Nt. Kouchoukos et al., HYPOTHERMIC BYPASS AND CIRCULATORY ARREST FOR OPERATIONS ON THE DESCENDING THORACIC AND THORACOABDOMINAL AORTA, The Annals of thoracic surgery, 60(1), 1995, pp. 67-77
Background. Hypothermic cardiopulmonary bypass with intervals of circu
latory arrest is a useful adjunct during operations on the descending
thoracic aorta and distal aortic arch when severe aortic disease precl
udes placement of clamps on the aorta. Hypothermia also has a marked p
rotective effect on spinal cord function during periods of aortic occl
usion. Methods. Fifty-one patients (age range, 22 to 79 years) with de
scending thoracic or thoracoabdominal aortic disease had resection and
graft replacement of the diseased aortic segments using hypothermic c
ardiopulmonary bypass and intervals of circulatory arrest in situation
s where the location, extent, or severity of disease precluded placeme
nt of clamps on the proximal aorta (8 patients) or (in 43 patients) wh
en extensive thoracic (11) or thoracoabdominal (32) aortic disease was
present and the risk for development of spinal cord ischemic injury a
nd renal failure was judged to be increased. Patent intercostal (below
T-6) and upper lumbar arteries were attached to the graft whenever po
ssible. Results. Thirty-day mortality was 9.8% (5 patients). Paraplegi
a occurred in 2 and paraparesis in 1 of the 46 30-day survivors (6.5%)
. Among the 27 operative survivors with thoracoabdominal aneurysms, pa
raplegia occurred in 1 of 12 with Crawford type I (8%), 0 of 10 with t
ype II, and 1 of 5 with type III aneurysms (20%). Paraplegia occurred
in none of the 12 patients with aortic dissection and in 2 of the 15 p
atients with degenerative aneurysms. Renal failure requiring dialysis
occurred in 1 (2.2%) of the 46 30-day survivors. Conclusions. Hypother
mic circulatory arrest is a valuable adjunct for the treatment of comp
lex aortic disease involving the aortic arch and thoracoabdominal aort
a. In patients with thoracoabdominal aneurysms, its use has been assoc
iated with a low incidence of renal failure and an incidence of parapl
egia/paraparesis in traditionally high-risk subsets (type I and II ane
urysms, aortic dissection), which may be less than that observed with
other surgical techniques.