Table 1.
Main characteristics of patients with acute COPD exacerbation admitted to intensive care unit: overall and by ventilation strategy
| Variable | All Patients N = 3,520 |
Initial NIV N = 974 (27.7%) |
Initial IMV N = 1603 (45.5%) |
P-value* |
|---|---|---|---|---|
| Demographics | ||||
| Age, yr [median, IQR] | 67 [59, 74] | 67 [59, 75] | 66 [58, 74] | 0.014 |
| Male (n, %) | 1,610 (45.7) | 398 (40.9) | 752 (46.9) | 0.003 |
| Race (n, %) | ||||
| White | 2980 (84.7) | 803 (82.4) | 1,362 (85.0) | |
| Black | 446 (12.7) | 153 (15.7) | 188 (11.7) | 0.002 |
| Hispanic | 31 (0.9) | 10 (1.0) | 17 (1.1) | |
| Other/Unknown Race | 63 (1.8) | 8 (0.8) | 36 (2.2) | |
| Location Prior to ICU Admission n, % | ||||
| Emergency Department | 1778 (50.5) | 529 (54.3) | 765 (47.7) | |
| Other Hospital | 645 (18.3) | 84 (8.6) | 385 (24.0) | |
| Hospital ward | 547 (15.5) | 185 (19.0) | 222 (13.9) | |
| Step-down unit or Telemetry | 493 (14.0) | 157 (16.1) | 203(12.7) | <0.001 |
| ICU Transfer | 45 (1.3) | 15 (1.5) | 23 (1.4) | |
| Home/Other | 12 (0.3) | 4 (0.4) | 3 (0.2) | |
| Comorbidities | ||||
| Severe COPD | 1884 (53.5) | 530 (54.4) | 851 (53.1) | 0.51 |
| Immunosuppression | 220 (6.2) | 64 (6.6) | 84 (5.2) | 0.16 |
| Cirrhosis | 47 (1.3) | 13 (1.3) | 22 (1.4) | 0.93 |
| Cancer (any) | 136 (3.9) | 31 (3.2) | 70 (4.4) | 0.13 |
| Diabetes | 1338 (38.0) | 381 (39.1) | 640 (39.9) | 0.68 |
| Dialysis | 106 (3.0) | 36 (3.7) | 48 (3.0) | 0.33 |
| Advance directives | ||||
| No advance directive restriction | 1891, (N=2111) (89.6%) | 597 (N=684) (87.3) | 908 (N=991) (91.6) | 0.004 |
| Vitals | ||||
| RR (N = 3515) | 27 [14, 33] | N = 972 29 [23, 35] |
N = 1601 22 [12, 31] |
<0.001 |
| GCS (N = 2891) | 15 [13, 15] | N =957 15 [14, 15] |
N= 1006 13 [10, 15] |
<0.001 |
| ABG at admission | ||||
| FiO2 (N = 2591) | 45 [36, 60] | N = 736 40 [35, 50] |
N = 1419 50 [40, 80] |
<0.001 |
| PaO2 (N = 2591) | 82 [66, 120] | N = 736 76 [63, 94] |
N = 1419 94 [70, 155] |
<0.001 |
| PaCO2 mmHg (n = 2936) | 54 [41, 69] | N = 857 62 [46, 77] |
N = 1491 52 [42, 64] |
<0.001 |
| pH (N = 2591) | 7.35[7.29, 7.41] | N = 736 7.34 [7.29, 7.39] |
N = 1419 7.36 [7.29, 7.43] |
<0.001 |
| SAPS II score (n = 3518) | 37 [26, 51] | 34 [24, 44] | 44 [32, 58] | <0.001 |
| Hospital Characteristics | ||||
| Patients treated at a hospital with ≤400 beds | 1334 (37.9) | 380 (39.0) | 639 (39.9) | 0.66 |
| Number of ICU Beds | 20 [16, 26] | 18 [14, 30] | 20 [16, 26] | 0.001 |
| Patients treated at a Non-Teaching Hospital | 793 (22.5) | 270 (27.7) | 300 (18.7) | <0.001 |
Data are given as N (sample Size) and Percent or Median [25th percentile, 75th Percentile]
“All Patients” refers to all patients admitted to an ICU, meeting the inclusion criteria for COPD
*
p value compares initial NIV to initial IMV
Definition of abbreviations: ABG = arterial blood gases; FI O2 = fraction of inspired oxygen; NIV = noninvasive ventilation; PaCO2 = arterial carbon dioxide tension; SAPS = Simplified Acute Physiology Score, RR= respiratory rate, GCS = Glasgow coma score
Advance directives and vitals were not recorded consistently; the N equals the total number of patients with the variable recorded