Microbial adhesion on membrane oxygenators in patients requiring extracorporeal life support detected by a universal
Christian Kuehn1, Peter Orszag, Karin Burgwitz
1Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Hannover, Germany. kuehn.christian@mh-hannover.de
Abstract:
Extracorporeal membrane oxygenation (ECMO) represents a temporary life-saving therapy for respiratory or circulatory failure, but infections during ECMO support are a life-threatening complication. Surface-related infections of ECMO are mentioned, but rarely described in the literature. A universal rDNA polymerase chain reaction (PCR) test was used to investigate the potential microbiological colonization of membrane oxygenators (MOs) in 20 patients undergoing ECMO. The overall patient-based positivity by PCR was 45%. Gram-positive bacteria (71%) represented the most abundant microorganisms on MO surfaces, followed by Gram-negative bacteria (22%) and fungi (7%). The most frequently detected causative pathogens were staphylococci (58%). Bacterial mixed infections represented 56% of all infections. In four PCR-positive cases, the pathogens detected on the MO surfaces were also found by blood culture or by culture of specimens obtained from the infectious focus. In conclusion, hollow fiber membranes of MOs can be colonized by microorganisms and appear to be a potential source of bacterial and fungal infections in ECMO patients. These infections may pose an increased risk for clinical worsening. As a consequence, persistent septic complications have to be discussed as an indication for MO exchange. The initial results suggest that the applied PCR assay is a valuable tool to investigate MOs.
Insights
Membrane oxygenators (MOs) used in extracorporeal membrane oxygenation (ECMO) can become colonized by bacteria and fungi. This colonization may lead to life-threatening infections in ECMO patients, warranting further investigation and potential MO exchange.
Area of Science:
- Critical Care Medicine
- Infectious Diseases
- Biotechnology
Background:
- Extracorporeal membrane oxygenation (ECMO) is a vital therapy for severe respiratory or circulatory failure.
- Infections during ECMO support are a significant threat, with surface-related infections of ECMO devices being poorly described.
- Membrane oxygenators (MOs) are critical components of ECMO circuits.
Purpose of the Study:
- To investigate the microbiological colonization of MOs in patients undergoing ECMO.
- To determine the prevalence and types of microorganisms colonizing MO surfaces.
- To assess the potential of MOs as a source of infection in ECMO patients.
Main Methods:
- A universal rDNA polymerase chain reaction (PCR) assay was employed.
- MOs from 20 ECMO patients were analyzed for microbial colonization.
- Results were correlated with blood cultures and clinical infectious foci.
Main Results:
- 45% of patients showed microbial colonization on their MOs.
- Gram-positive bacteria (71%) were the most prevalent, followed by Gram-negative bacteria (22%) and fungi (7%).
- Staphylococci were the most common pathogens (58%), with 56% of infections being polymicrobial.
Conclusions:
- Hollow fiber membranes of MOs can harbor microorganisms, serving as a potential source for infections in ECMO patients.
- MO colonization poses an increased risk for clinical deterioration and persistent septic complications.
- The PCR assay is a valuable tool for investigating MO colonization and guiding clinical decisions, including MO exchange.
