Why Should You Care About Anesthesia…You’ll be asleep anyway right?

Question. What traits are shared by these two jobs: Airline pilot, and anesthesiologist? This comparison is made frequently, and the analogy is intuitive. A pilot’s adventure follows the arc of

1. Preparation
2. Take-off
3. Cruising
4. Landing.

This maps neatly onto my daily routine of

1. Preoperative evaluation
2. Induction of anesthesia
3. Maintenance
4. Emergence.

The analogy extends further, to the years of training necessary to prepare for each job, as well as the responsibility of caring for the lives of others while they are suspended, and unable to take care of themselves. In both cases, we care for people who are often — but not always! — asleep. Finally, both jobs are characterized by long periods of calm watchfulness, potentially punctuated by moments of turbulence and troubleshooting.

Common Questions About Anesthesia

Anesthesia is not hard to explain. In the few minutes we have together before rolling back to the operating room for their nap, my patients ask all kinds of questions. But it turns out there is a small group of core priorities underlying all of the answers.

Why did I have to fast overnight? Do I need a breathing tube? How can an epidural be helpful? Is it ok to use propofol even after the tragedy that made the drug famous? (I’ll answer each of these questions — and hopefully some others — before the end of this article; but for now i’ll let this CNN hyperlink tackle the last one for me http://www.cnn.com/2013/06/21/showbiz/jackson-death-trial/index.html)

I try to make my explanations simple but complete. For example, “Good question Mrs. Marcie. We ask you to fast prior to anesthesia, because it’s safest to have an empty stomach. That way stomach contents have less chance of entering your lungs. I’m so sorry you’re hungry, and I can promise that soon you’ll forget all about it!”

Chances are, each of us will undergo anesthesia at some point in our life. I was been put under once in high school— incidentally by someone who later became one of my professors during training! While some people would rather not know the details of what is being done to their body while they’re unconscious — and there are a great many among us who feel that way — it’s really a preference to not get spooked out, rather than pure disinterest. So I’m hopeful that learning this information from the comfort of your desk makes it easier to absorb and digest calmly. My goals are to relieve some of the anxiety and uncertainty surrounding anesthesia, and to deepen readers’ understanding of the care and consideration their wellbeing receives.

The competing interests of comfort versus safety

One intuitive way to conceptualize anesthesia is the interplay of comfort and safety. The safest patient is a wide awake patient. However, this is never the most comfortable patient. Consider that we each seek and embrace the loss of consciousness every night when we go to sleep. Being conscious is on some level, always less comfortable than being unconscious. After all, when do we experience relief from our chattering mind, reminding us of all our shortcomings and disappointments? When we’re asleep of course! Or intoxicated. Helps explain the popularity of both these pastimes.

Just laying in the preop area, people are already nervous. Many report sleeping very poorly the night before surgery. Understandably, people are worked up over getting surgery, and it doesn’t help to skip coffee, skip breakfast, and then get poked with a needle to start the IV. It’s no surprise that patients wanna get to sleep right away! And we are more than happy to help. There’s just one thing.

An unconscious person, whether asleep on the OR table, or in their bed, is less safe than a conscious person. It’s interesting to note that people can experience different depths of unconsciousness. And the deeper we go, the less safe we are. So when you sleep at night, you lock your door and you’re all set because you’re still close enough to conscious that a break-in or fire at the house will awaken you from the noise or smoke; but when you sleep during surgery, you need a dedicated health care professional at the head of your bed. That’s because unlike normal sleep, you won’t awaken to loud noise, being physically moved, or even being cut. That’s the whole point of course, and that same deep sleep that allows for unconscious surgery also opens the door to all kinds of other hazards.

So putting you to sleep is just the beginning, and it’s the bulk of our training and job to keep you alive, healthy, and motionless while asleep. We stand guard until the surgery is done, you have awoken, and can go back to protecting yourself like we all normally do while awake. Thinking of it this way begs the question of how we protect ourselves while awake.

From head to torso, here are 6 core protective functions we take for granted while awake, and which we more or less lose during anesthesia:

1. eyelids cover and lubricate the cornea,
2. coughing and gagging protect foreign objects from entering our lungs (the violent coughing from a drop of water “going down the wrong pipe”)
3. the swallowing reflex does the same by getting things out of our mouth quickly
4. the lungs breath to supply oxygen and eliminate carbon dioxide
5. the heart and blood vessels provide forward pressure on blood to carry oxygen and carbon dioxide to and from tissues
6. blood vessels also play a central role in regulating body temperature.

So to recap, anesthesia providers balance between the benefits of unconsciousness, and the dangers it poses. We constantly monitor the vital signs of blood pressure, blood oxygen level, heart electrical activity, carbon dioxide expiration, and body temperature. If any of those are out of the healthy range, we use our training and tools to correct them. We have access to your blood through a small plastic tube in your vein (IV line), and this access lets us give you fluid, medicine, or blood products to keep your vital signs and lab values normal while you sleep soundly.

The Two Main Types Of Anesthesia: Regional and General

Of course, not every patient who has surgery goes to sleep. The easiest case to imagine is that you’re wide awake undergoing cesarean section for delivery of a baby. In this case, medicine is given in the epidural or spinal space (through injection between the vertebrae), that renders your body temporarily numb and motionless from the chest down. You’re safer since you’re awake, able to protect your eyes, airway, and continue breathing. Beyond safety, the other attraction of this choice is that childbirth is a life experience that patients uniformly prefer to be awake for, compared to a knee replacement, say. Epidural and spinal anesthesia are two kinds of “neuraxial anesthesia,” and that in turn is a category within “regional anesthesia,” so-called since only a region — in this case the “neuraxis” or spinal cord — is asleep, while you the person are still awake. Other forms of regional anesthesia can just put your arm, leg or jaw to sleep for the surgery.

The more commonly depicted form of anesthesia is called “general anesthesia.” It’s defined by being so deeply asleep that you don’t move when cut, and it comes with all that baggage we discussed earlier. General anesthesia is not defined, as many think, by the notorious breathing tube. Endotracheal intubation carries with it many negative associations, including harrowing ambulance rides, long stays in the ICU, and just the gross thought of gagging on a plastic tube in your throat. But while those images can make the thought of being intubated unattractive, it’s truly a life preserving measure and keeps many people from terrible complications like not breathing, and pneumonia from gut bacteria entering the lungs.

So do you need a breathing tube? Well, it depends on the surgery, and I won’t place one unless it’s totally necessary. If I decide it’s best for your own safety to have one protecting your lungs, I promise you’ll be comfortably asleep and won’t remember any of it.

Now pick out your favorite travel destination, picture the beautiful calming scene, and count down from 100 with me…

TLDR

When asleep, you’re more comfortable — but less safe — than when you’re awake. Under the deep sleep of anesthesia, you can’t arouse to danger, or drink when you’re thirsty, or pee when you gotta go, or blink your eyes when they’re dry, or cough and gag to protect your lungs. At the same time, you’re more likely to get cold, fall out of bed, vomit, and stop breathing. In any combination, in any order. So to get the benefits of unconsciousness while managing the associated risk, you’ll have a vigilant spotter for this incredible dive into unconsciousness, who is highly trained and 100% committed to your wellbeing.

Next up…machine spotters: What would it take for a robot with artificial intelligence to take over part (or all?) of the job?

Spoiler alert! Like airline pilots, much of the anesthesiologist’s job is already done by a machine that is supervised by humans!

That’s it for now. Thanks for reading.