Complication patterns in patients undergoing venoarterial extracorporeal membrane oxygenation in intensive care unit: Multiple correspondence analysis and hierarchical ascendant classification

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.

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.

Sepsis Associated with Extracorporeal Membrane Oxygenation

Sepsis in patients on extracorporeal membrane oxygenation (ECMO) remains a serious complication. Its presence is a poor prognostic marker and increases overall mortality. Adult patients with prolonged duration on ECMO are at high risk of developing sepsis. Ventilator-associated pneumonia and bloodstream infections are the main sources of infection these patients. A strong early suspicion, drawing adequate volume for blood cultures, and early and timely administration of empirical antibiotics can help control the infection and decrease the morbidity and mortality. The diagnostic and the treatment are both challenging. Cardiac patients have increased risk of nosocomial infection while on ECMO, which may be in part due to longer cannulation times, as well as increased likelihood of undergoing major procedures or having an open chest.

Infections Acquired During Venoarterial Extracorporeal Membrane Oxygenation Postcardiac Surgery in Children: A Retrospective Observational Study

Introduction Extracorporeal membrane oxygenation (ECMO) is increasingly being used in refractory cardiac and pulmonary dysfunction as a rescue modality. The common indications for establishing venoarterial ECMO (VA-ECMO) support in children postcardiac surgery are failure to wean from cardiopulmonary bypass (CPB), postcardiotomy cardiogenic shock (PCCS), refractory pulmonary arterial hypertension, and as a bridge to recovery or transplant. The survival rate of children on VA-ECMO support is 45%. The most frequently encountered complications during VA-ECMO are bleeding, thrombosis, acute kidney injury, and infections. Among those, infections acquired during VA-ECMO lead to high morbidity and mortality. Hence, this study aimed to determine infection rates, causal microorganisms, and mortality risk factors in children developing an infection during VA-ECMO therapy.

Methods This retrospective observational study was conducted on 106 children under 14 years of age who underwent elective or emergent cardiac surgery (between 2016 and 2020) and required VA-ECMO support. Medical records were reviewed to collect the targeted variables and analyzed.

Results Out of 106 children, 49 (46.23%) acquired infections representing a prevalence of 46.23% and an infection rate of 186.4 episodes per 1,000 ECMO days. Prevalence and acquired infection rate/1,000 ECMO days were higher in the nonsurvivor group than in the survivor group (26.42 vs.19.81%) and (215.07 vs. 157.49), respectively. The bloodstream infection (BSI) and catheter-associated urinary tract infection (CAUTI) episodes were 53.04 and 68.19 per 1,000 ECMO days, and the ventilator-associated pneumonia (VAP) rate was 44.50 per 1,000 ventilator days. The mean preoperative admission duration, aortic cross-clamping duration, CPB duration (minutes), and vasoactive-inotropic score were higher in the nonsurviving children (p < 0.001). Similarly, prolonged mean ECMO duration was also found in the nonsurvivor group compared with the survivor group (p = 0.03).

Conclusion In our study, the prevalence of acquired infection during VA-ECMO was 46.23%. The incidence of BSI, CAUTI, and VAP per 1,000 ECMO days was higher in the nonsurvivor group than in survivors. Acinetobacter baumannii was the most common cultured gram-negative organism in VAP and BSI, with 67.65% Acinetobacter spp. resistant to carbapenems. CAUTI was predominately due to Candida species during VA-ECMO.

Mortality Trends after Extracorporeal Membrane Oxygenation Support: A Korean Nationwide Cohort

BACKGROUND

This study aimed to investigate the prevalence of 7-, 30-, 60-, and 365-day overall and cause-specific mortality following extracorporeal membrane oxygenation (ECMO) support.

METHODS

The National Health Insurance claims database in South Korea was the data source for this population-based cohort study. We enrolled all adult patients aged ≥18 years receiving intensive care unit ECMO support from January 1, 2005 to December 31, 2018. The study population was divided into three groups based on the main diagnoses during ECMO support: 1) cardiovascular, 2) respiratory, and 3) other diagnoses group (all other main diagnoses rather than cardiovascular or respiratory diseases).

RESULTS

A total of 18,697 patients were included in the final analysis (64.5%, 10.9%, and 24.6% in the cardiovascular, respiratory, and other groups, respectively). The corresponding 7-, 30-, 60-, and 365-day mortality rates in these groups were 33.1%, 56.1%, 62.4%, and 67.7%. Kaplan-Meier curves demonstrated that the median survival time was shortest in the cardiovascular group (12.0 days, 95% confidence interval [CI]: 11.3-12.7), with 31.0 (95% CI: 28.5-33.6) and 49.0 (95% CI: 44.4-57.6) day survival in the respiratory and other diagnoses groups (p<0.001).

CONCLUSIONS

Approximately one-third of patients died within 7 days, half of the patients died within 30 days, and two-thirds died within 365 days of ECMO support. Overall survival time was shortest in the cardiovascular group, followed by that of the respiratory group.

End-stage Renal Disease and Long-term Survival Among Survivors of Extracorporeal Membrane Oxygenation

We aimed to investigate the prevalence and associated factors of newly diagnosed end-stage renal disease (ESRD) requiring renal-replacement therapy (RRT) among survivors of extracorporeal membrane oxygenation (ECMO) and determine whether newly diagnosed ESRD is associated with poorer long-term survival outcomes. All adult patients who underwent ECMO between 2005 and 2018 were included, and ECMO survivors were those who survived more than 365 days after ECMO support. ECMO survivors with a history of pre-ECMO RRT were excluded. A total of 5,898 ECMO survivors were included in the analysis. At the 1-year post-ECMO follow-up, 447 patients (7.6%) were newly diagnosed with ESRD requiring RRT. Preexisting renal disease (odds ratio [OR]: 2.83), increased duration of continuous RRT during hospitalization (OR: 1.16), the cardiovascular group (vs. respiratory group; OR: 1.78), and the postcardiac arrest group (vs. respiratory group; OR: 2.52) were associated with newly diagnosed ESRD. Moreover, patients with newly diagnosed ESRD were associated with a 1.56-fold higher risk of 3-year all-cause mortality than those in the control group (hazard ratio: 1.56). At the 1-year post-ECMO follow-up, 7.6% of ECMO survivors were newly diagnosed with ESRD requiring RRT. Moreover, post-ECMO ESRD was associated with poorer long-term survival among ECMO survivors.

Insomnia disorder and long-term mortality in adult patients treated with extracorporeal membrane oxygenation in South Korea

We investigated the prevalence of insomnia in extracorporeal membrane oxygenation (ECMO)-treated patients and examined the association between post-ECMO insomnia disorder and long-term mortality. In the present population-based cohort study, we used data from the National Health Insurance Claims database in South Korea. All adult patients who underwent ECMO between 2006 and 2014 were included, and ECMO-treated patients were defined as those who survived >365 days after ECMO. Insomnia disorder was identified using the International Classification of Diseases 10th Revision codes G47.0 and F51.0. Overall, 3,055 ECMO-treated patients were included in the final analysis: 431 (14.1%) had pre-ECMO insomnia disorder, while 148 (4.8%) were newly diagnosed with insomnia disorder up to 1 year after ECMO. In multivariable Cox regression model, patients with post-ECMO insomnia disorder had higher 5-year all-cause mortality (ACM) than controls (hazard ratio [HR] 1.71, 95% confidence interval [CI] 1.21-2.42; p = 0.003); however, those with pre-ECMO insomnia disorder did not (p = 0.655). In sensitivity analysis, post-ECMO insomnia disorder with underlying psychiatric illness was associated with a 2.39-fold higher 5-year ACM in ECMO-treated patients (HR 2.39, 95% CI 1.52-3.75; p < 0.001). In conclusion, at 1-year after ECMO, 4.8% of ECMO-treated patients were newly diagnosed with insomnia disorder, and post-ECMO insomnia disorder was associated with higher 5-year ACM, especially in those with underlying psychiatric illness. Our present results suggest that the development of insomnia disorder might be related to poorer long-term survival in ECMO-treated patients, especially in case of underlying psychiatric illness.

Infectious complications associated with short-term mechanical circulatory support in urgent heart transplant candidates

INTRODUCTION AND OBJECTIVES

Short-term mechanical circulatory support is frequently used as a bridge to heart transplant in Spain. The epidemiology and prognostic impact of infectious complications in these patients are unknown.

METHODS

Systematic description of the epidemiology of infectious complications and analysis of their prognostic impact in a multicenter, retrospective registry of patients treated with short-term mechanical devices as a bridge to urgent heart transplant from 2010 to 2015 in 16 Spanish hospitals.

RESULTS

We studied 249 patients, of which 87 (34.9%) had a total of 102 infections. The most frequent site was the respiratory tract (n=47; 46.1%). Microbiological confirmation was obtained in 78 (76.5%) episodes, with a total of 100 causative agents, showing a predominance of gram-negative bacteria (n=58, 58%). Compared with patients without infection, those with infectious complications showed higher mortality during the support period (25.3% vs 12.3%, P=.009) and a lower probability of receiving a transplant (73.6% vs 85.2%, P=.025). In-hospital posttransplant mortality was similar in the 2 groups (with infection: 28.3%; without infection: 23.4%; P=.471).

CONCLUSIONS

Patients supported with temporary devices as a bridge to heart transplant are exposed to a high risk of infectious complications, which are associated with higher mortality during the organ waiting period.

Concurrent Use of Renal Replacement Therapy during Extracorporeal Membrane Oxygenation Support: A Systematic Review and Meta-Analysis

Patients supported with extracorporeal membrane oxygenation (ECMO) often receive renal replacement therapy (RRT). We conducted this systematic review and meta-analysis (between January 2000 and September 2020) to assess outcomes in patients who received RRT on ECMO. Random-effects meta-analyses were performed using R 3.6.1 and certainty of evidence was rated using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach. The primary outcome was pooled mortality. The duration of ECMO support and ICU/hospital lengths of stay were also investigated. Meta-regression analyses identified factors associated with mortality. A total of 5896 adult patients (from 24 observational studies and 1 randomised controlled trial) were included in this review. Overall pooled mortality due to concurrent use of RRT while on ECMO from observational studies was 63.0% (95% CI: 56.0–69.6%). In patients receiving RRT, mortality decreased by 20% in the last five years; the mean duration of ECMO support and ICU and hospital lengths of stay were 9.33 days (95% CI: 7.74–10.92), 15.76 days (95% CI: 12.83–18.69) and 28.47 days (95% CI: 22.13–34.81), respectively, with an 81% increased risk of death (RR: 1.81, 95% CI: 1.56–2.08, p < 0.001). RRT on ECMO was associated with higher mortality rates and a longer ICU/hospital stay compared to those without RRT. Future research should focus on minimizing renal dysfunction in ECMO patients and define the optimal timing of RRT initiation.

Sepsis and ECMO

Sepsis is being recognized as an important complication of extracorporeal membrane oxygenation (ECMO) and its presence is a poor prognostic marker and increases the overall mortality. The survival rate differs in the various types of cannulation techniques. Adult patients with prolonged duration of ECMO constitute the major risk population. Ventilator-associated pneumonia and bloodstream infections form the main sources of sepsis in these patients. It is important to know the most common etiological agents for sepsis in ECMO, which varies partly with the local epidemiology of the hospitals. A high index of suspicion, drawing adequate volumes for blood culture and early and timely administration of appropriate empirical antimicrobials can substantially decrease the morbidity and mortality in this high-risk population. The dosing of antimicrobials is influenced by the pharmacological variations on ECMO machine and is an important consideration. Infection control practices are of paramount importance and need to be followed meticulously to prevent sepsis in ECMO.

Fatal pulmonary hemorrhage due to severe mitral regurgitation during venoarterial extracorporeal membrane oxygenation

Pulmonary hemorrhage (PH) during venoarterial extracorporeal membrane oxygenation (VA-ECMO) has been primarily reported in pediatric patients. We report a case of fatal PH during VA-ECMO for cardiogenic shock after myocardial infarction (MI). PH, in this case, was secondary to a triad of aortic insufficiency, left ventricle distension, and severe laminar mitral regurgitation. This case scenario, previously unreported in adults, illustrates the need for the echocardiographic assessment of left-sided heart valves prior to VA-ECMO initiation after MI as well as management considerations for massive PH in this context.

Neurological Pupil index for Early Prognostication After Venoarterial Extracorporeal Membrane Oxygenation

BACKGROUND

Venoarterial extracorporeal membrane oxygenation therapy (VA-ECMO) after refractory cardiogenic shock or cardiac arrest has significant morbidity and mortality. Early outcome prediction is crucial in this setting, but data on neuroprognostication are limited. We examined the prognostic value of clinical neurologic examination, using an automated device for the quantitative measurement of pupillary light reactivity.

METHODS

An observational cohort of sedated, mechanically ventilated VA-ECMO patients was analyzed during the early phase after ECMO insertion (first 72 h). Using the NPi-200 automated infrared pupillometer, pupillary light reactivity was assessed repeatedly (every 12 h) by calculating the Neurological Pupil index (NPi). Trends of NPi over time were correlated to 90-day mortality, and the prognostic performance of the NPi, alone and in combination with the 12-h PREDICT VA-ECMO score, was evaluated.

RESULTS

One hundred consecutive patients were studied (51 with refractory cardiogenic shock and 49 with refractory cardiac arrest; 12-h PREDICT VA-ECMO, 40%; observed 90-day survival, 43%). Nonsurvivors (n = 57) had significantly lower NPi than did survivors at all time points (all P < .01). Abnormal NPi (< 3, at any time from 24 to 72 h) was 100% specific for 90-day mortality, with 0% false positives. Adding the 12-h PREDICT VA-ECMO score to the NPi provided the best prognostic performance (specificity, 100% [95% CI, 92%-100%]; sensitivity, 60% [95% CI, 46%-72%]; area under the receiver operating characteristic curve, 0.82).

CONCLUSIONS

Quantitative NPi alone had excellent ability to predict a poor outcome from day 1 after VA-ECMO insertion, with no false positives. Combining NPi and 12-h PREDICT-VA ECMO score increased the sensitivity of outcome prediction, while maintaining 100% specificity.