The effect of deferoxamine on tolerance to secondary ischaemia caused by venous obstruction.

The current study investigated the efficacy of deferoxamine for treating secondary ischaemia due to venous obstruction in a rodent epigastric pedicle flap model. Rats receiving one dose of the free radical scavenger and iron chelator deferoxamine (150 mg/kg) intravenously prior to reperfusion had a mild improvement in flap survival: 46% in controls, 77% in deferoxamine-treated. This was statistically significant at p less than 0.05 (chi 2 = 5.2). This suggests that free radicals are partly involved in the mechanism of ischaemia/reperfusion injury in secondary ischaemia, as has been previously demonstrated for primary ischaemia (Angel et al., 1986b). Supporting biochemical evidence will be necessary to understand better the mechanisms involved in secondary ischaemia.