You’re wearing your patient gown, lying on the surgical bed. You’re administered several drugs, either intravenously (through your veins) or inhaled. Now, you’re asked to count down from
You wake up, not remembering if you ever got to 0, but it doesn’t matter; the surgery is already over!
Congratulations! Your surgery was successful! But how did you suddenly find yourself in the recovery room after counting to 7? Doctors medically induced you into a coma, a state where you are unresponsive and unconscious. This procedure in medicine has become extremely revolutionary and continues to evolve as technology advances. Can you guess what it’s called?
That’s right, anesthesia!
There are two types of anesthesia: local and general. Local anesthetics work to block pain signals to a region of your body (1). They bind with proteins in a neuron’s cell membrane to create an electrical blockade that prevents protons from entering inside the membrane, inhibiting nerve impulses and ultimately, pain signals reaching the central nervous system in the brain (2, 4). A popular local anesthetic is Novocain which is used in oral operations. Fun fact: another local anesthetic is actually cocaine, but doctors more often use drugs with similar structures rather than cocaine itself (4).
On the other hand, general anesthesia, which is the one I described in the example above, renders patients to lose all awareness and memory while under anesthesia. The earliest forms of general anesthetics include diethyl ether (C2H5)2O and chloroform CHCl3, but these drugs were very hard to control the dosage (1, 4). Now, anesthesiologists combine various gases such as nitrous oxide NO (also known as laughing gas), isoflurane C3H2ClF5O, sevoflurane C4H3F7O, and desflurane C3H2F6O (1). Inhaling these drugs can affect the patient’s breathing which is why patients are also intubated to help stabilize their breathing (1).
We have yet to fully understand how anesthesia works. However, there is a general theory that explains how the anesthetics dissolve in the lipid environments of the cell membranes, affecting the ion channels and neurotransmitter receptor proteins – similar to how local anesthetics create an electrical blockade (2). Since general anesthetics are typically a mixture of various gases, each molecule stimulates a different response to various sites of neurotransmission, explaining why patients under general anesthesia undergo analgesia (inability to feel pain), amnesia, and immobility (3).
Despite the wonderful capabilities that these powerful drugs have on our bodies, there are still several risks and side effects to using them. Don’t let this fact scare you for two reasons: anesthesia is overall extremely safe and older adults or patients undergoing long procedures will be most prone to these risks. These risks include postoperative confusion, heart attacks, pneumonia, and stroke (3). Some people with certain conditions such as obstructive sleep apnea and diabetes will also be more prone to these risks.
Some will even experience the side effects of the anesthetics post-surgery: temporary confusion and memory loss, dizziness, nausea, and more. These side effects are not long-term either, further proving that anesthesia is indeed extremely safe.
But you could be that 1 out of 19,000 patients who succumb to unintended intraoperative awareness (3). It’s just as how it sounds like; you are aware during your operation. This awareness happens while you should be removed of all sensations, but some cases have shown that patients can feel pain (yikes!) (3). Since all the muscles have relaxed, patients are incapable of alerting the doctors in the room that they are still aware! Worst of all, they will experience tugging, stitching, pain, choking, and other sensations, resulting in long-term psychological traumas (3). Because there are so few unintended intraoperative awareness cases, doctors and researchers still don’t know what the cause is for this phenomenon.
Nonetheless, anesthesia is extremely important in the medical field. Without it, there would be far more deaths and people feeling unbearable pain. Perhaps in the near future, we’ll discover more forms of anesthetics or learn more about the modern aesthetics and how to control them to prevent these risks and side effects.