"How can you make me wait so long?" she said. "You don't know what you're doing. I want a real doctor." I apologized and tried to be soothing, but she kept insulting me. I excused myself to figure out what to do.

When a colleague asked me how I was doing, my emotions welled up and I started to cry. She kindly took over.

Running late and keeping patients waiting are common experiences these days in medicine.

We are forced to see more patients in less time. Patients expect, rightly so, the best care - but they also expect it to be on time. And that to me, more often than not, is an insurmountable challenge.

Theoretically, doctors should know better. We're numbers-oriented people and have been trained to be punctual. Why shouldn't we run on time to see our patients?

But the limits of health care these days - the low reimbursement rates and the shortage of physicians - put pressure on our schedules, which become overbooked. We also fit in emergency patients and answer urgent phone calls between appointments.

Nowadays, patients are double-booked into 15-minute time blocks. This is to hedge for no-shows and keep "volume" up so the office can be profitable.

But problems arise. That's the nature of medicine. People come in with ailments, and some don't fit into a neat time slot.

Patients aren't clients and you don't get serviced. It's not like a Jiffy Lube, where you expect your car to be oiled up in a fixed amount of time, or a McDonald's drive-through, where many items are pre-prepared and served quickly.

Some patients have questions that take up more than the few minutes allotted. That puts you back 5 or 10 minutes more for each of those patients. Or perhaps it's a good-weather day and 10 patients are no-shows instead of the usual 20. And so, there's a wait.

Some days I will be zooming back and forth into patients' rooms and hear one tirade after another.

I genuinely feel sorry for making them wait and I let them know that.

Then, once I show my focus is on them, their anger often dissipates. They know I'm present for them.

Still, there are the curmudgeonly patients who dwell on it, like the patient who made me cry. I suspect they think the doctors are dawdling. Or worse, that we don't respect their time. I still try to give them my best care, but to be honest, it's less enjoyable to take care of patients giving me a frowny face.

As part of a big medical center, I don't have much control over how patients get booked. But even if I did, this type of mathematical equation is far beyond me. It's an industrial engineering problem. I do know that office managers are always working on ways to improve patients' experience.

For example, we have a "pumper pod" in one clinic where one resident sees all the quick, urgent patients and the others spend more time on the complicated ones.

Still, we're often stuck with delays. In the meantime, my colleagues and I can offer some tips for patients to cope with the system.

Hint No. 1: Book your appointment at the beginning of the day or afternoon (8 a.m. or 1 p.m.). That way, you're there before any delays pile up. In other words, think of the airlines: "I never book a flight at the end of the day," says one attending. By then, all the delays have stacked up and you're more likely to be stuck on the runway.

Hint No. 2: If things do get backed up, take along something to read. That People magazine from 2006 in the waiting room isn't as exciting as the book you're reading, so why not take it? Or come with Sudoku. Don't sit there empty-handed. You'll work yourself into a tizzy.

Hint No. 3: Expect to wait. And if you don't, you'll be pleasantly surprised.

Hint No. 4: Think positive: If you do have to wait, at least you have an appointment and will eventually be seen. It's not like Department of Motor Vehicles where they shut the doors at 4:45 and throw everyone out.

And call this Hint No. 5: Have faith. We're doing our best and trying to get you in on time. I promise.

Rachel K. Sobel, a third-year resident of the Wills Eye Residency Program at Thomas Jefferson University, will be writing about her experiences every other week.