Table 1.
Patient Characteristics
| Total Cohort | Propensity Score–Stratified Cohort | ||||
|---|---|---|---|---|---|
| Respiratory Culture Performed (n = 113) | Respiratory Culture Not Performed (n = 421) | P Value | Respiratory Culture Not Performed (n = 365) | P Value | |
| Demographics | |||||
| Male gender, No. (%) | 75 (66.4) | 239 (56.8) | .07 | 216 (59.2) | .19 |
| Age, mean (SD), y | 58.2 (14.6) | 57.7 (16.1) | .73 | 57.8 (16.1) | .76 |
| Caucasian race, No. (%) | 90 (79.7) | 309 (73.4) | .18 | 269 (73.7) | .22 |
| Comorbidities | |||||
| Charlson composite score, mean (SD) | 8.10 (4.23) | 7.93 (4.74) | .78 | 8.05 (4.23) | .92 |
| Congestive heart failure, No. (%) | 63 (55.8) | 223 (53.0) | .67 | 200 (54.8) | .91 |
| Cerebrovascular disease, No. (%) | 56 (49.6) | 156 (37.0) | .017 | 140 (38.4) | .04 |
| Chronic pulmonary disease, No. (%) | 50 (44.3) | 167 (39.7) | .39 | 143 (39.2) | .38 |
| Diabetes with chronic complications, No. (%) | 25 (22.1) | 95 (22.6) | 1 | 84 (23.0) | .9 |
| Paraplegia, No. (%) | 25 (22.1) | 56 (13.3) | .03 | 55 (15.1) | .08 |
| Moderate–severe liver disease, No. (%) | 10 (8.9) | 44 (10.5) | .73 | 38 (10.4) | .72 |
| Myocardial infarction, No. (%) | 45 (39.8) | 112 (26.6) | .008 | 110 (30.1) | .07 |
| Renal disease, No. (%) | 50 (44.3) | 205 (48.7) | .46 | 177 (48.5) | .45 |
| Tracheostomy, No. (%) | 31 (27.4) | 118 (28.0) | 1 | 94 (25.8) | .71 |
| Immunocompromised, No. (%) | 18 (15.9) | 75 (17.8) | .68 | 65 (17.8) | .78 |
| Health care exposures | |||||
| Length of stay before NATW, median (IQR), d | 4 (3–11) | 5 (3–12) | .43 | 4 (3–11) | .95 |
| Time on vent before NATW, median (range), d | 2 (2–29) | 2 (2–26) | .054 | 2 (2–26) | .12 |
| On antibiotics before event, No. (%) | 80 (70.8) | 328 (77.9) | .13 | 277 (75.9) | .32 |
| Prior pneumonia in last 3 mo, No. (%) | 9 (8.0) | 51 (12.1) | .24 | 40 (11.0) | .48 |
| MDRO in 1 y before NATW, No. (%) | 12 (10.6) | 64 (15.2) | .28 | 64 (15.2) | .28 |
| Acuity of illness | |||||
| APACHE score, mean (SD) | 21.8 (6.4) | 21.1 (6.8) | .28 | 21.4 (6.9) | .49 |
| P/F ratio, median (IQR) | 239.4 (176.6–325.6) | 249.6 (188.8–327.5) | .24 | 241.7 (183.88–315.3) | .55 |
| Abnormal temp, No. (%) | 84 (74.3) | 248 (58.9) | .003 | 239 (65.5) | .09 |
| Abnormal WBC, No. (%) | 79 (69.9) | 342 (81.2) | .013 | 292 (80.0) | .03 |
| Abnormal temp and WBC, No. (%) | 50 (44.3) | 169 (40.1) | .45 | 166 (45.5) | .83 |
NATW was defined as abnormal white blood cell count (>12 × 109/L or <4 × 109/L) OR temperature (>38°C or <36°C) with normal value in the preceding 36 hours. Immunocompromised was defined as history of solid organ transplant, hematopoietic stem cell transplant, hematologic malignancy within the past year, or receipt of immunosuppressing medications (steroids, anti–tumor necrosis factor therapy, mammalian target of rapamycin inhibitors, calcineurin inhibitors, antiproliferative agents). MDRO was defined as methicillin-resistant Staphylococcus aureus (on clinical or screening culture), vancomycin-resistant Enterococci (on clinical or screening culture), extended-spectrum β-lactamase-producing Enterobacterales, carbapenem-resistant Enterobacterales, carbapenemase-producing organisms, and Clostridioides difficile.
Abbreviations: APACHE, Acute Physiology and Chronic Health Evaluation; IQR, interquartile range; MDRO, multidrug-resistant organism; NATW, new abnormal temperature or white blood cell count; P/F ratio, partial pressure of oxygen/fraction of inspired oxygen; WBC, white blood cell.