I gather my belongings: stained white coat, stethoscope, pen light, black ballpoint. I stuff the last two granola bars into my canvas bag. I glance at the clock on the microwave, which is three minutes fast.

Twenty-two minutes until my shift begins. One minute before I will lock the door to my apartment.

Precision is critical: ER shifts change fast and blend together, from late nights to early mornings to mid-afternoons. Suns set and rise, moons disappear then burst again into full spheres of light. But the rhythm remains fixed.

I gulp the last ounces of water and grab my keys just as the clock digits change.

Last week, I reached and surpassed my hundredth shift as a resident physician in the emergency department.

Early on in my emergency medicine residency, I looked forward to my drive to the hospital–twenty minutes of freedom and anticipation. I used to flip from one radio station to the next, scanning for the perfect song to begin my shift. “I Gotta Feeling,” by Black Eyed Peas, perhaps. Or Billy Joel’s “This is the Time.” I was ready to live in the thrill and immediacy of emergency medicine. What excitement will today bring? I’d wonder, singing along with the radio.

Perhaps I’d get my first intubation, drain an abscess, place an IV by ultrasound guidance, insert a central catheter or thread an arterial line. Perhaps I’d see one of the critical, life-threatening abbreviations that we worry about in the emergency department: ACS (acute coronary syndrome–a threatened heart attack), PE (pulmonary embolism)…the list goes on.

Those first hundred shifts were filled with so much novelty that I hardly had time to register what I was really doing: caring for critically ill patients. As I focused on learning and achieving, the intimate realities of grieving families and suffering patients slipped my mind.

But somewhere along the way, what was novel became routine. The rush of adrenaline I felt at the words “Full Trauma now!” slowed to a trickle. The sense of accomplishment at performing a new procedure dwindled. I began, without even realizing it, to focus on my patients. I started to imagine the course of their lives, suddenly and permanently changed by a single visit to the ER–and to me.

Now I dread my drive to the hospital.

Today I drive with the windows open, listening to the music but not singing–not even processing the song. Certainly not bothering to change the station. What tragedy will today bring? I wonder.

In the last week alone, the answers have been grim. A sixty-year-old woman with a new diagnosis of ovarian cancer. A girl struck by a car while walking across the street. An elderly gentleman who arrived at the hospital dead. A teenage girl who’d suffered a sexual assault. A young man with multiple gunshot wounds.

As I walk in through the double doors, I need a boost of optimism. I look at the board–a long list of people who’ve wound up here, instead of home, at the end of their Labor Day Weekend. In search of a patient I might be able to heal quickly and efficiently, I spot one: a middle-aged woman with chest pain.

Glancing around, I see her in an exam room. She sits in a stretcher, pale but comfortable, and her vital signs look good. Here’s someone I can fix, I think. I can treat her pain and send her home, or to the catheterization lab or somewhere in between.

I inhale, enter the room, introduce myself.

She is very pleasant. She tells me about her chest pain–when it began, what it feels like and so on. Then she mentions, as an aside, that she’s in a nursing home.

I inspect her closely. She seems too young for a nursing home. And she doesn’t appear sick. I am perplexed. We continue talking about the chest pain for a while. Then I begin to ask the more probing questions.

“So how long have you been at the nursing home?”

She pauses. “Well, since the accident.”

I take a deep breath. “And what kind of accident was it?”

“It happened at an outside pool. I was standing at the ledge. I didn’t realize how shallow it was. And…” Her voice trails off.

As I look at her, her eyes well with tears.

“I’m sorry,” I say softly, feeling that these words are only a formality–only syllables to fill the space between us.

“Do you think I’ll ever walk again?” Eyebrows arched, she shows me that she can wiggle her toes on both feet.

“What have your doctors said?” I ask, returning to safe ground, the experts’ advice.

“My doctors don’t say anything.”

Will she walk again? The truth is, I hope she will. I can recite grim probabilities and statistics, but she’s only one person–and she might just be the one in 100,000 who beats the odds. I don’t want to take away her hope–it’s keeping her alive, maybe even helping her heal.

“I think the progress you’ve made is encouraging,” I say. “Keep working on it. For now, let’s talk about your chest pain a little more.” She agrees, and we return to the bloodwork, EKG and chest x-ray that will keep us both occupied for the next hour.

As I leave the room, images of her story flood my mind. A dive into cool, blue water. Those black tiles at the bottom. The “No Diving” sign printed in bold letters along the ledge of an outdoor pool.

I imagine sitting in the lifeguard stand, where I sat for so many years as a young girl, and watching this woman dive to her tragedy.

As a swimmer from the age of four, I remember diving from the starting block hundreds, even thousands, of times–adjusting my angle precisely, leaping far out into the water, tucking my head, stretching. If only I could have taught her how to dive, or simply have blown my whistle to warn her in time…

I’m here now to take care of her chest pain, I remind myself. But somehow that isn’t enough. The images continue to flash.

A hundred shifts in, and I still haven’t learned how to suppress them. I wonder if I ever will.

A hundred shifts in, I have fine-tuned my instincts as a physician. I have learned the procedures that are required of me. I have mastered the art of working fast and prioritizing the sickest patients. I have listened to thousands of patients’ stories.

I’m a hundred wiser, perhaps, but not a hundred tougher.

And as I continue to pass these mile-markers, I wonder where I’m headed. Not to a final destination, I now realize. There’s no distinct end to the path I’m on. In fact, I’m starting to feel that it’s not so much a path as an intricate web, woven of the silken strings of people’s lives spinning themselves around me–holding me in place to face and feel my patients’ pain and vulnerability, and my own.

Anne K. Merritt is an emergency medicine resident. This piece was originally published in Pulse — voices from the heart of medicine, and is reprinted with permission.

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