Point-of-care ultrasound (POCUS) practices in the helicopter emergency medical services in Europe: results of an online survey oleh Peter Hilbert-Carius, Manuel F. Struck, Marcus Rudolph, Jürgen Knapp, Leif Rognås, Jörn Adler, Cor Slagt, Lars Jacobsen, Henryk Pich, Michael D. Christian, Didier Dandrifosse, Fikri M. Abu-Zidan, POCUS in HEMS collaborators