Systems and methods for delivering fluid to a wound therapy dressing

A system for delivering fluid to a wound therapy dressing, the system comprising:

• a pump comprising a vacuum port and a positive pressure port, the vacuum port adapted to be in fluid communication with the wound therapy dressing;
• an expandable member in fluid communication with the positive pressure port, wherein the expandable member is configured to exert a force on fluid within a fluid reservoir to expel fluid from the fluid reservoir, the fluid reservoir adapted to be in fluid communication with the wound therapy dressing;
• and
• a valve in fluid communication with the positive pressure port and the expandable member, wherein positive pressure from the positive pressure port is provided to the expandable member through the valve, and wherein the valve is configured to vent pressure to atmosphere.

A method of delivering fluid to a wound therapy dressing, the method comprising:

• operating a pressure source adapted to exert a positive pressure on fluid in a fluid reservoir and a negative pressure on the wound therapy dressing;
• monitoring the positive pressure on the fluid;
• providing a fluid control device adapted to supply the fluid from the fluid reservoir to the wound therapy dressing, the fluid control device comprising a control valve and a metering orifice, the metering orifice being sized to provide a fluid flow rate according to the positive pressure on the fluid;
• opening the control valve to provide a predetermined volume of the fluid from the fluid reservoir to the wound therapy dressing, the predetermined volume of the fluid corresponding to the fluid flow rate from the fluid reservoir for an elapsed time period;
• closing the control valve to restrict the fluid flow rate from the fluid reservoir to the wound therapy dressing after the elapsed time period;
• and
• maintaining negative pressure from the pressure source to the wound dressing.