Oxygenation of the cerebrospinal fluid with artificial cerebrospinal fluid can ameliorate a spinal cord ischemic injury in a rabbit model

Abstract

ObjectiveWe evaluated the effect of cerebrospinal fluid oxygenation for the prevention of spinal cord ischemic injury after infrarenal aortic occlusion in a rabbit model. MethodsTwenty white Japanese rabbits were categorized into the following 4 groups (5 in each): group S (sham), balloon catheter insertion on to the aorta; group C (control), spinal cord ischemic injury by infrarenal abdominal aortic balloon occlusion for 15 minutes; group N (nonoxygenated), spinal cord ischemic injury with cerebrospinal fluid replacement by nonoxygenated artificial cerebrospinal fluid; and group O (oxygenated), spinal cord ischemic injury with cerebrospinal fluid replacement by nanobubble-oxygenated artificial cerebrospinal fluid. The changes in cerebrospinal fluid partial pressure of oxygen during the peri-ischemic period, modified Tarlov score, and histopathology of the spinal cord 48 hours after aortic maneuvers were evaluated. ResultsCerebrospinal fluid partial pressure of oxygen significantly increased in group O compared with group N after cerebrospinal fluid replacement (254.5 ± 54.8 mm Hg vs 136.1 ± 43.5 mm Hg, P = .02). After 15 minutes of spinal cord ischemic injury, cerebrospinal fluid partial pressure of oxygen in group C decreased to 65.8 ± 18.6 mm Hg compared with baseline (148.8 ± 20.6 mm Hg, P < .01), whereas cerebrospinal fluid partial pressure of oxygen in group O was maintained at remarkably high levels after spinal cord ischemic injury (291.9 ± 51.8 mm Hg), which was associated with improved neurologic function, with 20% of spinal cord ischemic injury having a Tarlov score less than 5 compared with 100% of spinal cord ischemic injury in group C. Preservation of anterior horn neurons in groups N and O was confirmed by histopathologic analysis with significant reduction of degenerated neurons compared with group C. ConclusionsCerebrospinal fluid oxygenation with artificial cerebrospinal fluid can exert a protective effect against spinal cord ischemic injury in rabbits.