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Category Archives: Medical Issues

Q and A: What Happens When a Person Is Exposed to the Vacuum of Space?

Astronaut

Q: What sort of damage does the human body suffer in the vacuum of space?  How long can one survive and what will happen to the person who does survive?  My scenario involves an astronaut whose faceplate blows out, but not before he depressurizes his suit sufficiently to prevent immediate death.

A: First of all the victim would not explode as was the case in the movies such as Total Recall. But some very bad things do happen internally and they happen very quickly. Whether he depressurizes somewhat beforehand or not, his survival once he reached zero pressure (vacuum) would likely be measured in seconds.

Space decompression sickness is similar to that of a scuba diver that rises too rapidly after a prolonged exposure to the pressures of the deep. In this case the diver is going from excess pressure to normal pressure. In space the victim goes from normal pressure to zero pressure. Same thing physiologically.

In diving, the problem is that the excess pressure causes excess nitrogen (N) to dissolve in the blood. This N will come back out of the blood as the pressure is reduced. This should happen slowly to prevent decompression sickness or the bends. But, if the diver rises rapidly, the pressure drops rapidly, and the N comes out of the blood quickly, forming N bubbles in the blood stream. This is similar to popping the top on a soft drink. Here the release of the pressure allows the carbon dioxide (CO2), which was placed into the liquid under pressure, to come out of the liquid and form bubbles. We call this carbonization. A good thing for your soft drink, but not so good for your brain and heart and muscles.

In space decompression basically the same thing happens. Apparently the culprit is water and not N in this situation, however. With the sudden release of pressure, the water in the blood “boils,” becoming a gas, and bubbles form in the system. I should point out that in chemical and physical terms boiling simply means the changing of a liquid to a gas. This can be accomplished by adding heat (boiling water on a stove) or by lowering the ambient pressure (popping open a soft drink). In the case of space decompression it isn’t that the blood gets hot, but rather that the pressure that keeps the water in its liquid state is removed and the water changes to its gaseous state, or boils. Doesn’t sound very pleasant does it?

Though studies on the effects of exposure to a vacuum have been done on chimpanzees, there are no real data on what happens to humans exposed to zero pressure except for a couple of incidents where an astronaut or a pilot was accidentally exposed. Of course, rapid decompression has caused deaths in both high-altitude flights and in June, 1971 when the Russian spacecraft Soyuz 11 suddenly lost pressure, killing the 3 cosmonauts on board, but survivors are few and far between.

On August 16, 1960, parachutist Joe Kittinger ascended to an altitude of 102,800 feet (19.5 miles) in an open gondola in order to set a world record for high-altitude parachute jumping. He lost pressurization in his right glove but proceeded with his ascent and jump. He experienced pain and loss of function in his hand at high altitude but all returned to normal once he descended via chute to lower altitudes.

In 1965 at NASA’s Manned Spacecraft Center near Houston, TX, a trainee suffered a sudden leak in his spacesuit while in a vacuum chamber. He lost consciousness in 14 seconds, but revived after a few seconds as the chamber was immediately re-pressurized. He suffered no ill effects—due to his very brief exposure—but stated that he could feel water boiling on his tongue. This was actually the above mentioned boiling scenario in which water (in this case saliva) becomes a gas on exposure to zero pressure.

A case of partial, prolonged exposure occurred during an EVA (space walk) in April 1991 on the US space shuttle mission STS-37. One astronaut suffered a 1/8 inch puncture in one glove between the thumb and forefinger. He was unaware of it until later when he noticed a painful red mark on his skin in the exposed area. It appeared that the area bled some but that his blood had clotted and sealed the injury.

So, what happens to a human exposed to zero pressure? Since there is no oxygen in such an environment, loss of consciousness occurs in a matter of seconds. Also, if the victim held his breath (don’t do this during scuba diving when coming up from depths either), the air in his lungs would rapidly expand and his lungs could be damaged, bleed, or rupture. Better to open his mouth and exhale the rapidly expanding gas from his lungs.

Water in his blood stream would immediately begin to “boil,” filling the blood stream with water vapor (the gas form of water) and stopping his heart. Bubbles might appear in the blood stream and cause damage to the body’s organs, particularly the brain. As a result, the brain and nerves cease to function. As more and more gas formed within the body, the entire body would swell but it would not explode.

Exposure to heat or cold or radiation might also occur but it will do little harm since the victim would already be dead.

But what if the exposure were brief and the person rescued? Treatment would be to immediately return him to a pressurized environment and give him 100% oxygen. He may survive unharmed or may have brain and nerve damage which could be permanent.

For your scenario, whether he partially decompressed or not, he would be in trouble very quickly. When your victim’s faceplate ruptured he would hopefully begin to exhale air to prevent the expanding gases in his lungs from rupturing them. As air, and thus oxygen, flowed from his lungs and into space, the oxygen content of his blood would rapidly drop and he would lose consciousness in 10 to 20 seconds. He would then die in short order. If he were quickly rescued, he would be returned to the spacecraft, which would be pressurized, and would be given 100% oxygen via a face mask. He could survive intact or with brain damage. It’s your call. Either way works.

 

Would Lincoln Have Survived With Modern Medical Treatment?

Lincoln 1863

Lincoln’s assassination took place 150 years ago this evening. He died the next day, April 15, 1865. Since he lived overnight, could modern medicine techniques have saved him? Here is a question that appeared in my second Q&A book—FORENSICS AND FICTION

Would Abraham Lincoln Have Survived His Injuries Today?

Q: This is a pure curiosity question. Do you think that Lincoln could have been saved if they had today’s medical knowledge, techniques and equipment in 1864?

Martha Kuhn, Mt. Gilead, Ohio

A: Most likely, yes. He was shot in the back of his head, and the bullet apparently entered his brain. He lived for many hours so the shot was not immediately fatal. A surgeon probed the wound but feared removing the bullet, since it might cause bleeding. He probably should have, but we’ll never know.

Similar wounds today are treated by a trip to the OR, removal of the bullet, controlling bleeding, and preventing any subsequent infection. He would have had at least a 50 percent chance of survival. And since he survived several hours anyway his survival with modern techniques would likely have been much higher.

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Posted by on April 14, 2015 in Medical History, Medical Issues, Trauma

 

Heartbeats and Art

First a little semantics: Arrhythmia actually means “without rhythm.” So the only true arrhythmia is asystole or cardiac standstill, which means the heart has no rhythm and simply sits there quietly. Not a good thing. Not compatible with life.

The proper term is dysrhythmia, which means an “abnormal rhythm.” There are many different types of these.

Some are slow:

Sinus Brady

Others are fast:

SVT

We all have dysrhythmias but most of us are totally unaware they are happening. Other folks experience palpitations—-an awareness of a cardiac irregularity. These can sometimes be alarming and I regularly see patients in my office with this complaint.

Beethoven

But can your heart’s rhythm effect your creativity? Did a dysrhythmia contribute to Beethoven’s musical prowess? Did Shakespeare’s heart beat in iambic pentameter?

As a cardiologist, I’m not sure I buy into this but it is intriguing:

http://www.medicalnewstoday.com/articles/287809.php

 

Do Astronauts Hallucinate?

It has long been known that isolation can lead to all sorts of psychological problems, including delusions and hallucinations. Prisoners in isolation, who have limited interaction with others, can suffer just such effects.

In medicine, we see it frequently. Someone has surgery, and then for whatever reason (complex surgical problems, complications, co-morbidities, etc.) must linger in the ICU for a few days. This is a form of isolation as they are limited in their activity and in who they see and talk with on a regular basis. Sort of like prison isolation. Not to mention they might be receiving medications for pain, sleep, or agitation, each of which can alter mental function. After as little as a couple of days, the person can become confused and disoriented and suffer delusions, such as everyone is trying to kill them, or they are being held prisoner and undergoing some alien experimentation, as well as hallucinations where they see, feel, and hear things that don’t exist. Seen it hundreds of times. It’s that common.

icu

It even has a name: ICU Psychosis.

Astronauts are in a similar situation. They spend months in an enclosed, monotonous environment, interacting with the same people, day after day. It’s like prison, or an ICU. Do they also develop delusions and hallucinations? It seems that the do. In fact, I would be surprised if they didn’t.

astronaut-moon

So, during a trip to Mars, where isolation is very real, could such psychiatric problems jeopardize the mission? You bet. NASA takes this seriously and has begun studies into such long-term deprivations.

HI-SEAS

MedNet: ICU Psychosis: http://www.medicinenet.com/icu_psychosis/article.htm

NIH: Intensive Care Unit Psychosis: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2154033/

Astronauts and Hallucinations: http://www.theguardian.com/science/2014/oct/05/hallucinations-isolation-astronauts-mental-health-space-missions

NASA Trains Astronauts to Bins, Tranquilize Unstable Crewmates: http://www.foxnews.com/story/2007/02/25/nasa-trains-astronauts-to-bind-tranquilize-unstable-crewmates/

NASA Has Guidelines for Dealing With Psychosis in Space: http://www.utsandiego.com/uniontrib/20070224/news_lz1n24read.html

Mars One Astronaut Training Program: http://www.mars-one.com/faq/selection-and-preparation-of-the-astronauts/how-are-the-astronauts-prepared

NASA’s HI-SEAS Training Program: http://www.sci-news.com/space/science-nasas-hi-seas-team-hawaii-mars-mission-02220.html

 

Medicine Is Strange: Stone Man Syndrome

f1

Medicine has a lot of very strange disorders in its catalog of maladies.

Fibrodysplasia Ossificans Progressiva (FOP or Stone Man Syndrome) is one of them.

http://thechirurgeonsapprentice.com/2014/12/17/disturbing-disorders-fop-stone-man-syndrome/

 

Hacking Pacemakers For Murder No Longer the Perfect Crime

Pacemakers can be hacked but that’s not news. We’ve known that for a while.

St_Jude_Medical_pacemaker_in_hand

Newer models are even easier to hack than were the older models. Progress being what it is. Most pacemakers are interrogated and adjusted in the doctor’s office or the Pacemaker Clinic by placing a “wand” over the pacemaker and then using an attached computer to retrieve data stored inside and/or change the parameters of the pacemaker—-changing sensing, pacing thresholds and rates, that sort of thing. Many newer models allow for more remote access—-from several feet away. Think “blue tooth” for a pacemaker.

Heart-039-s-Natural-Pacemaker-2

F1.large

This more “remote” access allows for hacking to take place without direct contact with the patient. The pacemaker can be changed, even turned off, which in someone who is “pacemaker dependent” for their heartbeats can be catastrophic, even deadly. Fortunately most pacemaker recipients are NOT pacer dependent so even if the device is turned off they would still do fine. Maybe a bit weak, tired, and dizzy, but not dead from heart stoppage.

Now it seems that, though this can still be done, traces are left behind. Makes getting away with such tampering more difficult.

Guess you crime writers will have to find another way to off your characters who have pacemakers.

 
 

Want To See Something Very Small? DNA Replication Visualized

This is cool. You probably remember from high school biology that DNA copies itself as the first step in cell division. This is how we grow and how we replace lost or damages cells.

 

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The replication process begins when the two strands of our double-stranded DNA “unzip.” That is, they split form one another. Then each stand rebuilds its complementary strand in a complex biological process. This yields two identical strands of double-stranded DNA, each of which becomes the nuclear material for the two identical cells when the division process is completed.

Current DNA analysis mirrors this natural phenomenon. State of the art DNA profiling employs the combination of the Polymerase Chain Reaction and Short Tandem Repeat analysis (PCR-STR). It’s the PCR portion that utilizes this natural process of replication, which is also called “amplification.”

Now it seems someone has used electron microscopy to visualize this process.

Amazing.

DNA Replication RCN.com: http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/D/DNAReplication.html

You Tube: DNA Replication Video: https://www.youtube.com/watch?v=27TxKoFU2Nw

How Stuff Works: DNA Replication: http://science.howstuffworks.com/life/cellular-microscopic/dna3.htm

DNA Forensics: From RFLP to PCR-STR and Beyond: http://www.forensicmag.com/articles/2004/09/dna-forensics-rflp-pcr-str-and-beyond

 

 
 
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