Table 6.
Microorganisms causing O/S-SSI and I-SSI throughout the study
| Organisms isolated in O/S-SSI | P | ||||||
|---|---|---|---|---|---|---|---|
| Organisms | Overall | Baseline group | Bundle-1 | Bundle-2 | Baseline group (ref.) versus Bundle 1 | Baseline group (ref.) versus Bundle 2 | Bundle-1 (ref.) versus Bundle 2 |
| Number | 2910 | 2117 | 245 | 548 | |||
| Gram-positive bacteria | 632 (21.7) | 413 (19.5) | 75 (30.6) | 144 (26.3) | <0.001 | 0.001 | 0.229 |
| Enterococcus faecalis | 259 (8.9) | 164 (7.7) | 34 (13.9) | 61 (11.1) | 0.002 | 0.015 | 0.288 |
| Enterococcus faecium | 234 (8.0) | 151 (7.1) | 28 (11.4) | 55 (10.0) | 0.021 | 0.031 | 0.616 |
| Enterococcus spp. | 33 (1.1) | 27 (1.3) | 2 (0.8) | 4 (0.7) | 0.762 | 0.374 | 1.000 |
| Streptococcus spp. | 34 (1.2) | 25 (1.2) | 2 (0.8) | 7 (1.3) | 1.000 | 0.827 | 0.729 |
| MRSA | 13 (0.4) | 9 (0.4) | 2 (0.8) | 2 (0.4) | 0.319 | 1.000 | 0.591 |
| MSSA | 29 (1.0) | 20 (0.9) | 5 (2.0) | 4 (0.7) | 0.173 | 0.802 | 0.144 |
| Other GPB | 93 (3.2) | 62 (2.9) | 9 (3.7) | 22 (4.0) | 0.551 | 0.216 | 1.000 |
| Gram-negative bacteria | 1361 (46.8) | 1030 (48.7) | 106 (43.3) | 225 (41.1) | 0.120 | 0.002 | 0.586 |
| Escherichia coli | 714 (24.5) | 567 (26.8) | 54 (22.0) | 93 (17.0) | 0.125 | <0.001 | 0.093 |
| Klebsiella spp. | 5 (0.2) | 1 (0.0) | 1 (0.4) | 3 (0.5) | 0.197 | 0.029 | 1.000 |
| Pseudomonas spp. | 161 (5.5) | 128 (6.0) | 5 (2.0) | 28 (5.1) | 0.008 | 0.475 | 0.053 |
| Enterobacter spp. | 13 (0.4) | 9 (0.4) | 1 (0.4) | 3 (0.5) | 1.000 | 0.720 | 1.000 |
| Other GNB | 468 (16.1) | 325 (15.4) | 45 (18.4) | 98 (17.9) | 0.227 | 0.149 | 0.920 |
| Anaerobes | 94 (3.2) | 77 (3.6) | 9 (3.7) | 8 (1.5) | 1.000 | 0.009 | 0.062 |
| Bacteroides spp. | 74 (2.5) | 62 (2.9) | 8 (3.3) | 4 (0.7) | 0.693 | 0.002 | 0.011 |
| Clostridium spp. | 16 (0.5) | 13 (0.6) | 1 (0.4) | 2 (0.4) | 1.000 | 0.750 | 1.000 |
| Yeasts | 103 (3.5) | 54 (2.6) | 9 (3.7) | 40 (7.3) | 0.294 | <0.001 | 0.055 |
| Candida spp. | 103 (3.5) | 54 (2.6) | 9 (3.7) | 40 (7.3) | 0.294 | <0.001 | 0.055 |
| Organisms isolated in incisional-SSI | P | ||||||
|---|---|---|---|---|---|---|---|
| Organisms | Overall | Baseline group | Bundle-1 | Bundle-2 | Baseline group (ref.) versus Bundle 1 | Baseline group (ref.) versus Bundle 2 | Bundle-1 (ref.) versus Bundle 2 |
| Number | 2538 | 1979 | 217 | 342 | |||
| Gram-positive bacteria | 536 (21.1) | 390 (19.7) | 49 (22.6) | 97 (28.4) | 0.325 | <0.001 | 0.139 |
| Enterococcus faecalis | 214 (8.4) | 159 (8.0) | 24 (11.1) | 31 (9.1) | 0.153 | 0.522 | 0.468 |
| Enterococcus faecium | 76 (3.0) | 53 (2.7) | 6 (2.8) | 17 (5.0) | 0.827 | 0.038 | 0.275 |
| Enterococcus spp. | 19 (0.7) | 18 (0.9) | 1 (0.5) | 0 (0.0) | 1.000 | 0.094 | 0.388 |
| Streptococcus spp. | 42 (1.7) | 38 (1.9) | 0 (0.0) | 4 (1.2) | 0.028 | 0.508 | 0.161 |
| MRSA | 20 (0.8) | 15 (0.8) | 1 (0.5) | 4 (1.2) | 1.000 | 0.509 | 0.653 |
| MSSA | 106 (4.2) | 64 (3.2) | 14 (6.5) | 28 (8.2) | 0.031 | <0.001 | 0.512 |
| Other GPB | 207 (8.2) | 145 (7.3) | 17 (7.8) | 45 (13.2) | 0.784 | 0.001 | 0.054 |
| Gram-negative bacteria | 1327 (52.3) | 1051 (53.1) | 118 (54.4) | 158 (46.2) | 0.774 | 0.019 | 0.068 |
| Escherichia coli | 720 (28.4) | 596 (30.1) | 53 (24.4) | 71 (20.8) | 0.085 | <0.001 | 0.347 |
| Klebsiella spp. | 1 (0.0) | 0 (0.0) | 0 (0.0) | 1 (0.3) | 1.000 | 0.147 | 1.000 |
| Pseudomonas spp. | 176 (6.9) | 129 (6.5) | 22 (10.1) | 25 (7.3) | 0.064 | 0.558 | 0.274 |
| Enterobacter spp. | 8 (0.3) | 7 (0.4) | 0 (0.0) | 1 (0.3) | 1.000 | 1.000 | 1.000 |
| Other GNB | 422 (16.6) | 319 (16.1) | 43 (19.8) | 60 (17.5) | 0.177 | 0.526 | 0.504 |
| Anaerobes | 98 (3.9) | 85 (4.3) | 8 (3.7) | 5 (1.5) | 0.859 | 0.009 | 0.147 |
| Bacteroides spp. | 93 (3.7) | 82 (4.1) | 6 (2.8) | 5 (1.5) | 0.464 | 0.013 | 0.352 |
| Clostridium spp. | 4 (0.2) | 3 (0.2) | 1 (0.5) | 0 (0.0) | 0.341 | 1.000 | 0.388 |
| Yeasts | 22 (0.9) | 17 (0.9) | 1 (0.5) | 4 (1.2) | 1.000 | 0.537 | 0.653 |
| Candida spp. | 22 (0.9) | 17 (0.9) | 1 (0.5) | 4 (1.2) | 1.000 | 0.537 | 0.653 |
Values are n (%) unless otherwise indicated. O/S-SSI, organ/space-surgical site infection; MRSA, methicillin-resistant Staphylococcus aureus; MSSA, methicillin-sensitive Staphylococcus aureus; GPB, Gram-positive bacteria; GNB, Gram-negative bacteria.