Before sitting down for turkey dinner, Bloodworks Northwest is urging everyone to roll up their sleeves and donate blood. Bloodworks Northwest issued a plea for donations this week as the organization braces for the holiday season downturn, when the number of donors drops by 15 to 20 percent. Blood donor centers across the state will operate extended hours to make donating more convenient. The Bloodworks Northwest Vancouver Donor Center, 9320 N.E.