“…(2) Preoperative data: prehospital diet and exercise (irregular diet habits, probiotics intake, roughage intake, vegetable intake, make exercise, barthel score), past history (constipation, hemorrhoids, hypertension, diabetes Mellitus, hyperthyroidism, hypothyroidism, stroke, cancer, anemia, hypoproteinemia), drug use (polypharmacy (the types of long-term drug use were ≥5), antidepressant, antihypertensive), New York Heart Association (NYHA) stage, stool routine (latent occult blood test, stool characteristics, color of stool), preoperative constipation, laxatives were used before surgery, gastric tube was used before surgery, restricted to bed before surgery, sleep duration during hospitalization ≥7 h. (3) Related to cardiovascular surgery: preoperative ultrasound (heart rate, ejection fractions (EF) value), surgical classification, surgical incision location, operation time, duration of anesthesia, cardiopulmonary bypass, intraoperative blood loss, intraoperative blood transfusion. (4) Postoperative data: fever in intensive care unit (ICU), ventilator usage time, preoperative ultrasound (EF value), drainage volume within 24 hours after surgery, total volume in postoperative day, postoperative water intake, medication use during hospitalization (hypnotics, cough medicine, sedative, painkillers), reduced food intake, psychological or behavioral barriers to defecation in the hospital environment (contains either item: decreased appetite, decreased mobility, stress, hospital environment, and embarrassment) [14].…”