Kazuo Neya

Reduction of Reperfusion Injury by Recombinant Human Superoxide Dismutase Administered Intravenously Just prior to Reperfusion

The reduction of reperfusion injury by intravenous administration of recombinant human superoxide dismutase (r-hSOD) was evaluated in a dog model. Two hours of left anterior coronary artery clamping were followed by 30 min of partial reperfusion and 30 min of full reperfusion. In the SOD group, r-hSOD (100,000 U/kg) was given intravenously 5 min before reperfusion. Measured left ventricular (LV) segments were classified thermographically by temperature drop into central (> or = 2 degrees C) and marginal (< 2 degrees C) areas. The regional LV functions were evaluated by percentages of both segmental (%SS) and active (%AS) shortening. In the central area, the %SS values after reperfusion were -9% in the control group and -3% in the SOD group (p < 0.05). The respective %AS values were 6 and 29% (p < 0.01). In the marginal area, both groups had %SS values of -3% and respective %AS values of 34 and 22% (all not significant) after reperfusion. In the central area, there was significantly better LV function recovery in the SOD group than in the control group.

Continuous Selective Cold Perfusion in Thoracoabdominal Aneurysm Repair

Fifteen patients with a mean age of 57 ± 17 years underwent thoracoabdominal aortic aneurysm repair under continuous selective blood perfusion of the intercostal and visceral arteries. Three aneurysms were Crawford type I, 6 were type II, and 6 were type III. Surgery was performed on an emergency basis in 5 cases. All operations were carried out using distal perfusion with mild hypothermia (> 32°C) in 13 cases and deep hypothermia (< 20°C) in 2 cases when a proximal clamp was undesirable. During aortic replacement, the intercostal arteries between the eighth thoracic and first lumbar vertebrae and the visceral arteries were reconstructed separately with a prosthetic graft under selective cold blood perfusion (22°C to 26°C). Flow was maintained above 100 mL·min−1. The durations of operation, selective intercostal and visceral perfusion, and distal perfusion were 9 ± 2 hours, 70 ± 35 minutes, and 170 ± 80 minutes, respectively. There was one operative death (mortality, 6.7%) due to respiratory failure and one case of delayed paraparesis. There was no paraplegia, acute hepatorenal failure, or bowel ischemia postoperatively. This experience suggests that continuous selective cold blood spinal and visceral perfusion during thoracoabdominal aneurysm repair can provide adequate organ protection.