The difficulty in identifying an intestine deprived of arterial blood supply is well known to those who do abdominal surgery. As Orr et al1 so aptly stated in 1954, "We now doubt our ability to draw a sharp line between viable and non-viable intestine upon its appearance, unless frank necrosis with slough has developed." In addition to the problems of arterial catastrophes, the question of viability of intestine may arise in the performing of a colostomy, an ileostomy, and in the preparation of intestine for various substitution procedures.
Birnbaum and Ferrier2 found a 3% incidence of gangrene in the performance of colostomies. The application of an instrument which measures relative tissue impedance has recently proved of benefit in accurately detecting nonviable intestine.
The instrument employed in these studies was originally developed3 to assist in the accurate location of the bundle of His in cardiac surgery.* Employing