Özet
Increasing understanding of the mechanisms of cerebral injury
and physiology of brain protection during operations on the
aortic arch has led to important developments of protective
methods in the last 30 years. Hypothermia is the principal
element of all current methods of brain protection. The limited
time available for safe conduct of the reconstruction under the
conditions provided by deep hypothermic circulatory arrest
was appreciated early on. All other adjunctive methods, i.e.
selective antegrade cerebral perfusion or retrograde cerebral
perfusion were originally developed as an alternative to
circulatory arrest or in an attempt to safely prolong the
duration of the circulatory arrest. Even with the adjuncts of
retrograde cerebral perfusion and to a lesser extent selective
cerebral perfusion, there is a serious time pressure to complete
the operation rapidly in order to limit the period of “total
cerebral protection time”. Surgical steps in the reconstruction
of the aortic arch were modified in response to this essential
requirement. The changes in the conduct of the operation
also involved the sites of arterial inflow for perfusion. The
innovative steps in the reconstruction of the arch and the
changes in the perfusion routes occurred simultaneously
and both had an additive effect in the improved outcome
of these complex operations. The following is a synopsis of
these innovations from a historical point of view followed
by the description of our preferred current technique of arch
replacement which incorporates some of these innovations
and provides continuous antegrade cerebral perfusion and
virtually eliminates any period of interruption of brain
perfusion.