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

The pulmonologist hovered the mouse over the hazy lung image. The rheumatologist on duty had just entered the red zone when he heard this, walked straight to the screen, bent down, and looked at it for two seconds.

As she flipped through the images on the screen, her lungs seemed shrouded in a grayish-white fog. The further she looked, the more her brows furrowed.

"How much blood are you coughing up now?"

The pulmonologist showed her the sputum from the suction bottle: "It wasn't a gush, but it had dark red, frothy sputum. Oxygenation was poor. The hemoglobin level was 96 at the other hospital, so you'll need to have it retested after you get here. The original urine test results are here."

Lin Ye handed the medical record folder forward slightly.

The urinalysis, kidney function tests, and last month's physical examination report were all covered with sticky notes peeking out from the corners of the pages, making them easily visible to rheumatologists.

She first looked at the urinalysis, then the creatinine, and finally flipped to last month's physical examination report, pausing her finger on the date.

"It didn't gradually deteriorate from a pre-existing chronic kidney disease." She put the paper back. "Where are your family members?"

The elderly man's wife stood guard at the entrance to the red zone, her phone pressed to her ear, seemingly talking to her son. As she listened, she glanced at the emergency bed, her eyes red-rimmed, yet she dared not cry out loud.

Nurse Zhu pulled her half a step inside: "When the doctor asks a couple of questions about your medical history, answer with what you can confirm, don't guess."

She quickly put her phone down: "My son is on his way, let me speak first."

The rheumatologist looked at her and asked, "Besides the fever and cough, have you had any nosebleeds, mouth ulcers, rashes, or joint pain these past few days? When did your urine start becoming darker?"

The old man's wife paused for a moment, then lowered her head and thought for a long time.

"His nose... He's been blowing his nose in the mornings for the past two days, and there's a little blood on the tissue. He said it's because of the dry weather, so I didn't think much of it. He's always had joint pain, saying his knees are sore, but I thought it was because he's old. His urine is dark in color; I noticed it last night when I emptied the bedpan. It looks like strong tea, and I told him to drink more water."

"Have you been taking anticoagulants or antiplatelet drugs such as aspirin, warfarin, or rivaroxaban?"

"Nothing special about Hua." She hurriedly rummaged through her medicine bag. "Just blood pressure medication and a cholesterol-lowering drug. The doctors at the Second Hospital also asked about the medications, and I showed them to them."

Lin Ye took the medicine bag, copied the name of the medicine box and dosage into the record, and added "The family denies a history of anticoagulant medication, and the medicine bag contains antihypertensive and lipid-lowering drugs." When he wrote "blood in nasal mucus," he paused and left a separate line next to it.

Beside the bed, the old man began to stir again, his fingers gripping the sheet. The nurse had just secured the second intravenous line, and before the tape was even firmly applied, his hand twitched, nearly lifting the needle.

Nurse Zhu reacted quickly, pressing down on his wrist: "Sir, don't grab it, the needle has just been inserted."

The old man opened his eyes a crack, as if he had heard something, but also as if he hadn't understood. His lips moved twice under the oxygen mask, but he didn't make a sound.

The oxygen saturation level on the monitor kept fluctuating between 88 and 90.

The pulmonologist glanced at the readings: "Prepare for high-flow humidified oxygen therapy. If the patient's consciousness deteriorates further or oxygenation fails to improve, the anesthesiology department needs to be informed in advance. Don't wait until things are really unbearable before calling for help."

Qin Hai nodded: "I'll have someone alert the anesthesiology department."

He turned to the nurses next to the red zone and instructed them, "The anesthesiologist on duty should let them know that there's someone in the red zone with low oxygen, hemoptysis, and poor consciousness who may need an airway assessment."

The nurse went to make a phone call. On the other side of the treatment tray, several blood collection tubes and blood culture bottles were already labeled, with coagulation, kidney function retest, blood type, crossmatch, and immune-related items placed separately, and the wristband information that had just been verified placed on top.

The rheumatologist glanced at the treatment panel: "Add anti-GBM antibody, ANCA, complement, and antinuclear antibody profiles. Don't forget the infection test; continue with blood culture, sputum culture, and respiratory pathogen screening. We can't rule out infection yet."

The respiratory physician added, "I agree. Don't push him back down the path of ordinary pneumonia, and don't miss any infection screenings."

The lab called first.

Nurse Zhu listened for a few minutes, her face darkening. She handed the receiver to Qin Hai: "The patient we just sent to the red zone has a hemoglobin level of 88."

Ninety-six in the outer courtyard, eighty-eight in the inner courtyard.

The old man's wife stood by the door, not understanding what the number meant, but she saw Qin Hai take the receiver and remain silent. She was about to go inside when Nurse Zhu stopped her, saying, "Don't come in yet."

The pulmonologist muttered a curse under his breath and moved the suction device closer to the head of the bed: "The hemoptysis hasn't stopped."

The rheumatologist took out his phone and dialed the second-line rheumatology and immunology department. The call was connected.

"Red zone, 66-year-old male. Hypoxia, dark red frothy sputum, progressively decreasing hemoglobin, creatinine 268, positive for occult blood and protein in urine, CT scan shows diffuse ground-glass opacities in both lungs. Respiratory and renal endoscopic findings are at the bedside."

There was silence on the other end of the phone.

She listened for a few seconds, then turned to Qin Hai and the pulmonologist: "Second-line patients should be admitted as critically ill patients suspected of having pulmonary-renal syndrome, and priority should be given to coordinating respiratory intensive care beds. Don't waste time in the emergency room until the antibody report comes back."

Qin Hai pressed the bedside card back into place: "Then transfer to the respiratory intensive care unit. Collect the necessary specimens first, and reassess oxygenation and consciousness before transport."

The old man's wife finally couldn't hold back any longer: "Doctor, does he need to be moved to the intensive care unit?"

The pulmonologist removed his stethoscope and walked to the door. Her eyes were fixed on the bed, so the doctor turned slightly to the side so she could see that the person was still lying there, and a nurse was standing beside her.

"We need to go to a place where we can keep a close eye on things," he said. "It's not a situation where you can just get a few IV drips and some anti-inflammatory drugs and then put them in the emergency room for observation. If their oxygen levels aren't high enough, there's a risk of bleeding in their lungs, and their kidney function is deteriorating rapidly. We need to go to the intensive care unit so we can keep a close eye on their blood oxygen levels, hemoptysis, urine output, and changes in lab results."

"Will they need to intubate?"

"That's possible." The pulmonologist glanced at the high-flow oxygen machine by the bedside. "Let's try high-flow oxygen therapy for now and see how it goes. If the patient's consciousness deteriorates further, oxygenation doesn't improve, or if hemoptysis blocks the airway, we'll need to call in the anesthesiology and intensive care units to assess intubation."

Before the call ended, her son's voice came through the receiver: "Mom? Mom, give the phone to the doctor, I'm almost there."

She quickly handed over the phone, nearly knocking over the medicine bag in her arms in her haste: "Doctor, my son wants to ask about his condition."

Qin Hai took the phone, not holding it too close to his ear: "This is Qin Hai from the emergency room. Your father is critically ill and is undergoing resuscitation and assessment in the red zone, preparing to be transferred to the respiratory intensive care unit. When you arrive at the hospital, come directly to the entrance of the emergency red zone. Don't make this call while driving. We'll discuss the specific situation on-site."

The voice on the other end of the phone suddenly became anxious, as if trying to ask more questions.

Qin Hai interrupted him directly: "Make sure you get to the hospital safely first. If something happens to you, no one will sign the papers for your father."

After saying that, he handed the phone back.

She paused for a moment, then nodded quickly: "Yes, yes, don't talk on the phone while driving."

The elderly man was put on a high-flow nasal cannula and his oxygen mask was removed. His face was still ashen, but his oxygen saturation slowly climbed to 91 and finally stopped at 92.

The pulmonologist glanced at it and said, "That's all for now. Don't be fooled by 'Ninety-Two.' Keep an eye on consciousness, hemoptysis, and hemoglobin levels."

The rheumatologist stood at the foot of the bed flipping through the test request forms. When he saw the section on anti-GBM antibodies, he circled it heavily with his pen.

"Call me immediately as soon as this report is released, no matter what time it is."

The nurse nodded: "I understand."

Twenty minutes later, the old woman's son arrived. He was covered in sweat, and the back of his short-sleeved shirt was soaked. He glanced at his mother first, then looked at the emergency bed, his phone still lit up, and he remained silent for a long time.

When the old man's wife saw her son, her body went limp, and she slid down the wall a little while holding onto it.

Nurse Zhu helped her up: "Don't sit on the ground, there's a chair over there."

The son helped his mother to a chair and looked at the doctor: "I'll sign the papers. Doctor, you can treat him however you want. My dad could walk on his own this morning, we can't just leave him like this..."

The second half of the sentence got stuck in my throat.

The respiratory physician placed the critical condition notice and related information about transferring to the intensive care unit in front of him.

"Please listen carefully before signing. We are currently considering simultaneous lung and kidney problems. The cause is still under investigation; it could be an infection or an immune-related disease. You will be admitted to the respiratory intensive care unit for oxygen therapy, monitoring, blood gas analysis, urine output, hemoglobin levels, and kidney function. If stronger respiratory support is needed, or if the rheumatology and immunology department decides to administer immunotherapy, we will communicate with you further."

The son gripped the pen tightly, and before signing, he glanced up at his father on the bed.

"He's most afraid of being hospitalized." He lowered his voice. "Last year during his physical exam, he complained about the hassle of blood tests, saying he was perfectly healthy."

The old man's wife sat in a chair, covering her mouth, tears streaming down her face through her fingers.

Lin Ye completed the signing process, including the date of signature, notification to the doctor, and details of the family relationship. The transport bed had already been moved to the entrance of the red zone, and the respiratory physician and nurses rechecked the oxygen cylinder pressure and monitor battery level, confirming that the suction device was included with the vehicle.

Before the transfer, Nurse Zhu pulled out the intake and output sheet from the foot of the bed and clipped it into the transfer data: "Don't forget this, you need to keep recording it for the respiratory critical care patients later."

After the bed rails were secured, the elderly man was wheeled towards the elevator. His son followed beside him, one hand holding onto the edge of the cart, the other holding the pen he had just used to sign. Only when they reached the elevator did he remember to return the pen to the nurse.

Before the elevator doors closed, the rheumatologist turned to the pulmonologist and said, "Before the reports on the anti-GBM and ANCA tests, call me immediately if there are any changes. Don't wait until the morning shift handover."

The pulmonologist nodded: "I'll talk to the second-line doctor."

The elevator doors slowly closed.

A space suddenly cleared out in the red zone, with bits of adhesive tape still on the ground. Nurse Zhu bent down, picked them up, and threw them into the yellow medical waste bin.

Lin Ye returned to the nurses' station and completed the transfer record for the emergency room. Next to the last column, "Preliminary Diagnosis," he paused for a few seconds, then wrote down the specialist consultation opinion from earlier:

Pulmonary-renal syndrome to be ruled out; diffuse alveolar hemorrhage possible; severe pneumonia and infectious causes to be ruled out.

After I finished writing and put down my pen, I realized that my wrist was a little sore.

Just as Lin Ye closed his medical record folder, a young man in a black T-shirt, holding a thermometer, hesitated and took two steps toward the triage desk from the waiting chair outside.

"Nurse, I just accompanied my dad to a CT scan." His voice was hoarse, and the edge of his mask billowed as he breathed. "I also have a fever now, 38.7 degrees Celsius."

Nurse Zhu looked up at him, then at the CT scan report in his hand.

"Don't go in yet." She put down the registration pen in her hand. "Sit back in that row of chairs on the outside and make sure your mask is on properly."