Temporary shunt system with a heparin-coated inner surface for interruption of cerebral circulation: Experiments in primates

OBJECTIVE: Temporary interruption of the cerebral circulation is sometimes required during the course of neurosurgical procedures. It would be beneficial to develop some type of vascular shunt system that could be used when temporary interruption of the cerebral circulation is necessary. Recent advances in the production of hemocompatible materials suggested to us that it would be possible to develop a small caliber temporary shunt system. METHODS: We developed and investigated in primates a small caliber, temporary arterial shunt system. The heparin-coated shunt catheter was 30 cm in length and had an internal diameter of 1.2 mm. Five Japanese monkeys were used for these experiments. Flow was maintained for 3 hours through a shunt connecting the radial and carotid arteries. We investigated the following: 1) biocompatibility of the catheter, 2) patency of the system, 3) flow through the system, 4) histology of the inner surface of the catheter, 5) biochemical analysis of blood components adhering to the inner surface of the catheter, and 6) histology of perfused brain. RESULTS: Angiography performed through the shunt showed adequate distal cerebral perfusion. Flow through the catheters was 47 +/- 1.7 ml per minute. Analysis of the shunt catheter at the conclusion of the perfusion period showed no clot formation in the lumen by gross inspection or electron microscopy. CONCLUSION: This system could prove useful for preventing cerebral ischemia during the course of neurosurgical procedures in which the cerebral circulation must be temporarily interrupted.