By Kenneth Kim, MD

Using general anesthesia has become so standard that patients often fail to weigh its risks for elective procedures. However, the truth is that in addition to several side effects, general anesthesia poses substantial medical risks to both the mind and body. While many are aware of the risk of blood clots during surgery, fewer know about the lesser-known risk of short-term memory loss or dementia.

As a plastic surgeon, I make it my mission to fully inform patients about the side effects and risks linked to general anesthesia. I also make them aware of awake surgery, a safer alternative to elective procedures.

General Anesthesia Side Effects

Though general anesthesia is commonly used in medical procedures, you should be thoroughly informed about its potential side effects—one of the most prevalent of which is postoperative nausea and vomiting. While the exact cause is unknown, it may result from medications, changes in blood chemistry, or the body’s reaction to surgery.After surgery involving intubation, patients may also experience a sore throat and hoarseness due to inserting a breathing tube into the throat. 

Muscle pain and soreness are other symptoms that can occur after receiving general anesthesia. The positioning during surgery, muscle relaxation medications, and prolonged immobility during the procedure can contribute to these symptoms.

Feeling drowsy or groggy after waking up from general anesthesia is another common symptom, as the drugs used during anesthesia can cause temporary cognitive impairment, resulting in confusion or disorientation. These effects are generally short-lived and resolve as the medications wear off.

Patients may sometimes experience temporary memory loss or cognitive issues after receiving general anesthesia. This “anesthesia fog” is typically short-lived and resolves within a few days or weeks, but in rare cases—particularly among the elderly or patients with pre-existing conditions—cognitive decline may persist for longer periods.

General Anesthesia Risks

In addition to the aforementioned side effects, the act of receiving anesthesia carries more serious inherent risks, such as difficulty breathing, allergic reactions, cardiovascular problems, and neurological complications. Moreover, these risks increase with age, existing medical conditions, and the complexity of the surgery.

Although rare, allergic reactions to general anesthesia can occur. This is often highlighted by symptoms including rashes, itching, difficulty breathing, or even anaphylaxis. 

General anesthesia can also affect a patient’s ability to breathe properly. In rare cases, patients experience respiratory complications such as life-threatening pulmonary embolism or respiratory failure. Additionally, some patients may experience fluctuations in heart rate or blood pressure while under general anesthesia. Patients with pre-existing heart conditions are at a higher risk of cardiovascular complications.

Most troubling, however, is when anesthetics pass the blood-brain barrier and cause patients to enter a deep sleep state. Studies have shown that this can damage neurons in the hippocampus—the region of the brain responsible for memory formation. Patients who are placed under general anesthesia for longer than two hours or undergo multiple procedures totaling over two hours risk impaired short-term memory, which is what people rely on to recall new names, recent discussions, and instructions.

Though patients over 65 and very young children are the most susceptible to noticeable short-term memory loss after surgery, no one should be cavalier about the loss of neurons. We all have a large pool of brain cells available during our formative years, but this decreases steadily with age. Even if you don’t notice it right away, general anesthesia depletes your hippocampus’s only supply of nerve cells.

Awake Surgery: Safer Than General Anesthesia

Thankfully, an alternative to elective surgery requiring general anesthesia exists. In recent years, surgeons in Korea have made great strides in improving the safety of elective procedures by using local anesthesia. During cosmetic surgeries like breast augmentations, tummy tucks, rhinoplasties, eyelid surgeries, and facelifts, patients can remain completely conscious and even follow their surgeon’s instructions. Best of all, they experience absolutely no discomfort.

However, general anesthesia still has a place in surgical practice. In cases where patients require surgery due to an emergency, cancer, or trauma, the advantages of general anesthesia almost unilaterally outweigh the potential risks.

Conversely, with non-emergency surgeries, surgeons have ample time to plan before elective operations. Like professional racecar drivers, we study the course and prepare for every eventuality because we understand that nonelective procedures are quite different, and we cannot fully plan for what we might encounter.

Elective surgeries improve patients’ overall quality of life, but their risks must not exceed their benefits. In the case of long-term memory loss or dementia, the potential risk is too high, and we can no longer afford to treat these risks as inevitabilities. 

Patients have two options, with awake surgery and local anesthesia presenting a safer alternative to general anesthesia, offering minimal risk and faster recovery during elective procedures. Being fully informed about the risks and benefits of general anesthesia empowers patients to make confident decisions about their elective procedure.

Kenneth Kim, MD, is a board-certified plastic surgeon, an assistant clinical professor at UCLA, a clinical Instructor at Seoul National University, and a partner of Dream Medical Group in Los Angeles.