Table 1 Comparison of patient characteristics data and prospensity score matching analysis between non-PONV and PONV group in observational cohort study

Female (n,%)

778 (31.2%)

444 (61.2%)

215.045

< 0.001

434 (62.0%)

418 (59.7%)

0.768

0.381

Age (year)

60.0 ± 11.1

59.1 ± 11.1

− 1.914

0.056

58.4 ± 12.0

58.9 ± 10.9

0.803

0.420

Age (year)

4.495

0.034

0.011

0.915

 ≦ 60

1144 (45.8%)

365 (50.3%)

355 (50.7%)

353 (50.4%)

 > 60

1353 (54.2%)

361 (49.7%)

345 (49.3%)

347 (49.6%)

BMI

23.5 ± 3.1

23.3 ± 3.2

−2.056

0.040

23.5 ± 3.2

23.3 ± 3.1

−1.348

0.178

ASA physical status

2.188

0.534

0.255

0.880

 I

172 (6.9%)

51 (7%)

56 (8.0%)

51 (7.3%)

 II

2063 (82.6%)

608 (83.8%)

581 (83.0%)

585 (83.6%)

 ≥ III

262 (10.5%)

67 (9.2%)

63 (9. 0%)

64 (9.1%)

Duration of anesthesia (h)

2.6 ± 1.0

2.3 ± 1.0

−5.243

< 0.001

2.3 ± 0.9

2.3 ± 1.0

0.551

0.582

Laparoscopic surgery

1730 (69.3%)

528 (72.7%)

3.181

0.075

504 (72.0%)

502 (71.7%)

0.014

0.905

Crystalloid solution (ml)

1305.3 ± 462.1

1238.7 ± 417.7

−3.491

< 0.001

1225.7 ± 436.5

1242.1 ± 418.5

0.718

0.420

Colloid solution (ml)

614.1 ± 318.0

572.2 ± 303.9

−3.309

0.001

562.1 ± 282.9

571.4 ± 307.2

0.590

0.555

Bood loss (ml)

147.7 ± 190.7

134.6 ± 173.7

−1.661

0.097

131.3 ± 168.2

134.9 ± 174.3

0.399

0.690

Intraoperative fentanyl usage (mg)

0.5 ± 0.2

0.5 ± 0.1

−3.965

< 0.001

0.5 ± 0.1

0.5 ± 0.1

0.628

0.530

Postoperative opioid (patient-controlled analgesia)

2360 (94.5%)

600 (82.6%)

105.726

<  0.001

610 (87.1%)

600 (85.7%)

0.609

0.435

Inhaled anesthesia

1633 (65.4%)

608 (83.7%)

89.381

<  0.001

569 (81.3%)

582 (83.1%)

0.826

0.364

Vagus nerve trunk resection

1046 (41.9%)

141 (19.4%)

122.052

< 0.001

246 (35.1%)

139 (19.9%)

41.017

< 0.001