Thankfully this is the norm in many countries now. In emergencies UK doctors can obtain a ward of court order by telephone.
There is a kind of dance that everybody has to perform. The elders pretend they must resist blood. The parents tell the doctors they can't possibly give consent to blood. The doctors politely suggest it would be good to let the court take responsibility. The parents acquiesce. The court notes its respect for the sincere beliefs of all concerned and give temporary custody of the child to a ward of court who gives consent. The parents assure the court and the doctors of their respect for the decision of the court.
Outcomes - The child's life is saved. The parents are massively - and quietly relieved. The elders are even more quietly relieved. Job done.
Nobody actually believes that blood is more sacred than life.