Lazette Gifford
Publisher & Editor


Written in Blood

By Lisa Blair
Lisa Blair

We've all seen it -- that scene in a movie where someone gets a slash to the jugular on one side of the neck, only to start spurting blood and fall over stone dead in under a minute.  Some of you probably laugh at scenes like that.  Others might cringe or go wide-eyed with horror.  But if you're like me, you might wonder, could that really happen?

The answer is no.

As a nurse and writer, I often get called upon to answer medical research questions and bust these kinds of misconceptions.  What follows is information to make a good starting point for writing about blood, in all its gory glory.  Please keep in mind that humans are miraculously diverse and there are exceptions to everything.  If you're trying to write a character with a specific blood-related or blood-borne illness, or a medical thriller, I suggest you do further research.

Using the Five Senses 

The goal of writing is to immerse the reader into the character's situation as thoroughly as possible.  There's nothing particularly tricky in writing about blood using the fives senses, except that many people have very limited experience with the quantities of blood they want to write about.  Instead, they must rely on sometimes inaccurate information from other sources.  What follows is an attempt to provide an accurate foundation for writers working outside their own first-hand experience. 

Only a moderate to large quantity of blood produces a noticeable smell.  Fresh blood smells metallic or coppery, while decaying blood smells sickly-sweet with an underlying hint of copper.  Don't forget that sometimes it's not just the blood tickling the nose -- blood from childbirth smells sweet, ranging from mild to foul, due to the amniotic fluid or "water" around the baby.  Gut wounds have a nose-wrinkling foul smell, and the reek of infection can overpower the smell of blood quite easily.

Most people have probably tasted blood.  That coppery flavor is hard to miss, but be aware that a normal, living human swallowing more than a few tablespoons will soon feel very ill and may vomit.  Fresh blood feels slick, but once it dries, it will harden to form a crust.  Dry, blood-soaked fabric is very stiff.

Listening to blood falling into a puddle is probably a less common experience.  Blood is a liquid, but it isn't water; it is thicker, heavier, and more viscous.  Try an experiment using some thinned ketchup to see what it sounds like for yourself.

Sight is by far the trickiest of the senses to use when describing blood.  Why?  Because blood doesn't all look the same.  Fresh from an artery, it will be scarlet in color, while blood from veins will be darker red.  Further, blood coughed up or leaked from a lung looks pink and foamy.  Blood released from an hours- or days-old blister, boil, or blood-filled, bruise-like lump will be thick, almost black, and very viscous. 

How Blood Works

I've pulled out some of the most common questions and misconceptions I have heard and tried to give a basic idea of the facts.  All numbers and statements are based on averages for a healthy adult (so please excuse me if your experience differs -- we're all unique, after all).

The human body contains about 4-6 liters of blood, depending on size and gender, though a woman in late pregnancy will have nearly double that.  How much a person can lose without dying depends on how much help there is available.  In a pre-transfusion society, probably no more than a liter would be "safe" to lose, less if the person is starved or unhealthy.  In a modern setting with adequate health care, more like 2 liters could be lost, much more if the person is being constantly transfused.  A pregnant woman will lose half her volume during and following the birth without any negative consequences.  Heavy bleeding may cause a serious condition known as shock -- clammy skin, pallor, bluish lips and fingernails, rapid heartbeat, low blood pressure, confusion, unconsciousness, and rapid breathing are some of the signs to watch for.  Without help, a person in shock has minimal chance of recovery.

Arteries carry blood away from the heart.  Because the heart acts like a pump and forces blood through these vessels, pressure inside the vessels varies.  That's why when an artery is cut the blood will "spurt" out in waves, not spray steadily.  How fast and how high the spurt goes depends on the heart rate, the size of the blood vessel, and the size of the cut.  A small artery like that in the wrist will bleed slowly and a person may take hours to "bleed out" into shock or death, whereas a large artery can lose blood at an alarming rate and result in death in minutes. 

Cutting an artery probably sounds like a good way to kill someone off fast and painless, right?  Wrong.  Arteries are composed of thick connective tissue and smooth muscle.  They are tough, and they are usually buried deeply within other tissue, making them hard to get to. Further, they are surrounded by nerve endings -- the body wants you to know if your artery is damaged! One possible exception: the carotid arteries are located on either side of the neck and are the major arteries that feed the brain. While they are still tough and difficult to get to, a very deep cut could do sufficient damage, resulting in fainting as the body tries to get flat to increase circulation to the head.  The heart would continue to beat until either it had insufficient blood or the brain died, though.  If both carotids and the jugulars that return blood to the heart are cut together, brain death can occur in as little as 17 seconds.  Though it takes a little longer if only one is cut, survival with one cut carotid is highly unlikely, even with a surgical team on stand-by.

Veins return blood to the heart after it has filtered through the body.  Veins have thinner walls than arteries, with no muscle, and are under very little pressure.  These anatomical differences accounts for how the blood "spills" out of veins instead of spurting.  Again, the larger the vein, the faster the blood will spill out.  Large veins are located in all the limbs, the torso, the groin, and the neck, but are also buried deeply within the tissue. Bleeding to death from a cut in a large vein is possible, but it would take much more time than from a cut in a large artery -- several minutes at least -- and a victim has a much better chance of survival with treatment.  The veins closer to the surface of the body are small, and while the amount of blood from a moderately deep cut can seem alarming, there is no real danger of a healthy person bleeding to death from one. 

That pesky jugular we hear so much about really is a special case. Of the large veins, it is the closest to the surface, the easiest to injure.  That said, people do survive jugular cuts in a modern setting.  There will be an enormous amount of blood from a wound like this, and to survive, the person needs emergency care from a professional and probably several transfusions.

Bruises form when blood vessels break but the skin doesn't.  Rather than spurting or spilling out, the blood pools under the skin.  Bruises usually start out looking reddened, then turn to a bluish-black.  As the bruise ages, it will fade from the skin gradually, and can go through any number of color changes, usually from blue-black to yellow-green.  The healing time for bruises depends on the amount of blood involved and the person.  A young, healthy person will find that small bruises fade over a day or two and larger bruises take up to a week.  An elderly or ill person may take two weeks or longer. 

Bruises can be really painful, particularly if centered over a joint or a nerve center. A person bruised from head to toe is not going to be capable of running long distances, riding a horse, or doing any other manner of miraculous feats of athleticism.  In this case, pain is the body's way of saying, "Knock that off!"  If that message isn't heeded, the body will literally shut down the affected parts and make them useless.

Circulation Basics

I've talked about what blood does outside the body and just under the skin, but what about problems with circulation? Cutting off the circulation to a body part for a few minutes will result in the part "going to sleep" -- tingling, with sharp little jabs of pain as the circulation returns.  If you've never felt this, try sitting on your ankle for a few minutes and then walking across the room.

If the circulation is cut off to a limb for much longer than that, the body tissue starts to suffer from lack of oxygen.  The limb appears pale and cold to the touch. The cells need oxygen, and without it they start to build up acidic wastes.  After as little as four hours without oxygen, the effected limb will literally die, turning black and withering.  If left attached, this dead limb will likely result in a serious or fatal infection; thus amputation is often the only remedy once things have gone this far.

Circulation can be only partly cut off, as is the case with a medical condition known as Compartment Syndrome.  This occurs when a limb is trapped in a tight space that collapses the thin veins but leaves the thicker arteries still open -- like a tight ring on a finger, or a leg in a cast too tight for the swelling.  As blood is forced into the limb by the arteries but is unable to return to the heart, the limb will swell.  After a short time, the swelling increases the  pressure until the arteries close off too, resulting in limb damage and death if the pressure is not released.

Some Final Advice

Keep in mind, that while you are now armed with the knowledge of many of the technical details, your reader only needs to get a sense of what you mean.  Being overly technical -- specifying how many ounces of blood have been lost, for instance -- can pull the reader out of an otherwise engaging moment.  It's important for you, the writer, to know that Johnny has lost half his blood volume and will be going into shock soon, but it's not important for the reader to know that that number is 2 liters.