Neurotoxicity of Anesthesia in Middle Aged Patients

for the last 20 years, the increasing reports from non-human studies have raised suspicion that general anesthetics may cause neurotoxic changes in the developing brain that lead to adverse neurodevelopmental outcomes later in life.there are several case reports of reversible smell and taste dysfunction following exposure to general anesthesia suggesting a possible relationship between anesthetic agents and olfactory dysfunction. this study is to assess the possible neurotoxicity of sevoflurane,isoflurane,and propofol based anesthesia guided by olfactory changes