Objective: To study incidence, type, etiology, risk factors, and impact on outcome of nosocomial infections during extracorporeal membrane oxygenation. Design: Retrospective analysis of prospectively collected data. Setting: Italian tertiary referral center medical-surgical ICU. Patients: One hundred five consecutive patients who were treated with extracorporeal membrane oxygenation from January 2010 to November 2015. Interventions: None. Measurements and Main Results: Ninety-two patients were included in the analysis (48.5 [37–56] years old, simplified acute physiology score II 37 [32–47]) who underwent peripheral extracorporeal membrane oxygenation (87% veno-venous) for medical indications (78% acute respiratory distress syndrome). Fifty-two patients (55%) were infected (50.4 infections/1,000 person-days of extracorporeal membrane oxygenation). We identified 32 ventilator-associated pneumonia, eight urinary tract infections, five blood stream infections, three catheter-related blood stream infections, two colitis, one extracorporeal membrane oxygenation cannula infection, and one pulmonary-catheter infection. G+ infections (35%) occurred earlier compared with G– (48%) (4 [2–10] vs. 13 [7–23] days from extracorporeal membrane oxygenation initiation; p < 0.001). Multidrug-resistant organisms caused 56% of bacterial infections. Younger age (2–35 years old) was independently associated with higher risk for nosocomial infections. Twenty-nine patients (31.5%) died (13.0 deaths/1,000 person-days of extracorporeal membrane oxygenation). Infected patients had higher risk for death (18 vs. 8 deaths/1,000 person-days of extracorporeal membrane oxygenation; p = 0.037) and longer ICU stay (32.5 [19.5–78] vs. 19 [10.5–27.5] days; p = 0.003), mechanical ventilation (36.5 [20–80.5] vs. 16.5 [9–25.5] days; p < 0.001), and extracorporeal membrane oxygenation (25.5 [10.75–54] vs. 10 [5–13] days; p < 0.001). Older age (> 50 years old), reason for connection different from acute respiratory distress syndrome, higher simplified acute physiology score II, diagnosis of ventilator-associated pneumonia, and infection by multidrug-resistant bacteria were independently associated to increased death rate. Conclusions: Infections (especially ventilator-associated pneumonia) during extracorporeal membrane oxygenation therapy are common and frequently involve multidrug-resistant organisms. In addition, they have a negative impact on patients’ outcomes.

Rationale: We developed an innovative, minimally invasive, highly efficient extracorporeal CO2 removal (ECCO2R) technique called respiratory electrodialysis (R-ED). Objectives: To evaluate the efficacy of R-ED in controlling ventilation compared with conventional ECCO2R technology. Methods: Five mechanically ventilated swine were connected to a custom-made circuit optimized for R-ED, consisting of a hemofilter, a membrane lung, and an electrodialysis cell. Electrodialysis regionally modulates blood electrolyte concentration to convert bicarbonate to CO2 before entering the membrane lung, enhancing membrane lung CO2 extraction. All animals underwent three repeated experimental sequences, consisting of four steps: baseline (1 h), conventional ECCO2R (2 h), R-ED (2 h), and final NO-ECCO2R (1 h). Blood and gas flow were 250 ml/min and 10 L/min, respectively. Tidal volume was set at 8 ml/kg, and respiratory rate was adjusted to maintain arterial Pco2 at 50 mm Hg. Measurements and Main Results: During R-ED, chloride and H+ concentration increased in blood entering the membrane lung, almost doubling CO2 extraction compared with ECCO2R (112 ± 6 vs. 64 ± 5 ml/min, P < 0.001). Compared with baseline, R-ED and ECCO2R reduced minute ventilation by 50% and 27%, respectively. Systemic arterial gas analyses remained stable during the experimental phases. No major complication occurred, but there was an increase in creatinine level. Conclusions: In this first in vivo application, we proved electrodialysis feasible and effective in increasing membrane lung CO2 extraction. R-ED was more effective than conventional ECCO2R technology in controlling ventilation. Further studies are warranted to assess the safety profile of R-ED, especially regarding kidney function.