Predictors of insufficient peak amikacin concentration in critically ill patients on extracorporeal membrane oxygenation

Practices surrounding antimicrobial use in patients managed with extracorporeal membrane oxygenation: An international survey

PURPOSE

This study aimed to survey critical care clinicians and characterize their perception of antimicrobial dosing strategies in patients receiving extracorporeal membrane oxygenation (ECMO).

METHODS

International, cross-sectional survey distributed to members of the Society of Critical Care Medicine in October 2022.

RESULTS

Respondents were primarily physicians (45%), with 92% practicing in North America. Ninety-seven percent of respondents reported antimicrobial dosing in critically ill patients to be challenging, due to physiological derangements seen in the patient population. Eighty-seven percent reported consideration of physicochemical drug properties when dosing antimicrobials in ECMO-supported patients, with lipophilicity (83%) and degree of protein binding (74%) being the two most common. Respondents' approach to antimicrobial dosing strategies did not significantly differ in critically ill ECMO-supported patients, compared to patients with equal severity of illness not receiving ECMO support.

CONCLUSION

Approaches to antimicrobial dosing strategies do not significantly differ among respondents between critically ill patients on ECMO support, compared to patients with equal severity of illness not receiving ECMO support. These findings were unexpected considering the added physiologic complexity of the ECMO circuit to critically ill adult patients and the need for well designed and adequately powered studies to inform empiric dosing guidance for ECMO-supported patients.

Daily fluid intake as a novel covariate affecting the population pharmacokinetics of polymyxin B in patients with sepsis

BACKGROUND

Polymyxin B dosing in patients with sepsis is difficult because pathophysiological changes and supportive therapies alter drug pharmacokinetics (PK). This study aimed to investigate the impact of fluid management and renal function on the PK of polymyxin B and to propose alternative dosing regimens.

METHODS

Patients (aged ≥ 18 y) with sepsis and receiving intravenous polymyxin B for ≥ 96 h were enrolled. Blood samples were collected at steady state. Plasma concentrations were measured by liquid chromatography-tandem mass spectrometry and subjected to population PK modelling. Monte Carlo simulations were used to optimise dosage regimens.

RESULTS

Eighty-three patients with a median (range) daily fluid intake of 4.2 (1.3-8.4) L and a creatinine clearance (CrCL) of 87.5 (17.3-309.7) mL/min were included. Polymyxin B PK was adequately characterised by a two-compartment model. The PK covariate analysis revealed daily fluid intake statistically significantly affected central volume of distribution and central compartment clearance (CL), and CrCL influenced CL. Simulation indicated that a decreased dosing would be suitable for patients with renal dysfunction (CrCL < 40 mL/min), and therapeutic drug monitoring is recommended to avoid exposure fluctuation when patients have fluid overload.

CONCLUSIONS

Fluid management as well as renal function are essential factors affecting polymyxin B PK for patients with sepsis, which can help optimise dosage regimens.

Systematic review of high-dose amikacin regimens for the treatment of Gram-negative infections based on EUCAST dosing recommendations

BACKGROUND

Updated European Committee on Antimicrobial Susceptibility Testing (EUCAST) amikacin breakpoints for Enterobacterales and Pseudomonas aeruginosa included revised dosing recommendations of 25-30 mg/kg to achieve key pharmacokinetic/pharmacodynamic parameters, higher than recommended in the British National Formulary. The objectives of this review were to identify clinical evidence for high-dose amikacin regimens and to determine drug exposures that are related to adverse events and toxicity.

METHODS

The literature search was conducted in October 2021 and updated in May 2022 using electronic databases for any study reporting adult participants treated with amikacin at doses ≥20 mg/kg/day. Reference lists of included papers were also screened for potential papers. Data were extracted for pharmacokinetic parameters and clinical outcomes, presented in a summary table and consolidated narratively. Meta-analysis was not possible. Each study was assessed for bias before, during and after the intervention using the ROBINS-I tool.

RESULTS

Nine studies (total 501 participants in 10 reports) were identified and included, eight of which were observational studies. Assessment of bias showed substantial flaws. Dosing regimens ranged from 25 to 30 mg/kg/day. Six studies adjusted the dose in obesity when participants had a body mass index of ≥30 kg/m2. Target peak serum concentrations ranged from 60 mg/L to 80 mg/L and 59.6-81.8% of patients achieved these targets, but there was no information on clinical outcomes. Two studies reported the impact of high-dose amikacin on renal function. No studies reporting auditory or vestibular toxicity were identified.

CONCLUSION

All included papers were limited by a significant risk of bias, while methodological and reporting heterogeneity made drawing conclusions challenging. Lack of information on the impact on renal function or ototoxicity means high-dose regimens should be used cautiously in older people. There is a need for a consensus guideline for high-dose amikacin to be written.

TRIAL REGISTRATION NUMBER

PROSPERO (CRD42021250022).

Antimicrobial Exposures in Critically Ill Patients Receiving Extracorporeal Membrane Oxygenation

Rationale: Data suggest that altered antimicrobial concentrations are likely during extracorporeal membrane oxygenation (ECMO). Objectives: The primary aim of this analysis was to describe the pharmacokinetics (PKs) of antimicrobials in critically ill adult patients receiving ECMO. Our secondary aim was to determine whether current antimicrobial dosing regimens achieve effective and safe exposure. Methods: This study was a prospective, open-labeled, PK study in six ICUs in Australia, New Zealand, South Korea, and Switzerland. Serial blood samples were collected over a single dosing interval during ECMO for 11 antimicrobials. PK parameters were estimated using noncompartmental methods. Adequacy of antimicrobial dosing regimens were evaluated using predefined concentration exposures associated with maximal clinical outcomes and minimal toxicity risks. Measurements and Main Results: We included 993 blood samples from 85 patients. The mean age was 44.7 ± 14.4 years, and 61.2% were male. Thirty-eight patients (44.7%) were receiving renal replacement therapy during the first PK sampling. Large variations (coefficient of variation of ⩾30%) in antimicrobial concentrations were seen leading to more than fivefold variations in all PK parameters across all study antimicrobials. Overall, 70 (56.5%) concentration profiles achieved the predefined target concentration and exposure range. Target attainment rates were not significantly different between modes of ECMO and renal replacement therapy. Poor target attainment was observed across the most frequently used antimicrobials for ECMO recipients, including for oseltamivir (33.3%), piperacillin (44.4%), and vancomycin (27.3%). Conclusions: Antimicrobial PKs were highly variable in critically ill patients receiving ECMO, leading to poor target attainment rates. Clinical trial registered with the Australian New Zealand Clinical Trials Registry (ACTRN12612000559819).

Pharmacokinetics/pharmacodynamics of ceftobiprole in patients on extracorporeal membrane oxygenation

INTRODUCTION

Due to its bacteriological spectrum and efficacy in skin and soft tissue infections, ceftobiprole may be of interest for extracorporeal membrane oxygenation (ECMO) cannula-related infection. It is unknown whether ceftobiprole pharmacokinetics (PK) are changed by ECMO.

METHODS

A retrospective monocentric cohort study was performed of 35 patients with suspected ECMO-related cannula infections (28 on ECMO, seven after ECMO removal), who received ceftobiprole as empiric treatment and had ceftobiprole blood levels measured at trough, peak and CT50 (50% of the dosing interval). Ceftobiprole blood levels of the 28 patients on ECMO were compared with those of the seven patients without ECMO. Factors associated with low ceftobiprole trough levels were also explored.

RESULTS

Among the 35 patients included, 29 had a confirmed cannula-related infection and 48 pathogens were isolated. Ceftobiprole MIC was determined in 29 of these 48, and 23 (79%) were susceptible to ceftobiprole. Ceftobiprole blood levels (at trough, peak and CT50) were similar in ECMO and non-ECMO patients. Moreover, in patients whose pathogens responsible for infection were susceptible to ceftobiprole, 94% had a ceftobiprole trough level above the MIC. Ceftobiprole blood levels were decreased in patients with acute renal failure requiring renal replacement therapy (RRT) and in those with increased renal clearance (defined as creatinine clearance > 130 mL/min), independent of ECMO. No other factor was associated with modification of ceftobiprole PK/pharmacodynamics (PK/PD).

CONCLUSIONS

The ceftobiprole PK/PD was no different in patients during ECMO or after its withdrawal. Factors associated with decreased ceftobiprole blood levels were patients requiring RRT and those with increased renal clearance.

A Narrative Review of the Impact of Extracorporeal Membrane Oxygenation on the Pharmacokinetics and Pharmacodynamics of Critical Care Therapies

Objective:

Extracorporeal membrane oxygenation (ECMO) utilization is increasing on a global scale, and despite technological advances, minimal standardized approaches to pharmacotherapeutic management exist. This objective was to create a comprehensive review for medication dosing in ECMO based on the most current evidence.

Data Sources:

A literature search of PubMed was performed for all pertinent articles prior to 2022. The following search terms were utilized: ECMO, pharmacokinetics, pharmacodynamics, sedation, analgesia, antiepileptic, anticoagulation, antimicrobial, antifungal, nutrition. Retrospective cohort studies, case-control studies, case series, case reports, and ex vivo investigations were reviewed.

Study Selection and Data Extraction:

PubMed (1975 through July 2022) was the database used in the literature search. Non-English studies were excluded. Search terms included both drug class categories, specific drug names, ECMO, and pharmacokinetics.

Data Synthesis:

Medications with high protein binding (>70%) and high lipophilicity (logP > 2) are associated with circuit sequestration and the potential need for dose adjustment. Volume of distribution changes with ECMO may also impact dosing requirements of common critical care medications. Lighter sedation targets and analgosedation may help reduce sedative and analgesia requirements, whereas higher antiepileptic dosing is recommended. Vancomycin is minimally affected by the ECMO circuit and recommendations for dosing in critically ill adults are reasonable. Anticoagulation remains challenging as optimal aPTT goals have not been established.

Relevance to Patient Care and Clinical Practice:

This review describes the anticipated impacts of ECMO circuitry on sedatives, analgesics, anticoagulation, antiepileptics, antimicrobials, antifungals, and nutrition support and provides recommendations for drug therapy management.

Conclusions:

Medication pharmacokinetic/pharmacodynamic parameters should be considered when determining the potential impact of the ECMO circuit on attainment of therapeutic effect and target serum drug concentrations, and should guide therapy choices and/or dose adjustments when data are not available.

Therapeutic Drug Monitoring of Antibiotic Drugs in Patients Receiving Continuous Renal Replacement Therapy or Intermittent Hemodialysis: A Critical Review

PURPOSE

Antibiotics are frequently used in patients receiving intermittent or continuous renal replacement therapy (RRT). Continuous renal replacement may alter the pharmacokinetics (PK) and the ability to achieve PK/pharmacodynamic (PD) targets. Therapeutic drug monitoring (TDM) could help evaluate drug exposure and guide antibiotic dosage adjustment. The present review describes recent TDM data on antibiotic exposure and PK/PD target attainment (TA) in patients receiving intermittent or continuous RRT, proposing practical guidelines for performing TDM.

METHODS

Studies on antibiotic TDM performed in patients receiving intermittent or continuous RRT published between 2000 and 2020 were searched and assessed. The authors focused on studies that reported data on PK/PD TA. TDM recommendations were based on clinically relevant PK/PD relationships and previously published guidelines.

RESULTS

In total, 2383 reports were retrieved. After excluding nonrelevant publications, 139 articles were selected. Overall, 107 studies reported PK/PD TA for 24 agents. Data were available for various intermittent and continuous RRT techniques. The study design, TDM practice, and definition of PK/PD targets were inconsistent across studies. Drug exposure and TA rates were highly variable. TDM seems to be necessary to control drug exposure in patients receiving intermittent and continuous RRT techniques, especially for antibiotics with narrow therapeutic margins and in critically ill patients. Practical recommendations can provide insights on relevant PK/PD targets, sampling, and timing of TDM for various antibiotic classes.

CONCLUSIONS

Highly variable antibiotic exposure and TA have been reported in patients receiving intermittent or continuous RRT. TDM for aminoglycosides, beta-lactams, glycopeptides, linezolid, and colistin is recommended in patients receiving RRT and suggested for daptomycin, fluoroquinolones, and tigecycline in critically ill patients on RRT.

Population Pharmacokinetics of Amikacin in Patients on Veno-Arterial Extracorporeal Membrane Oxygenation

Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) support leads to complex pharmacokinetic alterations, whereas adequate drug dosing is paramount for efficacy and absence of toxicity in critically ill patients. Amikacin is a major antibiotic used in nosocomial sepsis, especially for these patients. We aimed to describe amikacin pharmacokinetics on V-A ECMO support and to determine relevant variables to improve its dosing. All critically ill patients requiring empirical antimicrobial therapy, including amikacin for nosocomial sepsis supported or not by V-A ECMO, were included in a prospective population pharmacokinetic study. This population pharmacokinetic analysis was built with a dedicated software, and Monte Carlo simulations were performed to identify doses achieving therapeutic plasma concentrations. Thirty-nine patients were included (control n = 15, V-A ECMO n = 24); 215 plasma assays were performed and used for the modeling process. Patients received 29 (24–33) and 32 (30–35) mg/kg of amikacin in control and ECMO groups, respectively. Data were best described by a two-compartment model with first-order elimination. Inter-individual variabilities were observed on clearance, central compartment volume (V₁)_, and peripherical compartment volume (V₂). Three significant covariates explained these variabilities: Kidney Disease Improving Global Outcomes (KDIGO) stage on amikacin clearance, total body weight on V_1, and ECMO support on V₂. Our simulations showed that the adequate dosage of amikacin was 40 mg/kg in KDIGO stage 0 patients, while 25 mg/kg in KDIGO stage 3 patients was relevant. V-A ECMO support had only a secondary impact on amikacin pharmacokinetics, as compared to acute kidney injury.

Machines that help machines to help patients: optimising antimicrobial dosing in patients receiving extracorporeal membrane oxygenation and renal replacement therapy using dosing software

Intensive care unit (ICU) patients with end-organ failure will require specialised machines or extracorporeal therapies to support the failing organs that would otherwise lead to death. ICU patients with severe acute kidney injury may require renal replacement therapy (RRT) to remove fluid and wastes from the body, and patients with severe cardiorespiratory failure will require extracorporeal membrane oxygenation (ECMO) to maintain adequate oxygen delivery whilst the underlying pathology is evaluated and managed. The presence of ECMO and RRT machines can further augment the existing pharmacokinetic (PK) alterations during critical illness. Significant changes in the apparent volume of distribution (V_d) and drug clearance (CL) for many important drugs have been reported during ECMO and RRT. Conventional antimicrobial dosing regimens rarely consider the impact of these changes and consequently, are unlikely to achieve effective antimicrobial exposures in critically ill patients receiving ECMO and/or RRT. Therefore, an in-depth understanding on potential PK changes during ECMO and/or RRT is required to inform antimicrobial dosing strategies in patients receiving ECMO and/or RRT. In this narrative review, we aim to discuss the potential impact of ECMO and RRT on the PK of antimicrobials and antimicrobial dosing requirements whilst receiving these extracorporeal therapies. The potential benefits of therapeutic drug monitoring (TDM) and dosing software to facilitate antimicrobial therapy for critically ill patients receiving ECMO and/or RRT are also reviewed and highlighted.

Pharmacokinetics of Commonly Used Antimicrobials in Critically Ill Adults During Extracorporeal Membrane Oxygenation: A Systematic Review

PURPOSE

Adequate dosing of antimicrobials is critical to properly treat infections and limit development of resistance and adverse effects. Limited guidance exists for antimicrobial dosing adjustments in patients requiring extracorporporeal membrane oxygenation (ECMO) therapy. A systematic review was conducted to delineate the pharmacokinetics (PK) and pharmacodynamics (PD) of antimicrobials in critically ill adult patients requiring ECMO.

METHODS

Medline, EMBASE, Global Health, and All EBM Reviews databases were searched. Grey literature was examined. All studies reporting PK/PD parameters of antimicrobials in critically ill adults treated with ECMO were included, except for case reports and congress abstracts. Ex vivo studies were included. Two independent reviewers applied the inclusion and exclusion criteria. Reviewers were then paired to independently abstract data and evaluate methodological quality of studies using the ROBINS-I tool and the compliance with ClinPK guidelines. Patients' and studies' characteristics, key PK/PD findings, details of ECMO circuits and co-treatments were summarized qualitatively. Dosing recommendations were formulated based on data from controlled studies.

RESULTS

Thirty-two clinical studies were included; most were observational and uncontrolled. Fourteen ex vivo studies were analysed. Information on patient characteristics and co-treatments was often missing. The effect of ECMO on PK/PD parameters of antimicrobials varied depending on the studied drugs. Few dosing recommendations could be formulated given the lack of good quality data.

CONCLUSION

Limited data exist on the PK/PD of antimicrobials during ECMO therapy. Rigorously designed and well powered populational PK studies are required to establish empiric dosing guidelines for antimicrobials in patients requiring ECMO support.

PROSPERO REGISTRATION NUMBER

CRD42018099992 (Registered: July 24th 2018).

In vitro activity of ceftolozane/tazobactam alone and in combination with amikacin against MDR/XDR Pseudomonas aeruginosa isolates from Greece

OBJECTIVES

We evaluated the in vitro activity of ceftolozane/tazobactam and comparator agents against MDR non-MBL Pseudomonas aeruginosa isolates collected from nine Greek hospitals and we assessed the potential synergistic interaction between ceftolozane/tazobactam and amikacin.

METHODS

A total of 160 non-MBL P. aeruginosa isolates collected in 2016 were tested for susceptibility to ceftolozane/tazobactam and seven comparator agents including ceftazidime/avibactam. Time-kill assays were performed for synergy testing using ceftolozane/tazobactam 60 or 7.5 mg/L, corresponding to the peak and trough concentrations of a 1.5 g q8h dose, respectively, in combination with 69 mg/L amikacin, corresponding to the free peak plasma concentration. Synergy was defined as a ≥2 log10 cfu/mL reduction compared with the most active agent.

RESULTS

Overall, ceftolozane/tazobactam inhibited 64.4% of the P. aeruginosa strains at ≤4 mg/L. Colistin was the most active agent (MIC50/90, 0.5/2 mg/L; 96.3% susceptible) followed by ceftazidime/avibactam (MIC50/90, 4/16 mg/L; 80.6% susceptible). GES-type enzymes were predominantly responsible for ceftolozane/tazobactam resistance; 81.6% of the non-producers were susceptible. MICs for the P. aeruginosa isolates selected for synergy testing were 2-32 mg/L ceftolozane/tazobactam and 2-128 mg/L amikacin. The combination of ceftolozane/tazobactam with amikacin was synergistic against 85.0% of all the isolates tested and against 75.0% of the GES producers. No antagonistic interactions were observed.

CONCLUSIONS

Ceftolozane/tazobactam demonstrated good in vitro activity against MDR/XDR P. aeruginosa clinical isolates, including strains with co-resistance to other antipseudomonal drugs. In combination with amikacin, a synergistic interaction at 24 h was observed against 85.0% of P. aeruginosa strains tested, including isolates with ceftolozane/tazobactam MICs of 32 mg/L or GES producers.

Evaluation of Current Amikacin Dosing Recommendations and Development of an Interactive Nomogram: The Role of Albumin

This study aimed to evaluate the potential efficacy and safety of the amikacin dosage proposed by the main guidelines and to develop an interactive nomogram, especially focused on the potential impact of albumin on initial dosage recommendation. The probability of target attainment (PTA) for each of the different dosing recommendations was calculated through stochastic simulations based on pharmacokinetic/pharmacodynamic (PKPD) criteria. Large efficacy and safety differences were observed for the evaluated amikacin dosing guidelines together with a significant impact of albumin concentrations on efficacy and safety. For all recommended dosages evaluated, efficacy and safety criteria of amikacin dosage proposed were not achieved simultaneously in most of the clinical scenarios evaluated. Furthermore, a significant impact of albumin was identified: The higher is the albumin, (i) the higher will be the PTA for maximum concentration/minimum inhibitory concentration (Cmax/MIC), (ii) the lower will be the PTA for the time period with drug concentration exceeding MIC (T_>MIC) and (iii) the lower will be the PTA for toxicity (minimum concentration). Thus, accounting for albumin effect might be of interest for future amikacin dosing guidelines updates. In addition, AMKnom, an amikacin nomogram builder based on PKPD criteria, has been developed and is freely available to help evaluating dosing recommendations.

Antibiotic dosing during extracorporeal membrane oxygenation: does the system matter?

PURPOSE OF REVIEW

The aims of this review are to discuss the impact of extracorporeal membrane oxygenation (ECMO) on antibiotic pharmacokinetics and how this phenomenon may influence antibiotic dosing requirements in critically ill adult ECMO patients.

RECENT FINDINGS

The body of literature describing antibiotic pharmacokinetic and dosing requirements during ECMO support in critically adult patients is currently scarce. However, significant development has recently been made in this research area and more clinical pharmacokinetic data have emerged to inform antibiotic dosing in these patients. Essentially, these clinical data highlight several important points that clinicians need to consider when dosing antibiotics in critically ill adult patients receiving ECMO: physicochemical properties of antibiotics can influence the degree of drug loss/sequestration in the ECMO circuit; earlier pharmacokinetic data, which were largely derived from the neonatal and paediatric population, are certainly useful but cannot be extrapolated to the critically ill adult population; modern ECMO circuitry has minimal adsorption and impact on the pharmacokinetics of most antibiotics; and pharmacokinetic changes in ECMO patients are more reflective of critical illness rather than the ECMO therapy itself.

SUMMARY

An advanced understanding of the pharmacokinetic alterations in critically ill patients receiving ECMO is essential to provide optimal antibiotic dosing in these complex patients pending robust dosing guidelines. Antibiotic dosing in this patient population should generally align with the recommended dosing strategies for critically ill patients not on ECMO support. Performing therapeutic drug monitoring (TDM) to guide antibiotic dosing in this patient population appears useful.

[Clinical pharmacokinetics of anti-infective drugs in extracorporeal membrane oxygenation]

Extracorporeal membrane oxygenation (ECMO) is becoming more and more clinically important. The extracorporeal circuit for membrane oxygenation consists of a pump, a membrane oxygenator and large volume tubing. The ECMO device forms an additional compartment, which can absorb drugs with high lipophilia and protein binding. Thus, ECMO affects the volume of distribution and the clearance. As a consequence, the pharmacokinetic-pharmacodynamic (pk-pd) target parameters cannot be achieved. The selection of an appropriate substance and the mode of application, combined with therapeutic drug monitoring (TDM), can significantly improve the therapeutic outcome of critically ill patients.

PHARMECMO: Therapeutic drug monitoring and adequacy of current dosing regimens of antibiotics in patients on Extracorporeal Life Support

INTRODUCTION

Optimisation of antibiotic therapy for extracorporeal membrane oxygenation (ECMO) patients remains a pharmacological challenge. The objective of this study was to observe the plasma concentrations of commonly used antibiotics in intensive care for patients treated with extracorporeal membrane oxygenation.

PATIENTS AND METHODS

The PHARMECMO study was a pilot, prospective study, conducted in a cardiac surgery intensive care unit. Every adult patient under ECMO support, with known or suspected sepsis and receiving antibiotic therapy, was eligible for inclusion. Plasma concentrations of antibiotics were determined by a combination of liquid chromatography and mass spectrometry.

RESULTS

Forty-four eligible patients were enrolled for 68 inclusions on a twelve-month period. For the association piperacillin-tazobactam (n=19), 68.7% of CT50 and 93.7% of Cmin reached the pharmacokinetic goals defined (64 mg.L-1 for CT50 and 16 mg.L-1 for Cmin). For cefotaxime (n=12), the pharmacokinetic goals (4 mg.L-1 for CT50 and 1 mg.L-1 for Cmin) were achieved in 100% of the cases for CT50 and in 81.8% of the cases for Cmin. Regarding imipenem (n=10), the pharmacokinetic goals were 16 mg.L-1 for CT50 and 4 mg.L-1 for Cmin. Only one CT50 was above 16 mg.L-1. For Cmin, 60% of the doses did not reach the target concentration. In our 10 patients, only one patient was considered as reaching the pharmacokinetic goals. Finally, for amikacin (n=6), four Cmax (66.7%) were infra-therapeutics for a target between 60 and 80 mg.L-1.

CONCLUSION

These preliminary results suggest that therapeutic drug monitoring could optimise the achievement of pharmacokinetic objectives associated with an effective antibiotic therapy. For most patients, the recommended doses of imipenem and amikacin did not achieve the pK targets.

Ventilator-associated pneumonia in extracorporeal membrane oxygenation-assisted patients

Extracorporeal membrane oxygenation (ECMO) provides a circulatory and/or respiratory assistance in case of refractory cardiogenic shock or acute respiratory distress syndrome (ARDS). Due to their extreme critical illness, these patients usually require prolonged mechanical ventilation, which is an inherent risk of ventilator-associated pneumonia (VAP). Although microorganisms responsible of VAP on ECMO are similar to those found in non-ECMO patients, classical suspicion criteria of VAP are no longer relevant on ECMO. Frequent severe chest X-Ray impairments, and poor specificity of the classical biomarkers on ECMO make VAP diagnosis challenging. In addition, significant drug pharmacokinetic modifications by the device may lead to low plasmatic antibiotic concentration and potential treatment failure. Consequently, rate of treatment failure and relapse appear high in that population (up to 30%), with significant impact on mortality and on the ECMO duration.