Nosocomial infections in adult cardiogenic shock patients supported by venoarterial extracorporeal membrane oxygenation

Which antimicrobial treatment for patients with bloodstream infection during ECMO support?

OJECTIVE

We aim to describe a large, multicenter cohort of patients with bloodstream infection (BSI) acquired during extracorporeal membrane oxygenation (ECMO) support.

METHODS

We conducted a retrospective observational study in 12 Europeans ICUs. Only patients who developed a BSI of unknown source during ECMO support were included in the present analysis. Primary aim was to describe BSI epidemiology in patients with ECMO support. Secondary objectives were to describe antimicrobial susceptibility of incriminated micro-organisms.

RESULTS

One hundred and eighty-two patients were included. Main reason for ECMO support was ARDS, followed by cardiogenic shock and post-cardiotomy. Half of the patients (51.9%) received early antimicrobial therapy. Main incriminated microorganisms were Enterococcus sp. (37.4%), Enterobacterales (26.9%), coagulase negative Staphylococci (15.9%) and Gram negative bacilli (11.5%). Multi drug resistant organisms (MDRO) were incriminated in 26 (14.3%) BSI and were mainly extended spectrum producing-Enterobacterales (17/26). Antimicrobial therapy was considered as appropriate in 130 patients (71.4%). Patients who received inappropriate antimicrobial therapy were more frequently infected with MDRO. Only 59 (32.4%) of cases were susceptible to 3rd generation cephalosporin while association of piperacillin/tazobactam with vancomycin was considered appropriate in 155 cases (85.2%) as compared with 168 cases (92.3%) for carbapenems combined with vancomycin.

CONCLUSION

Enterococcus sp. was incriminated in about a third of BSI among patients with ECMO support. High appropriateness would only be obtained with piperacilline/tazobactam or carbapenems in association with vancomycin while 3rd generation cephalosporin would have failed in the majority of BSI cases.

CLINICAL TRIAL NUMBER

Not applicable.

Infected Thrombosis Leading to Veno-Venous Extracorporeal Membrane Oxygenation Dysfunction in Chronic Thromboembolic Pulmonary Hypertension

Nosocomial infections and thrombosis are frequent complications during extracorporeal membrane oxygenation (ECMO). Preventative measures and close monitoring for early recognition of these complications are imperative in patients supported with ECMO. We report the case of a 41 year old female on veno-venous ECMO awaiting surgical thrombectomy for chronic thromboembolic pulmonary hypertension that developed profound bacteremia leading to gross purulence and thrombosis of the membrane oxygenator. Recannulation in addition to targeted antibiotics, frequent cultures, imaging, and surgery were diagnostic and therapeutic interventions that led to ultimate resolution.

Clinical Characteristics of Fever After Extracorporeal Membrane Oxygenation Decannulation: Differentiating Infectious from Non-Infectious Causes of Fever and Their Impact on Outcomes

Background: A fever is an important sign that affects patient outcomes with various etiologies in the post-decannulation period of extracorporeal membrane oxygenation (ECMO); however, the cause is not fully understood. This study aimed to investigate the characteristics and clinical implications of fevers after ECMO decannulation in critically ill patients. Methods: We conducted a retrospective, single-center study of adult patients who were successfully weaned off venoarterial (VA) or venovenous (VV) ECMO. Decannulation fever was defined as fever that occurred within 72 h of ECMO decannulation. The peak and duration of fever were followed for 2 weeks after decannulation, and the relationship with infection was assessed. Results: A total of 47 patients were included (22 [46.8%] on VA ECMO and 25 [53.2%] on VV ECMO). There were 35 (74.5%) patients who had decannulation fever, including 16 (34%) with active infections. Active infection during the study period was not related to the ECMO setting or duration; rather, infectious fever lasted longer than non-infectious fever (4 [interquartile range; IQR: 1-7] vs. 11 [IQR: 2-7] days, p = 0.023), and the C-reactive protein level was higher on post-decannulation day 7 (p = 0.006). Active infection was associated with increased mortality (odds ratio [OR] 6.067, 95% confidence interval [CI] 1.1289-32.644, p = 0.036), whereas decannulation fever was not (OR 0.156, 95% CI 0.025-0.977, p = 0.047). Conclusions: Fever is an important indicator of ECMO decannulation. However, the different timing and duration of fevers during the post-decannulation period of ECMO may have various clinical implications.

Analysis of diagnostic criteria for ECMO-associated pneumonia

Ventilator-associated pneumonia (VAP) is a well-established cause of morbidity in critically ill patients. Current VAP criteria exclude patients on extracorporeal membrane oxygenation (ECMO). This retrospective analysis tests the validity of VAP in this population, as well as a new proposed diagnostic criterion for ECMO-associated pneumonia.

Infections in Patients with Mechanical Circulatory Support

Patients on mechanical circulatory support are at heightened risk for infection given the invasive nature of the devices with internal and external components, the surgical implantation of the devices, and the presence of foreign material susceptible to biofilm formation. This review discusses the new International Society for Heart and Lung Transplantation mechanical circulatory support device infection definitions, inclusive of durable and acute mechanical circulatory support infections, and describes their epidemiology, diagnosis, and management. A multidisciplinary approach is essential for optimal management. Timing of transplantation in the context of active infection is addressed, and areas of future research are highlighted.

Prone position in obese patients with acute respiratory distress syndrome after cardio-thoracic surgery

OBJECTIVES

Prone positioning (PP) has benefits in patients with acute respiratory distress syndrome. The objective of this study was to compare the effects and complications of PP in obese versus non-obese patients with moderate-to-severe acute respiratory distress syndrome after cardiothoracic surgery.

METHODS

We retrospectively analysed a database established in 2014-2021 in an intensive care unit. The primary end point was the change in PaO2/FiO2 induced by PP. Secondary end points included pressure ulcers, mediastinitis and intensive care unit mortality. The groups with versus without obesity (body mass index >30 kg/m2) were compared, and a mixed linear model was built to identify factors associated with the PaO2/FiO2 change.

RESULTS

81 patients with acute respiratory distress syndrome (36 with vs 45 without obesity) and 189 PP sessions were included. PP duration was 17.2 ± 4.5 h in obese and 18.0 ± 3.8 h in non-obese patients (P = 0.23). Mean number of sessions was 2.6 ± 1.4 in obese and 2.1 ± 1.3 in non-obese patients (P = 0.10). Median PaO2/FiO2 increase after the 1st PP session was 75.0% [14.5-123.0] and 72% [15.5-130.5] in the groups with versus without obesity (P = 0.67). Stage 3/4 pressure ulcers were more common in the obese group (44.4% vs 22.2%; P = 0.03) and occurred chiefly on the face. No significant differences between the obese and non-obese groups were found for mediastinitis (16.7% vs 8.9%, P = 0.33) or intensive care unit mortality (22% vs 20%, P = 0.81).

CONCLUSIONS

Improvement of oxygenation was not statistically different between patients with versus without obesity. Pressure ulcers were more common in the obese group, whereas mediastinitis was not. No patient experienced wound dehiscence.

Risk factors for nosocomial infection in patients undergoing extracorporeal membrane oxygenation support treatment: A systematic review and meta-analysis

OBJECTIVE

To evaluate the risk factors of nosocomial infection during Extracorporeal membrane oxygenation (ECMO) treatment through systematic evaluation and meta-analysis, in order to provide evidence-based basis for clinical treatment and prevention of nosocomial infection during ECMO treatment.

METHOD

Computer search of Cochrane Library, PubMed, Embase, and Web of Science databases was conducted to establish a database of relevant literature published in March 2023. Two researchers independently screened literature, extracted data, and evaluated quality based on inclusion and exclusion criteria, and then analyzed the data using STATA 14.0 software. This plan is registered with PROSPERO as CRD42021271083.

RESULT

A total of 2955 ECMO patients, including 933 nosocomial infected patients, were included in 23 articles. Meta analysis showed that immunosuppression, Heart transplantation, VA-ECMO, CRRT, red blood cell input, ECMO support time, mechanical ventilation time, ICU hospitalization time, and total hospitalization time were the risk factors for nosocomial infection in patients supported by ECMO.

CONCLUSION

ECMO treatment for nosocomial infections in patients is related to multiple factors. In clinical work, medical staff should identify high-risk groups of ECMO nosocomial infections, actively take preventive measures, and reduce the incidence and mortality of nosocomial infections.

Do patients receiving extracorporeal membrane-oxygenation need antibiotic prophylaxis? A systematic review and meta-analysis on 7,996 patients

BACKGROUND

Patients undergoing Extracorporeal Membrane Oxygenation (ECMO) are particularly susceptible to infections: 42% experience sepsis and 26% develop a nosocomial infection (NI). Whether antibiotic prophylaxis is effective in reducing mortality and its effects on the rate of NIs is currently unclear.

RESEARCH QUESTION

Can antibiotic prophylaxis decrease 30-day mortality for patients on ECMO? Can antibiotic prophylaxis prevent the occurrence of NIs in these patients?

STUDY DESIGN AND METHODS

A systematic review and meta-analysis was conducted. We searched PubMed, Scopus, and CINAHL libraries from inception to June 12, 2024. Two researchers were involved in abstract screening and three researchers were involved in full text selection.

RESULTS

A pooled population of 7,996 patients is represented by 5 retrospective studies. Reported mortality ranges between 46 and 58% and the NIs rate is between 14 and 62%. Regarding 30-day mortality, the random-effects model (I2 = 65%) indicates a non-statistically significant difference between the antibiotic prophylaxis group and the non-prophylaxis group (OR 0.76; 95%CI 0.37-1.59). For the NIs rate, a fixed-effect model (I2 = 36%) shows an OR of 0.81 (95%CI 0.71-0.92) in favor of the antibiotic prophylaxis group, with a number-needed-to-treat (NNT) of 39.7 patients.

CONCLUSION

According to a very low degree of certainty, antibiotic prophylaxis appears to have no impact on the 30-day mortality rate of ECMO recipients. The risk of NIs seems to decrease with antibiotic prophylaxis, even though the NNT is high. Prospective high-quality studies that address these specific clinical questions are necessary.

CLINICAL TRIAL REGISTRATION

PROSPERO: International prospective register of systematic reviews, 2024, CRD42024567037.

Early mNGS testing for diagnose and prognostic prediction of early onset pneumonia among in-hospital cardiac arrest patients undergoing extracorporeal cardiopulmonary resuscitation

Objectives

Metagenomic next-generation sequencing (mNGS) is emerging as a novel diagnostic technology for various infectious diseases; however, limited studies have investigated its application in etiological diagnosis of early onset pneumonia (EOP) among patients undergoing extracorporeal cardiopulmonary resuscitation (ECPR) following in-hospital cardiac arrest (IHCA), The clinical significance of early mNGS in predicting short-term prognosis of IHCA patients after ECPR remains unclear.

Methods

This retrospective study included 76 patients with IHCA who underwent ECPR at the First Affiliated Hospital of Zhengzhou University from January 2018 to December 2022. Baseline characteristics and etiological data of all patients during their hospitalization were collected and statistically analyzed. The primary outcome of this study was the diagnosis of EOP, while the secondary outcomes included successful extracorporeal membrane oxygenation (ECMO) weaning and survival at discharge. Additionally, the characteristics of bronchoalveolar lavage fluid (BALF) flora in these patients were compared by analyzing both mNGS results and culture results.

Results

Multivariate logistic regression were employed to analyze the predictors of ECMO weaning failure, mortality at discharge, and the incidence of EOP. Ultimately, patients with lower SOFA scores on admission [OR (95%CI): 1.447 (1.107-1.890), p=0.007] and those who underwent early mNGS testing within 48 hours after ECPR [OR (95%CI): 0.273 (0.086-0.865), p=0.027] demonstrated a higher probability of successful weaning from ECMO. Patients with higher SOFA scores on admission [OR (95%CI): 2.404 (1.422-4.064), p=0.001], and elevated lactate levels [OR (95%CI): 1.176 (1.017-1.361), p=0.029] exhibited an increased likelihood of mortality at discharge. Furthermore, early mNGS detection [OR (95%CI): 0.186 (0.035-0.979), p=0.047], and lower CRP levels (48h-7d after ECMO) [OR (95%CI):1.011 (1.003-1.019), p=0.006] were associated with a reduced incidence of EOP. In addition, the pathogens detected by mNGS within 48 hours after ECPR were mainly oral colonizing bacteria and viruses, and viruses were in the majority, while all BALF cultures were negative. In contrast, between 48 hours and 7 days after ECPR, BALF cultures were positive in all EOP patients.

Conclusions

Early mNGS testing to identify microbial flora facilitates timely adjustment of antibiotic regimens, thereby reducing the incidence of EOP and improving short-term prognosis in patients undergoing ECPR following IHCA.

The impact of door to extracorporeal cardiopulmonary resuscitation time on mortality and neurological outcomes among out-of-hospital cardiac arrest acute myocardial infarction patients treated by primary percutaneous coronary intervention

Background

Few previous studies evaluated the impact of time from the hospital arrival to the implementation of extracorporeal cardiopulmonary resuscitation (ECPR) (door to ECPR time) on outcomes among out-of-hospital cardiac arrest (OHCA) acute myocardial infarction (MI) patients.

Methods

50 patients with OHCA who received both ECPR and percutaneous coronary intervention (PCI) at Cardiovascular Division, NHO Osaka National Hospital were analyzed. Patients were divided into 2 groups according to the median of door to ECPR time. The primary outcome was all-cause death. Survival analyses were conducted to compare all-cause mortality at 90 days between 2 groups. Neurological outcome at 30 days was also compared between 2 groups using the Cerebral Performance Category (CPC).

Results

The multivariable Cox proportional-hazards model showed that all-cause mortality at 90 days was significantly higher among patients with door to ECPR time ≥ 25 min compared with those with door to ECPR time < 25 min (adjusted hazard ratio [HR]: 3.14; 95 % confidence interval [CI]: 1.21-8.18). The proportion of patients with CPC at 30 days ≤ 2 was significantly higher among patients with shorter door to ECPR time (P = 0.048).

Conclusion

Among patients with OHCA due to acute MI who received ECPR and PCI, the shorter door to ECPR time was associated with the lower mortality and favorable neurological outcomes.

Characteristics and Outcomes of Prolonged Venoarterial Extracorporeal Membrane Oxygenation After Cardiac Surgery: The Post-Cardiotomy Extracorporeal Life Support (PELS-1) Cohort Study

OBJECTIVES

Most post-cardiotomy (PC) extracorporeal membrane oxygenation (ECMO) runs last less than 7 days. Studies on the outcomes of longer runs have provided conflicting results. This study investigates patient characteristics and short- and long-term outcomes in relation to PC ECMO duration, with a focus on prolonged (> 7 d) ECMO.

DESIGN

Retrospective observational cohort study.

SETTING

Thirty-four centers from 16 countries between January 2000 and December 2020.

PATIENTS

Adults requiring post PC ECMO between 2000 and 2020.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Characteristics, in-hospital, and post-discharge outcomes were compared among patients categorized by ECMO duration. Survivors and nonsurvivors were compared in the subgroup of patients with ECMO duration greater than 7 days. The primary outcome was in-hospital mortality. Two thousand twenty-one patients were included who required PC ECMO for 0-3 days ( n = 649 [32.1%]), 4-7 days ( n = 776 [38.3%]), 8-10 days ( n = 263 [13.0%]), and greater than 10 days ( n = 333 [16.5%]). There were no major differences in the investigated preoperative and procedural characteristics among ECMO duration groups. However, the longer ECMO duration category was associated with multiple complications including bleeding, acute kidney injury, arrhythmias, and sepsis. Hospital mortality followed a U-shape curve, with lowest mortality in patients with ECMO duration of 4-7 days ( n = 394, 50.8%) and highest in patients with greater than 10 days ECMO support ( n = 242, 72.7%). There was no significant difference in post-discharge survival between ECMO duration groups. In patients with ECMO duration greater than 7 days, age, comorbidities, valvular diseases, and complex procedures were associated with nonsurvival.

CONCLUSIONS

Nearly 30% of PC ECMO patients were supported for greater than 7 days. In-hospital mortality increased after 7 days of support, especially in patients undergoing valvular and complex surgery, or who had complications, although the long-term post-discharge prognosis was comparable to PC ECMO patients with shorter support duration.

Frequency, characteristics, and outcome of adult patients with multiple consecutive health care-associated infections undergoing extracorporeal membrane oxygenation: A retrospective analysis

BACKGROUND

Data on multiple consecutive health care-associated infections (HAIs) in patients undergoing extracorporeal membrane oxygenation (ECMO) are limited. We aim to identify the characteristics and outcomes of multiple, consecutive HAIs.

METHODS

This retrospective study included adult patients who underwent ECMO in a single cardiac ICU in China from May 2015 to December 2022. The incidence, clinical characteristics, risk factors, and impact on in-hospital mortality among patients with non-HAI, single HAI, and multiple HAIs were analyzed. Pathogens and infection sites for each new episode were compared.

RESULTS

Of 192 patients, 92 (47.92%) developed 141 separate infections, with 41 (21.35%) experiencing multiple infections during a single ECMO period. Respiratory tract infections (RTIs) constituted the majority (75.89%), and gram-negative bacteria were the predominant pathogens (71.63%). RTIs decreased from 86.9% in the first infection to 14.3% in the third (P < .001), while bloodstream infections increased from 10.9 % to 57.1% (P < .001). The proportion of gram-positive bacteria increased from 9.8% to 42.9% (P = .032). Prolonged ECMO duration was the only independent risk factor for multiple consecutive HAIs (odds ratio (OR)=1.220, P < .001).

CONCLUSIONS

Multiple consecutive HAIs during ECMO were frequent, with distinct microbiological changes between initial and subsequent HAIs.

Incidence of nosocomial infection and causative microorganism during extracorporeal membrane oxygenation in adult patients, a single center study

INTRODUCTION

Extracorporeal membrane oxygenation (ECMO) is an organ support whose use is increasing in acute respiratory distress syndrome (ARDS) cases where adequate gas exchange cannot be achieved despite mechanical ventilation. Patients who were followed up on ECMO are at risk for developing nosocomial infections. In this study, we aimed to investigate the incidence of nosocomial infection and define isolated pathogens from microbiological samples in a single center in Turkey.

METHODS

Patients who were followed up on ECMO due to ARDS between January 1, 2018, and December 31, 2021, were included in the study. Nosocomial infections that were diagnosed after the first 48 h of ECMO cannulation and after 48 h of ECMO decannulation were accepted as ECMO-related infections.

RESULTS

A total of 50 patients with ARDS were followed up with ECMO. Mean age of patients was 46,8 ± 15,4 and 38 (78%) patients were male. A total of 30 patients (60%) had at least one nosocomial infection, for a rate of 37.6 per 1000 ECMO days. COVID-19, steroid treatment, and ECMO duration were found to be associated with nosocomial infections in patients who underwent ECMO support. In multivariate analysis, antibiotic use was found to be protective against nosocomial infection (OR:0.14, 95% CI: 0.03 - 0.70, p = .017). In addition, prolonged ECMO duration was associated with an increased risk of nosocomial infection in multivariate analysis (OR:1.13, 95% CI: 1.03 - 1.23, p = .010). Gram-negative pathogens were isolated dominantly in blood cultures and tracheal secretion samples, followed by fungi and Gram-positive bacteria.

CONCLUSION

Patients are prone to nosocomial infections during ECMO. Microorganisms causing nosocomial infections in ECMO patients seem similar to the flora of each center, and this should be taken into account in the choice of empirical antibiotics.

Cardiopulmonary bypass and VA-ECMO induced immune dysfunction: common features and differences, a narrative review

Cardiopulmonary bypass (CPB) and veno-arterial extracorporeal membrane oxygenation are critical tools in contemporary cardiac surgery and intensive care, respectively. While these techniques share similar components, their application contexts differ, leading to distinct immune dysfunctions which could explain the higher incidence of nosocomial infections among ECMO patients compared to those undergoing CPB. This review explores the immune modifications induced by these techniques, comparing their similarities and differences, and discussing potential treatments to restore immune function and prevent infections. The immune response to CPB and ECMO involves both humoral and cellular components. The kinin system, complement system, and coagulation cascade are rapidly activated upon blood contact with the circuit surfaces, leading to the release of pro-inflammatory mediators. Ischemia-reperfusion injury and the release of damage-associated molecular patterns further exacerbate the inflammatory response. Cellular responses involve platelets, neutrophils, monocytes, dendritic cells, B and T lymphocytes, and myeloid-derived suppressor cells, all of which undergo phenotypic and functional alterations, contributing to immunoparesis. Strategies to mitigate immune dysfunctions include reducing the inflammatory response during CPB/ECMO and enhancing immune functions. Approaches such as off-pump surgery, corticosteroids, complement inhibitors, leukocyte-depleting filters, and mechanical ventilation during CPB have shown varying degrees of success in clinical trials. Immunonutrition, particularly arginine supplementation, has also been explored with mixed results. These strategies aim to balance the inflammatory response and support immune function, potentially reducing infection rates and improving outcomes. In conclusion, both CPB and ECMO trigger significant immune alterations that increase susceptibility to nosocomial infections. Addressing these immune dysfunctions through targeted interventions is essential to improving patient outcomes in cardiac surgery and critical care settings. Future research should focus on refining these strategies and developing new approaches to better manage the immune response in patients undergoing CPB and ECMO.

Retrospective ANalysis of multi-drug resistant Gram-nEgative bacteRia on veno-venous extracorporeal membrane oxygenation. The multicenter RANGER STUDY

BACKGROUND

Veno-venous extracorporeal membrane oxygenation (V-V ECMO) is a rapidly expanding life-support technique worldwide. The most common indications are severe hypoxemia and/or hypercapnia, unresponsive to conventional treatments, primarily in cases of acute respiratory distress syndrome. Concerning potential contraindications, there is no mention of microbiological history, especially related to multi-drug resistant (MDR) bacteria isolated before V-V ECMO placement. Our study aims to investigate: (i) the prevalence and incidence of MDR Gram-negative (GN) bacteria in a cohort of V-V ECMOs; (ii) the risk of 1-year mortality, especially in the case of predetected MDR GN bacteria; and (iii) the impact of annual hospital V-V ECMO volume on the probability of acquiring MDR GN bacteria.

METHODS

All consecutive adults admitted to the Intensive Care Units of 5 Italian university-affiliated hospitals and requiring V-V ECMO were screened. Exclusion criteria were age < 18 years, pregnancy, veno-arterial or mixed ECMO-configuration, incomplete records, survival < 24 h after V-V ECMO. A standard protocol of microbiological surveillance was applied and MDR profiles were identified using in vitro susceptibility tests. Cox-proportional hazards models were applied for investigating mortality.

RESULTS

Two hundred and seventy-nine V-V ECMO patients (72% male) were enrolled. The overall MDR GN bacteria percentage was 50%: 21% (n.59) detected before and 29% (n.80) after V-V ECMO placement. The overall 1-year mortality was 42%, with a higher risk observed in predetected patients (aHR 2.14 [1.33-3.47], p value 0.002), while not in 'V-V ECMO-acquired MDR GN bacteria' group (aHR 1.51 [0.94-2.42], p value 0.090), as compared to 'non-MDR GN bacteria' group (reference). Same findings were found considering only infections. A larger annual hospital V-V ECMO volume was associated with a lower probability of acquiring MDR GN bacteria during V-V ECMO course (aOR 0.91 [0.86-0.97], p value 0.002).

CONCLUSIONS

21% of MDR GN bacteria were detected before; while 29% after V-V ECMO connection. A history of MDR GN bacteria, isolated before V-V ECMO, was an independent risk factor for mortality. The annual hospital V-V ECMO volume affected the probability of acquiring MDR GN bacteria. Trial Registration ClinicalTrial.gov Registration Number NCTNCT06199141, date 12.26.2023.

Nosocomial Infections in Adults Receiving Extracorporeal Membrane Oxygenation: A Review for Infectious Diseases Clinicians

Over the past 10 years, there has been a rapid expansion in the use of extracorporeal membrane oxygenation (ECMO) in the care of patients with refractory cardiac or respiratory failure. Infectious diseases clinicians must reconcile conflicting evidence from limited studies as they develop practices at their own institutions, which has resulted in considerably different practices globally. This review describes infection control and prevention as well as antimicrobial prophylaxis strategies in this population. Data on diagnostics and treatment for patients receiving ECMO with a focus on diagnostic and antimicrobial stewardship is then examined. This review summarizes gaps in the current ECMO literature and proposes future needs, including developing clear definitions for infections and encouraging transparent reporting of practices at individual facilities in future clinical trials.

Fatal Clostridium septicum gas gangrene complicating ECMO: case report and review of literature

Clostridium septicum gas gangrene is a severe and deadly infection caused by an anaerobic, spore-forming, Gram-positive bacillus. As previously described, two entities are observed: traumatic and spontaneous (or non-traumatic) forms. In this report, we aim to describe the case of a fulminant and ultimately fatal C. septicum myonecrosis occurring in a patient who was first admitted for refractory cardiac arrest and placed on veino-arterial extracorporeal membrane oxygenation (ECMO). Building upon prior studies that have documented cases of spontaneous gas gangrene caused by C. septicum, we provide an updated compilation, focusing on microbiological characteristics of C. septicum, along with the diagnostic and therapeutic challenges associated with spontaneous gas gangrene. Additionally, the specific clinical situation of our case illustrates the seriousness of this infectious complication that combined both spontaneous and traumatic gas gangrene risk factors. We thus, discuss the antibiotic coverage prior to the initiation of ECMO procedure.

Antibiotic Prophylaxis in Patients on Extracorporeal Membrane Oxygenation: A Systematic Review

Despite the frequent use of prophylactic antibiotics in hospitals for extracorporeal membrane oxygenation (ECMO) patients, the Extracorporeal Life Support Organization (ELSO) Infectious Disease Task Force does not recommend routine antibiotic prophylaxis due to a lack of compelling evidence. We assessed the effectiveness of prophylactic antibiotics in ECMO patients. We conducted a comprehensive search of multiple databases from their inception up to September 6, 2023, on various databases using keywords like "antibiotics," "prophylaxis," "extracorporeal membrane oxygenation," and "ECMO." Newcastle-Ottawa Scale (NOS) was used to assess the quality of the included research. We collected data using Microsoft Excel version 2016, mean and standard deviations were calculated for continuous data, while frequencies and percentages were calculated for binomial data. A total of three studies was included in the review with a total of 8,954 participants, of which 4,483 (50.06%) received antibiotic prophylaxis, and 1,131 (25.22%) were female. The administration of antibiotics prophylactically was associated with reduction in rate of mortality, the risk of infections, and complications like acute kidney injury and diarrhea. Although there have been some benefits on antibiotic prophylaxis, prospective research, and possibly the creation of tailored, ECMO-specific bundles will be needed to identify efficient ways to prevent ECMO infection.

Feasibility of veno-arterial extracorporeal life support in awake patients with cardiogenic shock

OBJECTIVES

This study sought to demonstrate outcomes of veno-arterial extracorporeal life support (VA-ECLS) in non-intubated ('awake') patients with cardiogenic shock, as very few studies have investigated safety and feasibility in this population.

METHODS

This was a retrospective review of 394 consecutive VA-ECLS patients at our institution from 2017 to 2021. We excluded patients cannulated for indications definitively associated with intubation. Patients were stratified by intubation status at time of cannulation and baseline differences were balanced by inverse probability of treatment weighting. The primary outcome was in-hospital mortality while secondary outcomes included adverse events during ECLS and destination at discharge.

RESULTS

Out of 135 patients in the final cohort, 79 were intubated and 56 were awake at time of cannulation. All awake patients underwent percutaneous femoral cannulation with technical success of 100% without intubation. Indications for VA-ECLS in awake patients included acute decompensated heart failure (64.3%), pulmonary hypertension or massive pulmonary embolism (12.5%), myocarditis (8.9%) and acute myocardial infarction (5.4%). After adjustment, awake and intubated patients had similar ECLS duration (7 vs 6 days, P = 0.19), in-hospital mortality (39.6% vs 51.7%, P = 0.28), and rates of various adverse events. Intubation status was not a significant risk factor for 90-day mortality (hazard ratio [95% confidence interval]: 1.26 [0.64, 2.45], P = 0.51) in multivariable analysis. Heart transplantation (15.1% vs 4.9%) and ventricular assist device (17.4% vs 2.2%) were more common destinations at discharge in awake patients than intubated patients (P = 0.02).

CONCLUSIONS

Awake VA-ECLS is safe and feasible with comparable outcomes as intubated counterparts in select cardiogenic shock patients.

Dynamic decline of lymphocytes predicts extracorporeal membrane oxygenation-related infections: a retrospective observational study

Background

Limited data are available regarding the current microbiological characteristics of extracorporeal membrane oxygenation (ECMO)-related infections in intensive care units (ICUs) in China. This retrospective study aimed to determine the epidemiology, risk factors and impact on the outcome of ECMO-related infections.

Methods

A retrospective observational study from January 2014 to December 2019 was performed, and adult patients receiving ECMO support for more than 48 hours were included in this study. The primary outcome was the incidence rate of ECMO-related infection. Clinical data were recorded, and risk factors associated with an increased risk of ECMO-related infection were analyzed.

Results

A total of 174 adult patients who received ECMO and underwent ECMO for 1,670 days were included in this study. Forty-six patients (26.4%) developed ECMO-related infections, corresponding to 27.5 first episodes/1,000 ECMO days. The most common ECMO-related infection observed was ventilator-associated pneumonia (VAP). Infected patients had longer durations of mechanical ventilation {20.2 [interquartile range (IQR), 12.6, 30.7] vs. 9.0 (IQR, 5.8, 14.7) days, P<0.001}, ECMO support [11.6 (IQR, 8.1, 17.3) vs. 7.6 (IQR, 5.6, 9.7) days, P<0.001] and hospital stays (28.2±20.7 vs. 22.0±15.6 days, P<0.001). The factors independently associated with ECMO-related infection were a dynamic decrease in lymphocyte count [adjusted odds ratio (OR) =3.578, 95% confidence interval (CI): 2.175-4.906, P<0.001] and ECMO duration (adjusted OR =1.207, 95% CI: 1.096-1.330, P<0.001). Compared to patients without infection, infected patients had greater hospital mortality (39.1% vs. 78.3%, P<0.001) and 90-day mortality (40.6% vs. 87.0%, P<0.001). ECMO-related infections were associated with worse outcomes (adjusted Kaplan-Meier curve, log rank test P<0.001).

Conclusions

Patients supported by ECMO had a high risk of developing ECMO-related infection. The most common ECMO-related infection observed was VAP. A dynamic decrease in lymphocyte counts was significantly associated with an increased risk of ECMO-related infection.

Contemporary Bridge to Heart Transplantation With Venoarterial Extracorporeal Membrane Oxygenation

Objective: In October 2018, the United Network for Organ Sharing changed their heart allocation criteria to prioritize patients on temporary mechanical circulatory support. This study assesses outcomes of patients bridged to orthotopic heart transplantation (OHT) with venoarterial extracorporeal membrane oxygenation (VA ECMO) since this change. Methods: We conducted a retrospective single-center study of adults (≥18 years) supported with VA ECMO at the time of OHT (October 1, 2018, to December 31, 2021). The primary outcome was midterm survival. Results: During the study period, 117 patients underwent OHT including 52 adults ≥18 years (44%) and 65 children <18 years (56%). Among adults, 8 (15%) were supported with VA ECMO at the time of OHT and are included in this study; 75% were male (n = 6), and the median age was 52.5 (interquartile range [IQR] = 23.5 to 57.25) years. Most patients were peripherally cannulated (75%, n = 6) and supported with an intra-aortic balloon pump during the pretransplant period (87.5%, n = 7). The median ECMO duration was 7 (IQR = 4.5 to 25.25) days. Three patients experienced complications on ECMO (37.5%), including thromboembolic bowel infarction (12.5%, n = 1) and bleeding requiring reintervention (25%, n = 2). All patients survived to discharge without posttransplantation complications and were alive at the latest follow-up. The median follow-up time was 24.8 (IQR = 19.5 to 28.2) months. Conclusions: Patients can be successfully bridged with VA ECMO directly to OHT with excellent midterm results. Key contributors to our outcomes include early extubation, use of bivalirudin over heparin, ambulation, and rehabilitation while on ECMO.

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.

Incidence, risk factors and outcomes of nosocomial infection in adult patients supported by extracorporeal membrane oxygenation: a systematic review and meta-analysis

BACKGROUND

An increasing number of patients requires extracorporeal membrane oxygenation (ECMO) for life support. This supportive modality is associated with nosocomial infections (NIs). This systematic review and meta-analysis aim to assess the incidence and risk factors of NIs in adult.

METHODS

We searched PubMed, Scopus, Web of Science, and ProQuest databases up to 2022. The primary endpoint was incidence of NI. Secondary endpoints included time to infection, source of infection, ECMO duration, Intensive care and hospital length of stay (LOS), ECMO survival and overall survival. Incidence of NI was reported as pooled proportions and 95% confidence intervals (CIs), while dichotomous outcomes were presented as risk ratios (RR) as the effective index and 95% CIs using a random-effects model.

RESULTS

Among the 4,733 adult patients who received ECMO support in the 30 included studies, 1,249 ECMO-related NIs per 1000 ECMO-days was observed. The pooled incidence of NIs across 18 studies involving 3424 patients was 26% (95% CI 14-38%).Ventilator-associated pneumonia (VAP) and bloodstream infections (BSI) were the most common NI sources. Infected patients had lower ECMO survival and overall survival rates compared to non-infected patients, with risk ratio values of 0.84 (95% CI 0.74-0.96, P = 0.01) and 0.80 (95% CI 0.71-0.90, P < 0.001), respectively.

CONCLUSION

Results showed that 16% and 20% lower of ECMO survival and overall survival in patients with NI than patients without NI, respectively. However, NI increased the risk of in-hospital mortality by 37% in infected patients compared with non-infected patients. In addition, this study identified the significant positive correlation between ECMO duration and ECMO-related NI.

Biofilm Assessment and Metagenomic Analysis of Venoarterial Extracorporeal Membrane Oxygenation Cannulas and Membrane Oxygenators

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) exposes the patient to infectious complications related to the cannulas or the site of insertion. The aim of the current study was to investigate and compare the prevalence of cannula and membrane oxygenators colonization using three different methods: microbiological culture, scanning electron microscopy, and metagenomic (rRNA 16S analysis). A monocentric prospective study was conducted between December 2017 and June 2018. Consecutive patients undergoing VA-ECMO support for refractory cardiac arrest or cardiogenic shock were included. Ten patients were included with a median age of 64 (52-62) years. Venoarterial extracorporeal membrane oxygenation was inserted for refractory cardiac arrest in five (50%), cardiogenic shock in four (40%), and self-poisoning in one (10%) cases. Microbiological culture of all (8/8, 100%) membrane oxygenators was negative, whereas all (10/10, 100%) were colonized by biofilm, and eight (8/9, 89%) presented bacterial DNA. Three (3/9, 33%) arterial and venous cannulas were positive in culture and seven (7/9, 78%) were colonized by biofilm, respectively. Seven (7/9, 78%) arterial and four (4/9, 44%) venous cannulas presented bacterial DNA. Colonization of cannulas and membranes is more frequent when assessed by electron microscopy or metagenomic analysis than with culture. Membrane oxygenators are more often colonized than cannulas.

Healthcare-associated infections in patients with severe COVID-19 supported with extracorporeal membrane oxygenation: a nationwide cohort study

BACKGROUND

Both critically ill patients with coronavirus disease 2019 (COVID-19) and patients receiving extracorporeal membrane oxygenation (ECMO) support exhibit a high incidence of healthcare-associated infections (HAI). However, data on incidence, microbiology, resistance patterns, and the impact of HAI on outcomes in patients receiving ECMO for severe COVID-19 remain limited. We aimed to report HAI incidence and microbiology in patients receiving ECMO for severe COVID-19 and to evaluate the impact of ECMO-associated infections (ECMO-AI) on in-hospital mortality.

METHODS

For this study, we analyzed data from 701 patients included in the ECMOSARS registry which included COVID-19 patients supported by ECMO in France.

RESULTS

Among 602 analyzed patients for whom HAI and hospital mortality data were available, 214 (36%) had ECMO-AI, resulting in an incidence rate of 27 ECMO-AI per 1000 ECMO days at risk. Of these, 154 patients had bloodstream infection (BSI) and 117 patients had ventilator-associated pneumonia (VAP). The responsible microorganisms were Enterobacteriaceae (34% for BSI and 48% for VAP), Enterococcus species (25% and 6%, respectively) and non-fermenting Gram-negative bacilli (13% and 20%, respectively). Fungal infections were also observed (10% for BSI and 3% for VAP), as were multidrug-resistant organisms (21% and 15%, respectively). Using a Cox multistate model, ECMO-AI were not found associated with hospital death (HR = 1.00 95% CI [0.79-1.26], p = 0.986).

CONCLUSIONS

In a nationwide cohort of COVID-19 patients receiving ECMO support, we observed a high incidence of ECMO-AI. ECMO-AI were not found associated with hospital death. Trial registration number NCT04397588 (May 21, 2020).

The impact of extracorporeal membrane oxygenation on antifungal pharmacokinetics: A systematic review

BACKGROUND AND OBJECTIVE

The use of extracorporeal membrane oxygenation (ECMO) as a cardiocirculatory or respiratory support has tremendously increased in critically ill patients. In the setting of ECMO support, invasive fungal infections are a severe cause of morbidity and mortality. This vulnerable population is at risk of suboptimal antifungal exposure due to an increased volume of distribution (Vd), drug sequestration and decreased clearance. Here, we aimed to summarize ex-vivo and clinical studies on the potential impact of ECMO on the pharmacokinetics (PK) of antifungal agents and dosing requirements.

METHODS

A systematic search of the literature within electronic databases PubMed and EMBASE was conducted from database inception to 30 April 2023. Inclusion criteria were as follows: critically ill patients receiving ECMO regardless of age and reporting at least one PK parameter.

RESULTS

Thirty-six studies met inclusion criteria, including seven ex-vivo experiments and 29 clinical studies evaluating three classes of antifungals: polyenes, triazoles and echinocandins. Based on the available ex-vivo PK data, we found a significant sequestration of highly lipophilic and protein-bound antifungals within the ECMO circuit such as voriconazole, posaconazole and micafungin but the PK of several antifungals remains to be addressed such as amphotericin B, isavuconazole and anidulafungin. Most clinical studies have shown increased Vd of some antifungals like fluconazole and micafungin, particularly in the pediatric population. Conflicting data exist about caspofungin exposure.

CONCLUSIONS

The available literature on the antifungal PK changes in ECMO setting is scarce. Whenever possible, therapeutic drug monitoring is highly advised to personalize antifungal therapy.

Infection in ECMO patients: Changes in epidemiology, diagnosis and prevention

Patients with prolonged duration of extracorporeal membrane oxygenation support (ECMO) are a vulnerable population for sepsis, particularly ventilator-associated pneumonia and bloodstream infections. Rates differ between venous-arterial and venous-venous ECMO patients and according to the cannulation technique used. The presence of particular organisms depends on local epidemiology, antibiotic exposure, and the duration of the intervention; patients undergoing ECMO for more than three weeks present a high risk of persistent candidemia. Recognizing predisposing factors, and establishing the best preventive interventions and therapeutic choices are critical to optimizing the management of these complications. Infection control practices, including shortening the period of the indwelling devices, and reducing antibiotic exposure, must be followed meticulously. Innovations in oxygenator membranes require an updated approach. Hand hygiene and avoiding breaking the circuit-oxygenator sterility are cornerstones. ECMO management would benefit from clearer definitions, optimization of infection control strategies, and updated infectious clinical practice guidelines.

A nomogram to predict nosocomial infection in patients on venoarterial extracorporeal membrane oxygenation after cardiac surgery

INTRODUCTION

After cardiac surgery, patients on venoarterial extracorporeal membrane oxygenation (VA-ECMO) have a higher risk of nosocomial infection in the intensive care unit (ICU). We aimed to establish an intuitive nomogram to predict the probability of nosocomial infection in patients on VA-ECMO after cardiac surgery.

METHODS

We included patients on VA-ECMO after cardiac surgery between January 2011 and December 2020 at a single center. We developed a nomogram based on independent predictors identified using univariate and multivariate logistic regression analyses. We selected the optimal model and assessed its performance through internal validation and decision-curve analyses.

RESULTS

Overall, 503 patients were included; 363 and 140 patients were randomly divided into development and validation sets, respectively. Independent predictors derived from the development set to predict nosocomial infection included older age, white blood cell (WBC) count abnormality, ECMO environment in the ICU, and mechanical ventilation (MV) duration, which were entered into the model to create the nomogram. The model showed good discrimination, with areas under the curve (95% confidence interval) of 0.743 (0.692-0.794) in the development set and 0.732 (0.643-0.820) in the validation set. The optimal cutoff probability of the model was 0.457 in the development set (sensitivity, 0.683; specificity, 0.719). The model showed qualified calibration in both the development and validation sets (Hosmer-Lemeshow test, p > .05). The threshold probabilities ranged from 0.20 to 0.70.

CONCLUSIONS

For adult patients receiving VA-ECMO treatment after cardiac surgery, a nomogram-monitoring tool could be used in clinical practice to identify patients with high-risk nosocomial infections and provide an early warning.

Prophylactic antibiotic treatment for preventing nosocomial infection in extracorporeal membrane oxygenation-resuscitated circulatory arrest patients

Objective

We aimed to investigate the characteristics of nosocomial infections (NIs) and the impact of prophylactic antibiotic administration on NI outcomes in patients who underwent extracorporeal cardiopulmonary resuscitation (ECPR).

Methods

This retrospective study analyzed the rate, type, pathogens, outcomes, and risk factors of NIs that developed in adult patients who underwent ECPR at our institution between January 2002 and January 2022.

Results

Among 105 patients (median age, 58.59 [interquartile range, 46.53-67.32] years), 57 (54.29%) patients developed NIs during their extracorporeal membrane oxygenation courses. The incidence rates per 1000 extracorporeal membrane oxygenation days were 135.91 for overall infections and 40.06 for multidrug-resistant (MDR) infections. Ventilator-associated pneumonia was the most common type of NI (73.68%), followed by bloodstream infections (17.89%). Prophylactic antibiotics with Pseudomonas aeruginosa coverage were protective factors against NI (hazard ratio [HR], 0.518; 95% confidence interval [CI], 0.281-0.953; P = .034). High dynamic driving pressure of the ventilator (cmH2O) was a prognostic factor for hospital mortality (HR, 1.096; 95% CI, 1.008-1.192; P = .032). An Acute Physiology and Chronic Health Evaluation II score of ≥24 (HR, 6.443; 95% CI, 1.380-30.088; P = .018) was a risk factor for developing MDR infections.

Conclusions

In patients who undergo ECPR, prophylactic antibiotic treatment with P aeruginosa coverage is associated with a lower incidence of NIs, whereas an Aeruginosa Acute Physiology and Chronic Health Evaluation II score of ≥24 is a risk factor for MDR infections. In the modern era of antibiotic therapy, the development of NIs does not increase hospital mortality among patients undergoing ECPR.

Veno-arterial extracorporeal membrane oxygenation as a perioperative support to redo cardiac surgery for inoperable adult patients: a case series

Background

The present article describes three cases of patients in cardiogenic shock (CS) with previous cardiac surgery that made them initially inoperable. Perioperative support with veno-arterial extracorporeal membrane oxygenation (VA-ECMO) improved haemodynamic status and results in these high-risk patients.

Case summary

Case 1 is a 57-year-old male morbidly obese with previous aortic valve replacement (AVR) who presented with chest pain and developed cardiac arrest. Cardiopulmonary resuscitation and femoral VA-ECMO were initiated. Three days later, a redo AVR was performed. Veno-arterial extracorporeal membrane oxygenation was maintained for 12 days, followed by 7 days of veno-venous ECMO for complete recovery. Case 2 features a 39-year-old male with two previous mitral valve replacements (MVRs). The first is due to papillary muscle rupture, and the second is due to endocarditis of the mitral prosthesis. He presented with CS and pulmonary oedema. Emergency surgery was performed and the patient was then placed in VA-ECMO. Weaning off was achieved 3 days after surgery. Case 3 is a 21-year-old female with a previous MVR due to rheumatic disease. She presented with CS, severe mitral prosthesis stenosis, and a pulmonary embolism. Femoral VA-ECMO was initiated, and one day later, she underwent a redo MVR operation. Extracorporeal membrane oxygenation was discontinued 4 days later.

Discussion

Dysfunctional prosthetic valves leading to CS may benefit from a redo cardiac operation supported by a perioperative VA-ECMO to optimize haemodynamic status. Despite the results from risk prediction scores, this approach has the potential to reduce operative mortality in initial inoperable patients and allow a definitive redo cardiac surgery.

Extending the 'host response' paradigm from sepsis to cardiogenic shock: evidence, limitations and opportunities

Recent clinical and research efforts in cardiogenic shock (CS) have largely focussed on the restoration of the low cardiac output state that is the conditio sine qua non of the clinical syndrome. This approach has failed to translate into improved outcomes, and mortality has remained static at 30-50%. There is an unmet need to better delineate the pathobiology of CS to understand the observed heterogeneity of presentation and treatment effect and to identify novel therapeutic targets. Despite data in other critical illness syndromes, specifically sepsis, the role of dysregulated inflammation and immunity is hitherto poorly described in CS. High-dimensional molecular profiling, particularly through leukocyte transcriptomics, may afford opportunity to better characterise subgroups of patients with shared mechanisms of immune dysregulation. In this state-of-the-art review, we outline the rationale for considering molecular subtypes of CS. We describe how high-dimensional molecular technologies can be used to identify these subtypes, and whether they share biological features with sepsis and other critical illness states. Finally, we propose how the identification of molecular subtypes of patients may enrich future clinical trial design and identification of novel therapies for CS.

Bloodstream infections in COVID-19 patients undergoing extracorporeal membrane oxygenation in ICU: An observational cohort study

BACKGROUND

COVID-19 patients undergoing ECMO are at highly increased risk of nosocomial infections.

OBJECTIVES

To study incidence, clinical outcomes and microbiological features of bloodstream infections (BSI) occurring during ECMO in COVID-19 patients.

METHODS

Observational prospective cohort study enrolling consecutive COVID-19 patients undergoing veno-venous-ECMO in an Italian ICU from March 2020 to March 2022.

RESULTS

In the study population of 68 patients (age 53 [49-60] years, 82% males), 30 (44%) developed bloodstream infections (BSI group) while 38 did not (N-BSI group) with an incidence of 32 events/1000 days of ECMO. In BSI group pre-ECMO respiratory support was shorter (6 [4-9] vs 9 [5-12] days, p = 0.02) and ECMO treatment was longer (18 [10-29] vs 11 [7-18] days, p = 0.03) than in N-BSI group. The overall ECMO and ICU mortality were 50% and 59%, respectively, without any inter-group difference (p = 1.00). A longer ECMO treatment was independently correlated with higher rate of BSI (p = 0.04, OR [95% CI] 1.06 [1.02-1.11]). Sixteen primary and 14 secondary infectious events were documented. Gram-positive pathogens were more common in primary than secondary BSI (88% vs 43%, p = 0.02) and Enterococcus faecalis (56%) was the most frequent one. Conversely, Gram-negative microorganisms were more often isolated in secondary rather than primary BSI (57% vs 13%, p = 0.02), with Acinetobacter baumannii (21%) and Pseudomonas aeruginosa (21%) as most represented species. The administration of Sars-CoV-2 antiviral drug showed independent correlation with a reduced rate of ICU mortality (p = 0.01, OR [95% CI] 0.22 [0.07-0.73]).

CONCLUSIONS

Bloodstream infections represented a frequent complication without worsening clinical outcomes in our COVID-19 patients undergoing ECMO. Primary and secondary BSI events showed peculiar microbiological profiles.

Nosocomial infections in adult patients receiving extracorporeal membrane oxygenation in China: A retrospective cohort study

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) has been increasingly used in China, but nosocomial infections (NI) in patients receiving ECMO remain poorly characterized. Thus, this study aimed to investigate the incidence rate, causative was pathogens, and risk factors of NIs in ECMO patients.

METHODS

A retrospective cohort study of patients receiving ECMO between January 2015 and October 2021 was conducted in a tertiary hospital. General demographics and clinical data of the included patients were collected from the electronic medical record system and the real-time NI surveillance system.

RESULTS

A total of 86 infected patients with 110 episodes of NIs were identified in 196 patients receiving ECMO. The incidence of NI was 59.2/1000 ECMO days. The median time for the first NI in ECMO patients was 5 days (interquartile range: 2-8 days). Hospital-acquired pneumonia and bloodstream infections were common types of NIs in ECMO patients, and the main pathogens were gram-negative bacteria. Pre-ECMO invasive mechanical ventilation (OR = 2.40, 95% CI:1.12-5.15) and prolonged duration of ECMO (OR = 1.26, 95% CI:1.15-1.39) were risk factors for NIs during ECMO support.

DISCUSSION

This study identified the main infection sites and pathogens of NIs in ECMO patients. Although NIs may not affect successful ECMO weaning, additional measures should be implemented to reduce the incidence of NI during ECMO support.

Systematic Assessment of Shock Severity in Postoperative Cardiac Surgery Patients

BACKGROUND

The Society for Cardiovascular Angiography and Interventions (SCAI) shock classification has been shown to provide robust mortality risk stratification in a variety of cardiovascular patients.

OBJECTIVES

This study sought to evaluate the SCAI shock classification in postoperative cardiac surgery intensive care unit (CSICU) patients.

METHODS

This study retrospectively analyzed 26,792 postoperative CSICU admissions at a heart center between 2012 and 2022. Patients were classified into SCAI shock stages A to E using electronic health record data. Moreover, the impact of late deterioration (LD) as an additional risk modifier was investigated.

RESULTS

The proportions of patients in SCAI shock stages A to E were 24.4%, 18.8%, 8.4%, 35.5%, and 12.9%, and crude hospital mortality rates were 0.4%, 0.6%, 3.3%, 4.9%, and 30.2%, respectively. Similarly, the prevalence of postoperative complications and organ dysfunction increased across SCAI shock stages. After multivariable adjustment, each higher SCAI shock stage was associated with increased hospital mortality (adjusted OR: 1.26-16.59) compared with SCAI shock stage A, as was LD (adjusted OR: 8.2). The SCAI shock classification demonstrated a strong diagnostic performance for hospital mortality (area under the receiver operating characteristic: 0.84), which noticeably increased when LD was incorporated into the model (area under the receiver operating characteristic: 0.90).

CONCLUSIONS

The SCAI shock classification effectively risk-stratifies postoperative CSICU patients for mortality, postoperative complications, and organ dysfunction. Its application could, therefore, be extended to the field of cardiac surgery as a triage tool in postoperative care and as a selection criterion in research.

One-Year Survival for Developing Acute Kidney Injury in Adult Patients with AMI Cardiogenic Shock Receiving Venoarterial Extracorporeal Membrane Oxygenation

Objective

The incidence of cardiogenic shock cases treated with veno-arterial extracorporeal membrane oxygenation (VA-ECMO) support has been on the rise. Acute kidney injury (AKI) is a significant complication of cardiogenic shock and a frequent serious complication in patients requiring ECMO-supported therapy. AKI is strongly associated with unfavorable patient prognosis. However, there is a paucity of data on the influence of AKI on the prognosis of patients with acute myocardial infarction complicated by cardiogenic shock (AMI-CS) who are receiving ECMO support, particularly with regard to long-term outcomes.

Methods

This retrospective observational study included 103 patients in the People's Hospital of Guangxi Zhuang Autonomous Region from January 2017 and June 2022. AKI was defined according to Kidney Disease Improving Global Outcome (KDIGO) criteria. Cox regression and logistic regression were used to identify risk factors.

Results

In this study, the incidence of AKI was 63.11%, with AKI stage 1, 2, and 3 accounting for 21.36%, 12.62%, and 29.13%, respectively. Patients with severe AKI had significantly higher in-hospital mortality (43.33% vs 27.40%, P < 0.001), 30-day mortality (60.00% vs 31.51%, P = 0.001), and 1-year mortality (63.67% vs 34.25%, P<0.001) than those without severe AKI. Furthermore, severe AKI significantly increased the risk of one-year mortality (HR 10.816, CI 3.118-37.512, P<0.001). Baseline serum creatinine, baseline platelet, and active cardiopulmonary resuscitation were independent predictors of one-year mortality. In addition, baseline white blood cell count, baseline aspartate aminotransferase, baseline alanine aminotransferase (ALT), baseline serum creatinine, preoperative lactate, and postoperative mean arterial pressure were independent risk factors of severe AKI during hospitalization.

Conclusion

In patients with AMI-CS receiving ECMO support, AKI is highly prevalent. Development of severe AKI significantly increased the risk of one-year mortality.

Bloodstream infection and ventilator-associated pneumonia in patients with coronavirus disease 2019 (COVID-19) supported by extracorporeal membrane oxygenation

OBJECTIVE

Extracorporeal membrane oxygenation (ECMO) has been widely used in the care of patients with respiratory failure from coronavirus disease 2019 (COVID-19). We characterized bloodstream infections (BSIs) and ventilator-associated pneumonias (VAPs) in COVID-19 patients supported with ECMO, and we investigated their impact on patient outcomes.

DESIGN

Retrospective cohort study from March 1, 2020, to June 30, 2021.

SETTING

Academic tertiary-care referral center.

PATIENTS

Consecutive adult patients admitted for COVID-19 who received ECMO.

METHODS

We identified BSIs and VAPs and described their epidemiology and microbiology. Cumulative antimicrobial use and the specific management of BSIs were determined. Multivariate time-dependent Cox proportional hazards models were constructed to evaluate the impact of BSIs and VAPs on mortality, controlling for age, receipt of COVID-19-specific therapeutics, and new renal replacement therapy.

RESULTS

We identified 136 patients who received ECMO for COVID-19 pneumonia during the study period. BSIs and VAPs occurred in 81 patients (59.6%) and 93 patients (68.4%), respectively. The incidence of BSIs was 29.5 per 1,000 ECMO days and increased with duration of ECMO cannulation. Enterococci, Enterobacterales, and Staphylococcus aureus were the most common causes of BSIs, whereas S. aureus, Klebsiella species, and Pseudomonas aeruginosa comprised the majority of VAPs. Mean antibiotic use comprised 1,031 days of therapy per 1,000 ECMO days (SD, 496). We did not detect an association between BSIs or VAPs and mortality.

CONCLUSIONS

BSIs and VAPs are common in COVID-19 ECMO-supported patients. Efforts to optimize their diagnosis, prevention, and management should be prioritized.

Treatment and outcome of gram-positive bacteremia in patients receiving extracorporeal membrane oxygenation

BACKGROUND

While guidance exists for management of blood stream infections with various invasive devices, there are currently limited data to guide antibiotic selection and duration for bacteremia in patients receiving extracorporeal membrane oxygenation (ECMO).

OBJECTIVE

To evaluate the treatment and outcomes of thirty-six patients with Staphylococcus aureus and Enterococcus bacteremia on ECMO support.

METHODS

Blood culture data was retrospectively analyzed from patients with Staphylococcus aureus bacteremia (SAB) or Enterococcus bacteremia who underwent ECMO support between March 2012 and September 2021 at Brooke Army Medical Center.

RESULTS

Of the 282 patients who received ECMO during this study period, there 25 (9%) patients developed Enterococcus bacteremia and 16 (6%) developed SAB. SAB occurred earlier in ECMO as compared to Enterococcus (median day 2 IQR (1-5) vs. 22 (12-51), p = 0.01). The most common duration of antibiotics was 28 days after clearance for SAB and 14 days after clearance for Enterococcus. 2 (5%) patients underwent cannula exchange with primary bacteremia, and 7 (17%) underwent circuit exchange. 1/3 (33%) patients with SAB and 3/10 (30%) patients with Enterococcus bacteremia who remained cannulated after completion of antibiotics had a second episode of SAB or Enterococcus bacteremia.

CONCLUSION

This single center case series is the first to describe the specific treatment and outcomes of patients receiving ECMO complicated by SAB and Enterococcus bacteremia. For patients who remain on ECMO after completion of antibiotics, there is a risk of a second episode of Enterococcus bacteremia or SAB.

Antifungal Dosing in Critically Ill Patients on Extracorporeal Membrane Oxygenation

Extracorporeal membrane oxygenation (ECMO) is an established advanced life support system, providing temporary cardiac and/or respiratory support in critically ill patients. Fungal infections are associated with increased mortality in patients on ECMO. Antifungal drug dosing for critically ill patients is highly challenging because of altered pharmacokinetics (PK). PK changes during critical illness; in particular, the drug volume of distribution (Vd) and clearance can be exacerbated by ECMO. This article discusses the available literature to inform adequate dosing of antifungals in this patient population. The number of antifungal PK studies in critically ill patients on ECMO is growing; currently available literature consists of case reports and studies with small sample sizes providing inconsistent findings, with scant or no data for some antifungals. Current data are insufficient to provide definitive empirical drug dosing guidance and use of dosing strategies derived from critically patients not on ECMO is reasonable. However, due to high PK variability, therapeutic drug monitoring should be considered where available in critically ill patients receiving ECMO to prevent subtherapeutic or toxic antifungal exposures.

Impact of Nosocomial Infection on in-Hospital Mortality Rate in Adult Patients Under Venoarterial Extracorporeal Membrane Oxygenation After Cardiac Surgery

Objective

There was no consensus on the impact of nosocomial infection on In-hospital mortality rate in patients receiving ECMO. This study aimed to investigate the impact of nosocomial infection (NI) on In-hospital mortality rate in adult patients receiving venoarterial extracorporeal membrane oxygenation (VA-ECMO) after cardiac surgery.

Materials and Methods

This retrospective study included 503 adult patients who underwent VA-ECMO after cardiac surgery. The impact of time-dependent NIs on In-hospital mortality rate within 28 days of ECMO initiation was investigated using a Cox regression model. The cumulative incidence function for death was compared between patients with NIs and those without NIs using a competing risk model.

Results

Within 28 days after ECMO initiation, 206 (41.0%) patients developed NIs, and 220 (43.7%) patients died. The prevalence rates of NIs were 27.8% and 20.3% during and after ECMO therapy, respectively. The incidence rates of NIs during and after ECMO therapy were 49‰ and 25‰, respectively. Time-dependent NI was an independent risk factor for predicting death (hazard ratio = 1.05, 95% confidence interval = 1.00-1.11). The cumulative incidence of death in patients with NI was significantly higher than that in patients without NI at each time point within 28 days of ECMO initiation. (Z = 5.816, P = 0.0159).

Conclusion

NI was a common complication in adult patients who received VA-ECMO after cardiac surgery, and time-dependent NI was an independent risk factor for predicting mortality in these patients. Using a competing risk model, we confirmed that NIs increased the risk of In-hospital mortality rate in these patients.

Antibiotic stewardship in the ICU: time to shift into overdrive

Antibiotic resistance is a major health problem and will be probably one of the leading causes of deaths in the coming years. One of the most effective ways to fight against resistance is to decrease antibiotic consumption. Intensive care units (ICUs) are places where antibiotics are widely prescribed, and where multidrug-resistant pathogens are frequently encountered. However, ICU physicians may have opportunities to decrease antibiotics consumption and to apply antimicrobial stewardship programs. The main measures that may be implemented include refraining from immediate prescription of antibiotics when infection is suspected (except in patients with shock, where immediate administration of antibiotics is essential); limiting empiric broad-spectrum antibiotics (including anti-MRSA antibiotics) in patients without risk factors for multidrug-resistant pathogens; switching to monotherapy instead of combination therapy and narrowing spectrum when culture and susceptibility tests results are available; limiting the use of carbapenems to extended-spectrum beta-lactamase-producing Enterobacteriaceae, and new beta-lactams to difficult-to-treat pathogen (when these news beta-lactams are the only available option); and shortening the duration of antimicrobial treatment, the use of procalcitonin being one tool to attain this goal. Antimicrobial stewardship programs should combine these measures rather than applying a single one. ICUs and ICU physicians should be at the frontline for developing antimicrobial stewardship programs.

Nosocomial Infections in Adult Patients Supported by Extracorporeal Membrane Oxygenation in a Cardiac Intensive Care Unit

The use of venoarterial (VA) extracorporeal membrane oxygenation therapy (ECMO) in patients admitted to cardiac intensive care units (CICU) has increased. Data regarding infections in this population are scarce. In this retrospective study, we analyzed the risk factors, outcome, and predictors of in-hospital mortality due to nosocomial infections in patients with ECMO admitted to a single coronary intensive care unit between July 2013 and March 2019 treated with VA-ECMO for >48 h. From 69 patients treated with VA-ECMO >48 h, (median age 58 years), 29 (42.0%) patients developed 34 episodes of infections with an infection rate of 0.92/1000 ECMO days. The most frequent were ventilator-associated pneumonia (57.6%), tracheobronchitis (9.1%), bloodstream infections (9.1%), skin and soft tissue infections (9.1%), and cytomegalovirus reactivation (9.1%). In-hospital mortality was 47.8%, but no association with nosocomial infections was found (p = 0.75). The number of days on ECMO (OR 1.14, 95% CI 1.01-1.30, p = 0.029) and noninfectious complications were higher in the infected patients (OR: 3.8 95% CI = 1.05-14.1). A higher baseline creatinine value (OR: 8.2 95% CI = 1.12-60.2) and higher blood lactate level at 4 h after ECMO initiation (OR: 2.0 95% CI = 1.23-3.29) were significant and independent risk factors for mortality. Conclusions: Nosocomial infections in medical patients treated with VA-ECMO are very frequent, mostly Gram-negative respiratory infections. Preventive measures could play an important role for these patients.

Multiple-site decontamination to prevent acquired infection in patients with veno-venous ECMO support

BACKGROUND

Acute distress respiratory syndrome (ARDS) patients with veno-venous extra corporeal membrane oxygenation (ECMO) support are particularly exposed to ECMO-associated infection (ECMO-AI). Unfortunately, data regarding AI prophylaxis in this setting are lacking. Selective decontamination regimens decrease AI incidence, including ventilator-associated pneumonia (VAP) and bloodstream infection (BSI) in critically ill patients. We hypothesized that a multiple-site decontamination (MSD) regimen is associated with a reduction in the incidence of AI among VV-ECMO patients.

METHODS

We conducted a retrospective observational study in three French ECMO referral centers from January 2010 to December 2021. All adult patients (> 18 years old) who received VV-ECMO support for ARDS were eligible. In addition to standard care (SC), 2 ICUs used MSD, which consists of the administration of topical antibiotics four times daily in the oropharynx and the gastric tube, once daily chlorhexidine body-wash and a 5-day nasal mupirocin course. AIs were compared between the 2 ICUs using MSD (MSD group) and the last ICU using SC.

RESULTS

They were 241 patients available for the study. Sixty-nine were admitted in an ICU that applied MSD while the 172 others received standard care and constituted the SC group. There were 19 ECMO-AIs (12 VAP, 7 BSI) in the MSD group (1162 ECMO-days) compared to 143 AIs (104 VAP, 39 BSI) in the SC group (2376 ECMO-days), (p < 0.05 for all infection site). In a Poisson regression model, MSD was independently associated with a lower incidence of ECMO-AI (IRR = 0.42, 95% CI [0.23-0.60] p < 0.001). There were 30 multidrug resistant microorganisms (MDRO) acquisition in the SC group as compared with two in the MSD group (IRR = 0.13, 95% CI [0.03-0.56] p = 0.001). Mortality in ICU was similar in both groups (43% in the SC group vs 45% in the MSD group p = 0.90). Results were similar after propensity-score matching.

CONCLUSION

In this cohort of patients from different hospitals, MSD appeared to be safe in ECMO patients and may be associated with improved outcomes including lower ECMO-AI and MDRO acquisition incidences. Since residual confounders may persist, these promising results deserve confirmation by randomized controlled trials.

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).

The Influence of Extracorporeal Membrane Oxygenation on Antibiotic Pharmacokinetics

Extracorporeal membrane oxygenation (ECMO) is becoming increasingly utilized to support critically ill patients who experience life-threatening cardiac or pulmonary compromise. The provision of this intervention poses challenges related to its complications and the optimization of medication therapy. ECMO's mechanical circulatory support is facilitated via various devices and equipment that have been shown to sequester lipophilic- and protein-bound medications, including anti-infectives. Since infectious outcomes are dependent on achieving specific anti-infectives' pharmacodynamic targets, the understanding of these medications' pharmacokinetic parameters in the setting of ECMO is important to clinicians. This narrative, non-systematic review evaluated the findings of the most recent and robust pharmacokinetic analyses for commonly utilized anti-infectives in the setting of ECMO. The data from available literature indicates that anti-infective pharmacokinetic parameters are similar to those observed in other non-ECMO critically ill populations, but considerable variability in the findings was observed between patients, thus prompting further evaluation of therapeutic drug monitoring in this complex population.

Sepsis in postcardiotomy cardiogenic shock patients supported with veno- arterial extracorporeal membrane oxygenation

BACKGROUND

Sepsis could affect the outcomes of patients with postcardiotomy cardiogenic shock supported with extracorporeal membrane oxygenation (ECMO). Our objectives were to characterize sepsis patients with ECMO support for postcardiotomy cardiogenic shock and assess its predictors and effect on patients' outcomes.

METHODS

This retrospective study included 103 patients with ECMO for postcardiotomy cardiogenic shock from 2009 to 2020. Patients were divided according to the occurrence and timing of sepsis into three groups. Group 1 included patients with no sepsis (n = 67), Group 2 included patients with ECMO-related sepsis (n = 10), and Group 3 included patients with non-ECMO-related sepsis (n = 26).

RESULTS

Lactate level before ECMO was highest in the ECMO-associated sepsis group (Group 1 and 2 p = 0.003 and Group 2 and 3 p = 0.003). Dialysis and gastrointestinal bleeding were highest in ECMO-associated sepsis (p = 0.03 and 0.04, respectively). Blood transfusion was higher in ECMO-associated sepsis than in patients with no sepsis (p = 0.01). Mortality was nonsignificantly higher in patients with ECMO-associated sepsis. High BMI (OR: 1.11; p = 0.004), preoperative dialysis (OR: 7.35; p = 0.02), preoperative IABP (OR: 9.9.61; p = 0.01) and CABG (OR: 6.29; p = 0.01) were significantly associated with sepsis. Older age (OR: 1.08; p = 0.004), lower BSA (OR: 0.004; p = 0.003), peripheral cannulation (OR: 29.82; p = 0.03), and high pre ECMO lactate level (OR: 1.24; p = 0.001) were associated with increased mortality. Sepsis did not predict mortality (OR: 1.83; p = 0.21).

CONCLUSIONS

Sepsis is a dreaded complication in patients with postcardiotomy cardiogenic shock, especially ECMO-associated sepsis. Preoperative risk factors could predict postoperative sepsis in ECMO patients.