The importance of transesophageal echocardiography during surgery of the thoracic aorta.
OBJECTIVE
To assess left ventricular dimensions and cardiac output during thoracic and thoracoabdominal aortic aneurysm repair.


METHODS
Nine patients undergoing thoracic and thoracoabdominal aneurysm repair using direct cross-clamping without shunt or by-pass were studied prospectively. Prior to, during cross-clamping (XC) and after declamping left ventricular cross-sectional areas were monitored with transesophageal echocardiography. A pulmonary artery catheter was used for measurements of cardiac output with the thermodilution technique.


RESULTS
Cardiac output increased 43% from baseline during XC (p < 0.01) and was still 55% above baseline at declamping (p < 0.05). Left ventricular end-systolic inner area was reduced 32% during XC (p < 0.01). Pulmonary artery pressures and central venous pressure increased during declamping (p < 0.05). Heart rate increased 38% from 66 beats/ min to 92 beats/min (p < 0.01) and was still 30% elevated at declamping (p < 0.01).


CONCLUSIONS
During thoracic aortic XC, cardiac output is increased and left ventricular end-systolic dimension is reduced. TEE is a valuable supplement to pressure measurements for the evaluation of cardiac function during surgery of the thoracic aorta.
Aadahl
P
P
Department Anaesthesiology, University Hospital of Trondheim, Norway.
Saether
O D
OD
Aakhus
S
S
Bjørnstad
K
K
Strømholm
T
T
Myhre
H O
HO
D000368:Aged; D017542:Aneurysm, Ruptured / Q000601:surgery; D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D017545:Aortic Aneurysm, Thoracic / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D001794:Blood Pressure / Q000502:physiology; D002302:Cardiac Output / Q000502:physiology; D017548:Echocardiography, Transesophageal; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000401:mortality; D011446:Prospective Studies; D011651:Pulmonary Artery / Q000503:physiopathology; D015996:Survival Rate