Patent ID: 8620477

Claim:
A method of supporting a patient, the method comprising, with a pressure control assembly: monitoring the fluid pressure within at least one fluid containing bladder configured to support at least a portion of the weight of the patient; and regulating the fluid pressure within the at least one bladder by: defining an acceptable range of fluid pressures; adjusting the fluid pressure within the at least one bladder only when a fluid pressure value has been detected outside the acceptable range of fluid pressures and a time period following the detection of the fluid pressure value has elapsed without the fluid pressure within the at least one bladder returning to the acceptable range of fluid pressure values; defining the time period to have a length that is greater than zero and variable up to a maximum value, determining a difference between the fluid pressure value and the acceptable range of pressure values; dynamically determining the length of the time period based on the difference between the fluid pressure value and the acceptable range of pressure values, and determining the length of the time period differently based on the amount of the difference between the fluid pressure value and the acceptable range of pressure values.