Your lungs are awesome. They magically make you breathe to regulate a precise balance of oxygen and carbon dioxide, among several other jobs critical to life. They do this despite your best efforts to overcome this balance. The lungs even have a super secret stash of air that is used only in emergencies. In fact, it is very difficult to access this stash. In order to access it, you have to stop breathing.
I’m not talking like hold your breath stop breathing, but chemically induced apnea stop breathing. When someone is given a drug that shuts off the breathing center in the lungs and the brain, the body quickly uses the available oxygen and, if needed, opens the secret stash called the functional residual capacity (FRC) to stay alive.
Interestingly enough, the air we breathe in (and the air in the FRC) is only about 21 percent oxygen and the average adult uses about 3-4 mL of oxygen/kilogram/minute to maintain an adequate oxygen level. So the average 150-pound person needs about 280 mL of oxygen/minute. Now, the secret FRC lung vault can hold about 2 liters of air. So, 21 percent of 2 liters is 420 – this means that right now, your FRC has 420 mL of available oxygen should you receive a lethal dose of Propofol. Knowing that you need approximately 280 mL of oxygen, this would give you about (420/280 = 1.5) one and a half minutes before the oxygen level in your blood starts to drop.
Still with me? If you need to take a break and grab a drink or something, I understand. We haven’t got to the awesome part yet…
Upon inducing anesthesia, we frequently induce apnea and take over the respiratory system. We do not often tell our patients that we will administer a lethal dose of Propofol in order to induce apnea. We say that you (the patient) will fall asleep and you will wake up. Let’s be honest, you don’t care about the details, you just want to be out…
Anyway, we understand how to monitor and manipulate the FRC for everyone’s benefit. As I have just explained it would take around a minute and a half of not breathing before we see any changes on the monitor. It really shouldn’t take longer than that for your CRNA to take over your breathing and start to mechanically deliver oxygen in order to sustain life. There are several techniques and tools that we learn to use to do this most efficiently, and it is awesome. But… things don’t always go smoothly. The real trick is understanding or predicting the patients who are at greater risk than normal and preventing those bad situations, giving yourself the best possible chance for success and safety.
At this point, I feel that I should tell you that anesthesia is very safe and that this is precisely what anesthesia providers have been trained for, and it really is what we do everyday, several times a day… If you asked me to analyze some data about marketing or customer satisfaction and present it to a board of anybody, I would be terrified…
Now, there is a very simple practice called pre-oxygenation that your CRNA can use in order to make sure that you are safe and that your oxygen level remains perfectly within the happy brain zone. Earlier we learned about how the air (and the FRC) contains 21 percent oxygen. Prior to surgery, your CRNA will put a mask on your face and have you take several deep breaths of 100 percent oxygen. Filling your lungs (and your FRC) with 100 percent oxygen has some amazing consequences. Lets do more math… here comes the awesome part…
As mentioned above, your FRC at 21 percent gives you 1.5 minutes of high oxygen levels. If you fill your FRC with 100 percent oxygen, you get 2000 mL or oxygen (instead of air). Knowing that you need 280 mL or oxygen/minute to keep levels up, math tells you that you theoretically get (2000/280 = 7.1) 7 minutes before your oxygen levels will drop.
Yes, you could shut your lungs down for more than 7 minutes before your oxygen levels even start to decrease. That means that after pre-oxygenation, I could give you a drug that would stop you from breathing, leave the O.R., walk down the hall to the cafeteria, grab a doughnut, sit and eat the doughnut, walk back, wash my hands, and come back into the O.R. before your oxygen levels drop.
Now, of course there are disease processes and several conditions that alter this, and I am simplifying things, but the basis remains true. One and a half minutes of safe oxygen levels versus 7 minutes of safe oxygen levels is very significant. And all this due to the simple means of applying a mask for a few moments before surgery… such a simple thing can greatly increase a patient’s safety and security.
So… What does this have to do with anything that belongs on this blog?
In Alma 49, we learn about the city of Noah: “the city of Noah, which had hitherto been a weak place, had now, by the means of Moroni, become strong, yea, even to exceed the strength of the city Ammonihah.”
What are the means of Moroni? He used simple means: dirt, sticks, and rocks to create great things: impenetrable forts. These provided safety and security to his people. But more than that, Moroni “had been preparing the minds of the people to be faithful unto the Lord their God” (Alma 48:7). Faith and trust in the Lord was the true strength of Moroni’s armies.
Our simple means include the primary answers…
Daily scripture study is a simple process that plays a crucial role in keeping us safe and secure against the adversary. It brings strength and inspiration in times of need. Church attendance and partaking of the sacrament is a simple way to fill your spiritual FRC with 100 percent goodness. Like pre-oxygenation, prayer does not have to take hours to be affective. The blessings of simple obedience are endless. Let’s invest our time and trust in the basics. After all, by small and simple things are great things brought to pass (Alma 37:6).
Colby Alexander said:
I have seen very long minutes of apnea (not breathing) and can vouch for this concept. I also knew deep in my heart, that Moroni was a CRNA. I just knew it. And he did anesthesia with herbs, and sticks, and mud.