Article Figures & Data
Tables
- Table 1
Trauma center, patient and injury characteristics, and TT details by antibiotics status
No antibiotics* Antibiotics* P value† N 1615 (85.6) 272 (14.4) Age 45 (27, 59.5) 34 (24, 54) <0.01 Male 1249 (77.3) 214 (78.7) 0.68 Mechanism of injury Blunt 1207 (74.7) 162 (59.6) <0.01 Penetrating 408 (25.3) 110 (40.4) GCS on arrival Mild (13-15) 1157 (71.6) 210 (77.2) 0.12 Moderate (9-12) 78 (4.8) 8 (2.9) Severe (≤8) 380 (23.5) 54 (19.9) Intubation 761 (47.1) 100 (36.8) <0.01 ISS 0–14 727 (45) 117 (43) 0.80 16–24 420 (26) 75 (27.6) 25+ 468 (29) 80 (29.4) Indication for TT placement Hemothorax 313 (19.4) 60 (22.1) 0.15 Pneumothorax 788 (48.8) 141 (51.8) HPTX 514 (31.8) 71 (26.1) TT provider Attending 273 (16.9) 34 (12.5) 0.02 Other 1172 (72.6) 231 (84.9) Unknown 170 (10.5) 7 (2.6) TT location Emergency Department /trauma bay 1184 (73.3) 198 (72.8) <0.01 Floor 54 (3.3) 4 (1.5) ICU 211 (13.1) 28 (10.3) Operating room 113 (7) 41 (15.1) Unknown 53 (3.3) 1 (0.4) Trauma center designation American College of Surgeons verified trauma center 458 (28.4) 53 (19.5) 0.01 State 34 (2.1) 5 (1.8) Both 1123 (69.5) 214 (78.7) Trauma center level 1 1583 (98) 256 (94.1) <0.01 2 32 (2) 16 (5.9) Trauma center population Adult 614 (38) 103 (37.9) 0.14 Pediatric 17 (1.1) 7 (2.6) Both 984 (60.9) 162 (59.6) Trauma admissions per year <1500 208 (12.9) 37 (13.6) 0.08 1500–3000 1016 (62.9) 186 (68.4) >3000 391 (24.2) 49 (18) *Median (IQR) for continuous variables and count (percentage) for categorical variables.
†Fisher’s exact test or χ2 test for categorical variables and Wilcoxon rank-sum test for continuous variables; the unknown category, if present, is excluded from the testing procedure.
GCS, Glasgow Coma Score; HPTX, hemopneumothorax; ICU, intensive care unit; ISS, Injury Severity Score; TT, tube thoracostomy.
- Table 2
Comparison of outcome measures in the matched sample
No antibiotics* Antibiotics* P value† n=272 n=272 Empyema 4 (1.5) 6 (2.2) 0.75 Pneumonia 27 (9.9) 42 (15.4) 0.07 ICULOS 2 (0,6) 3 (0, 9) 0.02 Hospital LOS 7 (4,14) 8 (4,16) 0.31 Ventilation days 0 (0,3) 1 (0,5) 0.08 Death 29 (10.7) 24 (8.8) 0.58 Death or pneumonia 54 (19.9) 61 (22.4) 0.52 Clostridium difficile colitis 3 (1.1) 2 (0.7) >0.99 *Count (percentage) for binary outcomes and median (IQR) for count outcomes.
†McNemar’s test for binary outcomes and Wilcoxon signed-rank test for count outcomes.
ICU, intensive care unit length of stay.
- Table 3
Measure of association for primary and secondary outcomes
OR (95% CI) P value Empyema 1.51 (0.42 to 5.42) 0.53 Pneumonia 1.61 (0.86 to 3.03) 0.14 Death 0.55 (0.25 to 1.22) 0.14 Pneumonia or death 1.17 (0.77 to 1.77) 0.46 Clostridium difficile colitis 0.65 (0.09 to 4.48) 0.66 Rate ratio (95% CI) P value ICULOS 1.35 (0.93 to 1.96) 0.11 Hospital LOS 1.15 (0.95 to 1.40) 0.15 Ventilation days 1.43 (0.86 to 2.39) 0.17 Logistic regression for binary outcomes and negative binomial regression for count outcomes, both with random effects of matched pairs and trauma centers.
ICULOS, intensive care unit length of stay.
- Table 4
Sensitivity analysis: adjusted measures of association based on full cohort
OR (95% CI) P value Empyema 1.35 (0.58 to 3.16) 0.49 Pneumonia 1.54 (0.97 to 2.46) 0.07 Death 0.9 (0.45 to 1.81) 0.78 Pneumonia or death 1.31 (0.76 to 2.25) 0.32 Clostridium difficile colitis 0.58 (0.24 to 1.41) 0.23 Rate ratio (95% CI) P value ICULOS 1.34 (1.17 to 1.54) <0.0001 Hospital LOS 1.14 (1.05 to 1.23) 0.0019 Ventilation days 1.33 (1.01 to 1.75) 0.042 Adjusted estimates of marginal ORs and rate ratios based on generalized estimating equations fitted on the full cohort, with each trauma center treated as a cluster. CIs and p values were based on the robust SE.
ICULOS, intensive care unit length of stay.
- Table 5
Sensitivity analysis: adjusted measures of association based on full cohort
OR (95% CI) P value Empyema 1.35 (0.48 to 3.77) 0.56 Pneumonia 1.54 (0.97 to 2.46) 0.068 Death 0.9 (0.5 to 1.63) 0.74 Pneumonia or death 1.31 (0.86 to 2.01) 0.21 Clostridium difficile colitis 0.58 (0.12 to 2.87) 0.51 Rate ratio (95% CI) P value ICULOS 1.52 (1.24 to 1.87) 0.0001 Hospital LOS 1.18 (1.05 to 1.31) 0.0041 Ventilation Days 1.6 (1.19 to 2.15) 0.0016 Adjusted estimates of ORs and rate ratios based on generalized linear models fitted on the full cohort.
ICULOS, intensive care unit length of stay.
