Isekai Surgeon
Chapter 7

Author: Honda Tsumugi
Source: Xant & Minions

– Index –

「The drop of the World Tree? Is that… really necessary as a medicine?」 「Yes, it is. There are no other alternatives for it.」

I was going to make an incision into the body. If the operation took a long time, the likelihood of bacterial infections would increase. Furthermore, incisions in the chest, particularly ones near the heart, would become life-threatening if infected. The skin was an essential barrier against bacterial infections, and opening it created a prime opportunity for infections to take hold.

「It seems that the drop of the World Tree can only be obtained from the seventh floor and above. On top of that, we will need to use pharmaceutical magic there to process it immediately.」

「Yeah, and it seems to only be effective for a few hours after harvesting.」

That was why when we had gathered it in the past, Reina immediately teleported us back to the other side of the continent. As soon as we arrived, the client was made to drink it at once. I didn’t know what the effect was, but the client’s condition improved.

Actually, I’d realized it was a disease called beriberi, which was caused by vitamin B1 deficiency, so I added some vitamin B1 into the drop of the World Tree before giving it to the client. I also casually told the client’s servants that his diet was imbalanced. The noble, who misunderstood that his “curse” was cured, had given us a large reward for it. It was somewhat of a scam, but it still saved him.

At the time, I had put aside some of the drop of the World Tree and analyzed it, discovering that antibiotics were part of the components mixed in it. I’d also found that it was true that it deteriorated quickly, especially when exposed to ultraviolet rays. There may be a difference if it was placed in a container that could block UV light, but it was definitely not a medication that could be preserved for long.

「I can use pharmaceutical magic, but I don’t think Reina and I can climb up to the seventh floor of the World Tree alone.」

It was possible to climb the tree with just the two of us, but I would be exhausted by the time I reached the drop of the World Tree, and I didn’t know if Reina could still Teleport afterwards. Of course, if we had Ceder and Brad, or similarly strong adventurers, we would be fine. However, were there any adventurers in Yggdrasil of their caliber?

「I understand. I’ll go with you. Unfortunately, there’s no one other than Neumann who can be our vanguard.」

Ron surprised us with this information. Neumann was apparently one of the top adventurers in Yggdrasil. Reina’s load would probably be reduced if Ron came along, and I knew I wouldn’t have to do as much work if Neumann came, so I agreed to his proposal.

The question now was when to go. There was no established method to preserve the drop of the World Tree. So far, it was only possible to extend its potency from a few hours to two or three days. We needed to pick it on the day of the surgery, use pharmaceutical magic on site, and then immediately teleport back to perform the surgery.

「I think we can go for it when all the other goods are ready…」

Failure was not an option. I repeated the simulation I had in my head. Even then, I didn’t know what could happen and what I really needed until I got there, so I couldn’t take my mind off of it. It wasn’t something one could practice with someone.

After that meeting, I prepared myself as much as I could for various situations until the instruments were ready. It was a great help when Miria volunteered herself to be my surgical assistant. Reina had to use her magic continuously to keep the patient unconscious. She might not be able to concentrate on the surgery itself. In short, it was helpful to have an assistant while she was busy being an anesthesiologist. I explained the things I needed help with to Miria. When performing surgery, they had to wear masks, gloves, caps, and gowns in order to prevent bacterial infections as much as possible. They would have to get used to the discomfort and remember to not touch anything other than what we knew was sterile. For example, if one of them happened to touch their hair, the bacteria from her hair would invade the wound. Bacteria were invisible to the naked eye, but they were everywhere.

「I don’t want to wear gloves made out of slime jelly…」

「You need to get used to it.」

Magma slime jellies were luxury items. They were difficult to hunt and were rarely used on a daily basis. However, it couldn’t be helped since they were needed for surgery. I didn’t have the confidence to properly sterilize them without the heat resistance.

I was going to use the “autoclave” technique for sterilization. This technology was also used in Japan, where sterilization was performed using high temperature steam. I couldn’t measure the temperature and pressure very well, but I think it was easy to understand if one imagined putting the instruments into a pressure cooker and boiled them. By sterilizing them under pressure at 121 degrees Celsius for 20 minutes, most of the bacteria would die. Since there were few antibiotics in this world, I didn’t think there would be bacteria with resistances, nor would I have to do it with extreme precision. However, Japan’s medical facilities gave their best because we didn’t know what was out there, and I had learned and grown from their knowledge. I was worried since I didn’t know what was out there, so it was only natural to be cautious. This was a human’s life we were dealing with, after all.

Most of the equipment was ready after a few days of preparation. The renovations for the operating theater were also almost finished. Last of all, Reina’s long-awaited bath was also finally completed.

「Now, I don’t have to go to public baths anymore.」

The walls and floors of the finished bathing room were coated with magma slime jelly, making it completely waterproof. Expensive magic tools were used, such as the water magic tool in the bathtub and wind magic tools for ventilation. Because of these, we couldn’t afford the fire magic tool used to heat the bath water, so in the end we heated the water with Reina’s magic. Still, being able to use magic was pretty convenient. The only problem was the possibility of being unable to use the bath whenever Reina was in a foul mood.

I’d hoped that we could add an extension to enter the bath and toilet without having to go outside, but it wasn’t possible for now.

「Please tell me if there are any problems when you try it out.」


I decided to let Reina have the first bath. Currently, I was worried about any problems with the room that was still being renovated into the operating theater. After waiting for an hour, Reina came out. One look at her face could tell anyone that there were no problems.

「Everything was great.」

「Thank you. I wonder if I should enter too.」

I didn’t hate baths. I wasn’t good with long ones, but I felt happy when a bath slowly warmed me up. The bathroom was spacious and comfortable. There wasn’t a shower, so I had to wash myself with hot water from the bathtub. Actually, I didn’t have to wash myself properly before entering the tub since I could just use “Wash” to clean myself in this world. People here who couldn’t use magic apparently had magic applied on them before taking a bath.

「How’s the hot water?」

「Mmm, it’s just right.」

Reina’s voice came from outside the bath. She was the one who used fire magic to heat the water in the bathtub. I guessed Reina would spend most of her time in the bath from now on, and without her, I couldn’t take a bath. I was thinking about learning some black magic when I decided to step out because I was getting dizzy from not realizing a long time had passed.

「Ah~ that was a good bath. It’s good to be able to warm up before going to bed.」

「I know, right? That’s why I had absolutely wanted it.」

In addition, there were no particular defects in the bathroom that was full of the same features used in the operating theater. If this was the case, the operating theater that was still under construction would also become fully functional. I wondered if I could use that building again after Amanda’s surgery. The building was mostly thanks to Ron’s abundant wealth after selling his staff, and we wouldn’t be able to buy such a fine building with the money we had.

「Speaking of which, to whom did he sell Sunrise to?」

Reina muttered. Was it possible she wanted the staff as well?

A few days later, we received a report that the renovations were almost completed, so we carried our equipment into the operating theater. It was originally a residence over some sort of company, so it had the kitchen on the second floor. I lit a fire on the hearth, and there I installed the “autoclave”, a special tool used for sterilization. I poured some clean water into it and made sure it could boil properly under pressure.

「The adjusted saline water goes here… oh, put those medicines on this shelf.」

I was preparing the medications and drips that were going to be used in the surgery. The drips were made by adding various chemicals and salt in sterilized distilled water, and adjusting their concentrations in the solution. It was poured into a special container that had been manufactured to administer the IV drip easily.

Surgical gowns, caps, masks, gloves, and many of the surgical instruments needed to be sterilized, so it seemed the autoclave needed to continuously operate until the day of the operation. Furthermore, it was necessary to pay attention to where the sterilized equipment was stored, so each of them was placed in a sealed container. I was the one who did this first, because I had to ensure it was done while preserving the sterility. Miria and Neumann, who were observing, began to help bit by bit. Before I knew it, they had become like my assistants, and I really appreciated their help.

「Is this enough?」

I had prepared so many items that I didn’t know what else to prepare anymore. There were a lot of spares, since I didn’t know what surprises could happen. Once something became unsterile, it could not be used until it was re-sterilized.

「Are you all set? Now the only thing left is to go get the drop of the World Tree.」

Before I’d noticed, Ron had come to see how things were going. I heard there was a considerable amount of work for Guild Masters, but it seemed it was relatively easy for him to visit since we were right next to the guild.

「Not yet. There’s still a lot of work to do.」


「It’s persuading Mrs. Amanda. For someone who has that amount of magic power, even if it was Reina, she might resist her ‘Coma’ spell too.」

Obviously, the patient’s consent was necessary for an operation, even disregarding the fact that it was a different world with less established regulations. It was a crime if one abducted and knocked out a person without permission and then performed surgery on them. It didn’t matter if it wasn’t committed by the person directly or even the fact that this was a different world.

「You’re right…」

「This is why I have no choice but to ask Mr. Ron for help.」

I didn’t know if he truly trusted me when we had only just met. I’d heard the medications I prescribed had improved her anginal symptoms a bit. I went to examine her a few times, and it seemed to me that she was feeling a little better. The medication was based on nitroglycerine, which made the blood vessels easier to dilate, and compounded Hikarabidake (TL note: poisonous mushroom), which increased urine production and lowered the load on the heart. I didn’t think it was necessary to add in the Gigantoad’s parotid gland, but I also used pharmaceutical magic to compound herbs that lowered blood pressure with milk from a cow monster that had properties of protecting the mucous lining of the stomach.

All of these medicines were for diseases that couldn’t be simply cured using a healing spell. Amanda may trust me, since the medication had some effect. however, even if she trusted me, she still had the choice to opt out of the surgery, even if she understood there was no other way to cure her.

What if Amanda refused the surgery? We told Ron that we should get Amanda’s consent first. If she didn’t agree to it, all our preparations for this operation were for naught. However, Ron said that we should leave persuading Amanda until the last minute. Therefore, even if the preparations for the operation were in vain, the expenses were covered.

「Eh? Why?」

「No, I understand, Mr Ron. Let’s do it last.」

Ron didn’t give us a reason. Reina seemed to have not understood, but I knew what it was. I understood because I had experienced many patients’ families and relatives giving this same reaction.

Ron’s heart may have started to resign a bit, and he might have been feeling guilty for this. When Amanda had accepted her imminent death, Ron didn’t know what to do and was anxious. Therefore, he had wanted to delay it as long as possible. However, all I could do in the end was treat Amanda.

「Tomorrow, let’s talk to Mrs. Amanda together.」

「Yes, I understand.」

When all was said and done, Ron was a Guild Master and an ex-rank S adventurer in Yggdrasil’s Adventurer Guild. He couldn’t run away from this.


「Alright, I believe in you.」

Amanda said to Ron, not me. Her chest pain seemed to have subsided a fair amount, but her face wasn’t showing the desire to survive, but some other feelings for Ron. Amanda was aware of Ron’s uncertainty, and might have been willing to undergo the surgery for his benefit.

「Now then, we’ll be going to collect the drop of the World Tree, so doing the surgery tomorrow should be fine.」

「Yeah, please and thank you.」

I shook hands with Amanda and turned towards Ron.

「Can we meet at the gate that leads towards the World Tree in an hour, Mr. Shuji? I have to meet the lord.」

「The lord? Why’s that?」

I wondered if the Adventurer’s Guild Master also needed permission from the lord to enter the World Tree. Then Ron said something unexpected.

「I’m going to borrow Sunrise. With it, we can reach the seventh level in just a few hours.」

It looked like Sunrise was purchased by the lord of Yggdrasil. He planned to display it in the town’s museum later. This showed the lord and Ron’s amicable relationship and their trust in each other. Rather than helping for free, it may have been his gesture of support for Ron and Amanda when he bought the staff at a high price.

「Miria, I’ll leave everything to you while I’m gone.」

「Okay, be careful.」

Reina, Neumann, and I were already prepared to enter the World Tree. The current time was 9 am. If we entered the World Tree with Ron after meeting up, we should reach the seventh floor by this afternoon, and then we could return immediately with Reina’s Teleport. Neumann’s face was slightly apprehensive when he heard we would use Teleport, but he didn’t object to it. A few days ago, he told the story about having experienced Teleport at the bar, and the adventurers there wanted him to tell them about it. The ones who heard him decided they wanted to experience it for themselves one day. That was why Neumann didn’t seem to reject the idea of using Teleport this time, but he probably wouldn’t be of much use afterwards.

The town of Yggdrasil was built south of the World Tree in order to prevent the tree’s shadow from covering the town. If they were under its shade, the sun would only shine on the town for a few hours, so the only place to establish the town was to the south of the World Tree. One caveat was that its root system spread extensively towards the south.

The seventh floor of the World Tree referred to a place near the main trunk of the tree, where there was a hollow that continuously produced sap. Up to that point, it was just a long journey of approaching the World Tree while avoiding its roots.

「Sorry to have kept you waiting.」

Ron didn’t seem much different from usual, other than the fact that he was holding Sunrise. Having gone to the World Tree many times, the seventh level must have seemed like a walk in the park for him. We went down the path that was pioneered to some extent by adventurers. Neumann was in the lead with Ron following behind.

「We need to reach the seventh floor as quickly as possible and collect the sap. Neumann, walk faster.」

「Even if we walk fast, won’t it still take a few hours?」

Neumann, whose back was being poked with Sunrise, was a swordsman, but Ron’s steps were no less firm. I heard that Ron had retired from being an adventurer a long time ago, but it seemed he never slacked on his training.

「Neumann, this way.」

Ron stopped Neumann, who was heading towards the World Tree through the normal route. Reina and I have only come here once before, so we left everything to Ron because I didn’t remember much.

「No, but Guild Master…」 「It’s fine, climb here.」

The path Ron showed was a considerably thick root of the World Tree, about two stories tall. It was stabbed into the ground, and while I didn’t know how far it stretched, we could climb the part that entered the ground like a slope.

「There are griffons on the root though.」

Located on top of the roots of the World Tree were the nests of griffons. This was confirmed by occasional sightings of them flying from Yggdrasil, and they were formidable beasts ranked between A and S. It was also said that they attacked in groups.

「It’s fine, just go already. Hurry up!」

Ron, losing his gentlemanly demeanor, pushed Neumann up the root. We followed them up the roots as well.

「What a beautiful sight.」

The scenery where I could see both the sky and the World Tree was beauty I’d never seen before, as I had mostly walked under the roots. However, I could already see the griffons.

「Hey! We were noticed right away after all!」

Ron shook off Neumann’s protests by waving Sunrise.


A fireball formed at the tip of the staff and expanded. Ron gave out instructions while holding up his staff.

「Neumann, we’re going to run along the roots all the way to the trunk.」

The griffons seemed to hesitate before attacking us as Ron could fire his magic at them at any time. Occasionally, Ron would throw a fireball at a distant griffon and several griffons would flee, fearing the heat. There were still other griffons observing us, but none of them attacked.


「Just run!」

Neumann ran along the roots while being prodded from behind as we and Ron followed behind. With this, I estimated we would reach the seventh floor of the World Tree within an hour instead of several hours.

「Griffons don’t like fire! When I was active, I often ran to the World Tree like this!」

「Why didn’t you tell anyone?!」

「Well, no one can actually one-shot a griffon with an Explosion!」

Indeed, it wasn’t like he intentionally kept this strategy a secret, it was just that no one else could utilize it. When I looked at Reina beside me, she was showing a face like she could do the same. After hearing this, it seemed like a good method to get the drops of the World Tree next time.

「Hey Reina. Can you use Explosion?」

「Who do you think you’re talking to? But that scale of destruction is impossible without a staff at the moment.」

Ron could probably only cast it thanks to Sunrise. That was why he had gone to the lord and borrowed it. Should I buy a good staff for Reina? I thought it was a necessary expense… but would it be impossible after all?

Doctor Editor’s Corner: A couple of things here. Sterilization is extremely important in preparation for surgery because of all the crazy bacteria out there. You can’t always trust just boiling things in water or soaking them in disinfectant and assume things are perfectly clean. There are bacteria and viruses that are resistant to chemicals and there are even ones that are resistant to boiling water. That is why the auto-clave method was developed, which actually utilizes both pressure and temperature to kill practically everything other than tardigrades and those life forms that live by undersea vents (but what the hell would one of those be doing on a surgical instrument?). Standards are also strict and everything sterilized has a little indicator in the bag it is stored in that shows that the appropriate pressure, temperature, and time in the autoclave have been met. If the indicator did not change color, you gotta resterilize it again.

TL/DR: Sterilization is very important, and we do a good job of doing it.

Another thing big here is the importance of consent. At least in the US, everything requires the consent of the patient (and their guardians or power of attorney). I really do mean everything, from medications, to lab orders, to surgical procedures, and even to the person examining you. If you don’t want something done, it is 100% your right to refuse. That doesn’t mean that you get to pick and choose what the alternative is, and certain things may piss off your clinician, but at least you can refuse something that you don’t want. You can also refuse it at any time before it is done. Obviously you can’t refuse a medication if it’s already been administered, but right up until that medication is injected, swallowed, stuck up your butt, whatever, you can refuse it. Same thing here with the surgery. No matter what consent form you had signed prior to the surgery, you can cancel it until it has been completed. They can have you in the OR, and you are right about to go off to dreamland, and you still have that right to cancel the surgery. Of course, if you’re being unreasonable, constantly canceling multiple things last minute, your doctor/surgeon will probably stop wanting to see or treat you, but if you’re really having second thoughts and want things to stop, they have to stop. Just remember that most of us doctors and surgeons recommend what we recommend because we want to keep you and/or get you healthy. Believe me, it’s a lot easier for us to just say, “you’ll be fine, just go home and sleep it off,” because then we don’t have to do anything like follow up visits, or read and interpret test results. I’d prefer reading WNs instead. Oh and in the case where you leave an ER or hospital against medical advice (AMA), in certain parts of the country, insurance might not pay for the hospital visit depending on the circumstances. Refusal of treatment is your right, but there are consequences to certain things. For example, if you don’t get vaccinated, you can’t go to schools in certain states/cities. If you don’t get that infected appendix taken out of you, you die in some adventurers guild’s medical clinic. There are a few exceptions to this whole consent thing. One is presumed consent, where basically in an emergency situation, you’re already out cold, you’re dying, and no one else is around to give consent, then we’ll assume you want us to do everything we can to keep you alive, including shoving weird things down your throat, shocking you, and taking out organs. Even then, there are things called advanced directives, that will tell us things like no intubation (no shoving the aforementioned things down your throat), no surgeries, no blood transfusions, or even just let you die. And we’ll have to follow what that paper says. Another exception is when you’re a little kid and you don’t want to get a shot (vaccine) or get that nasty cut stitched up, and your parents say, “Yeah, hold that little %$#@ down and sew him up. That’ll teach him not to play with my officially licensed Frostmourne replica!” In that case, we don’t need the kid’s consent, it just helps a bit. BTW, yes I have had kids strapped down, wrapped up head to toe like a burrito, and screaming in my face while I sutured a cut on their forehead that would have otherwise left a nasty scar. Good times.

TL/DR: You can refuse any kind of medical care unless you’re not awake or are a snot-nosed brat, and please don’t be a dick about it or your doctor will break up with you and/or you might die.

One last thing: regarding COVID-19, I’m sure you’re sick of hearing about it, and so am I, so I’ll leave it with: Stay safe and healthy everyone!

– Index –

Isekai Surgeon
Chapter 7