The global emergency services database is a one-time download of about 220MB — do it on Wi-Fi before you leave.
Emergency facility data comes from OpenStreetMap, so coverage is richest in Europe and North America and thinner in some other regions; it improves as OpenStreetMap does.
This app locates facilities on an offline map. It does not provide turn-by-turn routing, real-time alerts, first-aid instruction, or a connection to emergency dispatch — always contact your local emergency number directly in an emergency.