Determination of intestinal viability

Operations for intestinal ischemia are frequently done by veterinarians. In equine surgery those conditions commonly producing ischemia are intussusception, volvulus, bowel obstructions, and incarcerated hernias. In an attempt to predict intraoperative bowel viability after the restoration of circulation, a variety of adjuvant methods have been investigated. There is little question that of the techniques currently available, sodium fluorescein injected intravenously approaches the ideal in predicting nonviability in humans and in most animal models. Furthermore, it is safe, takes little operating time, is inexpensive, and is ubiquitously available; in addition, the only special equipment needed is a long-wave ultraviolet lamp. Reliance on this method would seldom result in nonviable bowel being left in situ. Furthermore, the use of fluorescein would minimize the unnecessary resection of viable intestine and, thereby, minimize the postoperative nutritional problems that may occur, especially in equines. The report of Sullins et al questions the accuracy of the fluorescein technique in predicting viability and nonviability in horses and also raises the question as to whether the prediction of viability, after the restoration of intestinal blood flow, also predicts normal intestinal function. Further investigations will be needed to confirm or refute these observations.