Table 1.
Demographic and clinical characteristics of study cohort in MIMIC III
| Overall (n = 10,431) |
VAP group (n = 212) |
Non-VAP group (n = 10,219) |
p value | |
|---|---|---|---|---|
| Age(years), median(IQR) | 66.3 (53.1–76.0) | 66.3 (52.1–77.8) | 66.3 (53.1–76.0) | 0.387 |
| Gender, n(%) | 0.107 | |||
| Male | 5937 (56.9) | 109 (51.4) | 5828 (57.0) | |
| Female | 4494 (43.1) | 103 (48.6) | 4391 (43.0) | |
| Admission source, n(%) | < 0.001 | |||
| MICU | 4089 (39.2) | 154 (72.6) | 3935 (38.5) | |
| Other ICU | 6342 (60.8) | 58 (27.4) | 6284 (61.5) | |
| Admission type, n(%) | < 0.001 | |||
| Emergency | 9504 (91.1) | 211 (99.5) | 9293 (90.9) | |
| Elective | 927 (8.9) | 1 (0.5) | 926 (9.1) | |
| Reintubation, n(%) | 3294 (31.6%) | 65 (30.7%) | 3229 (30.6%) | 0.823 |
| Pre-existing Diseases, n(%) | ||||
| COPD | 101 (1.0%) | 2 (0.9%) | 99 (1.0) | 1.0 |
| Diabetes | 2698 (25.9) | 60 (28.3) | 2638 (25.8) | 0.428 |
| Hypertension | 4943 (47.4) | 80 (37.7) | 4863 (47.6) | 0.004 |
| Solid tumor | 313 (3.0) | 8 (3.8) | 305 (3.0) | 0.537 |
| Metastatic tumor | 418 (4.0) | 5 (2.4) | 413 (4.0) | 0.286 |
| Renal failure | 1721 (16.5) | 26 (12.3) | 1695 (16.6) | 0.111 |
| Liver failure | 1653 (15.9) | 22 (10.4) | 1631 (16.0) | 0.028 |
| PaO2/FiO2, median(IQR) | 240.0 (178.5–315.4) | 194.17 (150.0–256.5) | 241.0 (179.4–316.7) | < 0.001 |
| WBC(K/uL), median(IQR) | 12.8 (9.2–17.7) | 13.2 (9.8–18.0) | 12.8 (9.2–17.7) | 0.121 |
| Body temperature(℃), median(IQR) | 37.8 (37.3–38.4) | 37.9 (37.3–38.6) | 37.8 (37.3–38.4) | 0.255 |
| APACHE III score, median(IQR) | 50.0 (37.0–66.0) | 53.0 (40.75–64.0) | 50.0 (37.0–66.0) | 0.031 |
| HR | 5.0 (0.0–7.0) | 5.0 (0.0–7.0) | 5.0 (0.0–7.0) | 0.028 |
| MAP | 15.0 (7.0–15.0) | 15.0 (7.0–15.0) | 15.0 (7.0–15.0) | 0.197 |
| Temperature | 0.0 (0.0–2.0) | 0.0 (0.0–2.0) | 0.0 (0.0–2.0) | < 0.001 |
| RR | 6.0 (0.0–6.0) | 6.0 (0.0–9.0) | 6.0 (0.0–6.0) | 0.001 |
| A-aDO2/PaO2 | 0.0 (0.0–0.0) | 0.0 (0.0–0.0) | 0.0 (0.0–0.0) | < 0.001 |
| Hematocrit | 3.0 (3.0–3.0) | 3.0 (3.0–3.0) | 3.0 (3.0–3.0) | 0.269 |
| WBC | 0.0 (0.0–1.0) | 0.0 (0.0–1.0) | 0.0 (0.0–1.0) | 0.083 |
| Creatinine | 0.0 (0.0–7.0) | 0.0 (0.0–7.0) | 0.0 (0.0–7.0) | 0.484 |
| UO | 5.0 (0.0–7.0) | 5.0 (0.0–7.0) | 5.0 (0.0–7.0) | 0.013 |
| BUN | 7.0 (2.0–11.0) | 7.0 (2.0–11.0) | 7.0 (2.0–11.0) | 0.094 |
| Sodium | 0.0 (0.0–2.0) | 0.0 (0.0–2.0) | 0.0 (0.0–2.0) | 0.016 |
| ALB | 0.0 (0.0–6.0) | 0.0 (0.0–6.0) | 0.0 (0.0–6.0) | 0.087 |
| Bilirubin | 0.0 (0.0–0.0) | 0.0 (0.0–0.0) | 0.0 (0.0–0.0) | 0.008 |
| Glucose | 0.0 (0.0–3.0) | 3.0 (0.0–3.0) | 0.0 (0.0–3.0) | 0.017 |
| Acid–base | 3.0 (1.0–6.0) | 3.0 (1.0–5.0) | 3.0 (1.0–6.0) | 0.077 |
| GCS | 0.0 (0.0–0.0) | 0.0 (0.0–0.0) | 0.0 (0.0–0.0) | 0.017 |
| SOFA score, median(IQR) | 6.0 (4.0–9.0) | 6.0 (4.0–8.0) | 6.0 (4.0–9.0) | 0.034 |
| Respiration | 3.0 (0.0–3.0) | 3.0 (2.0–3.0) | 3.0 (0.0–3.0) | 0.014 |
| Coagulation | 0.0 (0.0–1.0) | 0.0 (0.0–1.0) | 0.0 (0.0–1.0) | < 0.001 |
| Liver | 0.0 (0.0–1.0) | 0.0 (0.0–0.0) | 0.0 (0.0–1.0) | 0.004 |
| Cardiovascular | 1.0 (1.0–3.0) | 1.0 (1.0–3.0) | 1.0 (1.0–3.0) | 0.022 |
| CNS | 0.0 (0.0–1.0) | 0.0 (0.0–0.0) | 0.0 (0.0–1.0) | 0.008 |
| Renal | 1.0 (0.0–2.0) | 1.0 (0.0–2.0) | 1.0 (0.0–2.0) | 0.471 |
| Coma adm, n(%) | 6 (0.1%) | 0 (0.0%) | 6 (0.1%) | 1.0 |
| Aspiration adm, n(%) | 32 (0.3%) | 4 (1.9%) | 28 (0.3%) | 0.004 |
| Sepsis adm, n(%) | 548 (5.3%) | 10 (4.7%) | 538 (5.3%) | 0.876 |
| Bacteremia adm, n(%) | 11 (0.1%) | 0 (0.0%) | 11 (0.1%) | 1.0 |
| Trauma adm, n(%) | 202 (1.9%) | 0 (0.0%) | 202 (2.0%) | 0.037 |
| Polytrauma adm, n(%) | 45 (0.4%) | 0 (0.0%) | 45 (0.4%) | 1.0 |
| Fracture adm, n(%) | 27 (0.3%) | 0 (0.0%) | 27 (0.3%) | 1.0 |
| Pneumothorax adm, n(%) | 19 (0.2%) | 0 (0.0%) | 19 (0.2%) | 1.0 |
MICU medical intensive care unit, APACHE III Acute Physiology and Chronic Health Evaluation III, PaO2/FiO2 the partial pressure of arterial oxygen/ fraction of inspired oxygen, WBC white blood cell count, HR heart rate, MAP mean arterial pressure, RR respiratory rate, A-aDO2/PaO2 pulmonary alveolus-arterial difference of oxygen pressure/ partial pressure of oxygen, UO urine output, BUN blood urea nitrogen, ALB albumin, GCS Glasgow Coma Scale, SOFA sequential organ failure assessment, CNS central nervous system, COPD chronic obstructive pulmonary disease, adm admission