Table 4.
Performance of CXR, LUS, and procalcitonin at inclusion for diagnosis of VAP (mini-BAL culture-confirmed)
| Parameters | Sensitivity | Specificity | PPV | NPV | LR+ | LR- |
|---|---|---|---|---|---|---|
| CXR 1 | 72.5 (61.4–81.9) | 26.7 (12.3–45.9) | 72.5 (61.4–81.9) | 26.7 (12.3–45.9) | 0.9 (0.8–1.3) | 1.03 (0.5–2.1) |
| CXR 2 | 27.5 (18.1–38.6) | 73.3 (54.1–87.7) | 73.3 (54.1–87.7) | 27.5 (18.1–38.6) | 1.03 (0.5–2.1) | 0.9 (0.8–1.3) |
| LUS1 | 87.1 (78–93.4) | 56 (34.9–75.6) | 87.1 (78–93.4) | 56 (34.9–75.6) | 1.9 (1.3–3.1) | 0.2 (0.1–0.4) |
| LUS 2 | 42.8 (31.6–54.7) | 91.7 (61.5–99.8) | 97.1 (84.7–99.9) | 20 (10.4–32.9) | 5.1 (0.8–34.2) | 0.62 (0.5–0.8) |
| LUS overall | 91.3 (82.8–96.4) | 70 (50.6–85.3) | 89 (80.2–94.9) | 75 (55.1–89.3) | 3 (1.8–5.3) | 0.1 (0.1–0.3) |
| Procalcitonin = 1 ng/dL (n = 98) | 59.7 (47.5–71.1) | 15.4 (4.4–37.9) | 66.2 (53.4–77.4) | 12.1 (3.4–28.2) | 0.7 (0.6–0.9) | 2.6 (1–6.7) |
Notes: Data are presented as % (95% CI). CXR, chest X-ray; CXR 1, diffuse infiltrate; CXR 2, localized infiltrate; LR+, positive likelihood ratio; LR-, negative likelihood ratio; LUS, lung ultrasound, LUS1, LUS 2 (Table 1 for detail); NPV, negative predictive value; PPV, positive predictive value; VAP, ventilator-associated pneumonia