Redesigning Cardiac Surgery to Reduce Neurologic Injury

Neurologic injuries are frequent and devastating complications following cardiac surgery.
Previous work conducted by our research group and others has identified the principal
mechanisms creating both overt and subtle neurologic injuries after cardiac surgery.
Current work by our group has identified that the causes (thrombotic/lipid emboli, cerebral
hypoperfusion & hypotension, and gaseous emboli) of these injuries are byproducts of
processes of surgical and perfusion care. This insight suggests that the redesign of
clinical strategies and techniques to prevent the occurrence of these intraoperative sources
of damage may provide an opportunity to reduce the risk of neurologic injury after cardiac
surgery.

The goal of this research is to identify modifiable clinical strategies and techniques of
surgical and perfusion care associated with the causes (thrombotic/lipid emboli, cerebral
hypoperfusion & hypotension, and gaseous emboli) of neurologic injury secondary to coronary
artery bypass graft (CABG) surgery, and subsequently to redesign these processes to reduce a
patient's risk of a neurologic injury. The following hypotheses will be addressed.

Hypothesis #1a. Identifying alternative strategies for conducting processes of surgical and
perfusion care will reveal opportunities to reduce the occurrence of causes of neurologic
injury. The most common mechanisms creating neurologic injury, whether focal or global,
after CABG surgery are thrombotic/lipid emboli, cerebral hypoperfusion & hypotension, and
gaseous emboli. Processes of surgical and perfusion care are associated with the creation
of each of these causes of neurologic injury.

Hypothesis #1b. Redesigning processes of surgical and perfusion care to reduce
thrombotic/lipid emboli, cerebral hypoperfusion & hypotension, and gaseous emboli during
CABG surgery will result in reductions of tissue-level and neurologic injury. We will
analyze sera for tissue-level brain injury as well as identify any new neurologic injuries
present among patients undergoing CABG surgery. Redesigning CABG surgery to reduce
thrombotic/lipid emboli, cerebral hypoperfusion & hypotension, and gaseous emboli will
result in decreases in tissue-level and neurologic injury.

Hypothesis #2. A regional quality improvement intervention will result in changes to
surgical and perfusion techniques Regional dissemination of the findings from Hypotheses
#1a,b may be realized through focused quality improvement initiatives utilizing
multidisciplinary clinical teams.