Diagnosis of ECMO Cannula Infection: Prospective Comparison of Sampling Methods (ECMO-CSI-DIAG)

Diagnosis of ECMO Cannula Infection: a Prospective Comparison of Sampling Methods

Extracorporeal membrane oxygenation (ECMO) is increasingly used as rescue support in patients with refractory respiratory and/or circulatory failure. ECMO cannula site infection (ECMO-CSI) complicates approximately 10% of ECMO runs and is associated with septic shock, prolonged intensive care unit (ICU) stay and increased mortality. To date, there is neither a standardized definition nor consensus diagnostic criteria for ECMO-CSI, and the optimal microbiological sampling strategy, as well as the diagnostic accuracy of the available methods, remains undetermined.

This single-center, prospective, non-interventional study aims to compare the diagnostic accuracy of three microbiological sampling methods (superficial swab of the cannula insertion site, needle aspiration along the cannula tract, and cannula tip culture) for the diagnosis of ECMO-CSI in adult patients receiving veno-venous or veno-arterial ECMO.

A superficial swab and a needle aspirate will be obtained at each cannulation site on the day ECMO-CSI is clinically suspected and on the day of decannulation. In addition, the tip of each cannula will be cultured at decannulation. The results of these index tests will be compared with a reference diagnosis of ECMO-CSI established by an adjudication committee of expert clinicians blinded to the index test results.

A total of 500 patients will be enrolled in order to obtain at least 50 patients with adjudicated ECMO-CSI.

Study Overview

• Status: Not yet recruiting
• Conditions: Extracorporeal Membrane Oxygenation Complication; ECMO Cannula Infection

Detailed Description

BACKGROUND ECMO is a life-support technique widely used in refractory respiratory and/or circulatory failure. It is associated with infectious complications, notably cannula infections, whose incidence is estimated at about 10%. These infections are associated with an increased risk of septic shock and contribute to longer ICU stay and higher mortality. There is to date neither a standardized definition nor consensus diagnostic criteria, particularly regarding the nature and diagnostic performance of the microbiological samples to be collected. Superficial swabbing of the insertion site is simple and minimally invasive but frequently yields contaminated results or results reflecting colonizing flora. More invasive methods (needle aspiration, culture of the cannula tip at decannulation) may be more specific but are less commonly performed and have not been comparatively validated. A recent international Delphi consensus identified cannula aspiration and cannula swab as the two preferred microbiological methods. The lack of an established diagnostic algorithm leads to heterogeneous management, with potential consequences for antibiotic stewardship and patient outcomes.

DESIGN Single-center, prospective, non-interventional study conducted in the medical ICU of Pitié-Salpêtrière Hospital (AP-HP, Paris, France), which manages about 300 ECMO patients per year. All adult patients on veno-venous or veno-arterial ECMO are eligible. The patient (or trusted person, relative or legal representative) is informed and the patient is included unless an objection is expressed. Inclusion period: 24 months. Participation: duration of ICU stay (maximum 2 months). Total study duration: 26 months.

SAMPLING

• Swab (performed for the research): a sterile single-use swab is applied to the cannula insertion orifice.
• Needle aspiration (standard of care): 1 mL of sterile saline is injected along the cannula through a syringe and a plastic catheter, re-aspirated and transferred to a sterile container.
• Cannula tip (standard of care): at decannulation, the distal 5 cm of the cannula is cut with a sterile blade and placed in a sterile container.

On the day the clinician in charge suspects a cannulation site infection, a swab and a needle aspiration are performed at each cannulation site. On the day of decannulation, a swab and a needle aspiration are performed at each cannulation site and the tip of each cannula is sent for culture.

MICROBIOLOGY Samples are cultured in the microbiology laboratory using the Brun-Buisson technique: suspension in 1 mL of sterile saline and vortexing for about 1 minute, then 100 microliters are plated on fresh blood agar, chocolate agar and Sabouraud agar, incubated for 48 hours to 10 days under aerobic and anaerobic conditions and read daily. In case of positive culture, identification is performed by mass spectrometry (MALDI-TOF). Each sample is recorded as culture positive or culture negative.

REFERENCE STANDARD The reference diagnosis of ECMO cannula infection is the clinical diagnosis established by an adjudication committee of three clinician experts, ruling retrospectively and blinded to the results of the index tests, on the basis of the available clinical, biological, microbiological and outcome data.

DATA Data are collected prospectively from the electronic medical record into a REDCap electronic case report form hosted by AP-HP. At each sampling: local appearance of the insertion site (photograph), general and hemodynamic status, biological inflammatory markers, nosocomial infection during the stay, antibiotic therapy within the previous 7 days, rectal colonization with a multidrug-resistant organism, positive blood culture within the previous 48 to 72 hours, duration of ECMO support.

STATISTICS The sample size was set to obtain at least 50 cases of cannula infection; with an expected incidence of 10%, 500 patients will be included. Sensitivity, specificity and predictive values of each sampling strategy are computed against the reference diagnosis. Paired comparisons use the McNemar test. Agreement between methods is assessed with the kappa coefficient. Exploratory logistic regression analyses will identify factors associated with microbiological positivity. Analyses are performed on complete cases; a failed sampling technique is considered negative.

• Study Type: Observational
• Enrollment (Estimated): 500

Contacts and Locations

• Study Contact: Name: Charles-Edouard LUYT; Phone Number: +33 01 42 16 38 24; Email: charles-edouard.luyt@aphp.fr
• Study Contact Backup: Name: Laura WAKSELMAN; Phone Number: +33 01 42 16 19 50; Email: laura.wakselman@aphp.fr

Study Locations

• France
  • Paris, France
    • Hôpital Pitié Salpêtrière, Service de médecine intensive et réanimation
    • Contact: Charles-Edouard LUYT, MD, PhD; Phone Number: +33 01 42 16 38 24; Email: charles-edouard.luyt@aphp.fr
    • Contact: Laure FLURIN, MD, PhD; Phone Number: +33 01 84 82 79 76; Email: laure.flurin@aphp.fr
    • Principal Investigator: Charles Edouard LUYT, MD, PhD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Adult patients managed in the medical intensive care unit of Pitié-Salpêtrière Hospital (Paris, France) on veno-venous or veno-arterial ECMO during the inclusion period.

Description

Inclusion Criteria:

• Age >= 18 years
• Patient admitted to the intensive care unit with veno-venous or veno-arterial ECMO

Exclusion Criteria:

• Pregnant women
• Persons deprived of liberty
• Sample collection impossible for technical reasons
• Patients on central ECMO

Study Plan

How is the study designed?

Design Details

• Observational Models: COHORT
• Time Perspectives: PROSPECTIVE

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
Adult patients on ECMO; Adult patients on veno-venous or veno-arterial ECMO in the ICU. Swab and needle aspiration of each cannulation site on the day of clinical suspicion of cannula infection and on the day of decannulation; culture of each cannula tip at decannulation.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Diagnostic performance of each sampling strategy (superficial swab, needle aspiration, cannula tip culture) for the diagnosis of ECMO cannula infection	Sensitivity, specificity, positive and negative predictive values of each sampling strategy, and its agreement with the reference diagnosis of cannula infection established by the adjudication committee.	On the day of clinical suspicion of cannula infection and on the day of decannulation, up to ICU discharge (maximum 2 months)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Factors associated with positivity of the microbiological samples	Variables assessed at each sampling: weight (kg); height (meters), BMI (kg/m2), local appearance of the cannula insertion site on a photograph (purulence, inflammatory signs), fever (temperature (°C), systolic blood pressure (mmHg), diastolic blood pressure (mmHg), heart rate (bpm), noradrenaline (µg/kg/min), dobutamine (µg/kg/min)), biological criteria: hemoglobin (g/dL), white blood cell count (G/L), CRP (mg/L), PCT (ng/l), pH, bicarbonates (mmol/L), arterial lactate (mmol/L), nosocomial infection during the stay, antibiotic therapy within 7 days before sampling, rectal colonization with a multidrug-resistant organism, positive blood culture within 48 to 72 hours before sampling, positive culture of the ECMO cannula tip, duration of ECMO support.	On the day of clinical suspicion of cannula infection and on the day of decannulation, up to ICU discharge (maximum 2 months)
Agreement between the sampling methods	Agreement on culture positivity and on microbiological identification between swab, needle aspiration and cannula tip culture (kappa coefficient).	On the day of clinical suspicion of cannula infection and on the day of decannulation, up to ICU discharge (maximum 2 months)

Collaborators and Investigators

• Sponsor: Assistance Publique - Hôpitaux de Paris
• Investigators: Principal Investigator: Charles Edouard LUYT, MD, PhD, Assistance Publique - Hôpitaux de Paris

Study record dates

Study Major Dates

• Study Start (Estimated): November 1, 2026
• Primary Completion (Estimated): January 1, 2029
• Study Completion (Estimated): January 1, 2029

Study Registration Dates

• First Submitted: October 19, 2026
• First Submitted That Met QC Criteria: October 19, 2026
• First Posted (Actual): October 26, 2026

Study Record Updates

• Last Update Posted (Actual): November 6, 2026
• Last Update Submitted That Met QC Criteria: November 4, 2026
• Last Verified: November 1, 2026

More Information

Terms related to this study

• Keywords: ECMO; Diagnostic performance; swab; Needle aspiration; Cannula infection; Cannulation site infection; Cannula tip culture; microbiological sampling
• Other Study ID Numbers: APHP260913

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No