Systems and methods for instillation purging

A method of treating a tissue site with negative-pressure and therapeutic solution, the method comprising:

• delivering the negative pressure to the tissue site for a first interval;
• delivering a fill volume of the therapeutic solution to the tissue site for a second interval;
• and
• delivering a purge volume of the therapeutic solution to the tissue site.

An apparatus for treating a tissue site, the apparatus comprising:

• a supply of negative pressure;
• a solution source;
• and
• a controller operatively coupled to the supply of negative pressure and to the solution source, the controller configured to:
• deliver negative pressure to the tissue site for a negative-pressure interval;
• deliver a fill volume of instillation fluid to the tissue site for an instillation interval;
• and
• deliver a purge volume of instillation fluid to the tissue site at a purge frequency in response to completion of the instillation interval.