A patient has mild skin, abdominal pain, fever, and a rigid abdomen. Labs showed leukocytosis, a blood sugar of 55 mg/dL, a sodium value of 119 mEq/dL, and a potassium value of 6.2 mEq/dL. Her blood pressure is 88/58 mm Hg. She undergoes an exploratory laparotomy. Which of the following is the definitive treatment for her primary condition?