TABLE 1.
Characteristics of the ICUs enrolled in this study, divided according to blood culture rate
| Characteristic | No. of ICUs |
P valuea | ||
|---|---|---|---|---|
| All (n = 223) | With blood culture rates below threshold (n = 145) | With blood culture rates above threshold (n = 78) | ||
| Type of ICU | ||||
| Interdisciplinary | 112 (50.2%) | 82 (56.6%) | 30 (38.5%) | 0.048 |
| Internal medicine | 47 (21.1%) | 25 (17.3%) | 22 (28.2%) | |
| Surgery | 41 (18.4%) | 26 (17.9%) | 15 (19.2%) | |
| Othersb | 23 (10.3%) | 12 (8.3%) | 11 (14.1%) | |
| Hospital size (beds)c | 500 (300–1,000) | 500 (300–800) | 800 (400–1,400) | <0.001 |
| Hospital type | ||||
| University | 37 (16.6%) | 13 (9.0%) | 24 (30.8%) | <0.001 |
| Academic teaching | 102 (45.7%) | 69 (47.6%) | 33 (42.3%) | |
| Nonacademic | 84 (37.7%) | 63 (43.5%) | 21 (26.9%) | |
| Own lab | 82 (36.8%) | 40 (27.6%) | 42 (53.8%) | <0.001 |
| Short-stay patientsd | ||||
| Less than 1/3 | 71 (31.8%) | 35 (24.1%) | 36 (46.2%) | 0.003 |
| 1/3 to 2/3 | 131 (58.8%) | 94 (64.8%) | 37 (47.4%) | |
| More than 2/3 | 21 (9.4%) | 16 (11.0%) | 5 (6.4%) | |
| Central line ratec | 67.3 (49.2–82.1%) | 62.5 (47.4–77.4%) | 74.5 (56.2–85.2%) | 0.006 |
| Ventilation ratec | 34.2 (22.7–49.9%) | 29.7 (21.5–44.5%) | 43.6 (32.9–56.1%) | <0.001 |
| Blood culture ratee | 60 (33–108) | 39 (25–59) | 131 (103–194) | <0.001 |
| Bloodstream infection ratee | 0.46 (0–1.19) | 0.42 (0–0.81) | 0.97 (0.34–1.72) | <0.001 |
| Bloodstream infection rate (CNS excluded)e | 0.38 (0–0.85) | 0.27 (0–0.68) | 0.65 (0.27–1.02) | <0.001 |
a
P values for the comparison between ICUs below and above the threshold using chi-square tests for categorical variables and Wilcoxon rank-sum tests for continuous variables.
b
Includes pediatrics (n = 3), neurology (n = 2), cardiology (n = 2), neurosurgery (n = 1), trauma unit (n = 1), burn unit (n = 1), heart surgery (n = 1).
c
Displayed are medians and interquartile ranges (in brackets).
d
Short stay patients are defined as having stayed less than 48 h at the ICU before discharge from ICU.
e
Per 1,000 patient-days at risk.