How General Anesthesia Can Affect an Elder’s Mind


As a person ages, the chance that they will need to undergo surgery requiring the use of general anesthesia increases.

General anesthesia describes the combination of intravenous and inhaled drugs used render an individual unconscious and unable to feel physical pain during a surgical procedure. This type of intervention is typically used for surgeries that will take a long time to complete, cause a great deal of physical and mental discomfort, or may interfere with a person's ability to breathe.

The process of "going under" usually doesn't present a problem for younger, healthier individuals. After a few days, any residual feelings of grogginess or confusion typically wear off.

However, as an individual ages, the way their body processes drugs changes and their overall metabolic rate slows down.

"General anesthesia does carry a higher risk for the elderly population," says Damon Raskin, M.D., a board-certified internist and medical director for two skilled nursing facilities. According to Raskin, it takes longer for an older person's body to rid itself of the chemicals involved in anesthesia, which can prolong the negative effects of the drugs.

The situation becomes increasingly complex if the individual also suffers from other health conditions, such as diabetes, heart disease, cancer, etc.

For example, people with Parkinson's disease are more prone to experiencing bouts of confusion and hallucinations that may not appear until days after the surgery was performed. This can have a negative effect on the type of post-operative care these individuals receive, caution experts from the Parkinson's Foundation.

Anesthesia, Delirium and Dementia

When examining the potential cognitive effects of general anesthesia, it's important to first make the distinction between two commonly-confused conditions: delirium and dementia.

While these ailments share similar symptoms—confusion, problems with perception, mood swings and decreased cognition—there is one crucial difference that separates them. Delirium refers to abrupt, temporary changes in a person's mental functioning, whereas dementia describes a more gradual, consistent decline in cognitive capacity.

People with dementia can indeed exhibit signs of delirium, but the two terms are not interchangeable.

Delirium is a common cognitive after-effect of general anesthesia, particularly for the elderly. This has led to a flurry of research studies aimed at determining whether being "put under" can cause permanent brain changes, even dementia.

Results of these investigations have been mixed. In May of 2013, Mayo Clinic researchers published the results of an analysis of nearly two thousand individuals who received general anesthesia after age 45, which failed to uncover a link between the drugs and dementia.

In June of 2013, a group of French researchers presented a different set of findings at the annual gathering of the European Society of Anesthesiology. Study authors claimed that an elder's risk for developing dementia could be increased by as much as 35 percent, if they underwent general anesthesia.

Avoiding Post-op Problems

As a caregiver, it can be hard to know what to do when a senior needs surgery.

The link between dementia and general anesthesia remains fuzzy, but there's no doubt that surgery can cause lingering physical and cognitive issues for older adults.

Post-operative cognitive dysfunction (POCD)—a decrease in cognitive ability that can occur after a significant surgery—is a more common complication for older adults, says Raskin, and its effects can last for months. POCD isn't synonymous with Alzheimer's, or other forms of dementia, but its symptoms can mimic those of more permanent forms of cognitive impairment.

One key to preventing unnecessary problems from surgery is to have your loved one undergo a thorough pre-operative evaluation by their primary care doctor. The surgeons and anesthesiologists who will be involved in the procedure need to be made aware of your loved one's important health information, including:

  • Their medication regimen
    The drugs used during general anesthesia can negatively interact with a number of medications, including beta-blockers (Tenormin, Corgard, Sectral, etc.), oral hypoglycemics (Metformin, etc.) and monoamine oxidase inhibitors (Parnate, Emsam, Marplan, etc.). Blood thinners, another common class of medication taken by the elderly, can also cause problems with bleeding during the procedure. Depending on which prescriptions your loved one is on, their doctor may provide specific instructions for tapering off or stopping certain medications before a surgical procedure.
  • Any pre-existing conditions
    Every medical issue, no matter how seemingly small, can potentially impact your loved one's ability to maintain their health both during and after a surgical procedure. Raskin cautions that urinary tract infections (UTIs) and other infections can cause huge problems during surgery, and should always be disclosed in advance of the procedure. If your loved one suffers from a heart condition, a pre-surgery trip to their cardiologist is also a necessity.
  • All supplements they are taking
    The merits and potential dangers of supplements for seniors are topics of frequent debate among the medical community. But, just like prescription medications, supplements can have disastrous effects when mixed with anesthesia drugs.

The doctor in charge of coordinating your loved one's procedure should make sure this and any other relevant information is communicated to their surgical team. You and your loved one may also meet with the anesthesiologist in person to go over important medical considerations.

Undergoing general anesthesia carries risks for people of every age, but making sure the surgical team is up-to-date on your loved one's health status will reduce the risk of adverse mental side effects.

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Oh, how I can attest to the truth in this article! It is not surprising to see that two studies on this came with different conclusions: although clinical studies are based on only that which can be concisely, accurately documented, there are so many variations inherent in every person, and their reactions to drugs, that it's difficult to come to any final conclusions....there will hopefully be more studies in this! It is desperately needed!

As for my scenario, mom absolutely had to have a 2nd major operation (hip replacement): the first hip replacement had been done with an implanted device that was recalled by the mfr.; this we discovered after mom had suffered 3 hip displacements. We knew she would most likely be worse off mentally afterward and we were correct. Her dementia is profound, she is completely wheelchair-bound, will not even attempt to walk (refused PT almost immediately after the 2nd surgery, got so combative that it was pointless to continue), is completely incontinent and will spend the rest of her life in a nursing home. It is incredibly tragic and sad; difficult to deal with and has radically changed everyone's life in our family.

I applaud every bit of information that this site makes available to caregivers. Knowledge is power!
A "general" .... something that I've always suspected, but now know.
One must weigh the consequences of a general anesthetic, as opposed to suffering from whatever your condiditon is. For example, Cataract surgery will allow one to see ( very important ) as opposed to not having it to save the memory. I'd rather see in my last years.
Maybe it is too obvious (or too risky for Big Pharma profits), but too much anesthetic, like too much alcohol, is clearly not good for the brain, especially in those over 50.

The goal of my non-profit Goldilocks Anesthesia Foundation is to make brain monitoring a standard of care.

Vital signs, like heart rate and blood pressure, only reflect brain stem activity. However, the target of anesthetics is the cortex, the top part of the brain.

Since 1996, we have the ability to directly measure brain response to anesthetics. The BIS may not be perfect but it is the best available technology to avoid routine over medication, the standard practice without this critical information.

To properly inform prospective surgery patients, read 'Getting Over Going Under, 5 things you MUST know before anesthesia.'