A new study, facilitated by the City, University of London, warns that using general anesthetic during surgery can lead to brain damage. This may be why many people struggle to return to work after an operation. One potential side effect of administering an anesthetic during an operation is hypoxic brain damage (insufficient supply of oxygen to the brain). Symptoms can include high blood pressure, confusion, and wheezing. It is estimated that this can affect one in every five individuals. Moreover, this new study suggests that the damage to the brain may be more extensive than previously believed.