TABLE 2.
Cross-Sectional Differences in Lung Ultrasound Findings by Severity at Baseline
| Oxygen Requirement Severity at Baseline Scan | Moderate: Ambient or Low-Flow Nasal Cannula (N = 169) | Moderately Severe: High-Flow Nasal Cannula or Noninvasive Positive Pressure Ventilation (N = 46) | Severe: Ventilation at LUS (N = 49) | p a |
|---|---|---|---|---|
| Age, yr, median (IQR) | 60.00 (46.00–68.00) | 63.00 (55.25–69.00) | 61.00 (53.00–67.00) | < 0.001 |
| Female, n (%) | 84 (49.70) | 18 (39.13) | 12 (24.49) | 0.006 |
| Race, n (%) | 0.232 | |||
| Asian | 1 (0.59) | 5 (10.87) | 1 (2.04) | |
| Black | 92 (54.44) | 18 (39.13) | 16 (32.65) | |
| White | 49 (28.99) | 15 (32.61) | 16 (32.65) | |
| Other | 26 (15.38) | 8 (17.39) | 15 (30.61) | |
| Ethnicity, n (%) | 0.445 | |||
| Hispanic | 25 (14.79) | 8 (17.39) | 11 (22.44) | |
| Non-Hispanic | 144 (85.21) | 38 (82.61) | 38 (77.55) | |
| Smoking, n (%) | 0.265 | |||
| Never | 103 (60.95) | 25 (54.34) | 21 (42.86) | |
| Current | 15 (8.88) | 3 (6.52) | 5 (10.20) | |
| Former | 48 (28.40) | 18 (39.13) | 14 (28.57) | |
| Median body mass index, kg/m2, median (IQR) | 27.56 (24.18–32.88) | 29.98 (26.75–33.17) | 30.80 (27.05–34.58) | 0.054 |
| Comorbidities, n (%) | ||||
| Cancer | 20 (11.83) | 0 (0.00) | 5 (10.20) | 0.051 |
| Congestive heart failure | 50 (29.59) | 15 (32.61) | 22 (44.90) | 0.141 |
| Chronic obstructive pulmonary disease | 65 (38.46) | 15 (32.61) | 16 (32.65) | 0.620 |
| Hypertension | 125 (73.96) | 35 (76.09) | 36 (73.47) | 0.957 |
| Liver disease | 32 (18.93) | 11 (23.91) | 11 (22.45) | 0.720 |
| Diabetes | 69 (40.83) | 19 (41.30) | 24 (48.98) | 0.605 |
| HIV/AIDS | 8 (4.73) | 4 (8.70) | 0 (0.00) | 0.126 |
| Symptoms onset until LUS scan, d, median (IQR) | 7.38 (4.08–11.22) | 9.29 (7.03–13.92) | 16.33 (11.08–28.29) | <0.001 |
| Physiologic variables, median (IQR) | ||||
| Respiratory rate (breaths/min, maximum value on day of ultrasound) | 20 (18–25) | 34 (27–42) | 28 (20–37) | < 0.001 |
| Heart rate, beats/min (maximum value on day of ultrasound) | 90 (80–100) | 87 (78–99) | 102 (90–116) | < 0.001 |
| Temperature (maximum value on day of ultrasound), °C | 36.9 (36.5–37.4) | 36.8 (36.5–37.1) | 37.2 (36.8–37.7) | 0.008 |
| Temperature (minimum value on day of ultrasound), °C | 36.0 (35.8–36.3) | 36.0 (35.8–36.2) | 36.3 (35.9–36.6) | 0.021 |
| WBC count (maximum value on day of ultrasound), × 109 cells/L | 6.64 (4.48–9.26) | 8.54 (6.77–9.76) | 11.19 (8.35–15.40) | < 0.001 |
| WBC count (minimum value on day of ultrasound), × 109 cells/L | 6.40 (4.48–9.07) | 8.24 (6.21–9.71) | 10.50 (7.09–14.37) | < 0.001 |
| Severe Inflammatory Response Syndrome (points) | 2 (1–2) | 2 (1–2) | 2 (2–3) | < 0.001 |
| Ultrasound variables, median (IQR) | ||||
| Mean LUS Score | 0.83 (0.33–1.17) | 1.11 (1.00–1.50) | 1.25 (1.00–1.67) | < 0.001 |
| A-line, % lung fields | 86 (67–100) | 70 (52–87) | 55 (25–67) | < 0.001 |
| B-line, % lung fields | 57 (27–75) | 82 (68–100) | 75 (60–100) | < 0.001 |
| Pleural effusion, % lung fields | 0 (0–8.3) | 0 (0–8.3) | 0 (0–37) | 0.10 |
| Pleural line abnormality, % lung fields | 0 (0–17) | 0 (0–16) | 25 (9–50) | < 0.001 |
IQR = interquartile range, LUS = lung ultrasound.
aKruskal-Wallis test by ranks.