Table 1 Demographic, surgical and anaesthetic variables, and unadjusted analysis of risk factors associated with 30-day readmission
Preoperative Risk Factors | Not Readmitted (n = 2495) | Readmitted Within 30 Days (n = 249) | p-value |
|---|---|---|---|
Age (years)* | 63.3 ± 10.9 | 65.8 ± 11.0 |  < 0.001 |
Gender | Â | Â | 0.55 |
 Female | 1142 (45.8) | 109 (43.8) |  |
 Male | 1353 (54.2) | 140 (56.2) |  |
Ethnicity | Â | Â | 0.29 |
 Chinese | 1749 (70.1) | 160 (64.3) |  |
 Malay | 483 (19.4) | 58 (23.3) |  |
 Indian | 207 (8.3) | 25 (10.0) |  |
 Others | 56 (2.2) | 6 (2.4) |  |
ASA Classification* |  |  |  < 0.001 |
 ASA 1—2 | 1326 (54.7) | 79 (32.9) |  |
 ASA 3—5 | 1099 (645.3) | 161 (67.1) |  |
Surgery Status | Â | Â | 0.23 |
 Elective | 1765 (71.0) | 175 (70.3) |  |
 Emergency | 722 (29.0) | 74 (29.7) |  |
Surgical Discipline* | Â | Â | 0.01 |
 General Surgery, Urology, O&G | 993 (39.8) | 109 (43.8) |  |
 Orthopaedics | 874 (35.0) | 70 (28.1) |  |
 Neurosurgery | 161 (6.5) | 18 (7.2) |  |
 Ophthalmology & Otolaryngology | 227 (9.1) | 14 (5.6) |  |
 Thoracic and Vascular | 181 (7.3) | 29 (11.6) |  |
 Others | 59 (2.4) | 9 (3.6) |  |
Type of Anaesthesia | Â | Â | 0.12 |
 General Anaesthesia | 1983 (85.4) | 203 (81.5) |  |
 General Anesthesia with CNB | 23 (1.0) | 6 (2.4) |  |
 Regional Anaesthesia | 213 (9.2) | 25 (10.0) |  |
 Monitored Anaesthesia Care | 102 (4.4) | 15 (6.0) |  |
Duration of Surgery | Â | Â | 0.13 |
 Less than 2 h | 899 (52.4) | 116 (58) |  |
 More than 2 h | 818 (47.6) | 84 (42) |  |
Obesity (BMI > 27.5)* | 395 (15.8) | 59 (23.7) |  < 0.001 |
Smoker | 259 (10.4) | 25 (10.1) | 0.88 |
Asthma* | 134 (5.4) | 25 (10.0) |  < 0.001 |
Hypertension* | 1454 (58.3) | 165 (66.3) | 0.02 |
Hyperlipidaemia* | 1209 (48.5) | 144 (57.8) | 0.01 |
Diabetes Mellitus* | 703 (28.2) | 98 (39.4) |  < 0.001 |
Renal Disease* | 281 (11.3) | 69 (27.7) |  < 0.001 |
Malignancy* | 375 (15.0) | 57 (22.9) |  < 0.001 |
Congestive Cardiac Failure | 59 (2.4) | 9 (3.6) | 0.23 |
Ischaemic Heart Disease* | 437 (17.5) | 67 (26.9) |  < 0.001 |
Valvular Heart Disease | 100 (4.0) | 13 (5.2) | 0.36 |
Peripheral Vascular Disease* | 85 (3.4) | 21 (8.4) |  < 0.001 |
Arrhythmias* | 150 (6.0) | 33 (13.3) |  < 0.001 |
Acute Myocardial Infarction (Within 1 Month) | 21 (0.8) | 4 (1.6) | 0.28 |
Chronic Obstructive Pulmonary Disease* | 37 (1.5) | 11 (4.4) |  < 0.001 |
Obstructive Sleep Apnoea | 88 (3.5) | 12 (4.8) | 0.37 |
Seizures | 31 (1.2) | 6 (2.4) | 0.14 |
Liver Disease | 74 (3.0) | 11 (4.4) | 0.21 |
Hematology | 92 (3.7) | 10 (4.0) | 0.79 |
Cerebrovascular Disease* | 242 (9.7) | 47 (18.9) |  < 0.001 |
Other CNS Comorbidities* | 121 (4.8) | 19 (7.6) | 0.06 |
Thyroid Disease | 160 (6.4) | 18 (7.2) | 0.62 |
Anaemia*a | 1035 (42.9) | 151 (60.9) |  < 0.001 |