Comparison of baseline characteristics and perioperative variables between patients included in the analysis and those without an outpatient record on surgical pain assessment
| Variable | Included patients (n = 833) | Excluded patients (n = 739) | SMD |
|---|---|---|---|
| Propofol-based total intravenous anesthesia | 461 (55.3) | 207 (28.0) | 0.577 |
| Attending surgeon | 0.741 | ||
| Surgeon 1 | 531 (63.7) | 362 (49.0) | |
| Surgeon 2 | 138 (16.6) | 30 (4.1) | |
| Surgeon 3 | 88 (10.6) | 173 (23.4) | |
| Surgeon 4 | 55 (6.6) | 168 (22.7) | |
| Surgeon 5 | 21 (2.5) | 6 (0.8) | |
| Female | 448 (53.8) | 405 (54.8) | 0.021 |
| Age (yr) | 66.0 (60.0–73.0) | 65.0 (59.0–71.0) | 0.129 |
| Body mass index (kg/m2) | 24.1 (22.1–25.9) | 23.8 (21.9–25.9) | 0.010 |
| ASA physical status | 0.103 | ||
| I | 77 (9.2) | 50 (6.8) | |
| II | 671 (80.6) | 622 (84.2) | |
| III | 85 (10.2) | 67 (9.1) | |
| Smoking history | 130 (15.6) | 102 (13.8) | 0.051 |
| Extent of surgery | 0.229 | ||
| Wedge resection or metastatectomy | 81 (9.7) | 118 (16.0) | |
| Segmentectomy | 151 (18.1) | 151 (20.4) | |
| Lobectomy | 586 (70.3) | 465 (62.9) | |
| Others | 15 (1.8) | 5 (0.7) | |
| History of taking analgesics | |||
| Any analgesics | 73 (8.8) | 61 (8.3) | 0.018 |
| Opioids | 22 (2.6) | 16 (2.2) | 0.031 |
| History of taking neuropsychiatric drugs | |||
| Any medications | 60 (7.2) | 59 (8.0) | 0.029 |
| Antidepressants | 45 (5.4) | 39 (5.3) | 0.006 |
| Antianxiety drugs | 36 (4.3) | 44 (6.0) | 0.074 |
| History of thoracic operation | |||
| Any side | 54 (6.5) | 43 (5.8) | 0.028 |
| Ipsilateral side | 14 (1.7) | 13 (1.8) | 0.006 |
| Duration of anesthesia (hr) | 2.67 (2.33–3.08) | 2.33 (2.00–2.75) | 0.540 |
| Intraoperative opioids | |||
| Fentanyl | 318 (38.2) | 454 (61.4) | 0.478 |
| Remifentanil | 542 (65.1) | 306 (41.4) | 0.488 |
| Total amount of remifentanil equivalent dose (µg/kg/min) | 0.09 ± 0.06 | 0.06 ± 0.06 | 0.471 |
| Intraoperative regional analgesia | 708 (85.0) | 659 (89.2) | 0.125 |
| POD of chest tube removal | 3 (2–4) | 2 (1–4) | 0.244 |
| Removed at POD ≥ 4 | 320 (38.4) | 206 (27.9) | 0.225 |
| Maximum pain score at discharge day | 3 (2–3) | 3 (2–3) | 0.008 |
The values are presented as means ± standard deviations, medians (interquartile ranges), or numbers (%).
SMD: standardized mean difference, ASA: American Society of Anesthesiologists, POD: postoperative day.