“Box breathing” and similar breathing exercises that call for breath holding, even for a few seconds, can aggravate respiratory conditions such as asthma and COPD. In some cases, even deep breathing can trigger respiratory symptoms.
(ID: an animated gif showing a diagram of box breathing, where you breathe in for 4 seconds, then hold for 4, then breathe out for 4 and hold for 4, in a continuous cycle. End ID.)
I didn’t learn this until a couple years ago, and a lot of people still don’t know! Talk with your medical providers about alternatives!
I personally use in through the nose, out through the mouth exercises (like “smell the roses, blow out the candles”). Inhaling through the nose is best for asthma, since the nose filters some particles and irritants, and warms and moistens the air going to your lungs, all of which can help reduce symptoms. I specifically don’t hold my breath in between those steps!
Alternatives to breathing exercises include techniques such as distraction, identifying 5 sensations, fidget tools, listening to music, putting on a favorite show, or guided meditation.
Distraction is great when hyperventilating, most people, when mentally distracted, will fall back into a normal breathing pattern naturally. Sometimes focusing on your breath and body *isnt* the answer or even necessary.
so there is this concept that we think everyone should at least hear about and it;s called the respirocirculatory ginch it's very important. the ginch has the lung heart (which can inflate/deflate as necessary) full of pumping air and not pumped blood. it grew three sizes yeah but it did also it did shrink. he also has lungs. our dear respirocirculatory ginch with the inflatabl! heart. he's geen
Turns out I never posted it here, but three years ago I rendered @jayrockin's character Talita's upper respiratory system just for kicks, and since the inner workings of her head are still knocking around in mine, she gets to be a Blender file now! The muscles and bones I've added to this new render aren't *necessarily* canon for this species' design, but speculation is fun : )
Watching Demon Slayer as a healthcare professional: appreciating the little details
Welcome to my medical nerd-out post. If you’re interested in the intersection of real-world medical practice and what’s shown in these scenes, read on! Disclaimer that my current background is in anesthesia, and I previously worked in emergency medicine.
(I’m going to cosplay Shinobu at cons later this year and this will be the sign I’ll print and tape to the back of my costume. I feel like this is a very Shinobu thing to say.)
People joke about this bit a lot, and yeah it looks silly, because Zenitsu looks anything but okay here, but would you believe me if I told you that this is actually part of Basic Life Support (BLS) protocol? In an out-of-hospital emergency, usually what happens first is someone collapses for whatever reason. The first thing BLS trained personnel must do is assess the victim's consciousness, like ask if they're alright, just like what Shinobu did here, before proceeding to other interventions if needed, like CPR, rescue breaths, applying and using an AED, etc. I wouldn't want to jump right into giving CPR if the victim is arousable and can breathe. Another first thing to do to check someone's status is feel for a pulse: carotid artery in adults, brachial or femoral artery in small kids. Things go from 0-100 real fast when there's no pulse or breathing. Reassuring to know that apparently Shinobu is trained in BLS.
Flicking the syringe is a legit thing to do. As an anesthetist I draw up IV medications for surgery all day every day, so I flick my syringes all the time. It's to bring air bubbles to the surface of the liquid, so it's pushed out with the plunger before the medication is given. Air bubbles in veins is no bueno, especially in pediatric patients. Some of those kiddos have congenital holes in their heart, called a patent foramen ovale or PFO, and bubbles going through that hole would plug up the circulation, which would be disastrous. (I’m a preceptor in addition to my basic clinical duties, so I make sure students prime their IV lines and medication infusions properly to flush out any bubbles, especially for kiddos.) Push enough air into the vasculature and you get air embolism, an intraoperative crisis. I appreciate Shinobu doing her due diligence not wanting to give Zenitsu air embolism.
A little detail the anime did not show is using aseptic technique to wipe the injection site before injecting. Skin is a natural barrier to outside bacteria and other pathogens. Anytime you stick a needle into someone to establish an invasive line like IVs, arterial lines, central lines, and even just an intramuscular injection like a vaccine, that skin barrier breaks, potentially introducing pathogens further inside the body. The injection site must be wiped down with some sort of antiseptic prep before inserting the needle and injecting that medication. I understand that most likely for animation convenience, Shinobu is shown giving an antidote to Zenitsu by intramuscular or subdermal injection. In the real world, it would be more proper and beneficial to establish an IV and deliver the antidote that way. Pharmacologically speaking, medication given intravenously achieves its desired effects much more quickly than other routes like oral or intramuscular. You want medicine to work systemically (basically spread all over the body where it needs to go), and the quickest way to do that is via bloodstream. It's like carrying mail or cargo to its destination on the freeway at 70 mph versus a residential road at 20 mph, it's just so much faster by freeway. Almost all medications given in the OR are through IV, that’s why establishing IV access before surgery is so important. Real life standard antivenoms are given exclusively by IV, though at a venom conference I attended very recently, there's a novel antivenom in oral form/powder, so that's exciting development. (This is not a criticism of the anime, just what I think is a good talking point to delve into.)
Conducting airway exams is done across several medical specialties, especially in anesthesia. Anesthesia providers do more than knock out patients with gas and meds. We also place airway devices like endotracheal tubes, which delivers oxygen, air, and anesthetic gas via ventilator during the maintenance phase of surgery. Assessing a patient's airway before surgery tells us how easy or difficult it would be to place those airway devices. We look for things like mouth opening, anatomical landmarks like the uvula, hard palate, soft palate, and tonsils, neck circumference, any loose, chipped or broken teeth. There’s something called a Mallampati score that anesthetists use to assess the inside of someone’s mouth, that’s why we ask the patient to open wide and stick out their tongue. The less anatomical landmarks seen, the lower the score, so Mallampati 1 is the best and Mallampati 4 is the worst. Signs that point to likelihood of what we call a difficult airway: thick neck, no chin, limited neck range of motion, a Mallampati 3-4 score. When I have a student with me on a given workday, I make them do their own airway exam on our patient and tell me their findings, to see if they align with my own. Of course you can’t really do a proper airway assessment in a non-elective, emergent surgery, like when a trauma patient comes rolling in. (I work at a trauma center, so that situation is not uncommon at all.) When a patient has an unstable cervical spine or a messed up jaw (I’ve seen some pretty screwed up faces from knife and gunshot wounds), that’s where airway management gets real interesting. We have many creative ways to get that endotracheal tube in.
I couldn't help geeking out a little when Shinobu said she put anesthetic in the water she gave to Tanjiro. I headcanon that she laced it with benzocaine, a local anesthetic. In real life, we use benzocaine, more commonly known as hurricane spray, for transesophageal echocardiograms (TEEs). A TEE is basically a long skinny scope that goes down the esophagus and lets the cardiologist look at heart rhythm and function. This is how irregular heart rhythms and valvular diseases are diagnosed. Patients are instructed to swish around the benzocaine and gargle it in their throat to numb it up before the cardiologist sticks their TEE down there. The patient gets further sedation from anesthesia for this procedure.
Local anesthetics definitely have their use, like in spinals and epidurals, but giving too much is actually toxic, and getting to that point is called local anesthetic systemic toxicity (LAST). It’s a big deal; ORs have a supply cart specifically for treating LAST. It’s really important for surgeons and anesthetists to know the maximum dose for a given patient and procedure, so we don’t end up giving the patient too much. Each local anesthetic has its own unique max dose in mg/kg, and the more the patient weighs, the more local anesthetic they can get. I like to think that Shinobu guesstimated Tanjiro’s weight and put an appropriate amount of benzocaine in the water.
Anesthesia is a medical specialty that entails extensive knowledge in respiratory mechanics, anatomy, physiology, and pathology, because it’s how we keep patients alive during surgery, so we are known by other medical specialties as the “airway experts.” Naturally I’m very intrigued by the use of breathing techniques as the magic/power system in Demon Slayer.
Total Concentration Breathing actually isn’t totally off-base. In the real world, unfortunately, we can’t use it to pull off superhuman feats and kill demons. But in the setting of controlled elective surgery, that’s basically what we make patients do. It’s called preoxygenation. If you’ve ever had surgery under general anesthesia before, you’re familiar with this experience: being rolled into the OR, having vital monitors hooked up, then a mask placed over your face and you’re asked by the anesthetist to take big, deep breaths. After that you “don’t remember anything” (at which point you’re given anesthetic medications to go to sleep). On room air you’re breathing mostly nitrogen. Right before surgery and going to sleep, we deliver high flow 100% oxygen to the lungs via the anesthesia machine. This optimizes the patient for the next step after induction of anesthesia/“knocking you out”: intubation. The measurement to gauge how oxygenated you are is oxygen saturation (or SpO2 for short). This refers to how saturated the body’s red blood cells are in oxygen. That’s the continuous beep on the monitor you hear in all those medical shows, the light blue wavy line that should normally read 90-100%. The pitch of the beep correlates with the amount of saturation: the higher the saturation, the higher the pitch. If you work in the OR, one of the most ominous sounds is a low SpO2 pitch. (The sound of my nightmares!) The reason why we want a patient to have the best SpO2 they can achieve before going to sleep is because the most common medications we give during anesthetic induction, propofol and rocuronium, stops breathing and paralyzes muscles respectively (muscle paralysis sounds scary, but don’t worry, there’s a reversal drug given at the end of surgery!) The clinical term for this cessation of breathing is apnea, like in sleep apnea. Healthy patients have an apnea window of a few minutes. During that apnea window, the patient is intubated and connected to the anesthesia ventilator for the duration of surgery. Some patients don’t have great functional reserve in their lungs, like kiddos (due to their physiology) and sick people (due to some pathology), so their apnea window is much slimmer, so less time to intubate before their oxygen saturation starts to drop. SpO2 dipping under 90% makes OR staff nervous.
As mentioned in the anime, it’s true that greater blood flow and lung capacity benefits your respiratory function. Some patients, however, have suboptimal parameters and that complicates anesthetic management. Common causes include major blood loss, obstructive or restrictive lung diseases, being significantly overweight. In addition to that, many childhood syndromes negatively impact the lungs, one of the many reasons why pediatric anesthesia is more challenging than adult anesthesia. In some thoracic cases where surgery needs to be done on a lung, like to remove a lung tumor or something, that lung needs to be deflated through one-lung ventilation and placement of a special double-lumen endotracheal tube. These can be very tricky cases to handle from an anesthetic standpoint, because the patient is getting ventilated through only one lung, but I like doing them. I could very easily get lost in the weeds of respiratory physiology, but I’ll cut it short here.
Because Hashiras are in peak shape and are so proficient in their breathing techniques, I expect their oxygen saturation to be no less than 100% if they came in as patients for surgery! I’m sure that of all the Hashiras, because of her medical background, Shinobu has the greatest technical understanding of breathing techniques.
I love to explore how real-world science and medicine is featured and applied in pop culture, so I hope you found this post educational and entertaining. Next post I want to do is categorize Hashiras into medical specialties, that'll be fun.
Had a test today so I drew up the Respiratory system to help me study. Even labelled a bit. (Got an A so I was probably doing something right 😌.) It’s super sketchy but it was a late night thing so idc rn.
