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This giant metal cylinder is a Magnetic Resonance Imaging (MRI) scanner. Inside this 8 foot long donut is a bunch of super strong magnets. These magnets are so strong they cause the hydrogen atoms to get excited and shoot off a little radio wave. These radio waves are picked up by antennas in the donut and used to make a really lovely picture of your innards. More water = more hydrogen = brighter spots on the picture.For those Quorans who haven’t had the pleasure of an MRI I can tell you from personal experience that it is rather anxiety inducing. Imagine being stuffed in a long dark tube with your head in a box, wearing cheap earphones. You can look at a prism in the top of the box and see your toes and little else. You can’t move your head. They tell you to lie still. When they fire the thing up it sounds like a giant with a hammer pounding on your iron prison. They issue earplugs to people in the room to prevent hearing damage from the volume. Not surprisingly people are frequently sedated. For some people oral sedation just is not enough.Anesthesia is called in because, to get these lovely pics, the patient must remain motionless for several minutes. Some people just can’t hold still and must be sedated, up to and including general anesthesia. This takes an MRI from a non-invasive, risk-free procedure to one requiring IV access, supplemental oxygen, and a tired old anesthesia provider (MD or CRNA) and some risk.These are the people who frequently need anesthesia.Infants and young kidsAdults with phobias and psychiatric issuesMentally challenged patientsCritically ill people who require ventilatory and hemodynamic supportPatients who are unable to lie flat for any amount of time. (heart failure, morbid obesity, severe COPD, etc.)MRI anesthesia is a subset of what is referred to in the business as NORA (Non OR Anesthesia.) Anesthesiologists have a comfort zone. For the most part we practice in well-lit, well-supplied ORs with lots of helpful nurses, O2 on tap, suction available, and all of our drugs at hand. We often have a very comfy chair and toasty blankets.MRI rooms were designed by Satan. The goal was clearly to be as difficult to do an anesthetic in as possible. They are often hidden in the hospital basement, miles away from supplies and helpful staff. MRI rooms are refrigerated to keep the magnets happy. The machine takes up so much room that the rooms are lit like a medieval dungeon.Look at the first picture. You will notice that the nice skinny patient fits comfortably on the two-foot wide table. Over her face they have what I like to call “the Box of Obedience.” Next, notice how long that donut is. When she is in there, her face (airway) is literally 6 feet from the edge and almost completely in the dark. Is she breathing? Who knows. (In ancient times we used to tape glow sticks to their chests just to see them move up and down with breathing.)Magnets are the crowning achievement of Satan’s plan to make anesthesia as difficult as possible. These magnets are so strong that they will suck metal objects right out of your pockets from several feet away and send them rocketing into the patient’s eye.An illustrative anecdote: In a former job one of our CRNAs brought a steel E-cylinder of O2 weighing 14 lbs. (6.76kg) within 5 feet of an MRI. The cylinder was sucked into the MRI tube and bounced around before sticking to one of the walls. The MRI was broken. The hospital sued my group for lost revenue and repair costs. I felt lucky because a patient stuck in there would have been beaten to death.The first thing you must do to enter the MRI chamber is divest yourself of all magnetic stuff. Badges, watches, phones, wallets, etc are removed. This is supervised by the MRI tech. Oh, and that other stuff you wanted to hook to the patient? Nope, it’s all got ferrous metal in it. No tools, no monitors, no cart, no ventilator, no oxygen tanks, no nothing.There is an entire industry that makes nonferrous equipment for MRI suites. Blood pressure, pulse oximetry, end-tidal CO2, EKG and even complete anesthesia machines are all non magnetic and (in my experience) not nearly as reliable as the other stuff despite being hideously expensive.Our current practice for MRI anesthesia requiring general anesthetic involves anesthetizing the patient in another room and wheeling them into the MRI suite. We take our monitors off before they enter and put them on the table and reattach the MRI monitors.Great care is taken not to put any wires too close together because the intense magnetism will induce a current in them. If they're too close, wires can amplify induced current and cause heating. Nothing better than waking up with a new brand burned into your chest.We connect the endotracheal tube to a ventilator outside the room with a good 20 feet of tubing. Patients are kept asleep with propofol delivered by several yards of tubing. This is really fun when the patient is an infant or young child. By the term “really fun,” I mean really scary. We sit in the booth with the MRI tech. When the magnets are on we often lose oximetry. Thankfully they are over in 30 - 45 minutes.https://basicsofpediatricanesthesia.com/section-iv-pediatric-surgery/418-2/30-mri-control-room-anesthesia-1/Fortunately we have never had a code blue while I was there. When it has happened, they pulled the poor person out of the scan and onto a gurney and out into the prep area while doing chest compressions because the defibrillator was non-MRI compatible.TLDR: A person can indeed be anesthetized for an MRI. It’s expensive and a complete pain in the ass but it happens every day.

What we knowCOVID 19 is a disease entering through the respiratory tract, can sometimes result in respiratory distress, respiratory failure (need for ventilator) and even more rarely a multi-system multiple-organ affliction resulting in fatality. But fortunately most cases are mild and asymptomatic and pass off like a flu. Despite some cases being reported to develop long term respiratory complications like chronic breathlessness, most surviving this illness do well.-The SurpriseNow suddenly, our knowledge turned upside down with this study result.100 patients surviving COVID with no clinical or biochemical (test) evidence of cardiac disease underwent cardiac MRI scanning - a test that looks into not just the anatomy but tissue characters of the heart. In this study, the test was done on an average of 90 days (3 months) after recovery from COVIDThe ScareThe results - 78 of those 100 had significant abnormalities in the heart, mainly the muscle tissue of heart by MRI scanning.(Late Gadolenium Enhanced Cardiac MRI showing cardiac damage)Ref : JAMA August 2020; available online.Some with severe MRI changes had a myocardial biopsy done to see the degree of damage. They showed significant myocyte (heart muscle cell) damage with lymphocyte infiltration.(Grey - Heart muscle cells; normally tightly packed, here shows separated by empty spaces because of inflamation. The dots are cellular infiltration)Ref : JAMA August 2020; available online.Interestingly, 67% of these patients didn’t even need hospital admission since they had very mild COVID.This scares me as a cardiologist.Mild COVID with no symptoms had ‘subclinical’ ‘undetected’ cardiac damage in 78% cases, shown by MRI scanning done 3 months after recovery. Will they gradually become normal or the amber of inflammation slowly burn and ravage the heart over time?Only time will tell.I keep all my fingers crossed.

Years ago, I had a droplet of molten metal fall into my ear. I was underneath a trailer, welding a bracket when this happened.Yes, it was painful and I came out from under, screaming and dancing a jig.I went to the ear doctor. He took a look and told me the drop is lodged into the tissue right beside my ear drum. He said removing it would be dangerous. He advised to just let it be and maybe it would be expelled naturally.Fast forward some ten years and I was going to get an MRI. I told the technician about the metal droplet that may be in my ear. He did not like this at all, but I really needed the MRI.BTW, MRI machines use a very powerful electromagnet to produce a map of what is inside your body. How powerful?He presented me with this plan: He was going to put me on the bed, well away from the magnet and program the bed to slowly move towards the magnet. If I feel anything in my ear, I can stop the procedure by pushing a button he provides me with.All goes well and afterwards he told me that there is no trace of the metal blob anymore.As you might have guessed from the video above, had there been a metal blob in my ear, it might have been ripped right out of my head as I screamed in agony or at least ruptured my eardrum.I am very happy to have skipped that part.So if you ingest ferrous metal like iron or steel, and go inside an MRI machine, you would most likely die.If you were to get very close to an electromagnet scrapyard crane, you would likely die.