In a large bowl, lightly beat the egg whites and egg. Add 3/4 cup bread crumbs, chives, flour, pepper sauce, baking powder, salt and pepper; mix well. Fold in crab. Cover and refrigerate for at least 2 hours.
Place remaining bread crumbs in a shallow bowl. Drop crab mixture by scant 1/4 cupfuls into crumbs. Gently coat and shape into 1/2-in.-thick patties.
In a large nonstick skillet, cook crab cakes in oil in batches over medium-high heat for 3-4 minutes on each side or until golden brown. If desired, serve with lemon wedges.