Inventing Iron Man (19 page)

It should seem pretty clear why some serious problems would loom eventually for Tony, given his abuse of alcohol. Alcoholism impairs the function of the nervous system, and the Iron Man suit needs to be connected to a nervous system that works well. At least if the Iron Man is to work well. And that is the whole point of this discussion. It won't work well. One of the things that research has shown is that even when the initial effects of alcohol on cognition and thinking are wearing away, there still remain problems of motor skill performance. That means that, even though someone (like Tony) may be recovering from an alcohol binge and be able to “think clearly,” he would still make movement errors when doing something skilled (which would be anything and everything involving being Iron Man—or any other superhero, for that matter). This is a hugely important issue for performance as Iron Man and raises many concerns. Drinking and driving—whether ordinary vehicles on the road or a fully instrumented robotic suit of armor—do not mix. So far we have used alcohol as an example of a nervous system depressant. Let's look now at the opposite side of the coin—nervous system stimulants.

Just as alcohol is an obvious and widely used example of a nervous system depressant, caffeine is probably the best example of a stimulant regularly in use. Caffeine is used as a stimulant by many, often in the form of coffee or tea drinking. Caffeine has also been used as an aid to help improve physiological ability in sports, that is, as an “ergogenic aid.” What is clear is that caffeine can increase wakefulness and alertness and can help increase performance in endurance exercise events. Caffeine also reduces the perception of how uncomfortable (or painful) or difficult a given exercise activity is. It may also help increase the ability of muscle to produce force during a
contraction. There are some downsides to heavy caffeine use, however, including insomnia and stomach irritability. This is becoming even more of an issue in our society due to the increasing prevalence of caffeinated energy drinks. As Chad Reissig and colleagues at the Johns Hopkins University School of Medicine have pointed out, there is significant concern over the widespread and chronic use of high caffeine beverages. This is particularly the case since there is a strong relationship between high caffeine use and high alcohol use. Many companies have developed alcoholic drinks combined with caffeine. It's possible people who purchase these drinks believe that the caffeine as stimulant will offset the alcohol as a suppressant. So they then engage in things—like driving—that they might not do if they were consuming alcohol alone. But it doesn't really work that way. Jonathan Howland and his collaborators at Boston University compared the influence of beer, beer with caffeine, non-alcoholized beer, and non-alcoholized beer with caffeine on attention and reaction time in a driving simulator. Importantly, the addition of caffeine did not offset the reductions of reaction time and attention found with drinking beer.

Of particular relevance to our discussion of Iron Man is the military aspect of caffeine ingestion and how it affects performance. According to J. Lynn Caldwell and colleagues of the Air Force Research Laboratory, Human Effectiveness Directorate at Wright-Patterson Air Force Base, caffeine has been recognized in military aviation as a “stimulant/wake promoter” and is often used in the form of caffeine gum. Other central nervous system stimulants have been used by the military. In fact, all branches of the U.S. military services endorse the occasional use of dextroamphetamines and methamphetamines. Just so there is no confusion about what these are for, they are often called “go pills.” However, higher doses of these drugs are only sanctioned in situations where the mission would be compromised and in the case of heavy fatigue. Chronic use is not sanctioned due to concern over health risk and due to blunting of the stimulating effect.

A horrific example of the use of stimulants comes from a military tragedy. This is relevant to our Iron Man example of War Machine in order to illustrate how vigilant Rhodey would really need to be. And how terrible the outcome could be if he wasn't. A tragic “friendly fire” accident occurred during the early days of the NATO mission in Afghanistan. This accident has been called the “Tarnak farm incident” based on the location near Kandahar, Afghanistan, and took
place on the night of April 2, 2002. On this night members of the Third Battalion of Princess Patricia's Canadian Light Infantry were conducting a night firing exercise using anti-tank and machine guns at a firing range previously held by the Taliban. During the course of this firing exercise, an American F-16 fighter piloted by the U.S. Air National Guard was returning to base at the end of a ten-hour patrol. They mistakenly believed they were under fire from Taliban militants and took evasive action. They also requested permission from flight control to return fire. Flight control initially advised the F-16 crew to stand by and then subsequently to hold fire. However, despite that, a 227 kilogram (500 pound) laser guided bomb was released and hit the target on the ground. The result was four deaths and eight injuries to the Canadian unit, the worst friendly fire accident the Canadian Forces had suffered since the Korean War.

As a result of this tragic incident, two separate military boards of inquiry were launched, one Canadian, one American. In his book
Friendly Fire
, Michael Friscolanti details an important bit of testimony given by Colonel David C. Nichols. He is on record as stating that “combat aviation is not a science. It's an art.” This is sobering testimony when we consider the tragic results that could occur if the Iron Man armor were misused or if the operator were ill disposed. Now, War Machine possesses armaments and destructive capability that easily would outstrip an F-16 fighter. An important outcome of both tribunals was that pilots were routinely given amphetamines (remember those “go pills,” and yes, they also take “no-go pills” afterward) in order to maintain vigilance on long patrol missions. This was the case on this mission as well. Clearly it is worth considering how much the use of pharmaceuticals to maintain vigilance may impair the ability to make accurate human judgments under stress. Yes, a real F-16 fighter and a fictional Iron Man represent very impressive bits of technology. But they are both subject to the fragile nature of the real human beings piloting and guiding them.

We have looked at all sorts of contraptions to help people walk, run, use their hands, and all sorts of prosthetic devices in our quest to determine whether it is possible to create an Iron Man suit of armor. I do want to touch on another aspect of the suit: whether anything
exists currently that could offer the protection that Tony would need while battling bad guys.

Since Iron Man in the fictional world uses his suit as protection against bomb blasts and all manner of other kinds of explosions, probably the best example in real life is the suits worn for bomb disposal by police services and the military. In addition to the obvious concern for puncture wounds from explosions, an important consideration is the pressure wave associated with the blast. There has been an increase in terrorist and counterinsurgent bombings and improvised explosive devices (IEDs) in military zones such as in Iraq and Afghanistan, which has—unfortunately—provided many more observations on the multiple effects of explosive blasts on the human body. An immediate expansion of gas occurs when an explosion happens. This creates a shock (or “blast”) wave that radiates out from the center of the explosion at supersonic speeds of about 3,000 to 8,000 meters (approximately 9,840 to 26,250 feet) per second. So, the blast wave actually hits things before any shrapnel or debris can get there. Four major classifications of injuries occur in a bomb blast: (1) those caused directly by the blast wave from a detonation, (2) “explosive” injuries from the shrapnel itself, (3) those occurring from the movement of the person or other objects at hand, and (4) injuries such as burns or radiation. Large-scale military explosives are designed specifically to enhance the blast wave. In an open space and with a smaller explosive like those commonly found in an IED, the blast wave effect may be smaller. In any case, an Iron Man suit of armor would need to be able to protect against all of these possibilities. A major issue is the pressurization to protect from the blast overpressure as shown in the top of
figure 7.2
. At the bottom of the figure is an example of the state-of-the-art bomb detonation units. In terms of how the bomb disposal suit looks, we are obviously a long way off from the cool Iron Man armor seen in the recent movies, but not that far off from the look of the original gray armor.

This pressure wave can cause severe damage to the throat, trachea, and lungs, as well as the ears and eardrums. Recently more attention has been given to the other body systems affected by blast waves. Amber Ritenour and Toney Baskin of the Brooke Army Medical Center, in Fort Sam Houston, Texas, have summarized that blast survivors may have eye injuries, rupture of the tympanic membrane (eardrum), lung rupture, intestinal damage, heart damage, and traumatic brain injury. It may be that the so-called shell shock syndrome is related to this. The effect of repeated exposure to blasts is something we will come back to again later on. The bottom line is that internal injuries are hugely important but have been typically underappreciated. An important thing is that the Iron Man suit would have to be pressurized and armored to such an extent that it could protect against the blast wave. In reality, this is a pretty tall order given everything we discussed above about what is currently available.

Figure 7.2. Pressure from a blast wave after a bomb detonation (
A
). Sample of the bulky protective suit worn by bomb disposal teams (
B
). Panel A modified from Ritenour and Baskin (2008); panel B courtesy the 31st Civil Engineer Squadron, U.S. Military.

OK. I have always really liked Iron Man and his adventures in his own comic as well as part of the Avengers. In fact, Iron Man and the Avengers are among my very favorites. But, I have to admit I have never been very keen on the origin story with the chest plate that Tony has to protect his heart from the shards of shrapnel lodged in his pericardium or somewhere. Sadly, it just doesn't make much sense. (And, yes, I do appreciate the irony of picking out just one point to dwell on when we are talking superheroes here. But really, this needs thinking about!) In the spirit of talking about amplifying the body with technology that is actually available, I would like to propose a more plausible—but equally compelling and dramatic—real-life example. Instead of shrapnel near his heart, let's speculate that what Tony has instead is a life-threatening arrhythmia (literally meaning the heart rhythm is off), which means that the intrinsic electrical pacing that causes Tony's heart to contract and to pump blood is not working correctly. As a result of this arrhythmia, Tony's heart beats irregularly either too fast or too slow or with gaps.

The heart is composed of a special kind of muscle cell. There are also some cells called “pacemakers” that have the ability to help trigger muscle contraction without any kind of deliberate command to do so. A whole distributed network of these cells in different parts of the heart has the job of coordinating the contraction of the heart muscle so that blood is pumped effectively. When the first and smaller chambers (the atria) fill up with blood received from the body and the lungs, they contract and push the blood into the larger, stronger chambers called “ventricles.” It is the contraction of the ventricles that pushes the blood from one side of the heart out to the body and from the other side into the lungs. Every time you feel or hear your heartbeat, an entire cycle of filling in the atria, priming the ventricles,
and ejecting blood from the ventricles has taken place. This whole procedure has to be well coordinated to work properly.