aneurysm rupture during aneurysm clipping managed?
Intraoperative aneurysm rupture may be
catastrophic if not properly managed by the surgeon and anesthesiologist in a
coordinated effort. Unless bleeding is controlled, the outcome is inevitably
fatal. Therefore, the first priority is to permit the surgeon to visualize the
rupture site and clip it.
If the arteries feeding the aneurysm have been
previously dissected and exposed, the surgeon may need only apply temporary
clips to these vessels. Thereafter, he can place a permanent aneurysm clip and
then remove the tempo-rary clips.
Under challenging circumstances, the
anesthesiologist will be required to induce hypotension very rapidly and
profoundly to permit surgical visualization of the ruptured aneurysm.
Typically, a large bolus of intravenous thiopen-tal is administered. Usually
mean arterial blood pressure will need to be lowered well below 50 mmHg before
adequate reduction in hemorrhage is achieved. A bolus of propofol may also
suffice. With aneurysms of the anterior circulation it may be helpful to
manually occlude both carotid arteries by reaching under the drapes and
applying direct pressure on the patient’s neck. At our institution we have also
administered intravenous adenosine to induce reversible complete circulatory
arrest following aneurysm rupture. As one would expect, this provides a
completely bloodless field until cardiac activity resumes. In these situations
one must balance the risks of cerebral ischemia against the surgical need to
visualize the cerebrovascular anatomy.