What would be the minimally acceptable blood pressure for a 9-year-old girl who is suffering from a significant bleed from broken glass?

The normal blood pressure of children is 96/62 mmHg.
The blood pressure of an injured child decrease depending on its bleeding because the blood pressure depends on two things: Volume of the blood and the systolic ejection force. So when the volume of blood decreases the blood pressure decrease.
Thinks it as a pump with water at home, the less water there is then a less pressure is, and vice versa.
The minimally acceptable blood pressure for a 9-year-old child is 88mmHg (as a systolic pressure).

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