OBJECTIVE: This study was performed to determine the effect of delayed induction of mild hypothermia after transient spinal cord ischemia in rabbits. METHODS: Abdominal aortic occlusion was performed for 15 minutes to induce spinal cord ischemia at a rectal temperature of 37.3 +/- 0.3 degrees C. Four groups of rabbits were investigated: Group 1 (n = 8) was subjected to ischemia and reperfused at the same temperature for 7 hours; Group 2 (n = 8) was subjected to ischemia and reperfused at the same temperature for 1 hour, followed by 6 hours of systemic hypothermia (32.5 +/- 0.5 degrees C); Group 3 (n = 8) was subjected to ischemia, reperfusion at the same temperature for 3 hours and then 6 hours of systemic hypothermia (32.5 +/- 0.5 degrees C); and Group 4 (n = 8) comprised non-ischemic controls. Neurological status of all rabbits in Groups 1-3 was recorded and animals were sacrificed 1 week after ischemic injury. Spinal cord sections were examined microscopically to determine the extent of ischemic neuronal damage. RESULTS: Mean modified Tarlov's score at 1 week after ischemic insult was 0.5 +/- 0.8 in Group 1, compared to 43 +/- 1.5 in Group 2 and 2.9 +/- 1.8 in Group 3. Mean total number of surviving neurons within examined sections of spinal cord was significantly greater for Groups 2 and 3 compared with Group 1 (Group 1, 81 +/- 66.1; Group 2, 293.4 +/- 110.9; Group 3, 227.1 +/- 105.5; p < 0.001). CONCLUSIONS: Delayed postischemic hypothermia induced within 3 hours after reperfusion significantly reduces ischemia-induced spinal cord neuronal damage in rabbits.
OBJECTIVE: This study was performed to determine the effect of delayed induction of mild hypothermia after transient spinal cord ischemia in rabbits. METHODS: Abdominal aortic occlusion was performed for 15 minutes to induce spinal cord ischemia at a rectal temperature of 37.3 +/- 0.3 degrees C. Four groups of rabbits were investigated: Group 1 (n = 8) was subjected to ischemia and reperfused at the same temperature for 7 hours; Group 2 (n = 8) was subjected to ischemia and reperfused at the same temperature for 1 hour, followed by 6 hours of systemic hypothermia (32.5 +/- 0.5 degrees C); Group 3 (n = 8) was subjected to ischemia, reperfusion at the same temperature for 3 hours and then 6 hours of systemic hypothermia (32.5 +/- 0.5 degrees C); and Group 4 (n = 8) comprised non-ischemic controls. Neurological status of all rabbits in Groups 1-3 was recorded and animals were sacrificed 1 week after ischemic injury. Spinal cord sections were examined microscopically to determine the extent of ischemic neuronal damage. RESULTS: Mean modified Tarlov's score at 1 week after ischemic insult was 0.5 +/- 0.8 in Group 1, compared to 43 +/- 1.5 in Group 2 and 2.9 +/- 1.8 in Group 3. Mean total number of surviving neurons within examined sections of spinal cord was significantly greater for Groups 2 and 3 compared with Group 1 (Group 1, 81 +/- 66.1; Group 2, 293.4 +/- 110.9; Group 3, 227.1 +/- 105.5; p < 0.001). CONCLUSIONS: Delayed postischemic hypothermia induced within 3 hours after reperfusion significantly reduces ischemia-induced spinal cord neuronal damage in rabbits.
Authors: J Gonzalez-Fajardo; A Beatriz; J L Perez-Burkhardt; T Alvarez; L Fernandez; G Ramos; C Vaquero Journal: J Vasc Surg Date: 1996-03 Impact factor: 4.268