Gastrointestinal colonization with multidrug-resistant Gram-negative bacteria during extracorporeal membrane oxygenation: effect on the risk of subsequent infections and impact on patient outcome

Table 3 Univariable logistic regression analyzing risk factor for infection due to multidrug-resistant Gram-negative bacteria

Clinical characteristics	Infected (n = 37)	Non-infected (n = 54)	p	Odds ratio^a (95% CI)
Year
2010	5 (14%)	8 (15%)	0.970
2011	6 (16%)	8 (15%)
2012	4 (11%)	9 (17%)
2013	6 (16%)	9 (17%)
2014	8 (22%)	11 (20%)
2015	8 (22%)	9 (17%)
Age (years)	50 (37–55)	47 (36–58)	0.587	1.00 (0.98–1.03)
Gender (male)	28 (76%)	29 (54%)	0.030	2.68 (1.09–7.00)
Charlson Comorbidity Index	1 (0–3)	1 (0–3)	0.839	1.21 (0.17–7.82)
Transferred from peripheral hospital	32 (86%)	43 (80%)	0.393	1.63 (0.53–5.62)
IMV > 3 days prior to ECMO connection	22 (59%)	9 (17%)	0.001	7.33 (2.86–20.3)
RRT prior to ECMO connection	11 (30%)	4 (7%)	0.005	5.29 (1.63–20.6)
SOFA	8 (6–12)	8 (6–11)	0.348	1.05 (0.94–1.17)
SAPS II	38 (32–49)	37 (30–43)	0.806	1.00 (0.97–1.03)
ARDS	35 (95%)	37 (69%)	0.001	8.04 (2.09–53.0)
PaO₂/FiO₂ < 100 mmHg	32 (86%)	38 (70%)	0.066	2.69 (0.93–8.97)
Infection at admission	31 (84%)	33 (61%)	0.017	3.28 (1.22–9.93)
Chronic immunosuppression^b	8 (78%)	12 (78%)	0.946	0.96 (0.34–2.63)
Veno-venous support	34 (92%)	45 (83%)	0.223	2.26 (0.62–10.8)
Colonization	16 (43%)	3 (6%)	0.001	12.9 (3.83–59.9)

Data are presented as absolute frequency (% of the included patients) or as median and interquartile range
IMV invasive mechanical ventilation, ECMO extracorporeal membrane oxygenation, RRT renal replacement therapy, SOFA sequential organ failure assessment, SAPS II simplified acute physiology score, ARDS acute respiratory distress syndrome, ICU intensive care unit, LOS length of stay
^aOdds ratio of continuous variables are odds ratio per unit increase in variable
^bIncluding high-dosage corticosteroids, immunosuppressants or both. Statistically significant results are highlighted in italic