If you are asking if its a physical or chemical change it would be physical.
Included in the algorithm are critical time goals set by the National Institute of Neurological Disorders (NINDS) for in-hospital assessment and management. These time goals are based on findings from large studies of stroke victims:
Immediate general assessment by a stoke team, emergency physician, or other expert within 10 minutes of arrival, including the order for an urgent CT scan
Neurologic assessment by stroke team and CT scan performed within 25 minutes of arrival
Interpretation of CT scan within 45 minutes of ED arrival
Initiation of fibrinolytic therapy, if appropriate, within 1 hour of hospital arrival and 3 hours from onset of symptoms. rTpa can be administered in “well screened” patients who are at low risk for bleeding for up to 4.5 hours.
Door-to-admission time of 3 hours in all patients
The Femoral Head would be the other bone.
C. From what I have read they come from the outdoors.
