Our protocol for pulmonary hemorrhage includes intratracheal epinephrine, an extra dose of surfactant, and like you did HFOV.
In these cases, when there is active bleeding, we treat the PDA with paracetamol: 15 mg/k/dose every 6 hours for three to six days.
Good luck!
Patricia
Here's a link
J Pediatr. 2016 May 20. pii: S0022-3476(16)30176-7. doi: 10.1016/j.jpeds.2016.04.066. [Epub ahead of print]
Paracetamol Accelerates Closure of the Ductus Arteriosus after Premature Birth: A Randomized Trial.
Härkin P1, Härmä A1, Aikio O2, Valkama M1, Leskinen M1, Saarela T1, Hallman M1.