A fluid-filled structure, such as a bladder, is disclosed. A pharmaceutically stable hemostatic liquid composition comprising a mixed solution of activated blood coagulation factor VII and blood coagulation factor X in a single container. 0\xd710\u22123 mol per 100 g of the gelatin. According to some embodiments, the pressure readings are provided to a microcontroller that uses a table and interpolation algorithms to calculate the flow of the air flowing through the venturi, such as the mass of air in a given unit of time. When the input rotational speed is too high, the dynamotor is operated in generator mode.