the tip of this needle poking in the vein, you somehow have to widen the hole in the vein wall, fit the catheter in, and snake it in the right direction -- down to the heart, rather than up to the brain -- all without tearing through vessels, lung, or anything else.

To do this, S. explained, you start by getting a guide wire in place. She pulled the syringe off, leaving the needle in. Blood flowed out. She picked up a two-foot-long twenty-gauge wire that looked like the steel D string of an electric guitar, and passed nearly its full length through the needle's bore, into the vein, and onward toward the vena cava. "Never force it in," she warned, "and never, ever let go of it." A string of rapid heartbeats fired off on the cardiac monitor, and she quickly pulled the wire back an inch. It had poked into the heart, causing momentary fibrillation. "Guess we're in the right place," she said to me quietly. Then to the patient: "You're doing great. Only a few minutes now." She pulled the needle out over the wire and replaced it with a bullet of thick, stiff plastic, which she pushed in tight to widen the vein opening. She then removed this dilator and threaded the central line -- a spaghetti-thick, flexible yellow plastic tube -- over the wire until it was all the way in. Now she could remove the wire. She flushed the line with a heparin solution and sutured it to the patient's chest. And that was it.

Today, it was my turn to try. First, I had to gather supplies -- a central-line kit, gloves, gown, cap, mask, lidocaine -- which took me forever. When I finally had the stuff together, I stopped for a minute outside the patient's door, trying to recall the steps. They remained frustratingly hazy. But I couldn't put it off any longer. I had a page-long list of other things to get done: Mrs. A needed to be discharged; Mr. B needed an abdominal ultrasound arranged; Mrs. C needed her skin staples removed. And every fifteen minutes or so I was getting paged with more tasks: Mr. X was nauseated and needed to be seen; Miss Y's family was here and needed "someone" to talk to them; Mr. Z needed a laxative. I took a deep breath, put on my best don't-worry-I-know-what-I'm-doing look, and went in.