Can Anesthesia Cause Brain Damage?

Serious complications from general anesthesia, such as brain injury, are rare but can happen. Type and length of surgery, along with the patient’s age and overall health, are major factors affecting a patient’s risk for developing these issues.

Older adults are more prone to postoperative cognitive disorders, such as delirium and cognitive dysfunction. These problems can linger for a while, but permanent brain damage is rare. Likewise, young children may be more vulnerable to lengthy and repeated anesthesia exposure.

General Anesthesia Complications.

Drugs used in general anesthesia are strong sedatives. They induce unconsciousness, stop pain, and suppress other reflexes necessary for surgery. Sedatives also cause respiratory depression (slow, shallow breathing) and affect blood pressure.

Anesthesia providers closely monitor patients’ breathing and vitals, so they can address problems quickly. When serious complications do occur, they typically arise from issues with oxygen delivery, blood flow, or adverse drug reactions.
Here are the major anesthesia complications that can cause brain damage (or death):

Hypoxia.

• Inadequate Oxygen Supply: Failure to maintain oxygen levels during surgery can result in brain hypoxia.
• Airway Obstruction: Issues such as difficult intubation, bronchospasm, or aspiration can block the airway and reduce oxygen supply.

Hypotension.

• Inadequate Blood Flow: Low blood pressure during anesthesia can reduce blood flow to the brain, leading to brain injury.
• Cardiac Events: Anesthetic drugs can sometimes cause severe bradycardia or cardiac arrest, leading to insufficient blood flow to the brain.

Stroke.

• Ischemic Stroke: Immobility and cardiovascular effects from anesthesia can cause blood clots. A clot can travel to the brain cutting off blood supply.
• Hemorrhagic Stroke: Fluctuations in blood pressure during surgery can put pressure on weak blood vessels. This can potentially lead to bleeding in the brain.

Adverse Drug Reactions.

• Malignant Hyperthermia: A rare, life-threatening condition triggered by certain anesthetic agents, leading to a rapid increase in body temperature and severe muscle contractions. It can result in brain damage if not treated promptly.
• Allergic Reaction: severe reactions such as anaphylaxis can lead to hypoxia, hypotension, and impaired blood flow to the brain.

Many of these complications can also occur after surgery and from residual anesthesia effects. These include cardiac events and stroke. Opioids given for pain after surgery increase the risk of hypoxia from respiratory depression.

Postoperative Neurocognitive Disorders.

Patients often experience drowsiness or confusion after surgery. This is usually temporary.

In some cases, patients may develop more serious cognitive impairments. These are known as postoperative neurocognitive disorders (PND).

Age is a major risk factor for PND; It is common after surgery in older adults. ICU patients, patients with pre-existing cognitive issues, and those undergoing more invasive surgeries are also at higher risk of developing these complications.

Postoperative Delirium.

Patients may develop acute symptoms of confusion and agitation after surgery called postoperative delirium (POD). These symptoms can come on suddenly and fluctuate over time.

Postoperative delirium is often associated by multiple factors. These include:

• Effects of residual anesthetics and other medications.
• Brain inflammation and stress.
• Electrolyte or hormonal imbalance.
• Dehydration.
• Hypoxia.
• Infections.
• Sleep deprivation.
• Unfamiliar surroundings.
• Pain and discomfort.

POD usually resolves within a week of surgery. It can be serious, however, and is associated with longer hospital stays. It is also associated with higher risk of other complications including postoperative cognitive dysfunction.

Postoperative Cognitive Dysfunction.

Patients may also develop more general problems thinking or “brain fog” after surgery. This condition is called postoperative cognitive dysfunction (POCD). POCD is often gradual and improves over several weeks or months. A small number of patients may experience permanent cognitive decline.

The exact cause of POCD is not fully understood. Recent research suggests brain inflammation resulting from both surgery and anesthesia may be a primary factor in many cases.

Anesthesia & Children’s Brain Development.

Several animal studies have shown negative effects of anesthesia exposure on brain development. This has led to further research into its effects on children.

Recent studies suggest that prolonged or multiple exposures to anesthesia in children are associated with a modest increase in developmental issues. In 2016 the FDA issued a warning that repeated or lengthy use (3+ hours) of anesthesia in children younger than 3 years or in pregnant women during their third trimester may affect children’s brain development.

However, a single, brief exposure to anesthesia is unlikely to cause long-term negative effects.

This should not deter children and pregnant women from having procedures that are medically necessary. If left untreated, serious medical issues can pose greater risk to health and development than anesthesia. Parents and caregivers are encouraged to discuss the risks, benefits, and timing of surgery and procedures requiring anesthetics and sedative drugs with their child’s healthcare provider.