Modification of the minimally invasive model for regional drug protection against spinal cord ischemia-reperfusion injury in rabbits

Objective To establish a minimally invasive model for regional aorta-infused drug protection against spinal cord ischemia-reperfusion injury in rabbits.Methods Spinal cord ischemia was induced in New Zealand rabbits by infrarenal abdominal aorta occlusion with different balloon catheters or an artery clamp for 30 min.During ischemia,normal saline or lidocaine 40 mg/kg was consecutively infused into the occluded aortic segments via a polycarbonate catheter through the femoral artery.Thereafter,blood flow was regained for reperfusion.Neurological function was assessed according to Tarlov scales postoperatively.L4-5 segements of the spinal cord were harvested at 48 h after reperfusion for histopathologic evaluation,and the total number of normal motor neurons in the anterior horn was counted.Results The 4F SwanGanz balloon catheter combined with a polycarbonate catheter was appropriate for modeling.Tarlov scores,the incidence of paraplegia (87.5％ in normal saline groups; 25.0％ vs.12.5％ in lidocaine groups) and the number of normal motor neurons [0 (0-1.75) vs.1 (0-2.00) in normal saline groups ; 8.5 (2.25-12.00) vs.9.0 (4.75-10.75) in lidocaine groups] were similar between balloon occlusion and aorta clamping while the same solution was infused (P ＞ 0.05).Conclusion The 4F Swan-Ganz balloon catheter combined with a polycarbonate catheter can be used to establish the minimally invasive model for regional drug protection against spinal cord ischemia-reperfusion instead of conventional aorta clamping in rabbits. Key words: Spinal cord ischemia;  Reperfusion injury ;  Aorta occlusion ;  Models,animal