Development of a Whole-Task Simulator for Carotid Endarterectomy.

Abstract

Surgical education relies on operative exposure with live patients. Carotid endarterectomy (CEA) demands an experienced surgeon with a very low complication rate. The high-risk nature of this procedure and the decline in number of CEAs performed annually has created a gap in residency training. To develop a high-fidelity whole-task simulation for CEA that demonstrates content, construct, and face validity. Anatomically accurate models of the human neck were created using multilayered poly-vinyl alcohol hydrogels. Graded polymerization of the hydrogel was achieved by inducing crosslinks during freeze/thaw cycles, stiffening the simulated tissues to achieve realistic tactile properties. Venous bleeding was simulated using pressure bags and a ventricular assistive device created pulsatile flow in the carotid. Ten surgeons performed the simulation under operating room conditions, and metrics were compared among experience levels to determine construct validity. Participants completed surveys about realism and usefulness to evaluate face validity. A significant difference was found in operative measures between attending and resident physicians. The mean operative time for the expert group was 63.6 min vs 138.8 for the resident group (P=.002). There was a difference in mean internal carotid artery clamp time of 43.4 vs 83.2 min (P=.04). There were only 2 hypoglossal nerve injuries, both in the resident group (P=.009). The whole-task CEA simulator is a realistic, inexpensive model that offers comprehensive training and allows residents to master skills prior to operating on live patients. Overall, the model demonstrated face and construct validity among neurosurgery and vascular surgeons.