Blood transfusions at the scene save lives. But ambulances are rarely equipped to do them.

One August afternoon in 2023, Angela Martin's cousin called with alarming news. Martin's 74-year-old aunt had been mauled by four dogs while out for a walk near her home in rural Purlear, North Carolina. She was bleeding heavily from bites on both legs and her right arm, where she'd tried to protect her face and neck. An ambulance was on its way.

"Tell them she's on Eliquis!" said Martin, a nurse who lived an hour's drive away in Winston-Salem. She knew the blood thinner could lead to life-threatening blood loss.

When the ambulance arrived, the medics evaluated Martin's aunt and then did something few emergency medical services crews do: They gave her a blood transfusion to replace what she'd lost, stabilizing her sinking blood pressure.