Table 5 The Cox proportional hazard model analysis of length of stay using raw cohort and matched cohort

Surgery

 LS

Reference

Reference

Reference

Reference

 OP

0.67(0.57,0.80)

 < .0001

0.74(0.61,0.90)

0.002

0.66(0.51,0.85)

0.001

0.58(0.45,0.75)

 < .0001

 Female

1.08(0.91,1.27)

0.378

0.83(0.64,1.07)

0.147

 Age ≥ 60y

1.11(0.94,1.32)

0.228

1.10(0.85,1.43)

0.465

BMI

 18.5

Reference

Reference

 18.5 ~ 24

1.39(0.93,2.06)

0.108

0.84(0.44,1.59)

0.584

 > 24

1.07(0.89,1.29)

0.480

1.14(0.86,1.52)

0.360

ASA

 I

Reference

Reference

 II

0.91(0.74,1.11)

0.347

0.91(0.68,1.20)

0.494

 III

0.81(0.62,1.06)

0.131

0.73(0.49,1.09)

0.120

CA199, U/ml

  ≤ 50

Reference

Reference

Reference

Reference

 50 ~ 400

0.57(0.46,0.72)

 < .0001

0.60(0.47,0.76)

 < .0001

0.67(0.48,0.95)

0.025

0.455(0.315,0.658)

 < .0001

  ≥ 400

0.64(0.50,0.81)

0.001

0.59(0.450,0.77)

 < .0001

0.75(0.50,1.11)

0.144

0.424(0.279,0.645)

 < .0001

 Tumor size > 3 cm

1.12(0.94,1.33)

0.214

1.01(0.76,1.33)

0.963

 Lymphnodes > 8

0.91(0.75,1.09)

0.292

1.03(0.78,1.36)

0.855

 Preoperative Tbil > 85.5 μmol/L

0.85(0.73,1.01)

0.057

0.77(0.58,1.02)

0.064

 Preoperative AST > 40 μmol/L

0.69(0.58,0.83)

 < .0001

0.83(0.62,1.11)

0.208

 Preoperative ALT > 40 μmol/L

0.59(0.48,0.71)

 < .0001

0.74(0.59,0.91)

0.005

0.62(0.46,0.84)

0.002

CA199, U/ml

  ≤ 50

Reference

Reference

Reference

Reference

 50 ~ 400

0.57(0.46,0.72)

 < .0001

0.60(0.47,0.76)

 < .0001

0.67(0.48,0.95)

0.025

0.46(0.32,0.66)

 < .0001

  ≥ 400

0.64(0.50,0.81)

 < .0001

0.59(0.45,0.77)

 < .0001

0.75(0.50,1.11)

0.144

0.42(0.28,0.65)

 < .0001

Operating time, min

 ≤ 200

Reference

Reference

 200 ~ 400

1.13(0.84,1.51)

0.428

1.23(0.79,1.91)

0.353

  ≥ 400

0.94(0.68,1.29)

0.683

1.20(0.75,1.93)

0.446

IBL, ml

  ≤ 100

Reference

Reference

 100 ~ 500

0.75(0.62,0.92)

0.004

0.95(0.77,1.17)

0.625

0.90(0.66,1.23)

0.523

  ≥ 500

0.49(0.39,0.61)

 < .0001

0.54(0.42,0.69)

 < .0001

0.66(0.47,0.91)

0.013

Transfusion during surgery

Hepatectomy

 Bile duct only

Reference

Reference

 Left hemihepatectomy

1.16(0.97,1.39)

0.100

1.26(1.02,1.55)

0.029

1.02(0.77,1.35)

0.909

 Right hemihepatectomy

0.57(0.43,0.75)

 < .0001

0.78(0.57,1.05)

0.104

0.72(0.49,1.07)

0.102

 Left Segmentectomy

0.73(0.32,1.64)

0.444

1.06(0.45,2.47)

0.895

0.81(0.25,2.55)

0.712

 Right Segmentectomy

0.73(0.34,1.54)

0.403

0.88(0.38,2.02)

0.761

0.64(0.26,1.58)

0.336

 Bile duct and part of hepatectomy

0.67(0.41,1.08)

0.098

0.78(0.45,1.37)

0.390

0.86(0.47,1.56)

0.618

 Conversion to laparotomy

0.80(0.50,1.28)

0.351

0.79(0.43,1.44)

0.440

Vascular resection

 None

Reference

Reference

 Hepatic artery

0.74(0.52,1.06)

0.101

0.79(0.48,1.29)

0.342

 Portal vein

0.71(0.46,1.10)

0.127

0.54(0.24,1.22)

0.138

 Hepatic artery & Portal vein

0.44(0.32,0.61)

 < .0001

0.49(0.29,0.81)

0.006

 Vascular reconstruction

0.74(0.50,1.11)

0.141

0.58(0.30,1.12)

0.105

Digestive reconstruction

 Choledochojejunostomy

Reference

Reference

 Hepaticojejunostomy

0.69(0.58,0.82)

 < .0001

0.808(0.662,0.986)

0.035

0.75(0.58,0.98)

0.034

 Biliary plasty

0.93(0.79,1.10)

0.377

1.02(0.80,1.308)

0.868

TNM

 I(T1N0M0)

Reference

Reference

Reference

 II(T2a/2bN0M0)

0.94(0.73,1.21)

0.636

1.04(0.80,1.36)

0.777

0.97(0.67,1.39)

0.851

 IIIA(T3N0M0)

0.82(0.59,1.14)

0.238

0.95(0.66,1.36)

0.761

0.88(0.511,1.53)

0.655

 IIIB(T4N0M0)

1.43(1.01,2.03)

0.047

2.40(1.62,3.55)

 < .0001

1.29(0.72,2.31)

0.388

 IVA(T, N2M0)

0.80(0.60,1.06)

0.119

1.13(0.83,1.54)

0.444

0.82(0.53,1.24)

0.343

 IVB(T,N,M1)

0.95(0.65,1.38)

0.788

1.09(0.74,1.62)

0.665

0.83(0.47,1.48)

0.534

 Abdominal abscess

0.44(0.33,0.59)

 < .0001

0.46(0.34,0.62)

 < .0001

0.47(0.31,0.70)

0.0002

0.41(0.27,0.63)

 < .0001

 Hemorrhage

0.44(0.29,0.67)

 < .0001

0.39(0.26,0.61)

 < .0001

0.50(0.28,0.92)

0.027

0.33(0.18,0.63)

0.0007

 Biliary fistula

0.49(0.35,0.68)

 < .0001

0.50(0.36,0.71)

 < .0001

0.64(0.39,1.04)

0.074

0.54(0.33,0.89)

0.016

 Heart failure

0.46(0.25,0.86)

0.016

0.26(0.13,0.51)

 < .0001

0.39(0.14,1.05)

0.061

0.18(0.07,0.50)

0.001

 Incision infection

0.31(0.17,0.54)

 < .0001

0.37(0.21,0.66)

0.001

0.39(0.19,0.80)

0.009

 Pneumonia

0.49(0.35,0.69)

 < .0001

0.49(0.34,0.71)

 < .0001

0.67(0.41,1.09)

0.105

 ARDS

0.36(0.17,0.75)

0.007

0.45(0.17,1.20)

0.109

 Liver failure

0.37(0.18,0.79)

0.010

0.38(0.12,1.17)

0.092

 Reoperation

0.25(0.10,0.61)

0.002

0.21(0.07,0.65)

0.007

0.308(0.10,0.98)

0.046

 Renal failure

0.28(0.12,0.69)

0.005

0.29(0.09,0.90)

0.032