Concurrent infusion with common line auto flush

A method for controlling operation of an infusion pump of an infusion pump system, the infusion pump system comprising a first reservoir configured to hold a first fluid, a second reservoir configured to hold a second fluid, a junction in fluid communication with the first reservoir and the second reservoir, a common line in fluid communication with the junction and having a terminal fluid delivery end, and the infusion pump, wherein the infusion pump is operable to drive fluid through the common line toward the terminal fluid delivery end, the method comprising:

• receiving instructions to deliver the first fluid at a first rate, subsequently concurrently deliver a mixture of the first fluid and the second fluid, and concurrently deliver the first fluid at the first rate and the second fluid at a second rate;
• infusing the first fluid at the first rate along a first flow path, the first flow path including the common line;
• determining a common line volume corresponding to a volume of the common line;
• drawing the first fluid from the first reservoir the second fluid from the second reservoir to deliver the mixture of the first fluid and the second fluid;
• infusing the mixture of the first fluid and the second fluid at a flushing rate along a second flow path, the second flow path including the common line;
• determining that an infused volume of the mixture of the first fluid and the second fluid equals or exceeds the common line volume;
• and
• changing the infusion rate of the mixture of the first fluid and the second fluid from the flushing rate to a combined rate, wherein the combined rate is the sum of the first rate and the second rate, and continue to infuse the mixture of the first fluid and the second fluid along the second flow path at the combined rate.