I live in a Lifestyle Village and was alarmed when recently two of our younger male residents each (independently) developed severe cognitive decline (a form of dementia) after his orthopaedic surgery. Before his operation, each man had been socialising and completely competent but after his operation, each had to be moved into fulltime care! I had never heard of such a severe response to surgery before, so decided to research the medical literature.
Orthopaedic surgery, including common procedures like hip and knee replacements, is a lifeline for many of older adults struggling with mobility issues. However, postoperative cognitive decline (POCD) can be a reasonably common side effect that I think needs a great deal more exposure and discussion!
This mental decline can not only significantly affect a person’s recovery but the quality of the rest of their life! Extensive research shows that cognitive decline after surgery is quite common in older patients, with some studies showing that as many as 25% of elderly patients experience cognitive changes after surgery! The changes can be temporary or, in more severe cases, lead to long-term and severe cognitive impairment as in our two residents.
Here I will explore the recognised risk factors, potential causes, and strategies to manage cognitive decline following orthopaedic surgery in older people.
What is Postoperative Cognitive Decline (POCD)?
POCD refers to a decline in cognitive abilities such as memory, attention, and decision-making that occurs after surgery. It is particularly prevalent in older adults who undergo major surgeries like orthopaedic procedures. Although mild cases may resolve within weeks, some individuals experience long-lasting cognitive issues that severely impact the rest of their lives! POCD is most associated with hip or knee replacements, but it can occur after any surgery, especially those that require general anaesthesia. The cognitive effects can range from mild confusion to full-blown delirium or even long-term dementia or dementia-like symptoms as in our two residents.
Why Does Cognitive Decline Occur After Surgery?
The precise causes of POCD remain unclear, but several factors may contribute to cognitive decline following surgery, particularly in older patients:
Age-Related Brain Changes
Older adults are more vulnerable to POCD because aging naturally leads to changes in the brain. Reduced blood flow, fewer neurons, and slower cognitive processing can make the brain more susceptible to the effects of surgery and anaesthesia.
Anaesthesia
While anaesthesia is generally safe, certain types, particularly general anaesthesia, can influence brain function, especially in older patients. Anaesthesia may increase inflammation or have lingering effects on the central nervous system, contributing to cognitive dysfunction. Some studies suggest that spinal anaesthesia may present a lower risk of cognitive decline than general anaesthesia, but the difference is slight and not always statistically significant [1]. So, anaesthesia might not be the primary cause?
Inflammation and Stress
The stress of surgery itself triggers an inflammatory response, which is believed to play a major role in POCD. Inflammation, especially systemic inflammation, can affect the brain and may exacerbate underlying cognitive decline. Oxidative stress and inflammation are known to cause damage to neurons, which could potentially contribute to long-term cognitive issues.
Pre-existing Health Conditions
Older adults often have comorbid conditions like diabetes, cardiovascular disease, or early signs of dementia, all of which increase the risk of cognitive decline after surgery. These health conditions, combined with the physiological stress of surgery, can make the brain more vulnerable.
Postoperative Delirium
Delirium is a common complication following major surgeries in older adults. While it is often temporary, delirium can increase the likelihood of long-term cognitive decline. It’s characterized by confusion, disorientation, and sometimes hallucinations, and it often results from the combined effects of anaesthesia, pain, infection, or medications.
How Can Postoperative Cognitive Decline Be Prevented or Managed?
Although there is no surefire way to prevent POCD, several strategies can reduce the risk and help older adults recover more effectively from surgery.
Preoperative Assessment
A thorough preoperative cognitive assessment is critical, particularly for patients at high risk of cognitive decline. Identifying patients who may have early signs of dementia or other cognitive impairments allows healthcare providers to tailor perioperative care to minimize risks.
Choosing the Right Type of Anaesthesia
While general anaesthesia is commonly used for orthopaedic surgeries, studies suggest that spinal anaesthesia may reduce the risk of POCD especially in older patients. However, the difference is subtle and not always significant, as other factors, such as the stress of the surgery itself, likely play a more critical role [2].
Minimizing Surgical Stress
Reducing the overall stress of the surgery can help mitigate cognitive decline. This includes minimizing the duration of surgery, using minimally invasive techniques when possible, and managing blood pressure and oxygen levels during the procedure. The use of less invasive surgical approaches may reduce tissue trauma and inflammation, potentially lowering the risk of cognitive impairment.
Postoperative Care
Early mobilization after surgery is vital for reducing the risk of cognitive decline. Encouraging patients to get moving soon after surgery helps maintain circulation, reduces inflammation, and promotes faster recovery. Additionally, cognitive stimulation—such as conversations with family members, puzzles, or other activities—can help keep the brain engaged during the recovery process.
Nutritional Support – the role of Glutathione in reducing ageing and improving brain health
Ensuring proper nutrition after surgery is essential for cognitive recovery. Nutrients that support brain health, such as omega-3 fatty acids, antioxidants, and vitamins, may aid in cognitive function. In some cases, healthcare providers may recommend supplementation with antioxidants like N-acetylcysteine (NAC), which boosts levels of glutathione, a powerful antioxidant that helps combat inflammation and oxidative stress in the brain. Foods that are especially rich in Glutathione include broccoli, spnach, avocados, asparagus and garlic.
While NAC and other antioxidant supplements show promise in reducing cognitive decline, more research is needed to determine their exact role in postoperative recovery, particularly in older patients. However, focusing on a balanced diet rich in brain-boosting nutrients, both before and after surgery, is an easy and effective approach to supporting cognitive health during recovery.
Managing Pain and Medication
Pain management is crucial in preventing delirium and cognitive decline. Opioid medications, while effective for pain, can contribute to confusion and delayed cognitive recovery. Whenever possible, doctors should consider alternative pain management strategies, such as regional blocks, acetaminophen, or non-steroidal anti-inflammatory drugs (NSAIDs), to reduce the risk of delirium and POCD.
What Are the Long-Term Effects of POCD?
For many older adults, cognitive decline after surgery is temporary. However, for some, the effects can persist and lead to lasting cognitive impairment or even accelerate the onset of dementia. The risk is particularly high for those who already have mild cognitive impairment (MCI) or other neurodegenerative conditions.
Long-term effects of POCD can include:
– Persistent memory problems
– Difficulty concentrating or processing information
– Reduced ability to perform daily activities independently
– Increased dependency on caregivers
Why Monitoring is Crucial
After surgery, patients should be monitored for signs of cognitive dysfunction, particularly in the first few weeks or months. Early intervention and tailored rehabilitation can help mitigate the impact of POCD and aid in faster recovery.
Conclusion: The Importance of Preventing Cognitive Decline
While orthopaedic surgery provides significant benefits for older adults, it is crucial to recognize and address the potential risks of cognitive decline. Understanding the factors that contribute to postoperative cognitive dysfunction—such as anaesthesia type, surgical stress, and preexisting cognitive conditions—can help healthcare providers take proactive measures to reduce risk.
Preoperative assessments, careful management of anaesthesia, and tailored postoperative care are key strategies to minimize the impact of POCD. Additionally, nutritional support and early mobilization can aid in a quicker recovery, helping older patients regain their independence and quality of life after surgery.
As research continues to evolve, new treatments and interventions—such as NAC supplementation—may offer promising options for preventing or reducing cognitive decline following orthopaedic procedures.
References:
- Evered, L., Silbert, B., Knopman, D. S., et al. (2018). Recommendations for the nomenclature of cognitive change associated with anaesthesia and surgery—2018. The Lancet Neurology, 17(9), 731–740. https://doi.org/10.1016/S1474-4422(18)30235-7
- Monk, T. G., Weldon, B. C., Garvan, C. W., et al. (2008). Predictors of cognitive dysfunction after major noncardiac surgery. Anesthesiology, 108(1), 18–30. https://doi.org/10.1097/01.anes.0000296071.19434.1e
Please contact Dr Judy Ford at https://drjudyford.com for further information or other requests.