Table 2.
Adjusted incidence rate ratios (aIRR) of intervention versus baseline periods for the outcome CLABSI with any pathogen, CLABSI with gram-positive pathogens, CLABSI with CoNS and CLABSI with gram-negative bacteria according to study group (post-hoc analysis)
| Outcome | Chlorhexidine | Octenidine | Routine care (control arm) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| aIRR (95% CI) | P value | P value (Type III) | aIRR (95% CI) | P value | P value (Type III) | aIRR (95% CI) | P value | P value (Type III) | |
| CLABSI with any pathogen | |||||||||
| Baseline period | 1 = reference | 0.0172* | 1 = reference | 0.5111 | 1 = reference | 0.9190 | |||
| Intervention period | 0.63 (0.46–0.87) | 0.0055 | 1.17 (0.79–1.72) | 0.4394 | 0.98 (0.60–1.58) | 0.9193 | |||
| Mechanical ventilation use (per 1%) | 1.02 (1.01–1.03) | 0.0043 | 0.0420* | 1.01 (0.99–1.02) | 0.3808 | 0.4730 | 1.02 (0.99–1.04) | 0.1505 | 0.1589 |
| Length of stay (per 1 day) | 0.98 (0.87–1.10) | 0.6778 | 0.6712 | 1.14 (1.06–1.22) | 0.0003 | 0.1134 | 1.01 (0.89–1.15) | 0.8716 | 0.8754 |
| CLABSI with gram-positive bacteria | |||||||||
| Baseline period | 1 = reference | 0.0580 | 1 = reference | 0.3077 | 1 = reference | 0.9610 | |||
| Intervention period | 0.55 (0.34–0.90) | 0.0176 | 1.46 (0.86–2.50) | 0.1651 | 0.99 (0.55–1.78) | 0.9607 | |||
| Mechanical ventilation use (per 1%) | 1.02 (1.00–1.03) | 0.0280 | 0.0730 | 1.00 (0.99–1.02) | 0.5746 | 0.6239 | 1.02 (0.99–1.04) | 0.1495 | 0.1973 |
| Length of stay (per 1 day) | 0.94 (0.86–1.04) | 0.2440 | 0.2920 | 1.11 (0.98–1.25) | 0.1172 | 0.2663 | 1.04 (0.92–1.18) | 0.5404 | 0.5173 |
| CLABSI with CoNS | |||||||||
| Baseline period | 1 = reference | 0.0359* | 1 = reference | 0.4452 | 1 = reference | 0.9252 | |||
| Intervention period | 0.38 (0.19–0.74) | 0.0043 | 1.62 (0.63–4.17) | 0.3134 | 1.02 (0.64–1.65) | 0.9257 | |||
| Mechanical ventilation use (per 1%) | 1.03 (1–1.05) | 0.0295 | 0.0990 | 1.01 (0.99–1.02) | 0.2205 | 0.2804 | 1.02 (1–1.04) | 0.0604 | 0.1473 |
| Length of stay (per 1 day) | 0.95 (0.88–1.03) | 0.1786 | 0.2959 | 1.05 (0.87–1.27) | 0.6020 | 0.6692 | 1.01 (0.88–1.17) | 0.8531 | 0.8592 |
| CLABSI with gram-negative bacteria | |||||||||
| Baseline period | 1 = reference | 0.6008 | 1 = reference | 0.4507 | 1 = reference | 0.2151 | |||
| Intervention period | 0.79 (0.34–1.84) | 0.5825 | 0.79 (0.46–1.37) | 0.4067 | 1.5 (0.95–2.37) | 0.0792 | |||
| Mechanical ventilation use (per 1%) | 1.01 (0.98–1.04) | 0.4426 | 0.5020 | 1 (0.98–1.03) | 0.7811 | 0.7880 | 1.01 (0.97–1.04) | 0.7374 | 0.7262 |
| Length of stay (per 1 day) | 1.07 (0.95–1.21) | 0.2633 | 0.3005 | 1.28 (1.2–1.36) | < .0001 | 0.0313 | 1.05 (0.82–1.36) | 0.6844 | 0.7248 |
CLABSI, central line associated bloodstream infection. 95% CI, 95% confidence interval. aIRR, adjusted incidence rate ratios. GEE, generalised estimated equation model. Separate GEE models were based on monthly aggregated data, negative binomial distribution, accounted for clustering effects and were calculated with the log number of CL days as offset variable. Parameters considered in all models were mechanical ventilation use and length of stay. * P values (type III test) < 0.05 were considered significant