At my five-year college reunion recently in New York City, my friends all congratulated me on finishing medical school. Then they asked the same question:

"So, how long will residency be?"

I answer calmly. They responded with a mixture of sympathy and amazement.

"Eight years? Eight years of 80-hour workweeks?"

This, I could see, was a stunner for friends who already had impressive jobs with handsome titles, hefty salaries, and beautiful lofts in downtown Manhattan.

A few even jumped ahead to the next milestone:

"So, you won't even be done by our 10-year reunion," a few said, eyes wide.

When you spend your days and nights with fellow medical students, the numbers of residency become just another part of reality. The years and hours pale next to our real focus: the responsibility and challenge of helping patients who trust us to do all we can to return them to their normal lives and loved ones.

The timeline is too long and the experience too strenuous to take it in all at once.

Still, I can't help but look ahead. I finished medical school at 27. If all goes according to plan, I'll be 35 when I complete my residency at the University of Pennsylvania and I'm a fully qualified cardiac surgeon.

Sometimes, I think about all that could happen in these next eight years. When will I have time to get married and start a family? Having kids during residency would mean I'd likely miss all kinds of important milestones, not to mention forgoing many vacations, holidays and family gatherings. But do I want to wait eight years to start a family?

And after I'm basking in the light at the end of this long medical training tunnel, will I find the personal and professional fulfillment I hope for?

Like I said, it's a lot to take in.

But whenever I have these doubts, I think back to my junior year of college, when I first questioned my choice to go into medicine – in large part because of the long path ahead of me.

I reached out to a friend's father, a man who always conveyed real wisdom, not just information. I trusted him for a frank look at my options. We decided to meet one Monday afternoon.

Not once during a two-hour conversation did he talk about medicine or any other career options. He made no recommendations, offered no advice. Instead he shared an allegory, sketching it out on a napkin as he spoke.

Everyone's life is a parking lot that has a single entrance and an exit, he began. We all enter at the same spot, farthest away from where we would like to park, and slowly drive to our destination. As we pass by open spots and watch others choose to take them, we keep asking ourselves rather to grab a nearby space, or keep aiming for our dream location, even risking that we won't find an opening there.

He said that in his experience, as long as he persisted on taking that risk and driving on, he found that the spot he wanted most would somehow be open to him.

As I face another long journey, I know that some nights, I will surely find myself wondering whether I'll find that spot I've dreamed of for so long.

But unlike that long ago Monday afternoon when my friend's father did so much to guide me, I don't feel lost.

Looking back on the last four years of medical school, I am glad that I fought to achieve the goal that was right for me. I believe in my choice to pursue cardiac surgery and the reasons I want to help patients. These convictions help me find meaning and fulfillment in long work days.

Many of us face uncertainties and anxieties at work as well as at home. But the important thing is to strive and push forward despite them, because the most assuredly open spot in this entire journey is the one located closest to our dreams.