'Hi, sorry to keep you waiting," said Heidi Zwick, as she extended her right hand. "I was afraid there'd be nothing going on. But I have a helicopter coming in and I had an upset parent on the phone and . . . ."

I lost the rest of that sentence as I tried in vain to keep up with its author. Among her other talents -- and she has many -- Heidi Zwick walks very quickly through the halls of Children's Hospital. It's a skill she has developed of necessity, since at night, she runs the show.

Throughout our annual fund-raising campaign on behalf of Children's Hospital, I'm forever running my mouth about how well Children's heals kids. I'm forever telling the stories of new machines, doctors, kids and parents. Here for a change is the story of an unsung hero -- the night nursing supervisor at Children's. She's a woman who, by her own account, "gets anything and everything."

Heidi Zwick's primary responsibility is to be sure the patients and staff get what they need in terms of help, supplies and encouragement. She roves the hospital constantly, dropping in every couple of hours at each nursing station, where she reviews the patients one by one with the nurse in charge. Heidi's journeys are a study in diversity -- and in difficulty.

The other night, at 4-Blue, the nurse in charge had a toughie. One boy's parents smelled of liquor, and they were in the room with him. Could the nurse say anything? Should she? Heidi counseled her not to as long as the child was in no danger.

On the same wing was a 15-year-old who had signed himself in for surgery the next morning. But his stepfather had refused to sign the consent form. After some digging, conducted in pidgin Spanish, the nurse learned that both the stepfather and the patient were illegal aliens. What to do? Nothing, advised Heidi. Call the legal office in the morning.

And on it went. Four-Orange had the strangest case of the night: a 12-year-old boy who had been playing football and who had been bitten on the hand. Emergency had the saddest: a four-month-old girl whose breathing was dangerously irregular. Intensive Care had the most encouraging: a newborn who had been through open heart surgery just hours before, and was recovering beautifully.

Tramp, tramp, tramp . . . . A nurse needed a bottle of formula but didn't have time to go down to the storeroom to get it. Heidi got it for her . . . . Tramp, tramp, tramp . . . . A mother needed a lifesize doll on which to practice cardiopulmonary resuscitation. Heidi found one . . . . Tramp, tramp, tramp . . . . A night-shift nurse had called in sick. Heidi reshuffled the schedule.

"The difference in this job, and what I like best about it, is that you're the only one (in authority) who's here," said Heidi, who is 32 and has worked at Children's for nine years, three of them as night nursing supervisor.

"The patient contact is less, and I still miss that. But this has different challenges. The most ama-a-a-a-zing things happen."

PEEP-PEEP-PEEP-PEEP. As if to prove it, Heidi's beeper went off in midsentence. "Please call the E.R., 5203," said a tinny voice. Heidi did.

"Hi, it's me," she said. "Uh, huh . . . . Okay . . . . I'll be right down."

"Staffing problem," she said, as she summoned a staff-only elevator. And then she added:

"You know, I think any one of us could run any major hotel on the East Coast without any problem."

Don't try, Heidi. You're doing too well where you are.