International Space Station, American module.

Steven had just finished his workout and ran for an hour on a combined weighted external resistance treadmill and did some other resistance training.

In the microgravity environment, it is easy to cause muscle atrophy and bone calcium loss, and this phenomenon will be more serious if you cannot maintain a certain amount of physical exercise.

After returning to Earth, they will not be able to walk because of muscle atrophy, and they will be prone to fractures due to osteoporosis.

Steven wiped his sweat and swam his lithe body back to the living compartment, where various utensils hung from the bulkhead.

He checked the air pressure in the cabin, there was no abnormality, not long ago, there was a leak in the Russian cabin, losing 220g of air per day, it took a month for the magical Russians to finally find the leak, a breach of only 1 millimeter, they blocked it with tape, and then said that they could sit back and relax.

If it was Steven, he would definitely do a spacewalk and do an extravehicular welding block, otherwise it would be difficult to sleep peacefully.

His partner, David Hawley, is also looking at the Earth in the turret observation module, and he loves photography, always likes to take pictures inside and outside the cabin, and then select some high-quality photos to post on Facebook.

David Hawley was in love, and he just wanted to use these pictures to attract the girl.

Looking from the inside of the cabin, there is no doubt that the dome cabin, the turret, with seven observation modules, is the best choice.

Steven opened his laptop and began to select the photos, which were taken by the camera outside the space station, and he promised his daughter to accumulate photos of different regions of the earth, and the photos must be taken by the external camera, so that they will not be separated by a transparent window.

At this time, Steven is the most relaxed, completing a day's scientific tasks and doing some personal things for his daughter, which he takes pride.

When it's time to make a video call with my wife, the ISS has three communications satellites that can connect to the Internet, not only to communicate with the ground control center in Houston, but also to video call with family, check the web, browse the news, tweet and Facebook.

"Honey, I just came back from the supermarket, you see, my daughter is going to fill the refrigerator now, it's full of fruits you like to eat, I told her to wait, there are still twenty days, don't worry, she doesn't listen at all." While the wife is busy, she keeps the camera pointed at her.

Steven's wife, a teacher at an elementary school in Houston, was cooking dinner with steaks, salads, juices on the table.

"Honey, in twenty days, we can meet."

"We're waiting for you, my dear, it's like a year, I saw the news on NASA's official website, twenty days later, a Dragon spacecraft will be launched from the Kennedy Space Center, and you will complete the rotation."

"Daddy, Daddy!" The voice of an eight-year-old daughter.

"Slow down, baby, what are you doing?" Steven saw the funny daughter, wearing film gloves, and her face, hands, and clothes were covered with cheese-like things.

"I'm making a salad, and when you come back, I'm going to make a plate of fruit salad for you." The daughter was so excited that she danced.

"She's learning to make fruit salad, you look at her face, that's what she's doing for you." The wife took a wet towel and carefully dried her daughter's flowery face.

"Dad, remember to save a set of photos for me, I promised my classmates, one for each person, and your signature, I must be a person who keeps my word." The daughter reminds every time.

"I'm picking, and I'll send it to your email in a few days." Steven has picked about the same.

"She prepared a speech topic - looking at the earth from space, she speaks to our cat every day, and now she will send your photos as material." The wife touched her daughter's face.

"Thank you Dad! Let's talk, I'll go to my room and hide now, and I'll give you fifteen minutes. The daughter said goodbye to Steven and hid in her room.

The wife is facing the camera: "Honey, really, I miss you and worry about you. Every day we use our telescopes to look out the window at the sky, hoping that you will fly over our heads, and Linker has written a table to mark the time you have passed with a red pen, and you- are you okay?. ”

"Good work, dear, I'm fine, are you okay?"

"Well, I'm fine, Lin Keer wants to learn to surf, but I won't, she's waiting for you to come back."

The door opened secretly, and Lin Keer's eyes looked at her parents who were video chatting through the crack in the door.

---

The Johnson Aviation Center, the administrative office of Building One, has been lit up.

Members of the medical team and specially appointed experts from all over the country were engaged in heated discussions.

The discussion lasted from 3 p.m. to 7 p.m. and was not over.

"Our core question has been clarified, the cause of Steven's heart rate slowing is unknown, will this unknown cause affect his return to Earth? Once you are able to return to the ground, everything is well resolved. Corinth figured it out.

"That's right, you've found the focus, and I insist on my opinion, and I can't rule out tumors in the brain stem of the skull, or other lesions."

"Ladies and gentlemen, not long ago I met a patient in my 70s who had a brain stem bulbar tumor with a slowed heart rate and breathing as the first symptom."

"What I mean by this is that if the lesion affects the heart beat center, it can cause the heart rate to slow down, and if the lesion affects the respiratory center, it can cause the breathing to slow down."

"I suspect that some kind of lesion is affecting Steven's heartbeat center, the probability is very low, one in a thousand, but we can't gamble, and I suggest not returning to Earth until we figure it out. If it is a malformation of blood vessels, the spacecraft enters the atmosphere, falls at high speed, ruptures blood vessels, and is certain to die. ”

Johanneson stood up and expressed his point in an agitated tone.

Dr. Eugene also stood up: "Judging from the current color ultrasound examination results, there is no problem with the heart, and the blood sample test brought back last time did not find any abnormalities, but I want to contact Steven and personally guide him to do the heart color ultrasound again, the human health status is dynamic, and the previous examination cannot explain everything." ”

"Wait for the meeting to end, let's connect with Steven and redo the heart color ultrasound."

Collins agreed with Dr. Eugene that the doctors in the medical team were not a little different from the Johns Hopkins professor of cardiovascular medicine in terms of their ability to identify color ultrasound images.

"At the same time, I supported Professor Johannesen, and without understanding the reason, I rushed back to the sea, no doubt gambling with Steven's life." Eugene added, in a heavy tone.

Other experts also agreed with the two professors' words that whether it is a cardiac or intracranial disease, it is necessary to figure out the cause and assess the risk of returning.

"Our opinion is now unanimous and further investigation is necessary to figure out the cause and rule out some fatal diseases." Collins concluded.

Johanneson was straightforward: "Yes, it is not practical to have a cerebral angiogram and an intracranial CT or MRI, but as long as there is a cerebral angiogram, I can at least do a basic risk assessment." ”

"We don't have iodinated contrast in our medicine cabinet, and the station's simple X-ray machine can't trust digital subtraction angiography." Collins knows all about the medicine box in the American module of the ISS.

He looked at the Russian doctor in the medical team, and the Russian doctor also said that he could not help: "Unfortunately, although we have 18 medicine boxes, we do not have iodine contrast agents. ”

The Russians sent an up-to-date medicine manual, and Corinth flipped through it.

As early as 50 years ago, when human beings first marched into space, astronauts had the habit of carrying a medicine box to space, but what should be contained in this small medicine box was not mature at that time.

With the increase in the number of space flights and the advancement of aerospace medical knowledge, this list of drugs is becoming more and more mature.

The International Space Station (ISS) has a large stockpile of medicines to cope with astronauts' health accidents, and the medical team has compiled a list of drug names based on a list of injuries and illnesses that may occur while staying on the space station.

In addition to medications, the space station has a number of medical instruments: a small electrocardiogram measuring machine, a pulse meter, a blood pressure monitor, a megaphone stethoscope, and basic cardiopulmonary resuscitation equipment.

Spacecraft that travel between the space station and the ground only once every two or three months.

If the astronaut has the medicine that he urgently needs, there is no medicine box at this time.

Ground crews are to be prepared in the quantities they may need to send the spacecraft into space.

Due to the limitation of the load of the spacecraft, the drugs transported should be carefully selected, and the broad-spectrum mature drugs should be selected as much as possible.

The American module of the International Space Station has nine medicine boxes, but there is no iodinated contrast agent, because no one would have thought that astronauts in the sky would have to perform angiography examinations.

Collins rubbed his temples, "If that's the case—I'll have to report it, it's going to need to schedule a spaceship launch in advance, deliver the medicines and instruments, and send Susan up." ”

Collins decided that it had to be escalated, and that the issue was no longer something that could be solved by the medical team, and that it should be up to the head of NASA to decide.

The astronauts received very limited medical training, all basic treatment and first aid, and to complete a cerebral angiogram, which had to be done by a more professional person, this person was Susan.

She is not only an astronaut, but also a surgeon with professional medical literacy and can perform some basic surgeries independently.

Collins raised his head, and the soreness in his cervical spine made him feel heavy: "What else do you have to say, now that the situation is going to escalate, if you have to do this?" Arrange a special flight to get Susan and medicine to the space station. ”

"For one launch, the minimum cost is more than $100 million based on the load of two people."

"This is Musk's price, and in the past, the average cost of each launch in the United States was $450 million."

Two engineers who attended the meeting reminded everyone if there was a better way.

"This is Mr. Director's math problem, and our problem is, if you make the risk of one in a thousand become zero."

Johanneson said solemnly that considering the cost of money in the face of human life is contempt for life.

The words of the two engineers provoked the hostility of all the doctors, and they immediately shut up, and they showed up in the room just to answer any questions the doctors might have about the engineering aspects of the space station.

"That's right, this question is left to Mr. Jimbasa, maybe he can lower the price with Mr. Musk."

"I'm going to prepare a report tonight, report to the Chief Medical Officer and Mr. Director of the Washington headquarters, and ask for an additional courier to send Susan and the medicine for us, gentlemen, sorry, hard work, let's go to the ground control center immediately, connect with Steven, and conduct a color ultrasound inspection again, and finally, we have to work together to make a detailed plan, such as the list of drugs and equipment for the delivery, whether Susan will have to carry out intensive training, and dinner can only be solved with fast food at work, I'm very sorry." Collins ended the meeting and immediately led everyone to another building, the ground control center.

There were eight staff members busy, all staring at the screen.

The ground control center implements a shift system, with one shift of nine hours, to ensure that seven or eight staff members are on duty 24 hours a day.

"Emergency Medical Connection, Connect Steven, Now!" Collins told the shift leader.

"Wired Steven!" The team leader commanded loudly.

The staff in charge of communications immediately connected to the video system of the station.

After a few calls, Steven's face appeared on the screen.

"Hi everyone, I'm Steven, I'm fine, what's going on, Collins, your team seems to be there?" Steven greets.

Collins kept smiling: "Don't worry, we just had a meeting to slow your heart rate, and now Dr. Eugene needs to guide you to do a new color ultrasound, do you need Davy Hawley's assistance?" ”

"No, no, I can do it myself, I don't feel any discomfort, today I finished an hour of running, I don't think there's anything wrong with me, either you're wrong, or the instrument is wrong, in short, it's not my fault."

Steven swam his body and began to open a storage box and pull out the ultrasound machine from inside.

"From now on, you're going to stop moving." Dr. Eugene admonished Steven.

The cause is not found, in case it is a problem of the heart muscle, exercise increases the load on the heart, which will cause arrhythmia, and the consequences are unimaginable.

"Johns Hopkins, Dr. Eugene, Cardiovascular Medicine Specialist." Collins introduced.

Steven straightened the wires and turned on the switch: "Although I strongly disagree with your words, I will follow the proposed advice, because you are a doctor, can you start?" ”

"That's it." The staff in charge of communication adjusts the screen, and the color ultrasound image of the space station is synchronized with the screen in front of them.

"It's okay, you can do the color ultrasound of the heart again according to the steps now." Corinthian Order.

Dr. Eugene and the others gathered in front of the communication screen, looking at the frame of the color ultrasound image.

Left and right ventricles, left and right atrium, individual valves, aorta, vena cava, pulmonary artery, pulmonary vein-

Dr. Eugene carefully looked at the pulsating heart ultrasound images, and he asked Steven to repeat them several times.

No questions asked!

"Do you feel sick? For example, chest discomfort, lack of oxygen, general fatigue, lack of exercise? It's about your return. Dr. Eugene is not yet at ease.

"No, I don't feel any discomfort." Steven is optimistic and doesn't think there's something wrong with him.

"Headache and dizziness, muscle incoordination, anything is wrong with one place?" Johanneson asked.

"No, I'd like to challenge Tyson if I could."

"Okay, rest well, feel free to contact us if you have any questions."

Dr. Eugene couldn't see anything wrong with the ultrasound.

You can only wait for the next check.