When I'm on the night shift, all the department heads can't sleep.

As soon as Qin Hai finished speaking, a small space immediately became clear next to the bench outside the nurses' station.

The sky was already turning gray.

Before the night shift was even over, the smell of sweat from school uniforms wafted into the emergency room entrance.

The PE teacher leading the group was helping the boy up, trying to guide him to a chair. The zipper of his dark blue tracksuit was half-open, and the plastic whistle on his chest bounced with each movement.

The night shift nurse has already brought over the mobile bed.

The bed wheels rolled over the IV patch on the floor, making a soft, sticky sound.

"Lie down."

The boy looked up at her, his face and lips deathly pale. His white school uniform short-sleeved shirt clung to his back, the collar soaked with sweat, and the school badge on his chest was askew, as if he had just been dragged along.

His right hand was still pressed against his chest, his knuckles were long and jutting out from his thinness.

The teacher held onto the edge of the bed with one hand and clutched her phone with the other, trying to get the words out.

"Doctor, he just did his morning run at school, the 800-meter race."

"After he finished running, he said his chest hurt. I thought he had run too fast, so I helped him sit down for a while."

"Then he rolled his eyes and started sliding down, which scared me to death."

The boy was helped onto a portable bed.

There was an old tear in the mattress cover, and the transparent tape stuck to the edge was peeling up.

His shoulders were still trembling slightly as he lay down.

Qin Hai didn't let the teacher continue.

"Name, age".

The teacher looked down at his phone.

The school access card is stuck to the side of the phone case, and the corner of the card is worn white.

"Lu Yifan, sixteen years old, first year of high school."

Lin Ye had already pushed the electrocardiograph machine over. When the electrode packaging was torn open and the film was placed on Lu Yifan's chest, the boy flinched.

The skin was cool and damp with sweat, and the edges of the film quickly became glossy with moisture.

The night shift nurse wrapped the blood pressure cuff around her arm.

The cuffs bulged out.

The numbers jumped a few times.

96/58.

Heart rate 127.

Blood oxygen 97%.

Bedside blood glucose level was 5.4.

The lancet hasn't been put into the sharps box yet.

Lin Ye looked at the 5.4 on the blood glucose meter screen and used his thumb to put the cap back on the lancet.

The next glance fell on the boy's hand pressed against his chest.

When the teacher heard that the blood sugar was normal, she loosened her grip on her phone.

"So, is it because you didn't have low blood sugar? Could it be that you ran too fast? When the kids rush around in the morning, I panic too."

Qin Hai glanced at him.

That glance wasn't heavy.

But the teacher stopped talking on her own.

Lin Ye pulled out the first electrocardiogram (ECG) chart. The paper was still warm from the machine, and the black waveform moved forward frame by frame.

Just as the teacher was about to speak, Qin Hai raised his hand. Lin Ye didn't rush to speak; his fingertips first stopped at the rhythm section, then moved towards the chest connector.

The T waves from V4 to V6 are very low and droop downwards.

The voltage in the left precordial leads was also high.

Some waveforms don't look like the waveform of a child who has just run and is tired.

We can't make definitive statements just by looking at voltage.

But next to this piece of paper were the words "fainting after exercise".

Qin Hai reached out his hand.

Lin Ye handed over the electrocardiogram chart.

Qin Hai glanced at it twice, then his brows furrowed.

"Reattach it securely, and check it again."

The night shift nurse pressed the edge of the electrode pads again.

The rubber surface was sticky with sweat, and the edge curled up a little.

Lin Ye took a dry gauze and wiped his skin.

The second electrocardiogram came out.

The waveform did not disappear after the electrode was reattached.

The teacher stood at the foot of the bed, her fingers still clutching her phone, the screen flashing on and off.

"Doctor, is he not having a stitch?"

Qin Hai did not answer immediately.

He put the two electrocardiogram sheets together and placed them on top of the resuscitation record folder.

The corner of the paper was held down by the clip, but it still curled up slightly.

"I had chest pain and felt dizzy after exercising, and my electrocardiogram was still not clear."

Qin Hai's fingers pressed against the corner of the paper.

"This isn't something you can just sit in the hallway and wait and see."

The teacher's knuckles, which were holding the phone, slowly turned white.

"Fainted?"

His gaze fell on the two electrocardiogram charts.

"It only takes a few seconds."

"Even a few seconds can make you dizzy."

Qin Hai's voice was very flat.

"Especially after exercising."

Over in the emergency room, the suction machine stopped for a moment.

The elderly patient with upper gastrointestinal bleeding was still relying on medication and blood transfusions to maintain his blood pressure.

A gastroenterologist is bending down to fill in endoscopic records.

The second bag of red blood cells had just arrived, and the cold chain box wasn't even closed yet; water droplets on the ice packs were already sliding down the box walls.

On the other end, Lu Yifan's chest was still rising and falling, and the electrode patches on his chest rose and fell gently with his breathing.

Lin Ye looked down at the boy.

"Does it still hurt?"

Lu Yifan's throat moved.

"A little."

His voice was very soft.

After saying that, he pulled his fingers further into the hem of his school uniform.

"Where does it hurt?"

He pressed his hand behind his sternum.

"here."

"Does it hurt while running, or does it hurt after running?"

"The last half lap."

The boy's eyelashes fluttered.

"I was a little out of breath and my vision went black."

The teacher took half a step forward, and the whistle swayed in front of his chest.

"They sprinted in the last half lap. He's not bad at sports, but he was probably pushing himself too hard."

Lin Ye did not look at the teacher.

He continued to ask Lu Yifan:

"Have you ever experienced chest tightness, heart palpitations, or blurred vision when running or playing sports?"

Lu Yifan hesitated for a moment.

"Once."

The teacher was stunned.

Why didn't you tell the teacher?

Lu Yifan looked away.

Just for a moment.

"I'll be fine after sitting for a while."

Lin Ye's pen stopped on the notepad.

A small black dot was pressed into the paper.

You'll feel better after sitting for a while.

Lin Ye wrote that sentence down as well.

The pen tip was pressed down even deeper than the previous line.

Qin Hai put the stethoscope into his ear.

He bent down to listen to the precordial region of his heart.

It was noisy in the emergency room.

The monitors, footsteps, and telephones were all ringing.

He listened for a long time.

After listening, he gently helped the boy sit up a little.

As soon as Lu Yifan moved, the color of his lips faded even further.

The night shift nurse immediately supported his shoulder.

Don't force yourself to be strong.

Qin Hai listened to it again.

This time, he didn't let the boy sit for too long.

"Lie back down."

When Lu Yifan lay down, the back of his school uniform was pressed against the bed sheet, and the sweat stains were pressed into a patch.

Lin Ye saw his hand resting on the edge of the bed.

Long, slender fingers.

Prominent wrist bone.

When the thumb crosses the palm, it almost extends beyond the edge of the palm.

Lin Ye did not write it as a diagnosis.

The pen tip paused for half a second at the edge of the recording paper.

A light blue system frame appears in the corner of the field of view.

[New high-risk factor: Exercise-related chest pain/fainting.]

[Risk areas: Cardiogenic syncope, severe arrhythmia, structural heart disease (to be ruled out).]

Current status: Under evaluation.

Lin Ye only glanced at it.

He pressed that line down.

The ink on the record sheet for "fainting after exercise" was still wet.

The electrocardiogram paper was placed on the left side of the recorder.

The boy's hand was still pressed against his chest.

Lu Yifan's words, "I'll be fine after sitting for a while," still lingered at the foot of the bed.

Qin Hai took off his stethoscope.

The blood collection tubes had already been laid out on the tray by the nurse, and the monitoring lines were looped around the bed rail. Qin Hai's voice fell amidst these movements.

"Draw blood."

"Complete blood count, electrolytes plus calcium and magnesium, cardiac markers, liver and kidney function tests."

"Connect him to a cardiac monitor and don't let him sit in the corridor anymore."

"Contact the cardiology department, and stay informed about the admission procedures for pediatrics and minors."

The teacher suddenly looked up.

"Cardiology?"

His voice changed suddenly.

"Isn't it a pediatric ward?"

Qin Hai handed the electrocardiogram chart to Lin Ye.

"Let's see if it's life-threatening first."

The teacher opened his mouth and pressed the tip of his tongue against his teeth.

He swallowed the words back.

The night shift nurse has already attached the monitoring tape.

The screen lights up.

Heart rate 122.

Keep the rhythm in sync.

However, being well-equipped does not guarantee safety.

Lin Ye walked to the teacher's side.

"Where are the parents?"

The teacher then remembered and hurriedly dialed the phone.

No one answered the first time.

The phone rang for a long time the second time.

The teacher's forehead was sweating.

"His mother should be on her way to work."

Qin Hai's gaze swept across the messages in the class group chat.

"Hit again."

"Don't just send messages."

The teacher nodded.

On my phone screen, messages from the class group chat were still popping up.

How is Lu Yifan?

Should the teacher notify the grade head?

Is it heatstroke?

Should we let the other students go back to the classroom first?

Messages were crammed onto the screen.

The teacher's hands became even more confused as she watched.

Lin Ye reached out and pressed down on the edge of his phone.

"Strike the parents first."

"We'll talk about it in the group later."

The teacher swallowed.

The call went through this time.

The first sound coming from the receiver was the sound of traffic, followed quickly by a woman's voice.

"Teacher Wang? What's wrong with Yifan?"

The teacher looked at Lin Ye.

Lin Ye did not speak for him.

Qin Hai didn't have it either.

The teacher held the phone close to her ear.

"He had chest pain after his 800-meter morning run and just felt dizzy. He's in the emergency room at the First Municipal Hospital, where doctors are examining him."

Only half a second of chaotic car noise remained in the receiver.

"Did you faint?"

The woman's voice suddenly became shrill, then quickly subsided.

"I'm coming right away."

Lin Ye added the key points.

"I am Lin Ye from the emergency room."

"The child is conscious now, but the chest pain and fainting after exercise cannot be treated as just running fatigue. We have already done an electrocardiogram, connected the child to cardiac monitoring, and are contacting the cardiology and pediatrics departments."

The breathing on the other end of the phone became erratic.

"Cardiology?"

The teacher lowered her head, her fingers still gripping the edge of her phone case.

Lin Ye glanced at Lu Yifan on the bed.

The boy stared at the ceiling, his eyelashes still wet.

When he heard the words "cardiology", his lips pursed even tighter.

Lin Ye lowered his voice.

"Now we need to ask about a few medical histories."

"Did he experience chest pain, heart palpitations, fainting, or blurred vision when running or playing sports?"

The woman on the other end of the phone did not answer immediately.

First, a horn blared from the receiver, followed by the screech of brakes. The woman took a breath and didn't answer.

A few seconds later, the woman's voice came out again.

He said it once.

"I thought it was low blood sugar."

Lin Ye's pen stopped on the notepad.

Has anyone in your family suddenly collapsed, died suddenly, or suffered a heart attack of unknown cause when they were young?

Lu Yifan turned his head.

The woman on the other end of the phone remained silent.

Only breathing.

It's getting heavier and heavier.

Lin Ye did not urge him.

Qin Hai didn't urge him.

In the emergency room, the monitor beeped.

Lu Yifan's heart rate was still around 120.

All that could be heard through the receiver were the distant sounds of traffic and the monitor tapping on the bedside.

She took a breath through the receiver, but it wasn't steady.

"His dad..."

She paused for a moment.

"His father collapsed while playing basketball when he was thirty-five years old."

The teacher's knuckles, which were gripping the phone, turned completely white.

The phone almost slipped from my hand.

Lu Yifan's eyes widened.

"mom?"

The breathing on the other end of the phone suddenly became erratic.

She had barely uttered the first half of her sentence when the sound of traffic drowned out the second half.

"Yifan, don't be afraid, Mom will be there soon."

Qin Hai reached out and flattened the two electrocardiogram sheets again.

The emergency light shone on the paper, and black waveforms lined up one by one.

He looked toward the nurses' station.

"The cardiology department is following up again."

"I've already taken the electrocardiogram. Tell them that the patient experienced chest pain and fainting after exercise, and that the electrocardiogram was abnormal."

"There is a family history of sudden death during exercise when young."

The night shift nurse picked up the phone.

The landline buttons were being pressed repeatedly.

Lin Ye lowered his head and added the last line to the record sheet.

My father died suddenly during exercise at the age of thirty-five.

As the pen touched the paper, Lu Yifan's monitor suddenly beeped three times.

It's not very long.

But it was enough to make several people by the bed look up at the same time.

On the screen, a series of irregular waveforms just slid by.

Qin Hai lowered his voice.

"Bring the defibrillator over."

"Don't let him leave his guardianship yet."