Eight pre - and postoperative factors , including earlier MI ( OR = 2.03 ) , American Society of Anesthesiologists class 3 ( OR = 1.34 ) , dementia ( OR = 6.22 ) , hemorrhage ( OR = 1.81 ) , delayed gastric emptying ( OR = 1.78 ) , surgical site infection ( OR = 3.31 ) , sepsis ( OR = 3.10 ) , and short length of stay ( OR = 1.51 ) were independently predictive of readmission .