Showing posts with label defibrillation. Show all posts
Showing posts with label defibrillation. Show all posts

Friday, June 19, 2009

TERMINATOR SALVATION - Spoiler Alert #4

MARCUS' HEART
The dialogue of the film reminds us on occasion of Marcus' heart. Blair (Moon Bloodgood, Rowr!) mentions it beating strongly when she seductively snuggles up to him and lays her head on Marcus' chest. Connor tells Marcus he sees his "heart beating a mile a minute." However we never see it directly, only through Terminator-vision at the end of a fight, so we don't know it's a human heart. Marcus' metallic skeleton at his chest is exposed but his heart is never visible to us.
Marcus' naughty parts

Here's a picture of Marcus' skeleton that I got off of Rotten Tomatoes. You can see that Marcus either has an organic heart encased in that metal skeleton, or perhaps he doesn't have a heart at all. Maybe the machines gave him some kind of mechanical pump that only sounds like a heart in case he has to snuggle with a human female.

Everyone mentions his heart. We all get it. Marcus has a strong heart. It's robust, can pump blood through an organism made of a combination of organic and manufactured materials, and is the symbol of his emotions, values, and humanity. Marcus' heart is the key to the final action, his redemption, and John Connor's life (so that there can be another movie -- spoiler alert #4.5!). The way the film works this material is both irritating and entertaining.

MARCUS TO THE RESCUE
In the factory during the final big action scene, Connor defribillates Marcus with industrial cables not because he is a being of value, but because Connor can use him as a weapon against a Terminator. Connor needs a weapon, and Marcus is it. But before the revived Marcus can stop it, the Terminator shoves a pipe through Connor's chest, where his heart would be if he had one(1). That is a great moment! It's shot really well, the welling blood suits their palette, and the action is well timed. Marcus then saves Connor and helps get him back to the base.


YOU KNOW THORAX
Back at base, Connor is dying because "his heart is too weak." Really? That's it? How about a collapsed lung, massive loss of blood, perhaps a sucking chest wound, fractured ribs splintering into everything, and insane amounts of bleeding around the mediastinum?

Below are some pictures of the chest. The mediastinum is essentially the area between the lungs, housing the heart in the "pericardial cavity". The lungs, heart, and other tubes are partitioned off from one another by sheets of connective tissue, sometimes referred to as membranes.

Here we see the heart and its vessels nestled in the mediastinum, between the lungs.

This is similar to an aerial view. The sternum is at the top of the picture, the vertebral column at the bottom, center. We see the lungs (right and left) and many of their blood vessels. We also see the top of the heart and the vessels from the lungs leading into the heart (in blue... yes, blue); these are essentially located within the borders of the mediastinum.

If bleeding happens within a partitioned area, the membranous walls keep blood from going everywhere. If one lung collapses due to blood in the chest (hemothorax[2]), the other lung can function because the blood won't leak into its space unless these partitions are compromised.

After Marcus rescues him, Connor seems to be able to breathe and is not hacking up blood loogies, so the pipe and splintered ribs have obviously not pierced his lungs or their cavity (the plural cavity for you trivia buffs). His breathing would be pretty labored if he had a hemothorax or pneumothorax(3) situation. So what the heck happened? What is the scenario to fit the shot of the pipe emerging from Connor's chest, with all that blood welling up?

The only thing we can assume is there is bleeding (and swelling) around Connor's heart, causing compression to its chambers. This is called cardiac tamponade(4). The pressure from the blood build-up would reduce the amount of blood that could get into the heart, reducing cardiac output. To compensate, the heart would have to beat faster to try and get enough blood around the body. This condition would indeed weaken and exhaust the heart. This is the only condition I could possibly come up with to support the action and the script. I'd be curious to know what the writers were thinking...

Here's an illustration of cardiac tamponade from a World War II surgical manual. It's comforting to know that traumatic injuries suffered in the 20th century will still be around well into the 21st century...

I LEFT MY HEART IN SAN FRANCISCO...OR WAS IT L.A?
So, Marcus tells them to take his heart and transplant it into Connor's body. It is Marcus' chance to redeem his criminal life and sacrifice himself for a higher cause. What does Marcus get from Connor for his heart? A curt nod. No "thank you" or, "I guess you're human after all" or anything. Obviously Connor will never need a penis transplant. He's a big enough one as it is.

Then they perform transplant surgery out of doors under a netted camouflage tent. Grit and dust aren't sterile. There is a lot of bacteria in dirt, you know. As an example, anthrax bacteria can live in dirt for years and years. Wind can blow all sorts of bacteria into a wound. They should also do some blood and tissue typing before wasting Marcus' heart, if he even has one. If Connor doesn't die of infection, he may die of tissue rejection(5), which means... no sequel!

Anthrax Bacteria (the rod-shaped things)

CYBORGS AT LARGE
Thinking about Marcus (only professionally, of course) as the first human-based cyborg to show up in a Terminator film, I started thinking about cyborg films, generally. Expect the next entries to be an exploration of the meat/metal interface.

1. Connor's character is so self-centered! Let's face it, if I grew up with a mother who taught me to use firearms and told me I was destined to be the savior of the world, I'd be pretty stuck up, too.
2. Hemo = blood, thorax = chest. Put it all together, and there you have it.
3. Pneumo = air. I sense a pattern. Pneumothorax might happen if the chest wall and/or lung was punctured. As Connor struggled to breathe, air could get into the space around the lung, collapsing it.
4. Tamponade can refer to both the accumulation of blood around the heart or "the act of using a tampon." Thank you, Taber's Cyclopedic Medical Dictionary.
5. For more on transplantation feel free to peruse the Face/Off! entries from March of 2009.

Sunday, June 14, 2009

TERMINATOR SALVATION - Spoiler Alert #3

The terminator that had Arnold Schwarzenegger's features before they were burned away. Note the sternal and costal pectoralis major fibers still clinging to the left chest and shoulder.

CANT' TAKE THE CREDIT FOR THIS ONE
My husband, the cartoonist, suggested that perhaps Governor Schwarzenegger was one of the unfortunates captured and experimented on by Skynet, in the early years. Despite his history of steroid use, the former Mr. Universe is a healthy specimen for his age. Obviously, humans trust their politicians more than they ought. The machines probably considered him an obvious choice when it came to making a human prototype.

TERMINATED BY THE TERMINATOR
Marcus has a big fight with the metallic core of a terminator that had the visage and physique of the governor of California. The "living tissue" doesn't last long on this particular Terminator. It is flayed off of him in an explosion. Marcus and the faceless Terminator are duking it out in the factory where the girl finds the power cells, by the by.

The Terminator punches Marcus in the chest with enough power to cause his human heart (encased in a metallic superstructure) to go into ventricular fibrillation. (I'm assuming his heart is fibrillating based on what happens next.) Marcus collapses, of course. Ventricular fibrillation is the cause of many massive deadly heart attacks in this country.

Ventricular fibrillation essentially means that the muscle of the heart starts to quiver instead of contracting rhythmically. I believe I've read somewhere that severe trauma to cardiac muscle (such as a crushing blow to the chest) could cause VF. The cardiac muscle cells are still contracting, but the contractions are uncoordinated so blood can't be pushed out of the heart.

Connor is left to fight the Terminator alone. He tries, but the terminator is a Terminator, so it doesn't go well. In desperation, Connor goes to the still form of Marcus and tries to revive him. As is appropriate with ventricular fibrillation, Connor gives Marcus a "precordial thump ... (delivered with a clenched fist raised 10 to 30 cm [about 8 to 12 in.] above the sternum and brought down firmly)(1)."
Image of precordial thump technique from the great blog, Medgadget.com.

The precordial thump doesn't seem to work. No surprise since Marcus' heart is encased in super-hard metal, and Connor is a puny human, not the god he thinks he is. (More on the possible types of metal in a future post.) What is Connor to do? In true MacGyver fashion, he uses the materials at hand.

Connor pulls two electrical cables from the wall of the factory and uses them as a cyborg defibrillator. Ventricular fibrillation is treated by direct current defibrillation(2). We see this in moves all the time. For example, in Casino Royal, Vesper Lynd (Eva Green) defibrillates James Bond (Daniel Craig) after he's been poisoned by digitalis.

Connor gives Marcus a huge jolt of electricity from the cables. I admire this gimmick because it is exactly the kind of thing I might suggest for a movie of this type. Which is not to say that it would work, or that I understand anything about electricity. I'm not sure if Marcus' heart would have remained a lump of raw meat, or if Connor would be smelling barbecue.

If he was a normal person, Marcus' heart would have to be revived within 4-6 minutes in order to prevent brain damage from lack of blood and oxygen to his brain. We assume Connor makes the deadline, Marcus revives and saves the day. However, Marcus can't prevent the terminator from driving a big piece of metal through Connor's chest. The spike appears to penetrate from back to front, and emerges just next to the sternum around ribs 5 or 6.

Even with this wound, Connor can breathe and remain conscious. Here he is escaping to the helicopter with Marcus. He looks pretty good, doesn't he? Very alert, no palor, doesn't seem to be burbling blood...
Next time, ruminations about Marcus' heart.

1. Once again, my bedside Merck Manual, 16th Edition, p 524, comes in handy. Okay, it's not really bedside.
2. Sources vary on the amount of electricity needed to re-establish heart rhythm. According to Merck Online, a fibrillating patient is given a jolt of 120-300 joules. A really interesting article on the history of defibrillators describes an automatic emergency defibrillator as packing a 100 kilowatt punch in its charge, with a quick reverse current at the end. I went to Unitconversion.org to see if I could put joules and kilowatts in context for myself. I got confused trying to figure out volts, joules, watts, etc. I never watch an electrician on TV. I gave up trying to understand this stuff after about 15 minutes. Any help, anyone?