Table 1.
Baseline centeracteristics of the patients in HiLo‐HF trial and registry
| HiLo registry (n = 60) | HiLo pilot RCT | ||||
|---|---|---|---|---|---|
| All (n = 50) | High SpO2 target (n = 25) | Low SpO2 target (n = 25) | P‐value | ||
| Age, year | 77 (65.5, 86) | 73.5 (67, 84) | 73.0 (70, 77) | 74 (59, 86) | 0.75 |
| Women, n (%) | 21 (35) | 21 (42) | 11 (44) | 10 (40) | 0.77 |
| Race | |||||
| Aboriginal | 1 (1.7) | 1 (2) | 0 (0) | 1 (4) | 0.14 |
| Caucasian | 49 (81.7) | 39 (78) | 20 (80) | 19 (76) | 0.73 |
| Other | 10 (16.6) | 10 (20) | 5 (20) | 5 (20) | 0.27 |
| Medical history | |||||
| Heart failure | 34 (56.7) | 35 (70) | 15 (60) | 20 (80) | 0.12 |
| Ischaemic | 21 (35) | 22 (44) | 9 (36) | 13 (52) | 0.25 |
| Non‐ischaemic | 13 (21.7) | 13 (26) | 6 (24) | 7 (28) | |
| AF/flutter | 35 (58.3) | 26 (52) | 12 (48) | 14 (56) | 0.57 |
| Cardiac devicesa | 11 (18.3) | 10 (20) | 5 (20) | 5 (20) | 1.00 |
| CAD | 26 (43.3) | 28 (56) | 14 (56) | 14 (56) | 1.00 |
| MI | 11 (42.3) | 14 (50) | 8 (57.1) | 6 (42.9) | 0.45 |
| PCI | 11 (42.3) | 10 (35.7) | 4 (28.6) | 6 (42.9) | 0.43 |
| CABG | 11 (42.3) | 9 (32.1) | 5 (35.7) | 4 (28.6) | 0.68 |
| Prior stroke | 15 (25) | 10 (20.4) | 6 (25) | 4 (16) | 0.43 |
| Diabetes | 21 (35) | 22 (44) | 8 (32) | 14 (56) | 0.08 |
| HTN | 45(75) | 35 (70) | 16 (64) | 19 (76) | 0.35 |
| COPD | 19 (31.7) | 9 (18) | 6 (24) | 3 (12) | 0.27 |
| Asthma | 2 (3.3) | 0 (0) | 0 (0) | 0 (0) | n/a |
| Smoking | 36 (60) | 31 (62) | 18 (72) | 13 (52) | 0.14 |
| Current | 4 (11.1) | 9 (29) | 6 (33.3) | 3 (23.1) | 0.53 |
| Pack/year | 20 (7.3, 38.8) | 27.5 (10, 40) | 33.8 (12.5, 45) | 25.0 (6.3, 31) | 0.14 |
| Cancer within past 5 years | 11 (18.3) | 4 (8) | 2 (8) | 2 (8) | 1.00 |
| Charlson Index | 4 (3.5, 6) | 4 (3, 6) | 4 (3, 5) | 5 (4, 6) | 0.10 |
| Baseline LVEF, n (%) | 0.33 | ||||
| ≤20% | 8 (13.3) | 4 (8) | 1 (4) | 3 (12) | |
| 21–40% | 12 (20) | 20 (40) | 9 (36) | 11 (44) | |
| 41–45% | 7 (11.7) | 3 (6) | 3 (12) | 0 (0) | |
| 46–50% | 3 (5) | 5 (10) | 3 (12) | 2 (8) | |
| ≥51% | 24 (40) | 16 (32) | 9 (36) | 7 (28) | |
| Missing | 6 (10) | 2 (4) | 0 (0) | 2 (8) | |
| Mode of ED arrival, n (%) | 0.59 | ||||
| Direct admission from clinic | 1 (1.7) | 1 (2) | 0 (0) | 1 (4) | |
| Self‐presentation | 30 (50) | 27 (54) | 14 (56) | 13 (52) | |
| EMS | 29 (48.3) | 22 (44) | 11 (44) | 11 (44) | |
| O2 in EMS, n (%) | 16 (55.2) | 12 (54.5) | 7 (63.6) | 5 (45.5) | 0.39 |
| O2 in EMS, L/min | 2.0 (2, 4) | 5.5 (3, 7) | 5.5 (4, 8) | 4.0 (2, 6) | 0.61 |
| Pre‐randomization SpO2, % | 95 (93, 97) | 94.5 (93, 97) | 94 (92, 96) | 96 (93, 98) | 0.12 |
| Pre‐randomization O2, n (%) | 26 (43.3) | 21 (42) | 11 (44) | 10 (40) | 0.77 |
| Pre‐randomization O2, L/min | 2 (2, 3.2) | 2 (2, 3) | 2 (2, 3) | 2.2 (2, 4) | 0.37 |
| Time | |||||
| From triage to admission order, h | 11.2 (8, 13.8) | 7.2 (5, 11.7) | 7.5 (4.7, 11.7) | 7.0 (5.1, 10.6) | 0.67 |
| From triage to enrolment, h | 19.2 (7.2, 21.5) | 11.4 (7.3, 13.5) | 11.4 (6.2, 13.5) | 11.3 (8.1, 14.2) | 0.47 |
| From triage to first NT‐proBNP test, h | — | 13.2 (8.0, 15.3) | 13.1 (7.5, 15.4) | 13.2 (8.2, 15.3) | 0.44 |
| From triage to disposition from ED, h | 16.2 (11.3, 21.8) | 12.8 (9, 15.7) | 12.7 (6.6, 15.3) | 14.6 (9.4, 16.8) | 0.24 |
| From triage to discharge from hospital, days | 6 (2.8, 12.4) | 6.3 (3.7, 11) | 4.7 (2.7, 6.7) | 9.5 (4.9, 19.9) | 0.01 |
Note: AF, atrial fibrillation; CABG, coronary artery bypass grafting; CAD, coronary artery disease; COPD, chronic obstructive pulmonary disease; ED, emergency department; EMS, emergency medical services; HiLo, high‐dose oxygen/low‐dose oxygen; HTN, hypertension; MI, myocardial infarction; NT‐proBNP, N‐terminal pro‐brain‐type natriuretic peptide; O2, oxygen; PCI, percutaneous coronary intervention; SpO2, peripheral oxygen saturation level.
a
Cardiac devices including pacemaker, implantable cardioverter defibrillator, and cardiac resynchronization therapy. Unless described otherwise, median (25th percentile, 75th percentile) are reported.