Aortic replacement for thoraco-abdominal aneurysms remains a major cha
llenge in vascular surgery. Related symptoms, maximal diameter > 6 cm,
progression, aneurysm sac containing none or excentric thrombi and un
controllable hypertension are factors in favour of surgery, if the gen
eral condition of the patient allows the operation. Patients with aneu
rysms < 5 cm maximal diameter, tube-size aneurysms, heavy calcificatio
n of the aortic wall, concentric thrombi within the aneurysmal sac and
significant cardiopulmonary risks should be treated conservatively. P
atients in good general condition with aneurysms around 5 cm maximal d
iameter should be controlled by computed tomography in 6 to 12 months
intervals and in the case of progression surgery can be recommended de
spite missing symptoms. Crawford developed the ,graft-inclusion-techni
que', which combines the ,ingraft'-technique with reattachment of rena
l, visceral and segmental arteries. The ,clamp and repair' principle i
s used in patients with sufficient cardiac function. Otherwise shunt o
r left sided heart bypass are used to reduce cardiac afterload. Accord
ing to the literature local cooling (flush perfusion), cytoprotective
drugs and numerous methods to maintain or ameliorate distal aortic per
fusion during clamping ischemia have been used in patients successfull
y for prevention of ischemic spinal complications. In physiological se
ttings these methods may prove valuable, but under pathophysiological
conditions of TAAA-repair one must doubt the efficacy, because the ind
ividual risk is difficult to assess. In our hands flush perfusion and
cooling of the kidneys proved to be helpful. In animal experiments we
have shown prolongation of Ischemia tolerance time using eicosanoides
to protect the kidneys and the spinal cord. If shunt or left-sided hea
rt bypass can protect the spinal cord during clamping, is unknown, bec
ause the risk of paraplegia in the individual patient can be known onl
y, if the function of the spinal cord is monitored. We have developed
a spinal neuromonitoring system and found, that only one third of all
TAAA-patients is at high risk to develop paraplegia during aortic clam
ping. The surgeon is guided by continuous recording of spinal evoked s
omatosensory potentials and can adapt the operative technique by early
reimplantation and eventually subsequent separate reimplantation of s
egmental arteries supplying blood to the spinal cord, in order to redu
ce spinal ischemia time. Our results in 260 TAAA-patients are presente
d. In a high-risk population of patients with aneurysms type I-III (Cr
awford's classification) it was possible, to reduce the paraplegia rat
e from 7 to 3.5%, the risk of paraparesis from 15 to 6%, while the ope
rative mortality was only reduced from 19 to 10%.