During surgery for aoic arch aneurysm under deep hypothermic circulatory arrest, which of the following anesthetic agent administered prior to circulatory arrest that also provides cerebral protection?
Etomidate
Thiopental sodium
Propofol
Ketamine
B i.e. Thiopentone Sodium Surgery from aoic arch aneurysm carries a great risk for hypoxic injury of brain; so surgery is performed using deep hypothermiaQ & circulatory arrest method (based on principle that brain can tolerate circulatory arrest for periods of upto 45 minutes if temperature is lowered to 15-17deg C during surgery. During this process a cerebroprotective agent4 is needed which lowers the metabolic demands of brain by eliminating metabolic cost of electrical activity and protect brain from hypoxia by reducing cerebral edema & free radicle formation. Thiopentone (Barbiturate)Q is definitely a cerebroprotective drugQ Other probable drugs are Etomidate, Propofol, Isoflurane, Ketamine