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Subscribe to RSSWrites Bill Briggs: Ever grabbed some floor after glimpsing some blood?
Does a mere peek at the red stuff – yours or anybody’s – make you feel woozy and wobbly?
If so, you can thank your Uncle Caveman or Aunt Cavewoman.
This reaction is primeval stuff, buried deep within our brains. It goes by the name "vasovagal syncope." More importantly, medical experts believe fainting at the sight of blood probably helped some of our ancestors survive some horrible things. (So stop teasing folks who take a quick trip to Dreamland whenever they spot the tiniest trickle of the vital fluid: We may owe them our very existence.)
While only a portion of humans experience the phenomenon, “it’s a reflex that’s built into every person on this planet,” says Dr. Fred Jaeger, medical director of the Center for Syncope and Autonomic Disorders at the Cleveland Clinic in Ohio. He’s studied these bewildering blackouts for 26 years.
“Times of severe stress or injury or fear can trigger the reflex: your blood pressure drops, your heart rate slows,” Jaeger says. Most medical experts speculate that such fainting spells are likely rooted in evolution – an ancient instinct that somehow kept a foothold in our DNA as we spent eons maturing.
“For example, if you’re a caveman and another caveman man comes over and cuts your arm off, the sight of blood or injury may cause you to faint,” Jaeger says. “So when you’re laying there on the ground, you’ll look like you’re dead to the other caveman and he won’t cut your head off.
“This goes back to the time when we were hunter-gatherers, warriors, Cro-Magnon people,” he adds “Vasovagal syncope probably had some benefit – if you were injured and you lived to fight another day, the gene would be carried on. Just like survival of the fittest.”
Another bonus for those early humans who keeled over at first blood: their blood pressures dips and heart rate drops also slowed their bleeding, which helped the stay alive.
While doctors believe the reaction is unique to humans and primates, some animals – like possums and a certain breed of goats – are known to swoon and become momentarily unresponsive when peril is present.
About six in 10 people will faint at least once due to this strange syncope. Common triggers include pain, standing for long periods or standing suddenly after a big meal. When the sight of blood causes the collapse, doctors dub that “phobic fainting.” For people who suffer chronic, fear-based fainting spells, (like going to the dentist) doctors will prescribe medications that work with their brains or nervous systems to keep them upright.
But why do an unfortunate few go horizontal each time they catch a flash of blood?
Researchers are analyzing genes and hormone levels. They’re hunting for clues in enzyme deficiencies.
“What is it in the makeup of easy fainters? We’ve got to suspect they just have this gene that is very easily triggered,” Jaeger says. “But that is the million-dollar question.”
Do you faint at the sight of blood? Tell us about it.
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The people are going horizontal at the first sight of blood, not vertical.
Oh man, thank you so much for catching that, Krista! Just fixed.
Some friends and I were boating on the James River and we saw a guy run face first into a tree on a jet ski. We pulled him out of the water and into our boat and he was bleeding pretty badly and another friend of ours went right down, so we had two men down. It was pretty scary all around as we didnt know why the guy fainted but when he came to he told us he always does at the sight of blood.
I first fainted at the age of two watching my brother get a shot at the doctor's office. Especially when I was younger, I could not see blood or hear anything remotely gory and I would hit the floor. I used to average about one complete loss of consciousness per year. My triggers are shots and descriptive stories about blood and guts. I haven't completely passed out in 3 or 4 years because I have finally just began to walk away if a particular conversation or college lecture begins bothering me. I get a drink and lay down and the dizziness passes very quickly. While I have never been able to prevent the sick feelings, at least I have learned how to stop myself from completely losing consciousness.
How ignorant can these supposed medical researchers be? This is an acute Psychological reaction that induces a psychsomatic reaction. Note onset through fear, stress, panic etc. requires a psychological reaction before there is a change in the nervous system. There are biological, involuntary responses like being knocked out by a blow to the chin that rotates the neck and spine so quickly that the nervous system takes over inducing shock or blackout, but seeing something, especially someone else's blood is hardly physical cause and effect. The brain interprets the seriousness of blood loss based on past trauma and causes the heightened stress and drop of blood pressure to ramp up the bodies defense to fear or revisiting of past trauma. Being able to discipline your thoughts to counter the part of your brain that responds and assesses fear, will decrease the drop of blood pressure, maintaining blood flow and help you cope with the incident. Adrenal Stress training keeps soldiers from fainting, boxers from being knocked down etc. 26 years and he is trying to find a monkey gene? What a duck or a quack! Perhaps he should study the next 26 years on what monkey gene is responsible for someone to spend 26 years making a monkey of himself.
I'm not sure if you've ever met anyone with the "phobia", but it's not necessarily caused by past trauma. My fainting started around the time I hit puberty. Though I have never had or seen an accident involving copious amounts of blood, I still faint at the sight of more than a droplet. Even cartoon blood bothers me. Over the years, I thought I could "cure" myself by giving blood--facing my fear directly. Ten years and two coffee mugs later (1 Gallon and 5 Gallon donor), I still get woozy picking a splinter out of my husband's finger.
Funny. When I was in college, I was pre-Med for a long time, focusing heavily on Chemistry (which is what I ended up with). I loved Anatomy! Dissection didn't even set off my wooziness (no blood). I took a Phlebotomy class so I could use it to start working in the field sooner rather than later... and fainted by the third session, dropping the class the next day. Blood sucks. lol
The first time I went with my dad when he gave blood, I was about seven years old. I remember watching the bag slowly fill up with blood and then apparently face-planted. I woke up to a kindly nurse rubbing my hands. She fed me orange juice and cookies, which I thought was pretty cool. Never had it happen again.
Oh ya! That's me! The first time I fainted I was about 10 or 11 and I was watching my Aunt have a small biopsy in her doctors office. I thought it was the coolest thing ever. The next thing I knew I was laying on the ground with the nurse and doctor over me asking if I was okay. Now I know, when I see blood fainting is a possibility. I say possibility because somehow, occasionally I don't faint. I chalk this up to adrenaline. When I am the only other person and someone is hurt I don't faint. Maybe I know I have to help this person and the adrenaline keeps me from dropping. That's my best guess anyway, and I'm thankful for it. Whatever it's cause.
I cut my leg in the shower and my then-15-year old daughter came in to use the sink. I stepped out and said , "Wow it looks like a scene from PSYCHO in there, haha," flinging back the curtain to show her. Next thing I know, her face went pale, lips turned blue and BOOM, she hit the floor. You can't even SAY the "B" word around her, lol!
I fainted ONE time, and that was at that same age I was watching my mother get blood taken at the hospital. That seems to be the only thing that bothers me, when blood is drawn into the needle and then bag. If I just don't look at it and I'm fine.
Waterbearer, I'm the same way--about the blood going into the IV set and into the bag. I get too analytical about it and imagine the escaping blood is creating a vaccuum at the injection site and blood is being corralled/sucked from other parts of my body as a response. Its this mental image that creates the light-headedness and feeling like I'm about to go out. Not watching doesn't help, and it only happens when this is my blood. I'm a medical professional and I often have need to access the veins of others, and seeing their blood has no effect on me. Wonder what gene I've inherited from the cavemen that gives me that strength?
oh man, yeah, happens sometimes, sometimes i can avoid it. but i fear the day i have kids and God forbid they get hurt, i hope i dont faint!
I've never fainted but I used to get woozy. Then I had a weird flashback experience to the summer I was 5. First I split the skin on top of my head open, then cut a slit in my mouth. Both wounds bled profusely. I also had several stitches both times with no anesthesia. Once I realized it had probably somewhat traumatized my little 5 yo mind, and was probably the reason for my wooziness; I've never gotten woozy at the sight of blood again.
I fainted once while reading an online article about primitive lobotomy techniques. Blood doesn't bother me, but thoughts of scrambled brains, or of the potential loss of the things that make me who I am, inevitably cause me to feel dizzy, anxious and lightheaded.
Funny thing is, I only faint at the sight of my own blood...not at somebody else's. I've done it three times in the past couple of years. It used to freak me out until my doctor told me it's probably just a drop in blood pressure...as the article also stated.
I can watch YOU bleed all day. It is when I bleed that it makes me woozy.
Does anyone else find the explanation that losing consciousness would be advantageous because then your attacker would assume you're dead and not deliver a truly killing blow totally ridiculous? That seems like quite a stretch to me. It would be more advantageous to remain vertical and aware so you can deal with whatever is causing the blood. Fight or flight.... but if you faint at a small amount of blood (not even your own), you'll likely suffer (potentially additional) wounds from crashing to the ground and hitting things on the way down. Net effect? Bad evolutionary tactic. I don't buy it.
I was thinking the same thing! The fainting tactic might work if lets say your fighting in a large group and your just trying to take people out. Then maybe the person standing doesn't have time to check the person on the ground, he's just ready to move on to the next guy. I once saw something on tv about a dog that kept fainting whenever it got excited, only the explaination then was synoptic overload and the dog's brain had to shut down.
I think that the reduction in blood pressure to reduce blood loss is a much more likely reason.
I've only had it happen once, at a hospital clinic where I'd taken a friend to get stitches for a wound on his hand. Seeing the wound didn't bother me, but when the doc started poking around with a needle for the local anaesthetic, I started feeling woozy. The last thing I remember is thinking "I gotta find a place to sit down", and the next thing was waking up to see several concerned nurses watching me. I got to my feet, and they checked my blood pressure and it was waaay low! I normally have a low blood pressure (about 110/75) but it had dropped far below that. The nurse said it was the lowest blood pressure she'd seen and still be conscious.
So, yeah, it's probably a reduction in blood pressure to reduce potential blood loss from injury and improve blood clotting.
Almost every time I have to give blood I am ok for about 20 seconds, then i break into a bad cold sweat, get really faint, and sometimes i pass out or sometimes it starts to go away after 5 minutes. but for those 5 minutes it is just the most awefull feeling. and i see this micro little LEF-bright light go across my vision, straight from left to right, go up and down like a little mountain, continue straight, then exploed like a fire work, and it repeats. If i do pass out, when i wake up my hands are clinched so tight that it has actually taken me a few minutes to relax the muscles and open my hand. That is how tense they get. If you can give blood and not feel dizzy and nautious, then I envy you.
and no, the actually needle going in me doesnt bother me and seeing a little bit of blood doesnt bother me. but seeing blood moving in tubes, bags or tubes of blood, and especially the feeling of my blood moving through the tube really does it to me.
I faint at the site of blood and disfigured people. I will even faint visiting a friend in the hopsital after having a baby... just seeing the IV in their arm will do it for me. I have two children who both have had a serious illness. When they first were admitted to the hospital I would not faint, but during the recovery occassionally I would be in their rooms and the nurse would come do something with them and I would faint. I think initially I was able to deal because of the adrenalin rush from being a parent but after that I would be back to myself fainting at everything. I wish I could get over it. I missed the birth of my grandchild because I went pale in the room and they made me leave. I even pass out listening to someone's gross story.
I find that if I leave when I first start feeling sick,drink something cold and lay down a few minutes, I recover quickly.
I agree. Also, having lifelong problems with vasovagal syncope due to other triggers, I know that as soon as you hit the floor, the blood is restored to your brain and you're conscious again. you wouldn't look 'dead' for very long, certainly not long enough for an attacker to say 'he's dead. i can walk away now.'
I love watching my blood get taken. It is so cool to watch. I've never really been afraid of the sight of blood.
I am almost 30 years old and I still sometimes pass out at the site of blood...my most recent accident was 2 months ago when I cut my finger dicing a tomato. While the "Vasovagal syncope" term applies, my passing out mostly comes from my open-heart surgery at 4.5 years of age. My doctors informed my parents that I would either have nightmares or pass out. I can tell before I pass out (except when I was little) and that's when I lay down...I'm only out for a few seconds too. This happens to me if it's my blood or someone else, even if it's just a trickle. Sometimes I can fight it but most of the time, "I'm out for the count" (as my mom would say growing up). I also get light-headed and pass out after blood is taken from me. I bet some are wondering about "that time of month", I do not pass out (sorry to guys who read this).
I'm one of the "unfortunates" who has to use prescription medication to control my vasovagal syncope. It isn't just the sight of blood that sets me off--it can sometimes be something as simple as listening to someone talk about an injury or surgery. However, I've had a few surgeries myself, and have even been hospitalized for an illness, and I did not faint then. There's really no rhyme or reason as to what will set me off, but it's a really difficult thing to live with. Many people don't understand, and they even make you feel bad about it. I get called "a delicate flower" and "Victorian" all the time. The funniest part? I love horror movies--the grosser, the better!
I pass out when I have blood drawn, but it has nothing to do with the sight of blood. My blood pressure is normally very, very low (90/64) is my normal low. When they use any type of needle other than the butterfly needle, then I pass out. The regular size needle draws the blood too quickly and with the low pressure, then BANG! Out of the count.
"butterfly needle" has nothing to do with the size of the needle - only the shape of the plastic part that is held in the hand of the person sticking the needle in.
Oh bull! Blame it on the parents and ancestors. Its just a mental thing that causes people to do that. They envision it happening to themselves. Simple. No genetics about it. And besides, it wasn't survival since you had to spill blood to get a meal. They would have fainted themselves dead(literally) away to the animals which snack on them. If you pass out, you're exposing yourself to danger. Mostly women faint which shows the femininity of the weaker sex.
It shows your ignorance that you don't understand how genetics is essentially the same thing as "blaming it on your parents and ancestors," as you say.
Weaker sex, ha! Haven't heard that one since my great grandfather was around thirty years ago. Looks like we have a bona fide caveman right here!
You are wrong about it being mostly women.......I am a pre-op nurse and the vast majority of fainters during needle sticks are men.
I don't faint at the sight, but the experience of having even a small amount of blood drawn (whether or not I look at it) has triggered a shock-like reaction several times. Cold, clammy, stars in the eyes, nauseous, and - um - other unpleasant symptoms that cause me to spend the next 30 minutes in the bathroom. My brain seems to be interpreting it as trauma, even though consciously I'm not freaked out about it.
I guess I'm lucky. Giving blood doesn't bother me and seeing blood doesn't bother me. But when I am either giving blood or having blood taken for testing, I REALLY don't like to watch the insertion of the needle. From the time I was an infant until I was 6 I received shots once a week, so I really don't like needles.
Interestingly enough, my mother could help at Red Cross blood donations without a problem except when my dad was donating. As soon as she saw his blood going into the bag, she fainted.
I've had this problem since I was a little kid. The first time it happened, I was 7 and badly cut my hands on some dried corn stalks. I'm now 25 and have passed out almost 2 dozen times during my life. Forget going to the doctor and having blood taken - the nurses have to drug me every time. There's only one other person in my family who has this problem and she was an RN for years! I know that I have gotten better over the years though. In high school, I couldn't even listen to my biology teacher talk about the circulation system. Now, I can watch Grey's Anatomy, E.R. and most other medical shows without every even feeling queasy. There are certain triggers though. I can't stand my own blood being taken in a doctor's office; I can't stand beads of blood like when a diabetic has to poke their finger for a small sample of blood; I can't stand even the idea of slit wrists; I can't stand on shows if I see someone bleeding to death or dying from blood loss, i.e. vampires on a show completely draining someone.
For me, it's not the sight of blood, but the sight of a needle. Or any conversation about veins. If I know that something (needle) is going to puncture my vein or the vein of anyone else, I can't take it! I haven't had blood drawn for a medical check-up in 4 1/2 years because the technicians can't do it! The last time someone tried, I was actually being a good-little-soldier and coping. Until. The nurse said something like "Well, I got it in, but it's so weird. Your blood stopped flowing." That was it - I was on the floor!
What a senseless theory. You are far better staying conscious and treating the source of the bleeding as quickly as possible. If the injury were serious enough the subject could bleed to death before regaining consciousness. Remember people - don't panic, don't freak out, think clearly and treat the wound properly. The last thing any patient (including you) needs is for you to confirm trouble - compose yourself, reassure the victim (you included again) and provide first aid. Stop the bleeding.
Interesting sampling from the responders here. Seems to be quite a few who fainted seeing a blood donation. I did the first time, but never since. Though I didn't become a nurse, I always thought I might be good at it because I'm not squeamish. But that very first time... yeah, dirt nap.