A reproducible canine model of nonocclusive mesenteric ischemia.

A technique for producing a reliable, clinically applicable, and highly reproducible canine model of nonocclusive mesenteric ischemia was developed. Following left thoracotomy in 10 dogs, a 1 mm diameter soft polyethylene tube was inserted into the pericardial space via a small puncture site. This tube was sealed in place with cyanoacrylate tissue adhesive. A solution of 10% Dextran 40 in saline was infused into the pericardial space until a 50% reduction (as monitored by electromagnetic flowmeter) in superior mesenteric artery flow (SMAQ) was obtained. Without additional intrapericardial infusion of the Dextran solution, SMAQ was reduced 51 +/- 4% to 54 +/- 3% of control values during a 60 minute post-tamponade observation period. During the same time. Cardiac output was depressed between 40 +/- 8% and 54 +/- 3%, and right atrial pressure remained elevated between 164 +/- 15% and 171 +/- 15%. Systemic arterial pressure initially dropped 28 +/- 5% but compensated to within 11 +/- 5% of pre-tamponade level at 60 minutes. The stability of this model is well suited for evaluating new experimental diagnostic and therapeutic procedures.