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The Hidden Dangers of Anesthesia

Surgery is a stressful and costly yet necessary event for millions of Americans each year, requiring the use of anesthesia. Most people know that anesthesia is used to numb the body so that the patient does not feel pain during the procedure. What you may not realize is that there are a number of side effects associated with anesthesia. Most of these side effects last from a few days to a couple of weeks.

There is, however, a potentially dangerous side effect that most people are unaware of — post-operative delirium. Susan Baker, a professor at the Johns Hopkins Bloomberg School of Public Health, recalls a frighteningly vivid hallucination she had while recovering from surgery. While lying in her bed, she saw a fire burning down the hospital and had to call the nurses’ station in order to receive help. “It was the most terrifying experience I have ever had,” she said.

The Different Types of Anesthesia

There are three different types of anesthesia. The distinction is important because side effects will vary depending on what type of anesthesia you undergo.

Local Anesthesia

Local anesthesia is the mildest form of anesthesia. Numbing a small part of the body, it is used during minor surgery or procedures such as a routine dental work or getting stitches on your finger. Local anesthesia generally has minimal side effects, including:

  • Mild bruising, redness, itching or swelling
  • Nausea
  • Mild dizziness
  • Prolonged numbness

Regional Anesthesia 

Regional anesthesia involves numbing larger parts of the body. Examples of regional anesthesia include an epidural or a spinal block. Side effects can include:

  • Headache
  • Minor back pain
  • Difficulty urinating
  • Hematoma (abnormal collection of blood outside of a blood vessel)

General Anesthesia 

General anesthesia refers to being sedated through either inhaled or intravenous medications. The patient remains unconscious throughout the procedure. General anesthesia is used in major surgery and has the most side effects of the three anesthesia types. These include:

  • Nausea and vomiting
  • Sore throat
  • Confusion
  • Muscle aches
  • Itching
  • Hypothermia
  • Delirium
  • Cognitive dysfunction

Postoperative Delirium 

Those with postoperative delirium can experience confusion, memory loss and vivid hallucinations. Patients often do not remember where they are or why they are in the hospital. Physicians have been aware of postoperative delirium since the 1980s and hypothesized that it results from the stress associated with undergoing surgery. However, new studies now suggest that anesthesia plays a role in postoperative delirium and that the higher the dose, the more likely a patient is to experience delirium. Researchers believe that the condition can be more dangerous than previously thought. The attention and memory deficiency, for instance, can last for months and, in some cases, years.

Delirium tends to be more common after major surgeries. One study found that 50 percent of patients over the age of 60 become extremely disoriented after heart bypass or valve replacement surgery. Now that research supports the correlation between anesthesia and delirium, scientists are concerned about the dosage of anesthesia patients receive. In a study done by Frederick E. Sieber, patients who underwent general anesthesia experienced delirium at twice the rate than those who had local or regional anesthesia.

In another study examining the long-term effects of delirium, Jane Saczynski monitored the mental status of patients 60 and older for one year after a heart bypass or valve surgery. Patients who didn’t experience delirium regained their normal mental capabilities in about a month, while those who did experience postoperative delirium required six to 12 months to return to normal mental function. Currently, the only recommendations to help prevent postoperative delirium is to stop the use of medications that might affect brain activity and have patients’ friends and family visit them frequently.

It is important for the medical community to continue investigating the side effects associated with anesthesia and the long-term impact it can have on patients. As we learn more about the implications of using anesthesia, patients can help protect themselves from the potential side effects by exploring non-surgical treatment options.


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