Continuous Intra-Arterial Catheter Access of Ischemic Cerebral Tissue (P5.229)

Objective: To establish and investigate continuous selective intra-arterial catheter access of ischemic brain. Background: Selective intra-arterial catheter access is now standard of care for select patients with large vessel occlusion strokes to achieve revascularization. To date, no group has evaluated the potential of maintaining continuous intra-arterial access to deliver neuroprotective agents directly into the ischemic territory. Methods: Sprague-Dawley rats (250-300gm) are anesthetized using ketamine/xylazine. Neck dissection is performed to visualize the common carotid (CCA) bifurcation. A guide catheter (polyethylene; ID: 280um, OD: 610um) is inserted into the rat ICA. A microcatheter (polyimide; ID: 140um, OD: 165um) is advanced 10mm beyond the bifurcation through the guide catheter. The guide catheter is then removed. The microcatheter is secured and attached to an infusion catheter which is exteriorized to the top of the head. To measure distal microvascular perfusion, a Laser Doppler Flowmetry (LDF) probe is glued on the skull in the center of the ipsilateral MCA field. Scanned images of 2,3,5-triphenyltetrazolium chloride (TTC) stained sections of rat forebrain are compared between left and normal right hemisphere to determine amount of cerebral edema and ischemic injury. Results: The procedure successfully establishes continuous selective intra-arterial catheter access in the rat ICA. The placement of the catheter is safe. The microcatheter does not change distal microvascular perfusion when compared to normal LDF values. During the procedure, there is 50[percnt] reduction in distal microvascular perfusion during microcatheter placement and return to normal after placement. At 6 and 12hrs post-catheterization, TTC staining reveals no significant cerebral injury. Conclusions: Continuous selective intra-arterial catheterization of the rat ICA using the described method is safe, does not compromise distal microvascular perfusion, and does not cause significant cerebral injury. Future studies will incorporate the procedure within a stroke model, establish continued patency, and deliver neuroprotective agents directly into the ischemic brain. Disclosure: Dr. Selvan has nothing to disclose. Dr. Barone has nothing to disclose.