The causes of systemic secondary insult to injured brain include all of the following except

Presumably, extreme hypercapnia produces more severe cardiovascular depression than is seen in animals subjected to lesser degrees of hypercapnia; the cardiovascular depression, in turn, leads to greater cerebral ischemia and ultimate brain damage. Prolonged hypoxia induces neuronal cell death apoptosis, resulting in a hypoxic brain injury. Cases of total oxygen deprivation are termed "anoxia", which can be hypoxic in origin (reduced oxygen availability) or ischemic in origin (oxygen deprivation due to a disruption in blood flow Emerging evidence suggests that, contrary to standard teaching, isolated brain injury may be associated with hypotension. RESULTS: The cause of hypotension was hemorrhagic in 113 (49%), isolated brain injury in 30 (13%), neurogenic in 14 (6%), and other causes in 24 (10%). Fifty (22%) were indeterminate. Ref Harrison20th edition pg 2234