Procedural details of patients with confirmed STEMI
| Characteristic | No supplemental oxygen exposure N=128 | Low supplemental oxygen exposure N=105 | Moderate supplemental oxygen exposure N=104 | High supplemental oxygen exposure N=104 | p Value |
|---|---|---|---|---|---|
| Status on arrival at the catheterisation laboratory | |||||
| Oxygen saturation, median (IQR) | 98 (97, 99) | 98 (96, 100) | 100 (98, 100) | 100 (99, 100) | <0.001 |
| Oxygen being administered, n (%) | 0 | 55 (52.4) | 85 (81.7) | 100 (96.2) | <0.001 |
| Oxygen flow rate (L/min), median (IQR) | 0 | 6 (4, 8) | 8 (6, 8) | 8 (6, 8) | <0.001 |
| Preintervention oxygen duration in minutes, median (IQR)* | 0 | 58 (49, 74) | 82 (62, 93) | 85 (68, 101) | <0.001 |
| Inotrope use, n (%) | 4 (3.1) | 5 (4.8) | 6 (5.8) | 8 (7.7) | 0.47 |
| Killip class ≥II, n (%) | 13 (10.7) | 9 (9.1) | 8 (8.2) | 20 (19.4) | 0.05 |
| Extent of coronary disease, n (%) | |||||
| LAD culprit artery | 38 (30.2) | 37 (35.6) | 39 (38.2) | 42 (40.8) | 0.37 |
| Multivessel disease | 76 (59.4) | 62 (59.0) | 56 (54.4) | 67 (64.4) | 0.54 |
| LMCA involvement | 4 (3.1) | 3 (2.9) | 5 (4.9) | 4 (3.8) | 0.87 |
| Procedural details, n (%) | |||||
| Preprocedural TIMI flow 0/1 | 106 (84.8) | 92 (92.0) | 92 (90.2) | 92 (88.5) | 0.36 |
| Postprocedural TIMI flow 2/3 | 122 (96.8) | 98 (95.1) | 100 (100.0) | 99 (96.1) | 0.21 |
| Radial intervention | 44 (34.6) | 34 (32.4) | 29 (28.2) | 40 (38.5) | 0.46 |
| Stent implanted | 118 (92.2) | 91 (86.7) | 98 (94.2) | 96 (92.3) | 0.24 |
| Drug-eluting stent | 65 (50.8) | 50 (47.6) | 61 (58.7) | 50 (48.1) | 0.35 |
| Glycoprotein IIb/IIIa inhibitor | 45 (35.2) | 42 (40.0) | 45 (43.3) | 55 (52.9) | 0.05 |
| Thrombus aspiration | 59 (46.1) | 44 (41.9) | 53 (51.0) | 56 (53.8) | 0.32 |
| Intra-aortic balloon pump | 4 (3.1) | 3 (2.9) | 4 (3.8) | 8 (7.7) | 0.27 |
| CABG | 2 (1.6) | 7 (6.7) | 1 (1.0) | 4 (3.8) | 0.07 |
| Symptom-to-intervention time, median (IQR) | 158 (128, 245) | 159 (124, 213) | 154 (124, 223) | 159 (128, 227) | 0.80 |
| Door-to-intervention time, median (IQR) | 54 (40, 70) | 52 (35, 66) | 56 (40, 69) | 58 (44, 70) | 0.32 |
| Length of stay (days), median (IQR) | 4 (3, 5) | 4 (3, 5) | 4 (4, 5) | 5 (4, 6) | <0.001 |
*Duration on oxygen therapy from randomisation to first procedural intervention (eg, aspiration, ballooning) measured in patients who received oxygen therapy.
CABG, coronary artery bypass grafting; LAD, left anterior descending; LMCA, left main coronary artery; RCA, right coronary artery; STEMI, ST-elevation myocardial infarction; TIMI, thrombolysis in myocardial infarction.