Breast enlargement surgery involves a general anaesthetic. Again, as with any surgical procedure, there are several risks associated with anaesthesia.
The risks of permanent or long lasting damage resulting from anaesthetic drugs in modern day surgery are very low. Otherwise only surgical procedures that were absolutely necessary would be performed. Cosmetic surgery would not be a reality. On a separate note, the risk of being affected in the short term by anaesthetic drugs is much higher. In fact it is almost certain that you will experience dizziness and some discomform immediately afterwards and sometimes nausia.
The anaesthetics used may affect different patients in different ways. This is one of the main reasons medical staff ask many questinos beforehand in order to assess your suitability and the risks.
During anaesthesia, the whole body, brain heart and lungs are affected. It is prudent to point out the risks of anaesthesia: arrhythmia, increased/decreased blood pressure, rapid increase in body temperature, breathing difficulty, heart attack or stroke and even death. Serious complications and effects are rare, especially in people who are generally healthy. You must inform your surgeon and the medical staff of your medical history and allergies before surgery. They will then be able to inform you of the risks appropriate to your own personal medical history.