US Patent 7022113 Control of vacuum level rate of change

A wound treatment apparatus has a vacuum bandage covering a wound of a patient, a vacuum source coupled to the vacuum bandage, and a controller that operates the vacuum source to apply negative pressure to the wound through the bandage in a controlled manner. The controller is programmed to limit the rate of change of the negative pressure applied to the wound. A caregiver has the ability to change one or more negative pressure setpoint values and the controller of the wound treatment apparatus controls the rate of change of the negative pressure to reduce patient discomfort.