From the Guidelines
Repeated exposure to general anesthesia can cause adverse effects, including increased risk of mortality, as evidenced by a subanalysis of the IMPROVE trial which showed that patients with rAAA who underwent EVAR with only local anesthesia had lower risk of mortality compared with those who were treated under general anesthesia 1.
Potential Risks of General Anesthesia
The potential risks of general anesthesia include:
- Cognitive effects: Especially in older adults or young children, repeated anesthesia may impact memory or cognitive function.
- Drug tolerance: The body may develop tolerance, requiring higher doses for effectiveness.
- Liver and kidney stress: These organs process anesthetic drugs, and frequent exposure can strain them.
- Increased sensitivity: Some people may develop allergies or sensitivities to anesthetic agents over time.
Anesthesia Techniques
Different anesthesia techniques, such as neuraxial anesthesia and monitored anesthesia care, may have varying effects on patients, with some studies suggesting that neuraxial anesthesia may decrease postoperative pulmonary complications but not influence the incidence of MI or overall mortality 1.
Recommendation
Based on the most recent and highest quality study, it is recommended to carefully consider the risks and benefits of general anesthesia and to explore alternative anesthesia techniques, such as local or regional anesthesia, when possible 1.
Considerations for Repeated Anesthesia Exposure
When multiple procedures requiring anesthesia are necessary, the anesthesiologist and surgeon should work to balance the medical needs with the risks of repeated anesthesia exposure, considering alternative pain management strategies or combining procedures when appropriate to minimize the number of anesthetic events.
From the FDA Drug Label
Published animal studies demonstrate that the administration of anesthetic and sedation drugs that block NMDA receptors and/or potentiate GABA activity increase neuronal apoptosis in the developing brain and result in long-term cognitive deficits when used for longer than 3 hours. Some published studies in children suggest that similar deficits may occur after repeated or prolonged exposures to anesthetic agents early in life and may result in adverse cognitive or behavioral effects
Repeated exposure to general anesthesia may cause adverse effects, particularly in children. The available data suggest that prolonged or repeated exposures to anesthetic agents may result in adverse cognitive or behavioral effects. However, it is not clear if the observed effects are due to the anesthetic/sedation drug administration or other factors such as the surgery or underlying illness 2, 3.
- Key considerations:
- Pediatric patients: may be more vulnerable to the potential adverse effects of repeated exposure to general anesthesia
- Window of vulnerability: believed to correlate with exposures in the third trimester of gestation through the first several months of life, but may extend out to approximately three years of age in humans
- Alternative approaches: should be considered when possible, and the benefits of the procedure should be weighed against the potential risks.
From the Research
Adverse Effects of Repeated Exposure to General Anesthesia
- Repeated exposure to general anesthesia can cause adverse effects, as seen in a study on C57BL/6JRj mice, where repeated isoflurane anesthesia caused short-term mild distress and impairment of well-being, mainly in the immediate postanesthetic period 4.
- The severity of repeated isoflurane anesthesia in C57BL/6JRj mice can be classified as mild, but it ranks higher than single isoflurane anesthesia within the mild severity category 4.
- In adult patients with intellectual and/or physical disabilities, repeated dental treatment under general anesthesia is often necessary, and risk factors such as nutrition can predict the need for repeated treatment 5.
- A study on pediatric dental patients found that cases of prolonged general anesthesia exposure were more likely to occur in patients closer to age three, requiring longer non-throat pack time, and utilizing additional surgical services more often 6.
Factors Contributing to Adverse Effects
- The technique of anesthesia induction can affect the level of exposure to anesthetic gases, with inhaled induction methods resulting in higher concentrations of sevoflurane and nitrous oxide 7.
- The use of certain anesthetic agents, such as isoflurane, can cause changes in behavior and well-being in mice, with female mice being more susceptible than male mice 4.
- Patient factors, such as age, living situation, and nutrition, can also contribute to the risk of repeated general anesthesia, with tube-fed or pureed/liquid food patients being at higher risk 5.
Severity Classification
- The severity of a procedure, including general anesthesia, must be classified as mild, moderate, or severe, according to the EU Directive 2010/63 4.
- Repeated isoflurane anesthesia in C57BL/6JRj mice can be classified as mild, but with a higher ranking within the mild severity category compared to single isoflurane anesthesia 4.