The impact of hypovolaemic shock on the aortic diameter in a porcine model.
OBJECTIVE
To investigate the impact of hypovolaemic shock on the aortic diameter in a porcine model, and to determine the implications for the endovascular management of hypovolaemic patients with traumatic thoracic aortic injury (TTAI).


METHODS
The circulating blood volume of seven Yorkshire pigs was gradually lowered in 10% increments. At 40% volume loss, an endograft was deployed in the descending thoracic aorta, followed by gradual fluid resuscitation. Potential changes in aortic diameter during the experiment were recorded using intravascular ultrasound (IVUS).


RESULTS
The aortic diameter decreased significantly at all evaluated levels during blood loss. The ascending aortic diameter decreased on average with 38% after 40% blood loss (range 24-62%, p = 0.018), the descending thoracic aorta with 32% (range 18-52%, p = 0.018) and the abdominal aorta with 28% (range 15-39%, p = 0.018). The aortic diameters regained their initial size during fluid resuscitation.


CONCLUSIONS
The aortic diameter significantly decreases during blood loss in this porcine model. If these changes take place in hypovolaemic TTAI patients as well, it may have implications for thoracic endovascular aortic repair (TEVAR). Increased oversizing of the endograft, or additional computed tomography (CT) or IVUS imaging after fluid resuscitation for more adequate aortic measurements, may be needed in TTAI patients with considerable blood loss.
Jonker
F H W
FH
Section of Vascular Surgery and Interventional Radiology, Yale University School of Medicine, New Haven, CT 06510, USA.
Mojibian
H
H
Schlösser
F J V
FJ
Botta
D M
DM
Indes
J E
JE
Moll
F L
FL
Muhs
B E
BE
D000818:Animals; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging* / Q000293:injuries / Q000503:physiopathology* / Q000601:surgery; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation; D004195:Disease Models, Animal; D005440:Fluid Therapy; D008297:Male; D012771:Shock, Hemorrhagic / Q000503:physiopathology* / Q000628:therapy; D013552:Swine; D018084:Ultrasonography, Interventional