The Stanford Blood Center has put a call for blood donors, with its supplies running low. The center serves six area hospitals, including Stanford and Lucile Packard Children's hospitals.

The center is looking for all types of blood, especially type O, said Michelle Bussenius, the center's public relations director. When the center runs low on supplies, it has to import blood from elsewhere or tell local hospitals it can't fill their immediate orders, she said.

"It's always a problem during the summer," Bussenius said.

People may schedule appointments to donate blood by calling 1-888-723-7831, or through the center's Web site at bloodcenter.stanford.edu .

— Don Kazak