Superoxide dismutase and catalase in skin flaps during venous occlusion and reperfusion.

We studied the enzymatic concentrations of superoxide dismutase (SOD) and catalase (CAT) in rabbit abdominal island skin flaps during 8 and 10 hours of venous occlusion followed by 4 hours of reperfusion. A correlation between such enzyme activity at the end of ischemia and flap viability was tested. The results show that the accumulation of blood and blood-derived substances cause enzyme activity to increase considerably during venous occlusion. The amount of increase was similar for both 8- and 10-hour venous occlusion. "True tissue enzyme activity" (corrected for the contribution of blood and blood-derived substances) remained constant during venous occlusion, suggesting that the availability of scavenging enzyme does not correlate with ultimate flap viability. During early reperfusion, however, both SOD and CAT activity decreased, suggesting that membrane damage leads to an increase in membrane permeability and to the loss of intracellular enzymes.

A survey of microsurgery training in the United States.

The increasing use of clinical and experimental microsurgical techniques has created a need for standardized, high-quality training programs in microsurgery. Toward this end, we conducted a study of the microsurgery instruction available in the United States. The data were collected from responses to surveys mailed to 55 microsurgery training centers across the country. Survey questions asked for a general characterization of each training program and its participants and for a specific description of course content. The results indicated that, even though training programs differed considerably, there were common elements. Total course length ranged from less than 40 hours to 80 hours, with a range of 32-40 hours devoted to basic microsurgery techniques. Forty percent of instructional programs were not certified for continuing medical education (CME) credit. Half of all reported trainees were residents in training. The basic microsurgery techniques common to most programs included instruction in microvascular end-to-end and end-to-side anastomoses of femoral arteries and veins in rats. Instruction in peripheral nerve repair was not offered. We conclude that, although there are merits to a diverse curriculum, it is time to institute a minimum level of standardized basic microsurgery training.