Table 3.
Effect of perioperative variables on PPC
| PPC No. (%) | Yes (%) | ||
|---|---|---|---|
| n | 236 | 32 | |
| Age (years, IQR) | 67 (53–76) | 60 (57–67) | 0.404 |
| Gender | 0.647 | ||
| Male | 145 (61.4) | 21 (65.6) | |
| Female | 91 (38.6) | 11 (34.4) | |
| Body mass index (kilograms/metres2, IQR) | 27.3 (23.8–30.5) | 27.1 (25.6–29.9) | 0.742 |
| American Society of Anesthesiologists physical status classification system | 0.244 | ||
| 1 | 50 (21.2) | 3 (9.4) | |
| 2 | 119 (50.4) | 13 (40.6) | |
| 3 | 58 (24.7) | 12 (37.6) | |
| 4 | 6 (2.5) | 2 (6.2) | |
| Unknown | 3 (1.2) | 2 (6.2) | |
| Current smoker | 36 (15.3) | 6 (18.8) | 0.662 |
| Chronic obstructive pulmonary disease | 22 (9.3) | 8 (25.0) | 0.009 |
| Previous cerebrovascular accident | 21 (8.9) | 2 (6.3) | 0.603 |
| Urea (milligrams per decilitre, IQR) | 5.6 (4.5–7.3) | 5.4 (4.0–9.4) | 0.886 |
| Proton pump inhibitor | 80 (33.9) | 9 (28.1) | 0.515 |
| Steroids | 13 (5.5) | 3 (9.4) | 0.390 |
| Cancer operation | 67 (28.4) | 15 (46.9) | 0.035 |
| Type of operation | 0.270 | ||
| Gastric | 24 (10.2) | 4 (12.5) | |
| Hepatobiliary/pancreatic | 17 (7.2) | 2 (6.3) | |
| Small bowel | 12 (5.1) | 1 (3.1) | |
| Colorectal | 66 (28.0) | 10 (31.3) | |
| Urological | 55 (23.3) | 2 (6.3) | |
| Vascular | 52 (22.0) | 10 (31.3) | |
| Other | 10 (4.2) | 3 (9.2) | |
| Perioperative antibiotics | 200 (84.7) | 26 (81.3) | 0.860 |
| Type of intubation | 0.946 | ||
| Laryngeal mask airway | 54 (22.9) | 6 (18.8) | |
| Cuffed/uncuffed endotracheal tube | 181 (76.7) | 26 (81.2) | |
| Unknown | 1 (0.4) | 0 (0.0) | |
| Method of operation | 0.722 | ||
| Laparoscopic | 72 (30.5) | 5 (15.6) | |
| Laparoscopic-assisted | 5 (2.1) | 1 (3.1) | |
| Laparoscopic converted to open | 6 (2.5) | 2 (6.3) | |
| Open | 145 (61.4) | 24 (75.0) | |
| Endovascular | 8 (3.5) | 0 (0.0) | |
| Bowel resection | 61 (25.8) | 13 (17.6) | 0.079 |
| Nasogastric tube | 6 (2.5) | 3 (9.4) | 0.011 |
| Duration of surgery (minutes, IQR) | 100 (55–170) | 212 (182–294) | <0.001 |
| Elective critical care admission | 33 (14.0) | 19 (59.4) | <0.001 |
| Analgesia use in the first 24 h | <0.001 | ||
| Epidural | 26 (11.0) | 14 (43.8) | |
| Patient controlled analgesia | 40 (16.9) | 10 (31.3) | |
| Wound catheter | 2 (0.1) | 0 (0.0) | |
| Oral analgesia only | 166 (70.3) | 7 (21.8) | |
| Unknown | 2 (0.1) | 1 (3.1) | |
| Change in analgesia strategy in the first 24 h | 148 (62.7) | 23 (71.9) | 0.014 |
| Incentive spirometer | 1 (0.4) | 2 (6.3) | <0.001 |