What Happens To Your Body When You're In A Coma

"The patient is in a coma" is one of the most terrifying things a doctor can say. The thought of an involuntary unconsciousness that you may or may not wake up from is arguably up there with the worst-case medical scenarios, like a cancer diagnosis. And the mysterious nature of a coma just adds to the horror. 

Then again, isn't it basically just being asleep? How bad can a coma really be?

The short answer is: Pretty bad. The longer answer is the same, only followed by a rant about a coma being a horrific condition in so many ways that you've probably never imagined. That being said, a coma is far from a simple state of being. Depending on the patient and the situation, it can be any number of things, and your average person probably doesn't have a clue what they might be up against if they're ever unfortunate enough to go under. We can't prepare you for such a terrifying scenario. However, we can help you understand how a comatose state would treat your corporeal form. Let's take a look at what happens to your body when you're in a coma.

How can you end up in a coma?

Since we're discussing the comatose state, it's probably best to take a look at the very beginning of the road to a coma and (hopefully) back. However, we immediately run into a problem, because the root cause of a coma is not as clearly defined as you'd think. As the Mayo Clinic and the National Health Service of the U.K. tell us, the causes for a coma are many and various. Much like "sleep" can mean anything from a blissful eight hours of rest to a terrifying, nightmare-filled catnap, "coma" is a catch-all term that can be caused by any number of things, if they become serious enough. A bad enough head injury? A coma's a possibility. A brain tumor, or maybe stroke? Sure, classic coma causes. Overdid it with alcohol or narcotics? Absolutely! In fact, if things go really awry, even comparatively mundane conditions, such as infections or diabetes, can send a person into a coma. That seems pretty harsh, really.

With all these ifs and maybes involved, a coma is a pretty serious thing that requires a doctor to swiftly find out the underlying cause, in order to deal with the situation in the first place.

When the coma begins

A coma is essentially an umbrella term for a long state of unconsciousness, which can be caused by a massive array of different health problems, according to the Mayo Clinic. It's definitely an emergency situation, and the person should receive medical attention as soon as possible. Calling an ambulance is likely a no-brainer if there's an accident or stroke involved. According to Medical News Today, there are also certain types of coma, such as ones caused by high blood CO2 levels or low blood sugar, that start with the person getting agitated and increasingly confused before finally passing out. 

However, even if a person falls into a coma because of some less identifiable reason, there are ways to tell that they're not just having a really good nap. A coma patient's eyes are generally closed, and their breathing may be irregular. They tend to have no pain response at all, apart from certain reflex movements — but not brainstem reflexes, which more or less take a holiday. This is why a comatose person's pupils don't contract and dilate properly, when subjected to light. Oh, and there's also the main symptom that comas are known for: The person simply can't wake up.

Please don't attempt to diagnose this stuff yourself if you suspect someone's in a coma, though. The 10 minutes you spend browsing WebMD would be much better spent by calling for help, so doctors can use their brain CT scans and blood tests to figure out exactly what's up.

Testing for different types of coma

There are many underlying causes for a coma, but as Medical News Today informs us, the actual condition also comes in many varieties. As such, it's pretty important to figure out the type and deepness of the patient's comatose condition to ensure best possible care. Luckily, there are ways to do precisely that. 

The first responders can use the AVPU scale (Alertness, Vocal stimuli, Painful stimuli, Unconscious) to determine just how out of it the person is, and precisely what sort of an emergency they're dealing with. When the comatose person is taken to a hospital, a more thorough assessment known as the Glasgow Coma Scale can be applied. The GCS is a handy, practical method that tests the patient's ability to open their eyes, as well as the level of their verbal and motor response. With these tools and an array of tests at their disposal, the medical professionals can gain insight on what caused the coma, how deep it is, and how it should be treated. 

It can stop you from breathing

It's easy to think of a coma as a really deep sleep and little else, but the comatose state can actually wreck a person's body in a number of interesting and, let's face it, creepy ways. For instance, Medical News Today informs us that it's perfectly possible to enter a coma that's so deep that you can't even breathe properly. If that's the case, the doctors might have to ensure that the airways remain open and breathing continues, and the patient might have to spend their coma time with a tube up their breathing bits, in order to prevent them from asphyxiating.

Incidentally, asphyxiation can also quite easily cause a coma, as a 2010 study by the researchers at Landspitali University Hospital in Reykjavik, Iceland (via Wiley Online Library) reminds us. So, it's technically possible to get stuck in a vicious circle where the person first asphyxiates so badly that they end up in a coma, and is then at a constant risk of asphyxiation because of said coma.

Your muscles atrophy like no one's business

As the NHS tells us, a comatose person is usually taken care of in an intensive care unit, and because of the nature of the condition, the patient's body is likely to experience some pretty unpleasant changes. While the best-case scenario for a coma patient is waking up with all their faculties intact, there's a chance they've gained a new, debilitating illness in the process, according to a 2016 study by the researchers at St. Michael's Hospital in Toronto, Canada (via Science Daily). 

Because a coma prevents you from using your muscles like you normally would, spending time in a coma would be likely to cause your muscles to atrophy. What's more, some ICU patients' muscles are permanently damaged, which leads to physical weakness and even disability. Disturbingly, whether this affects a patient or not appears to be a crapshoot. "We know ICU patients lose muscle mass and function," says respirologist Dr. Jane Batt. "Critical illness literally causes their muscles to dissolve. Some people grow it back and some don't." So, add "melting muscle mass" to the rapidly expanding pile of horrors that come with a coma.

Coma patients can move, laugh, and cry

Imagine visiting a comatose family member in a hospital, only for the serene, sorrowful scene to be interrupted by the patient's limbs suddenly flailing around for no reason at all. Horrifying, yes? 

Don't worry, your poor relative isn't possessed or anything. Most people think that coma is a pretty quiet, unmoving state, and it can certainly be just that. However, sometimes it ... isn't. Comas come in many flavors, and as the University of Iowa Hospitals & Clinics website tells us, the fact that a comatose person might not "respond consistently or appropriately" doesn't necessarily mean that they remain perfectly still. Brain injury patients can have several types of reflexive movements, which range from straightening and bending of the arms and legs to the limbs moving randomly, for no particular reason. 

Somehow, moving their arms and legs isn't even close to the strangest thing a comatose person can do. According to the National Institutes of Neurological Disorders and Stroke, some coma patients might take things to the next level by sometimes spontaneously grimacing, crying, or even laughing. 

The intricacies of an intentionally induced coma

A coma is a pretty serious condition, but as Scientific American tells us, it can also be a pretty important tool when doctors are out of other options. A medically induced coma is precisely what it says on the tin — a form of anesthesia that can put you under when your injuries are bad enough to necessitate such an extreme maneuver. Of course, the induced coma is also reversible. Otherwise, what would be the point?

According to Business Insider, a medically induced coma can be used to counteract the brain swelling caused by severe head trauma, in order to prevent brain damage or even death. The method relies on the coma slowing the blood flow and metabolic rate, which in turn reduces the swelling. Essentially, the doctors put your brain on a little time out in an attempt to give it some time to recover. Arguably, the most famous person who has been treated in this manner is Michael Schumacher, the famous Formula One driver who received terrifying head injuries in a 2013 skiing accident. 

You may be able to hear and understand people

The idea of losing your consciousness and being reduced to a barely functioning body in what may or may not be a permanent sleep state is horrifying. The idea that all of that happens, but you're still somewhat aware of what's happening around you is arguably even worse. Unfortunately, Medical News Today tells us there have been cases where comatose people can "hear and understand spoken instructions," even though they're still very much under.  According to the Guardian, in 2011, a group of researchers in Ontario, Canada scanned the brain of a man who had been in coma for 12 years, while asking him to imagine doing different things, like playing tennis. The man's brain activity showed that he was doing just that.

The implications of being conscious, yet unable to wake up are pretty creepy. While all comas are different and there's no telling how aware of their surroundings an individual patient is, the NHS recommends that visitors assume the patient can hear and understand them. As such, you should remember to tell the comatose person who you are at arrival, speak to them normally, and generally be supportive. Maybe whip out some headphones and play them their favorite music, as well.

Comatose and conscious?

Here's where things get really weird. According to the Guardian, the advent of fMRI (functional magnetic resonance imagining) has taught us all sorts of new things about comatose people. One of those things is that while many coma patients are quite incapable of emotions, feelings, and thoughts, an estimated 15 to 20 percent of them are totally conscious but trapped inside their helpless bodies and uncooperative brains.

Nightmarish as this may seem, the NHS reminds us that for the majority of coma patients, the situation is far from eternal. Most people start regaining their consciousness after a few weeks in a coma, and being aware of their surroundings can actually be helpful. According to research, providing stimulation to the comatose person's senses may aid the recovery process, and those who have woken up from a coma have reported that they sensed when their loved ones were present, and that it gave them strength.  

Come comes with a deadline

Once you're in a coma, you're working against a deadline. As National Geographic informs us, that deadline is roughly one year after you fell under. After that, you're generally considered a goner — sure, your body is still around, but there's a reason it's called the "vegetative state." The consciousness that made it you is unlikely to return ever again. Seeing as Mayo Clinic notes that most comas only last for a few weeks, this means that everyone's probably going to get pretty nervous after the first couple of months. 

Of course, comas vary from person to person, and the fact that there's an arbitrary point of no return doesn't mean that people never come back from comas that last over a year. In fact, in 2017, French researchers were able to "boost the consciousness" of a man who had been comatose for 15 years. This is pretty significant, because brains generally don't come back after a decade and half of vacation time. The researchers achieved this with a special implant that stimulated the vagus nerve, a huge nerve that plays a part in a person's attention and "wakefulness." It took a month of regular stimulation, and granted, the guy didn't magically regain his faculties like they were never gone. However, the procedure helped him reacquire an ability to understand simple commands and react to various situations. Who knows what medical science will be able to do for long-term coma patients in the future?

Coma can be an endless nightmare

One might expect that the ability to dream would make a coma less dull. As Business Insider tells us, this is indeed true, but not necessarily in the way you expect, particularly if it's a medically induced coma — which is, after all, essentially a form of anesthesia. Turns out, it can lead to some pretty interesting imaginary experiences, and by "interesting," we mean "incredibly scary." 

People who have been in an induced coma have described the experience as a constant nightmare you can't wake up from, and that it actually took longer to heal the psychic scars from the hellish nightmares than it did from physical ailments. Of course, there's also the other end of the spectrum. In 2012, neurosurgeon Eben Alexander wrote in Newsweek that he visited heaven during his seven-day coma. 

According to Dr. Michael J. Souter of the University of Washington in Seattle, such hallucinations and nightmares are probably just the comatose person's brain scrambling to understand the sounds that keep trickling in from the outside world. While that does sound more scientific than vivid visions of heaven and hell, we can't help but feel that doesn't really matter when you're stuck in an incredibly detailed hallucination that you absolutely cannot wake up from. 

Your heartbeat may betray how likely you are to wake up from a coma

For a condition as complicated as a coma, it's difficult to say exactly when the person wakes up — or, for that matter, what their odds are for doing so in the first place. However, according to a 2014 study published by the European Society of Cardiology (via Science Daily), there are certain tricks you can employ to predict the survival odds for at least one type of coma patient. This particular method applies to comatose OHCA (out-of-hospital cardiac arrest) patients and involves the measuring of a heart rate during therapeutic hypothermia. In other news, yes, therapeutic hypothermia is a thing. They use it to protect the patient from brain damage. 

After a cardiac arrest, it's pretty difficult to give the comatose patient's loved ones an accurate prognosis in the first three or four days, which is obviously massively stressful for everyone involved. As the researchers were trying to find a way to predict survival rates more accurately, they discovered that a very particular heartbeat during hypothermia may correlate with lower brain damage, and therefore better chances for survival. So, sinus bradycardia, which Healthline defines as a special type of slow, steady heart rate that's under 60 beats per minute, might indeed be good news for this particular type of coma patient.