Algorithm for determining and displaying compression and tissue gap in a circular stapler

A circular stapler apparatus comprising:

• an anvil;
• a stapling head arranged to cooperate with the anvil to compress tissue therebetween;
• an adjustment mechanism operable to move the anvil relative to the stapling head to compress the tissue;
• a sensor configured to provide an output indicative of a tissue compression value for the tissue compressed between the anvil and the stapling head;
• a display;
• and
• a controller in communication with the sensor and the display, the controller comprising at least one processor and memory storing instructions that, when executed by the at least one processor, cause the controller to:
• establish a range of expected compression values based on known tissue properties;
• determine, based on the output of the sensor, the tissue compression value;
• compare the tissue compression value to the range of expected compression values;
• and
• cause the display to present an indication that the tissue compression value is within the range of expected compression values.