Table 2.
The ten most commonly isolated organisms, plus the uncommon drug-resistant ESBL-producing organisms and CPE, in descending order of isolate count from the old ICU
| Old ICU* |
New ICU† |
IRR (95% CI)¶ | p** | |||
|---|---|---|---|---|---|---|
| Isolate count | IR‡ | Isolate count | IR§ | |||
| Top ten organisms | ||||||
| 1. Coagulase-negative staphylococci | 399 | 27.1 | 300 | 17.3 | 0.64 (0.55–0.75) | < 0.01 |
| 2. Staphylococcus aureus | 254 | 17.2 | 320 | 18.5 | 1.07 (0.91–1.27) | 0.40 |
| Non-MRSA | 219 | 14.9 | 286 | 16.5 | 1.1 1 (0.93–1.33) | 0.24 |
| MRSA | 35 | 2.38 | 34 | 1.96 | 0.83 (0.50–1.37) | 0.43 |
| 3. Enterococcus species | 304 | 20.6 | 297 | 17.2 | 0.83 (0.71–0.98) | 0.02 |
| Non-VRE | 107 | 7.26 | 104 | 6.01 | 0.83 (0.63–1.09) | 0.10 |
| VRE (including surveillance) †† | 197 | 13.4 | 193 | 11.1 | 0.83 (0.68–1.02) | 0.07 |
| VRE (excluding surveillance) ‡‡ | 54 | 3.67 | 32 | 1.85 | 0.50 (0.32–0.80) | < 0.01 |
| 4. Escherichia coli | 155 | 10.5 | 204 | 11.8 | 1.12 (0.90–1.39) | 0.29 |
| 5. Klebsiella species | 135 | 9.16 | 117 | 6.76 | 0.74 (0.57–0.95) | 0.02 |
| 6. Enterobacter species | 104 | 7.06 | 119 | 6.88 | 0.97 (0.74–1.28) | 0.85 |
| 7. Haemophilus influenzae | 70 | 4.75 | 106 | 6.13 | 1.29 (0.94–1.77) | 0.10 |
| 8. Pseudomonas aeruginosa | 78 | 5.29 | 85 | 4.91 | 0.93 (0.67–1.28) | 0.63 |
| 9. Serratia marcescens | 39 | 2.65 | 42 | 2.43 | 0.79 (0.50–1.25) | 0.29 |
| 10. Streptococcus pneumoniae | 29 | 1.97 | 41 | 2.37 | 1.20 (0.73–2.00) | 0.45 |
| Other drug-resistant organisms | ||||||
| ESBL-producing organisms | 20 | 1.35 | 33 | 1.91 | 1.40 (0.78–2.58) | 0.23 |
| CPE | 3 | 0.20 | 3 | 0.17 | 0.85 (0.11–6.4) | 0.85 |
CPE = carbapenemase-producing Enterobacterales. ESBL = extended spectrum beta-lactamase. ICU = intensive care unit. IR = incidence rate. IRR = incidence rate ratio. MRSA = methicillin-resistant S. aureus. OBD = occupied bed days. VRE = vancomycin-resistant enterococci.
24-bed ICU used during the period 5 May 2014 to 4 May 2016.
32-bed ICU used during the period 5 May 2016 to 4 May 2018.
Incidence per 1000 OBD across 14734 OBD in the 2 years from 5 May 2014 to 4 May 2016.
Incidence per 1000 OBD across 17305 OBD in the 2 years from 5 May 2016 to 4 May 2018.
IRR of the new ICU compared with the old ICU.
Mid P values for tests of IR difference.
VRE isolates (including surveillance) in the old ICU were comprised of 35 (11.5%) VanA VRE, 142 (72.1%) VanB VRE, 13 (4.3%) VanA and VanB VRE and 7 (2.3%) unspecified VRE. VRE isolates (including surveillance) in the new ICU were comprised of 25 (13.0%) VanA VRE, 159 (81.3%) VanB VRE and 9 (4.7%) VanA and VanB VRE.
VRE isolates (excluding surveillance) in the old ICU were comprised of 11 (20.4%) VanA VRE, 41 (75.9%) VanB VRE, 1 (1.9%) VanA and VanB VRE and 1 (1.9%) unspecified VRE. VRE isolates (excluding surveillance) in the new ICU were comprised of 4 (12.5%) VanA VRE, 27 (84.4%) VanB VRE and 1 (3.1%) VanA and VanB VRE.