Table 1.
Baseline patient and procedural characteristics of cases stratified by etomidate use. ∗Total fluid volume defined as the volumes of crystalloid plus one-and-a-half times colloid administered intraoperative exclusive of PRBCs. All comorbidities are within 1 yr of procedure date. All medications are prescriptions within 30 days of procedure except steroids (1 yr before). †Vasopressors in milligrams norepinephrine equivalents = total amount epinephrine + total amount norepinephrine + (total amount phenylephrine/10) + (total amount dopamine/weight [kg]/2). CAD, coronary artery disease; PVD, peripheral vascular disease; COPD, chronic obstructive pulmonary disease; CKD, chronic kidney disease; CCI, Charlson comorbidity index; ACE, angiotensin-converting enzyme; ARB, angiotensin receptor blocker; MAC, minimal alveolar concentration; PRBC, packed red blood cells; RVU, relative value unit of main procedure; sd, standard deviation; ENT, ear, nose, throat.
| Descriptor | Total (N=19 714) | No etomidate (N=16 893) | Etomidate (N=2821) | Standardised difference (%) |
|---|---|---|---|---|
| Patient characteristics | ||||
| Age (yr), mean (range) | 67.5 (18–107) | 66.7 (18–107) | 72.1 (18–104) | 40.0 |
| BMI (kg m−2), mean (sd) | 29.5 (7.8) | 29.7 (7.9) | 28.4 (7.0) | –17.4 |
| Female sex, no. (%) | 8745 (44.4) | 7591 (44.9) | 1154 (40.9) | –8.1 |
| ASA physical status, median (IQR) | 3 (3, 3) | 3 (3, 3) | 3 (3, 4) | 63.7 |
| Hypertension, no. (%) | 14 792 (75.0) | 12 734 (75.4) | 2058 (73.0) | –5.5 |
| Hyperlipidaemia, no. (%) | 11 863 (60.2) | 10 141 (60.0) | 1722 (61.0) | 2.1 |
| Diabetes mellitus, no. (%) | 8182 (41.5) | 6830 (40.4) | 1352 (47.9) | 15.2 |
| On insulin, no. (%) | 4472 (22.7) | 3938 (23.3) | 534 (18.9) | –10.8 |
| CAD, no. (%) | 10 282 (52.2) | 8383 (49.6) | 1899 (67.3) | 36.5 |
| Atrial fibrillation, no. (%) | 7789 (39.5) | 6480 (38.4) | 1309 (46.4) | 16.2 |
| PVD, no. (%) | 3751 (19.0) | 2950 (17.5) | 801 (28.4) | 26.1 |
| Ischaemic stroke, no. (%) | 1446 (7.3) | 1262 (7.5) | 184 (6.5) | –3.9 |
| COPD, no. (%) | 4636 (23.5) | 3881 (23.0) | 755 (26.8) | 8.8 |
| CKD, no. (%) | 6723 (34.1) | 5570 (33.0) | 1153 (40.9) | 16.4 |
| CCI, median (IQR) | 5 (3, 7) | 5 (3, 7) | 5 (3, 7) | 6.0 |
| Smoking, no. (%) | 4589 (23.3) | 4107 (24.3) | 482 (17.1) | –17.8 |
| Beta blocker, no. (%) | 8193 (41.6) | 7318 (43.3) | 875 (31.0) | –25.7 |
| ACE inhibitor/ARB, no. (%) | 7357 (37.3) | 6303 (37.3) | 1054 (37.4) | 0.2 |
| Hydralazine/nitrates, no. (%) | 2698 (13.7) | 2316 (13.7) | 382 (13.5) | –0.6 |
| Aldosterone antagonists, no. (%) | 1587 (8.1) | 1308 (7.7) | 279 (9.9) | 7.8 |
| Digoxin, no. (%) | 1498 (7.6) | 1212 (7.2) | 286 (10.1) | 10.3 |
| Steroid use, no. (%) | 3402 (17.3) | 3159 (18.7) | 243 (8.6) | –29.7 |
| Antiplatelet use, no. (%) | 8611 (43.7) | 7485 (44.3) | 1126 (39.9) | –8.9 |
| Anticoagulant use, no. (%) | 4802 (24.4) | 4149 (24.6) | 653 (23.2) | –3.3 |
| Ejection fraction (EF), mean (sd) no. (%) | 55.6 (15.0) | 57.2 (14.0) | 46.2 (17.5) | –69.4 |
| EF >40% | 7542 (38.3) | 6777 (40.1) | 765 (27.1) | –27.8 |
| EF 20–40% | 1602 (8.1) | 1112 (6.6) | 490 (17.4) | 33.7 |
| EF <20% | 117 (0.6) | 51 (0.3) | 66 (2.3) | 17.7 |
| Missing | 10 453 (53.0) | 8.953 (53.0) | 1500 (53.2) | 0.4 |
| Procedural characteristics | ||||
| Intraoperative etomidate use, no. (%) | 2821 (14.3) | – | – | – |
| Intraoperative agent use, no. (%) | ||||
| Etomidate only | 1244 (6.3) | 0 | 1244 (44.1) | 125.6 |
| Propofol only | 15 539 (78.8) | 15 539 (95.2) | 0 | –629.8 |
| Ketamine only | 30 (0.2) | 30 (5.3) | 0 | –33.5 |
| Etomidate and propofol | 1508 (7.6) | 0 | 1508 (53.5) | 151.7 |
| Etomidate and ketamine | 27 (0.1) | 0 | 27 (1.0) | 4.5 |
| Propofol and ketamine | 791 (4.0) | 791 (4.7) | 0 | –31.4 |
| All three | 42 (0.2) | 0 | 42 (1.5) | 17.5 |
| No agent | 533 (2.7) | 533 (3.2) | 0 | –25.7 |
| Propofol (total) | 17 880 (90.7) | 16 330 (96.7) | 1550 (55.0) | –111.6 |
| Ketamine (total) | 890 (4.5) | 821 (4.9) | 69 (2.5) | –12.7 |
| Emergency status, no. (%) | 1664 (8.4) | 1253 (7.4) | 411 (14.6) | 23.2 |
| Admission type, no. (%) | ||||
| Ambulatory | 2812 (14.3) | 2623 (15.5) | 189 (6.7) | –28.3 |
| Same-day admit | 8860 (44.9) | 7668 (45.4) | 1192 (42.3) | –6.3 |
| Inpatient | 8042 (40.8) | 6602 (39.1) | 1440 (51.1) | 24.3 |
| Neuraxial anaesthesia, no. (%) | 793 (4.0) | 737 (4.4) | 56 (2.0) | –13.7 |
| Age adjusted MAC, mean (sd) | 0.84 (0.35) | 0.83 (0.35) | 0.85 (0.34) | 5.8 |
| Total fluid volume (ml),∗ median (IQR) | 1703 (900, 3000) | 1500 (825, 2750) | 2250 (1250, 3750) | 29.1 |
| Estimated blood loss (ml), median (IQR) | 0 (0, 50) | 0 (0, 100) | 0 (0, 0) | –17.5 |
| Urine output (ml), median (IQR) | 0 (0, 200) | 0 (0, 200) | 0 (0, 0) | –23.7 |
| PRBC (units), mean (sd) | 0.18 (0.81) | 0.16 (0.77) | 0.31 (1.02) | 16.6 |
| Total vasopressors, mg norepinephrine equivalents,† median (IQR) | 0.10 (0.01, 0.40) | 0.10 (0.01, 0.40) | 0.15 (0.02, 0.47) | 0.7 |
| Duration of surgery (min), mean (sd) | 167.9 (110.4) | 167.1 (111.7) | 172.6 (101.9) | 5.1 |
| Work RVU, median (IQR) | 14.5 (7.4, 20.8) | 14.1 (7.2, 20.8) | 16.7 (10.5, 21.8) | 14.9 |
| Service, no. (%) | ||||
| Orthopaedic surgery | 3818 (19.4) | 3166 (18.7) | 652 (23.1) | 10.8 |
| Vascular surgery | 2449 (12.4) | 1816 (10.8) | 633 (22.4) | 31.6 |
| Thoracic surgery | 2186 (11.1) | 1990 (11.8) | 196 (7.0) | –16.5 |
| Urology | 1560 (7.9) | 1359 (8.0) | 201 (7.1) | –3.4 |
| General surgery | 1378 (7.0) | 1234 (7.3) | 144 (5.1) | –9.1 |
| Anaesthesiology | 1233 (6.3) | 1132 (6.7) | 101 (3.6) | –14.1 |
| Neurosurgery | 1172 (6.0) | 1070 (6.3) | 102 (3.6) | –12.5 |
| Transplant | 1063 (5.4) | 949 (5.6) | 114 (4.0) | –7.5 |
| Acute care surgery | 991 (5.0) | 879 (5.2) | 112 (4.0) | –5.7 |
| Gynaecology | 490 (2.5) | 448 (2.7) | 42 (1.5) | –8.4 |
| Surgical oncology | 437 (2.2) | 408 (2.4) | 29 (1.0) | –10.9 |
| Plastic surgery | 336 (1.7) | 308 (1.8) | 28 (1.0) | –6.8 |
| Radiology | 241 (1.2) | 226 (1.3) | 15 (0.5) | –6.8 |
| ENT | 207 (1.1) | 188 (1.1) | 19 (0.7) | –4.2 |
| Colorectal | 159 (0.8) | 134 (0.8) | 25 (0.9) | 1.1 |
| Burn | 134 (0.7) | 134 (0.8) | 0 (0) | –12.7 |
| Other | 579 (2.9) | 519 (3.1) | 60 (2.1) | –6.3 |
| Missing | 1281 (6.5) | 933 (5.5) | 348 (12.3) | 24.1 |