Table 2 Univariate analysis of OS

^{ASA II}

^1.46

^1.00–2.13

^0.052

^{ASA III}

^2.35

^1.26–4.36

^0.007

^{Adjuvant treatment Yes}

^0.76

^0.59–0.97

^0.028

^{Blood transfusion Yes}

^1.09

^0.63–1.88

^0.755

^{Duration of anesthesia}

^1.01

^0.94–1.09

^0.717

^{Degree of differentiation}

^0.74

^0.55–0.98

^0.039

^Group

^0.87

^0.67–1.13

^0.307

^{Postoperative hospital stay}

^1.01

^1.00–1.02

^0.199

^{Pathological classification}

^{Squamous carcinoma}

^2.03

^0.58–7.13

^0.269

^{Surgical type McKeown}

^1.21

^0.92–1.59

^0.179

^{Surgical type Sweet}

^0.80

^1.26–0.58

^0.145

^{Surgical type Thoracoabdominal incision}

^1.04

^0.96–0.64

^0.865

^{TNM II}

^1.17

^0.80–1.70

^0.410

^{TNM III}

^1.57

^1.10–2.23

^0.013

^{Tumor location Middle esophagus}

^1.28

^0.98–1.66

^0.072

^{Tumor location Upper esophagus}

^1.54

^1.04–2.29

^0.031

^{Total hospital stay}

^1.01

^1.00–1.03

^0.044

^{The length of the operation}

^1.01

^0.94–1.10

^0.727