Extracorporeal membrane oxygenation in adults with severe respiratory failure: a multi-center database. Intensive Care Med. 2009;35:2105-2114. [PMID: 19768656 DOI: 10.1007/s00134-009-1661-7]

Race-Conscious Research Using Extracorporeal Life Support Organization Registry Data: A Narrative Review

Race-conscious research identifies health disparities with 1) rigorous and responsible data collection, 2) intentionality and considered analyses, and 3) interpretation of results that advance health equity. Individual registries must overcome specific challenges to promote race-conscious research, and this paper describes ways to achieve this with a focus on the international Extracorporeal Life Support Organization (ELSO) registry. This article reviews ELSO registry publications that studied race with outcomes to consider whether research outputs align with race-conscious concepts and describe the direction of associations reported. Studies were identified via secondary analysis of a comprehensive scoping review on ECMO disparities. Of 32 multicenter publications, two (6%) studied race as the primary objective. Statistical analyses, confounder adjustment, and inclusive, antibiased language were inconsistently used. Only two (6%) papers explicitly discussed mechanistic drivers of inequity such as structural racism, and five (16%) discussed race variable limitations or acknowledged unmeasured confounders. Extracorporeal Life Support Organization registry publications demonstrated more adverse ECMO outcomes for underrepresented/minoritized populations than non-ELSO studies. With the objective to promote race-conscious ELSO registry research outputs, we provide a comprehensive understanding of race variable limitations, suggest reasoned retrospective analytic approaches, offer ways to interpret results that advance health equity, and recommend practice modifications for data collection.

Ethnic Disparities in Deep Sedation of Patients with Acute Respiratory Distress Syndrome in the United States: Secondary Analysis of a Multicenter Randomized Trial

Rationale: Patients identified as Hispanic, the largest minority group in the United States, are more likely to die from acute respiratory distress syndrome (ARDS) than non-Hispanic patients. Mechanisms to explain this disparity remain unidentified. However, Hispanic patients may be at risk of overexposure to deep sedation because of language differences between patients and clinicians, and deep sedation is associated with higher ARDS mortality.Objective: We examined associations between Hispanic ethnicity and exposure to deep sedation among patients with ARDS.Methods: A secondary analysis was conducted of patients enrolled in the control arm of a randomized trial of neuromuscular blockade for ARDS across 48 U.S. hospitals. Exposure to deep sedation was measured over the first 5 days that a patient was alive and received mechanical ventilation. Multilevel mixed-effects models were used to evaluate associations between Hispanic ethnicity and exposure to deep sedation, controlling for patient characteristics.Results: Patients identified as Hispanic had approximately five times the odds of deep sedation (odds ratio, 4.98; 95% confidence interval, 2.02-12.28; P < 0.0001) on a given day, compared with non-Hispanic White patients. Hospitals with at least one enrolled Hispanic patient kept all enrolled patients deeply sedated longer than hospitals without any enrolled Hispanic patients (85.8% of ventilator-days vs. 65.5%; P < 0.001).Conclusions: Hispanic patients are at higher risk of exposure to deep sedation than non-Hispanic White patients. There is an urgent need to understand and address disparities in sedation delivery.

The Role of Palliative Care Consultation in Withdrawal of Life-Sustaining Treatment among ICU Patients Receiving Veno-Venous Extracorporeal Membrane Oxygenation (VV-ECMO): A Retrospective Case-Control Study

Background: Extracorporeal membrane oxygenation (ECMO) has extended the survivability of critically ill patients beyond their unsupported prognosis and has widened the timeframe for making an informed decision about the goal of care. However, an extended time window for survival does not necessarily translate into a better outcome and the sustaining treatment is ultimately withdrawn in many patients. Emerging evidence has implicated the determining role of palliative care consult (PCC) in direction of the care that critically ill patients receive. Objective: To evaluate the impact of PCC in withdrawal of life-sustaining treatment (WOLST) among critically ill patients, who were placed on venovenous ECMO (VV-ECMO) at the intensive care unit (ICU) of a tertiary care hospital. Methods: In a retrospective observational study, electronic medical records of 750 patients admitted to the ICU of our hospital between January 1, 2015, and October 31, 2021, were reviewed. Data was collected for patients on VV-ECMO, for whom WOLST was withdrawn during the ICU stay. Clinical characteristics and the underlying reasons for WOLST were compared between those who received PCC (PCC group) and those who did not (non-PCC group). Results: A total of 95 patients were included in our analysis, 63 in the PCC group and 32 in the non-PCC group. The average age of the study population was 48.8 ± 12.6 years, and 64.2% were male. There was no statistically significant difference between the two groups in terms of demographics or clinical characteristics at the time of ICU admission. The average duration of ICU stay and VV-ECMO were 14.1 ± 19.9 days and 9.4 ± 16.6 days, respectively. The number of PCC visits was correlated with the length of ICU stay. The average duration of ICU stay (40.3 ± 33.2 days vs 27.8 ± 19.3 days, P = .05) and ECMO treatment (31.9 ± 27 days vs 18.6 ± 16.1 days, P = .01) were significantly longer in patients receiving PCC than those not receiving PCC. However, the frequency of life sustaining measures or the underlying reasons for WOLST did not significantly differ between the two groups (P > .05). Conclusion: Among ICU patients requiring ECMO support, longer duration of ICU stay and treatment with a higher number of life-sustaining measures seemed to be correlated with the number of PCC visits. The underlying reasons for WOLST seem not to be affected by PCC.

Kidney Increase Natriuresis but Not Glomerular Filtration Under Veno-venous ECMO, a Retrospective Study

PURPOSE

Acute kidney injury is a frequent complication of acute respiratory distress syndrome (ARDS). We aim to study the evolution of kidney function in patients presenting severe ARDS and requiring veno-venous extracorporeal membrane oxygenation (VV ECMO).

METHODS

We conducted a multicenter retrospective study, including adult patients requiring VV ECMO for ARDS. The primary outcome was the evolution of the serum creatinine level after VV ECMO initiation. Secondary outcomes were change in urine output, and urine biochemical parameters after VV ECMO initiation.

RESULTS

One hundred and two patients were included. VV ECMO was initiated after a median of 6 days of mechanical ventilation, mainly for ARDS caused by COVID-19 (73%). Serum creatinine level did not significantly differ after VV ECMO initiation (P = .20). VV ECMO was associated with a significant increase in daily urine output (+6.6 mL/kg/day, [3.8;9.3] P < .001), even after adjustment for potential confounding factors; with an increase in natriuresis. The increase in urine output under VV ECMO was associated with a reduced risk of receiving kidney replacement therapy (OR 0.4 [0.2;0.8], P = .026).

CONCLUSIONS

VV ECMO initiation in severe ARDS is associated with an increase in daily urine output and natriuresis, without change in glomerular filtration rate.

Successful management of temporary veno-venous extracorporeal membrane oxygenation for a pediatric lung transplant recipient with bronchiolitis obliterans syndrome awaiting lung re-transplantation: a case report

BACKGROUND

The use of extracorporeal membrane oxygenation (ECMO) as a bridge to lung transplantation is an uncommon strategy in Japan owing to the severe donor shortage and absence of urgent allocation policy. Moreover, the use of veno-venous (VV) ECMO for immunosuppressed patients is controversial; thus, applying ECMO to patients who await lung re-transplantation is challenging.

CASE PRESENTATION

A 16-year-old lung transplant recipient with grade 3 bronchiolitis obliterans syndrome was waitlisted for lung re-transplantation. Eleven months later, he fell into severe respiratory acidosis with hypercapnia, which were not resolved with mechanical ventilation. VV ECMO was introduced to minimize lung stress and strain. Tracheostomy was additionally performed on day 5 after the start of ECMO, and respiratory condition swiftly improved; hence, the weaning process from VV ECMO began on day 9. Rehabilitation became implementable, and bilateral re-lung transplantation was successfully performed 6 months after the ECMO treatment. No critical complication related to the precedent use of ECMO was noted.

CONCLUSIONS

VV ECMO can be a feasible treatment option even for lung transplant candidates awaiting re-transplantation for a prolonged period. Introduction of ECMO and tracheostomy in the early deterioration stage may be crucial to successful subsequent patient management.

Retrospective analysis of factors associated with outcome in veno-venous extra-corporeal membrane oxygenation

BACKGROUND

The outcome of Veno-Venous Extracorporeal Membrane Oxygenation (VV-ECMO) in acute respiratory failure may be influenced by patient-related factors, center expertise and modalities of mechanical ventilation (MV) during ECMO. We determined, in a medium-size ECMO center in Switzerland, possible factors associated with mortality during VV-ECMO for acute respiratory failure of various etiologies.

METHODS

We retrospectively analyzed all patients treated with VV-ECMO in our University Hospital from 2012 to 2019 (pre-COVID era). Demographic variables, severity scores, MV duration before ECMO, pre and on-ECMO arterial blood gases and respiratory variables were collected. The primary outcome was ICU mortality. Data were compared between survivors and non-survivors, and factors associated with mortality were assessed in univariate and multivariate analyses.

RESULTS

Fifty-one patients (33 ARDS, 18 non-ARDS) were included. ICU survival was 49% (ARDS, 39%; non-ARDS 67%). In univariate analyses, a higher driving pressure (DP) at 24h and 48h on ECMO (whole population), longer MV duration before ECMO and higher DP at 24h on ECMO (ARDS patients), were associated with mortality. In multivariate analyses, ECMO indication, higher DP at 24h on ECMO and, in ARDS, longer MV duration before ECMO, were independently associated with mortality.

CONCLUSIONS

DP on ECMO and longer MV duration before ECMO (in ARDS) are major, and potentially modifiable, factors influencing outcome during VV-ECMO.

Health Disparities in Extracorporeal Membrane Oxygenation Utilization and Outcomes: A Scoping Review and Methodologic Critique of the Literature

OBJECTIVES

To map the scope, methodological rigor, quality, and direction of associations between social determinants of health (SDoH) and extracorporeal membrane oxygenation (ECMO) utilization or outcomes.

DATA SOURCES

PubMed, Web of Science, Embase, and Cochrane Library databases were systematically searched for citations from January 2000 to January 2023, examining socioeconomic status (SES), race, ethnicity, hospital and ECMO program characteristics, transport, and geographic location (context) with utilization and outcomes (concept) in ECMO patients (population).

STUDY SELECTION

Methodology followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses scoping review extension. Two reviewers independently evaluated abstracts and full text of identified publications. Exclusion criteria included non-English, unavailable, less than 40 patients, and periprocedural or mixed mechanical support.

DATA EXTRACTION

Content analysis used a standardized data extraction tool and inductive thematic analysis for author-proposed mediators of disparities. Risk of bias was assessed using the Quality in Prognosis Studies tool.

DATA SYNTHESIS

Of 8,214 citations screened, 219 studies were identified. Primary analysis focuses on 148 (68%) including race/ethnicity/SES/payer variables including investigation of ECMO outcomes 114 (77%) and utilization 43 (29%). SDoH were the primary predictor in 15 (10%). Overall quality and methodologic rigor was poor with advanced statistics in 7%. Direction of associations between ECMO outcomes or utilization according to race, ethnicity, SES, or payer varied. In 38% adverse outcomes or lower use was reported in underrepresented, under-resourced or diverse populations, while improved outcomes or greater use were observed in these populations in 7%, and 55% had no statistically significant result. Only 26 studies (18%) discussed mechanistic drivers of disparities, primarily focusing on individual- and hospital-level rather than systemic/structural factors.

CONCLUSIONS

Associations between ECMO utilization and outcomes with SDoH are inconsistent, complicated by population heterogeneity and analytic shortcomings with limited consideration of systemic contributors. Findings and research gaps have implications for measuring, analyzing, and interpreting SDoH in ECMO research and healthcare.

Use of Recombinant Activated Factor VII in Bleeding Lung Transplant Patients Undergoing Perioperative ECMO Therapy

BACKGROUND

Hemostasis in critically ill patients represents a fragile balance between hypocoagulation and hypercoagulation, and is influenced by various factors. Perioperative use of extracorporeal membrane oxygenation (ECMO)-increasingly used in lung transplantation-further destabilizes this balance, not least due to systemic anticoagulation. In the case of massive hemorrhage, guidelines recommend considering recombinant activated Factor VII (rFVIIa) as an ultima ratio treatment only after several preconditions of hemostasis have been established. These conditions are calcium levels ≥ 0.9 mmol/L, fibrinogen levels ≥ 1.5 g/L, hematocrit ≥ 24%, platelet count ≥ 50 G/L, core body temperature ≥ 35 °C, and pH ≥ 7.2.

OBJECTIVES

This is the first study to examine the effect of rFVIIa on bleeding lung transplant patients undergoing ECMO therapy. The fulfillment of guideline-recommended preconditions prior to the administration of rFVIIa and its efficacy alongside the incidence of thromboembolic events were investigated.

METHODS

In a high-volume lung transplant center, all lung transplant recipients receiving rFVIIa during ECMO therapy between 2013 and 2020 were screened for the effect of rFVIIa on hemorrhage, fulfillment of recommended preconditions, and incidence of thromboembolic events.

RESULTS AND DISCUSSION

Of the 17 patients who received 50 doses of rFVIIa, bleeding ceased in four patients without surgical intervention. Only 14% of rFVIIa administrations resulted in hemorrhage control, whereas 71% of patients required revision surgery for bleeding control. Overall, 84% of all recommended preconditions were fulfilled; however, fulfillment was not associated with rFVIIa efficacy. The incidence of thromboembolic events within five days of rFVIIa administration was comparable to cohorts not receiving rFVIIa.

Routine whole-body CT identifies clinically significant findings in patients supported with veno-venous extracorporeal membrane oxygenation

AIM

To determine the yield of routine whole-body computed tomography (CT) following extracorporeal membrane oxygenation (ECMO) initiation and to assess the association of these findings with prognosis.

MATERIALS AND METHODS

One hundred and ninety-eight consecutive patients with acute respiratory failure admitted for ECMO support between January 2015 and December 2019 who underwent whole-body CT performed within 48 h of ECMO initiation were examined in this single-institution retrospective study. CT findings were divided into three categories: clinically significant findings that may affect immediate management strategy or short-term outcomes; findings not related to hospital stay or outcome but require further workup; and benign findings that do not require further investigation. Logistic regression analysis was used to assess the association of CT findings with 7- and 30-day survival.

RESULTS

Clinically significant findings were present in 147 (74%) patients, findings requiring further workup were found in 82 (41%) patients, and benign findings were identified in 180 (90%) of the patients. Patients with clinically significant neurological findings had an elevated risk of death at 7 days (odds ratio [OR] 3.58; 95% confidence interval [CI] 1.29; 9.93; p=0.01), but not 30 days. Increasing numbers of clinically significant findings were associated with greater odds of mortality at 7 days (OR 1.70; 95% CI 1.08; 2.67; p=0.02) and 30 days (OR 1.41; 95% CI 1.02; 1.96; p=0.04).

CONCLUSIONS

Imaging patients at the point of admission for VV-ECMO with CT frequently identified clinically significant abnormalities with prognostic implications of these. These findings provide support for the use of more routine CT at the point of treatment escalation with prospective studies now required.

Five critically ill pregnant women/parturients treated with extracorporeal membrane oxygenation

BACKGROUND

Maternal mortality has always been a major medical concern. Recently, the successful application of extracorporeal membrane oxygenation (ECMO) technology in the rescue of near-death patients has been reported.

CASE PRESENTATION

This study retrospectively analyzed 5 cases of critically ill pregnant women/parturients treated with ECMO for respiratory and circulatory failure in the Wuxi People's Hospital from 2018 to 2020. The mean age of the 5 cases was 30.2 years. Among them, Cases 1 and 5 were treated with Venoarterial (VA) ECMO. Case 1 was diagnosed with congenital heart disease, atrial septal defect, and severe pulmonary hypertension. VA ECMO was applied before cesarean section and was successfully removed after double lung transplantation, but the patient died 10 months after delivery from lung infection. While Case 5 was diagnosed with systemic lupus erythematosus, lupus nephritis, thrombotic vascular disease, HELLP syndrome, and cerebral hemorrhage. VA ECMO was applied 39 days after cesarean section, and the patient died 40 days after delivery due to multiple organ failure. Cases 3 and 4 were treated with Venovenous (VV) ECMO. Case 3 was diagnosed with refractory postpartum hemorrhage, and Case 4 was diagnosed with postpartum hypoglycemic coma, aspiration pneumonia, and shock. They were treated with VV ECMO after delivery, and all survived after successful evacuation. Another Case (Case 2) was diagnosed with postpartum pelvic infection, sepsis and septic shock, and was treated with VA ECMO at 15 days after delivery. The patient changed to VV ECMO at 30 days after delivery due to significant improvement in heart function and poor lung function, but eventually died of multiple organ failure. For the 5 cases, the mean duration of ECMO was 8.7 days, the mean duration of intensive care was 22.0 days, and the mean length of hospital stay was 57.6 days. As a result, 3 patients gradually returned to normal with significant improvement in ventilation and oxygenation after ECMO treatment.

CONCLUSIONS

ECMO technology can be used to treat some of the critical obstetric patients with respiratory and circulatory failure that is ineffective to conventional treatment, but it has no therapeutic effect on the primary disease.

Complications Associated With Venovenous Extracorporeal Membrane Oxygenation-What Can Go Wrong?

OBJECTIVES

Despite increasing use and promising outcomes, venovenous extracorporeal membrane oxygenation (V-V ECMO) introduces the risk of a number of complications across the spectrum of ECMO care. This narrative review describes the variety of short- and long-term complications that can occur during treatment with ECMO and how patient selection and management decisions may influence the risk of these complications.

DATA SOURCES

English language articles were identified in PubMed using phrases related to V-V ECMO, acute respiratory distress syndrome, severe respiratory failure, and complications.

STUDY SELECTION

Original research, review articles, commentaries, and published guidelines from the Extracorporeal Life support Organization were considered.

DATA EXTRACTION

Data from relevant literature were identified, reviewed, and integrated into a concise narrative review.

DATA SYNTHESIS

Selecting patients for V-V ECMO exposes the patient to a number of complications. Adequate knowledge of these risks is needed to weigh them against the anticipated benefit of treatment. Timing of ECMO initiation and transfer to centers capable of providing ECMO affect patient outcomes. Choosing a configuration that insufficiently addresses the patient's physiologic deficit leads to consequences of inadequate physiologic support. Suboptimal mechanical ventilator management during ECMO may lead to worsening lung injury, delayed lung recovery, or ventilator-associated pneumonia. Premature decannulation from ECMO as lungs recover can lead to clinical worsening, and delayed decannulation can prolong exposure to complications unnecessarily. Short-term complications include bleeding, thrombosis, and hemolysis, renal and neurologic injury, concomitant infections, and technical and mechanical problems. Long-term complications reflect the physical, functional, and neurologic sequelae of critical illness. ECMO can introduce ethical and emotional challenges, particularly when bridging strategies fail.

CONCLUSIONS

V-V ECMO is associated with a number of complications. ECMO selection, timing of initiation, and management decisions impact the presence and severity of these potential harms.

Be Patient: Prolonged Extracorporeal Membrane Oxygenation Support Including Full System Switch With Favorable Outcome

Despite tremendous advances in treatment, acute respiratory distress syndrome (ARDS) remains a disease with high mortality (42-48%). Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is often used as a last treatment option, which poses complex problems for the treatment team, especially with prolonged ECMO support. We report an interesting case of a 40-year-old female patient who developed influenza pneumonia leading to ARDS and subsequently requiring ECMO. Due to severe clotting complications, a prolonged ECMO run time with numerous filter changes was required. After a total of 56 days of ECMO therapy, the patient was successfully weaned. Fortunately, further in the course of treatment, complete recovery with restitutio ad integrum was achieved. A distinguishing feature of this case report is the description of a complete ECMO system change and the concurrent use of two ECMO systems for the same patient. Additionally, we provide data on the patient's current health-related quality of life as measured using the World Health Organization Disability Assessment Schedule 2.0.

Extracorporeal Support for Acute Respiratory Distress Syndrome in Adults

Extracorporeal Support for ARDS in AdultsThere is a subset of patients who develop severe ARDS for whom supportive care with mechanical ventilation is insufficient or possibly injurious. The use of ECMO as an adjunct to treat these patients is reviewed.

Predictors of survival for pediatric extracorporeal cardiopulmonary resuscitation: A systematic review and meta-analysis

BACKGROUND

The use of extracorporeal cardiopulmonary resuscitation (ECPR) has improved survival in patients with cardiac arrest; however, factors predicting survival remain poorly characterized. A systematic review and meta-analysis was conducted to examine the predictors of survival of ECPR in pediatric patients.

METHODS

We searched EMBASE, PubMed, SCOPUS, and the Cochrane Library from 2010 to 2021 for pediatric ECPR studies comparing survivors and non-survivors. Thirty outcomes were analyzed and classified into 5 categories: demographics, pre-ECPR laboratory measurements, pre-ECPR co-morbidities, intra-ECPR characteristics, and post-ECPR complications.

RESULTS

Thirty studies (n = 3794) were included. Pooled survival to hospital discharge (SHD) was 44% (95% CI: 40%-47%, I2 = 67%). Significant predictors of survival for pediatric ECPR include the pre-ECPR lab measurements of PaO2, pH, lactate, PaCO2, and creatinine, pre-ECPR comorbidities of single ventricle (SV) physiology, renal failure, sepsis, ECPR characteristics of extracorporeal membrane oxygenation (ECMO) duration, ECMO flow rate at 24 hours, cardiopulmonary resuscitation (CPR) duration, shockable rhythm, intra-ECPR neurological complications, and post-ECPR complications of pulmonary hemorrhage, renal failure, and sepsis.

CONCLUSION

Prior to ECPR initiation, increased CPR duration and lactate levels had among the highest associations with mortality, followed by pH. After ECPR initiation, pulmonary hemorrhage and neurological complications were most predictive for survival. Clinicians should focus on these factors to better inform potential prognosis of patients, advise appropriate patient selection, and improve ECPR program effectiveness.

Intracranial haemorrhage in adult patients on venoarterial extracorporeal membrane oxygenation

AIMS

Intracranial haemorrhage (ICH) is one of the most serious complications of adult patients treated with venoarterial extracorporeal membrane oxygenation (VA-ECMO) and is associated with increased morbidity and mortality. However, the prevalence and risk factors of ICH in this cohort are still insufficiently understood. We hypothesized that a considerable proportion of patients undergoing VA-ECMO support suffer from ICH and that specific risk factors are associated with the occurrence of ICH. Therefore, the purpose of this study was to further investigate the prevalence and associated mortality as well as to identify risk factors for ICH in VA-ECMO patients.

METHODS AND RESULTS

We conducted a retrospective multicentre study including adult patients (≥18 years) treated with VA-ECMO in cardiac intensive care units (ICUs) at five German clinical sites between January 2016 and March 2020, excluding patients with ICH upon admission. Differences in baseline characteristics and clinical outcome between VA-ECMO patients with and without ICH were analysed and risk factors for ICH were identified. Among the 598 patients included, 70/598 (12%) developed ICH during VA-ECMO treatment. In-hospital mortality in patients with ICH was 57/70 (81%) and 1-month mortality 60/70 (86%), compared to 332/528 (63%) (P = 0.002) and 340/528 (64%) (P < 0.001), respectively, in patients without ICH. Intracranial haemorrhage was positively associated with diabetes mellitus [odds ratio (OR) 2, 95% confidence interval (CI) 1.11-3.56; P = 0.020] and lactate (per mmol/L) (OR 1.06, 95% CI 1.01-1.11; P = 0.020), and negatively associated with platelet count (per 100 G/L) (OR 0.32, 95% CI 0.15-0.59; P = 0.001) and fibrinogen (per 100 mg/dL) (OR 0.64, 95% CI 0.49-0.83; P < 0.001).

CONCLUSION

Intracranial haemorrhage was associated with a significantly higher mortality rate. Diabetes mellitus and lactate were positively, platelet count, and fibrinogen level negatively associated with the occurrence of ICH. Thus, platelet count and fibrinogen level were revealed as potentially modifiable, independent risk factors for ICH. The findings address an area with limited data, provide information about risk factors and the epidemiology of ICH, and may be a starting point for further investigations to develop effective strategies to prevent and treat ICH.

Managing pulmonary arterial hypertension: how to select and facilitate successful transplantation

PURPOSE OF REVIEW

Despite improvements in available medical therapies, pulmonary arterial hypertension (PAH) remains a progressive, ultimately fatal disorder. Lung transplantation is a viable treatment option for PAH patients with advanced disease.

RECENT FINDINGS

Recent guidelines from the International Society of Heart and Lung Transplantation (ISHLT) have updated recommendations regarding time of referral and listing for lung transplantation in PAH. The new guidelines emphasize earlier referral for transplant evaluation to ensure adequate time for proper evaluation and listing. They also incorporate objective risk stratification criteria to assist in decision-making regarding timing of referral and listing. With regards to the transplant procedure, bilateral lung transplantation has largely supplanted heart-lung transplantation as the procedure of choice for transplantation for advanced PAH. Exceptions to this include patients with PAH because of congenital heart disease and those with concurrent LV dysfunction. Use of mechanical support via venoarterial ECMO initiated before transplantation and continued into the early postoperative period is emerging as a standard of care and may help to reduce early posttransplant mortality in this population. There has been increased recognition of the importance of WHO Group 3 pulmonary hypertension. Many of the lessons learned from PAH may be applied when transplanting patients with severe WHO Group 3 pulmonary hypertension.

SUMMARY

Patients with PAH present unique challenges with regards to transplantation that require a therapeutic approach distinct from other lung disorders. Lung transplantations for PAH are high-risk endeavors best performed at centers with expertise in management of both PAH and extracorporeal support.

Risk Factors and Outcomes for Patients with Bleeding Complications Receiving Extracorporeal Membrane Oxygenation: An Analysis of the Chinese Extracorporeal Life Support Registry

OBJECTIVE

Bleeding is a severe complication of patients supported with extracorporeal membrane oxygenation (ECMO). This study aimed to analyze the occurrence, risk factors, and clinical outcomes of patients on ECMO with bleeding complications.

METHODS

ECMO cases reported to the multicenter ECMO registry database of the Chinese Society of Extracorporeal Life Support (CSECLS) from January 2017 to December 2020 were enrolled. General information, ECMO indications, application, complications, and patient outcomes were collected and analyzed.

RESULTS

A total of 6541 ECMO patients from 112 centers were enrolled. Overall, 1185 patients (18.1%) presented with one of the following bleeding complications, including 82 cases (1.3%) with severe bleeding during ECMO catheterization, 462 cases (7.1%) with bleeding at the ECMO cannulation site, 200 cases (3.5%) with bleeding at the surgical site, 180 cases (2.8%) with cerebral hemorrhage, 99 cases (1.5%) with pulmonary hemorrhage, 200 cases (3.5%) with gastrointestinal hemorrhage, 82 cases (1.3%) with ECMO withdrawal, and 118 (1.8%) deaths due to severe bleeding. Extracorporeal cardiopulmonary resuscitation (ECPR) patients had the highest incidence of bleeding complications (22.4%), followed by those on circulatory support (18.7%) and respiratory support (15.4%) (p<0.001). Multivariate analysis showed that pediatric patients (odds ratio [OR] 1.509, p<0.001), patients receiving renal replacement therapy (OR 1.932, p<0.001), and patients receiving central ECMO cannulation (OR 3.023, p<0.001) were independent risk factors for all bleeding complications, while peripheral cannulation (OR 0.712, p<0.001) was an independent protective factor. Patients with any bleeding complication had significantly higher in-hospital mortality than patients without (61.9% vs. 46.3%, p<0.001).

CONCLUSION

Up to 18.1% of ECMO patients in the CSECLS registry experienced bleeding complications, which was associated with higher in-hospital mortality, especially in patients who received ECPR, patients on circulatory support, and pediatric patients, which should arouse the attention of clinicians.

TPMS-based membrane lung with locally-modified permeabilities for optimal flow distribution

Membrane lungs consist of thousands of hollow fiber membranes packed together as a bundle. The devices often suffer from complications because of non-uniform flow through the membrane bundle, including regions of both excessively high flow and stagnant flow. Here, we present a proof-of-concept design for a membrane lung containing a membrane module based on triply periodic minimal surfaces (TPMS). By warping the original TPMS geometries, the local permeability within any region of the module could be raised or lowered, allowing for the tailoring of the blood flow distribution through the device. By creating an iterative optimization scheme for determining the distribution of streamwise permeability inside a computational porous domain, the desired form of a lattice of TPMS elements was determined via simulation. This desired form was translated into a computer-aided design (CAD) model for a prototype device. The device was then produced via additive manufacturing in order to test the novel design against an industry-standard predicate device. Flow distribution was verifiably homogenized and residence time reduced, promising a more efficient performance and increased resistance to thrombosis. This work shows the promising extent to which TPMS can serve as a new building block for exchange processes in medical devices.

Fracture of dual lumen cannula leading to cerebrovascular accident in a patient supported with ECMO

Extended duration extracorporeal membrane oxygenation (ECMO), using dual-lumen cannulas, is being used with increased frequency to support patients, including those with COVID-19; both as a bridge to transplant and lung recovery. During such an extended duration of support, there are several factors that might lead to the attrition of the physical structure of the ECMO cannulas, predisposing them to the risk of fracture. Although rare, fracture of the ECMO cannula can be a potentially lethal event. Here, we present a case where fracture of a dual lumen cannula during veno-venous (VV) ECMO support resulted in a cerebrovascular accident. We discuss the potential contributing factors and suggest steps to mitigate the risks for such a complication.

Duration of invasive mechanical ventilation prior to extracorporeal membrane oxygenation is not associated with survival in acute respiratory distress syndrome caused by coronavirus disease 2019

Background

Duration of invasive mechanical ventilation (IMV) prior to extracorporeal membrane oxygenation (ECMO) affects outcome in acute respiratory distress syndrome (ARDS). In coronavirus disease 2019 (COVID-19) related ARDS, the role of pre-ECMO IMV duration is unclear. This single-centre, retrospective study included critically ill adults treated with ECMO due to severe COVID-19-related ARDS between 01/2020 and 05/2021. The primary objective was to determine whether duration of IMV prior to ECMO cannulation influenced ICU mortality.

Results

During the study period, 101 patients (mean age 56 [SD ± 10] years; 70 [69%] men; median RESP score 2 [IQR 1–4]) were treated with ECMO for COVID-19. Sixty patients (59%) survived to ICU discharge. Median ICU length of stay was 31 [IQR 20.7–51] days, median ECMO duration was 16.4 [IQR 8.7–27.7] days, and median time from intubation to ECMO start was 7.7 [IQR 3.6–12.5] days. Fifty-three (52%) patients had a pre-ECMO IMV duration of > 7 days. Pre-ECMO IMV duration had no effect on survival (p = 0.95). No significant difference in survival was found when patients with a pre-ECMO IMV duration of < 7 days (< 10 days) were compared to ≥ 7 days (≥ 10 days) (p = 0.59 and p = 1.0).

Conclusions

The role of prolonged pre-ECMO IMV duration as a contraindication for ECMO in patients with COVID-19-related ARDS should be scrutinised. Evaluation for ECMO should be assessed on an individual and patient-centred basis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13613-022-00980-3.

Extracorporeal Membrane Oxygenation in Immunocompromised Patients With Acute Respiratory Distress Syndrome-A Retrospective Cohort Study

Objective: Although the negative impact of immunosuppression on survival in patients with acute respiratory distress syndrome (ARDS) treated by extracorporeal membrane oxygenation (ECMO) is well known, short-term outcomes such as successful weaning rate from ECMO and subgroups benefit most from ECMO remain to be determined. The aims of this study were (1) to identify the association between immunocompromised status and weaning from ECMO in patients of ARDS, and (2) to identify subgroups of immunocompromised patients who may benefit from ECMO.

Methods: This retrospective cohort study enrolled patients who received ECMO for ARDS from 2010 to 2020. Immunocompromised status was defined as having a hematological malignancy, active solid tumor, solid organ transplant, or autoimmune disease.

Results: This study enrolled 256 ARDS patients who received ECMO, of whom 68 were immunocompromised. The multivariable analysis showed that immunocompromised status was not independently associated with failure to wean from ECMO. In addition, the patients with an autoimmune disease (14/24, 58.3%) and organ transplantation (3/3, 100%) had a numerically higher weaning rate from ECMO than other immunocompromised patients. For causes of ARDS, most patients with pulmonary hemorrhage (6/8, 75%) and aspiration (5/9, 55.6%) could be weaned from ECMO, compared to only a few of the patients with interstitial lung disease (2/9, 22.2%) and sepsis (1/4, 25%).

Conclusions: Immunocompromised status was not an independent risk factor of failure to wean from ECMO in patients with ARDS. For patients with pulmonary hemorrhage and aspiration-related ARDS, ECMO may be beneficial as bridge therapy.

Extracorporeal Membrane Oxygenation Support for Influenza A: Retrospective Review of the Extracorporeal Life Support Organization Registry Comparing H1N1 With Other Subtypes

Supplemental Digital Content is available in the text.

OBJECTIVES:

Although there is a substantial published experience of extracorporeal membrane oxygenation during the H1N1 pandemic, less is known about the use of extracorporeal membrane oxygenation in patients with other subtypes of the influenza A virus. We hypothesized that the severity of illness and survival of patients supported with extracorporeal membrane oxygenation would differ for those with H1N1 influenza A compared with other subtypes of influenza A.

DESIGN, SETTING, PATIENTS:

Retrospective study of extracorporeal membrane oxygenation–supported adults (> 18 yr) with influenza A viral infection reported to the Extracorporeal Life Support Organization Registry between 2009 and 2019. We describe the frequency and compare characteristics and factors associated with in-hospital survival using a least absolute shrinkage and selection operator regression analysis.

MAIN OUTCOMES AND MEASURES:

Of 2,461 patients supported with extracorporeal membrane oxygenation for influenza A, 445 had H1N1, and 2,004 had other subtypes of influenza A. H1N1 was the predominant subtype between 2009 and 2011. H1N1 patients were younger, with more severe illness at extracorporeal membrane oxygenation cannulation and higher reported extracorporeal membrane oxygenation complications than those with other influenza A subtypes. Patient characteristics including younger age and higher weight and patient management characteristics including longer ventilation duration before extracorporeal membrane oxygenation were associated with worse survival. Extracorporeal membrane oxygenation complications were associated with reduced survival. There was no difference in survival to hospital discharge according to influenza subtype after adjusting for other characteristics.

CONCLUSIONS:

Patients supported with extracorporeal membrane oxygenation for H1N1 were younger, with more severe illness than those supported for other influenza A subtypes. Survival to hospital discharge was associated with patient characteristics, management characteristics, and extracorporeal membrane oxygenation complications but was not impacted by the specific influenza A subtype.

ECMO use in Germany: An analysis of 29,929 ECMO runs

Background

Extracorporeal Membrane Oxygenation (ECMO) use is increasing despite limited evidence. The aim of this study was to demonstrate heterogeneity of ECMO use and its association with hospital size and annual frequency in Germany.

Methods

This is a database analysis of all ECMO cases in Germany from 2010 to 2016 using the German Diagnosis Related Groups (DRG) coding system for ECMO.

Results

During the study period, 510 hospitals performed 29,929 ECMO runs (12,572 vvECMO, 11,504 vaECMO, 1993 pECLA) with an increase over time. Mortality ranged between 58% and 66% for vaECMO cases and 66% and 53% for vvECMO cases. 304 (61%) hospitals performed only one ECMO per year. 78%% of all ECMO runs were performed in centres with more than 20 cases per year and more than half of all ECMO runs were performed in hospitals with >1.000 beds. Mortality for vv and vaECMO was highest in very small hospitals (< 200 beds; 70%; 74%) and very large hospitals (>1000 beds; 60%; 62%).

Conclusions

Use of ECMO is still increasing and a substantial proportion of hospitals performs very few ECMO runs. Small hospitals had a significantly higher mortality, but dependence on hospital size and ECMO mortality was irregular.

Risk Factors of Mortality for Patients Receiving Venovenous Extracorporeal Membrane Oxygenation for COVID-19 Acute Respiratory Distress Syndrome

Background: Venovenous extracorporeal membrane oxygenation (VV-ECMO) for select adults with severe acute respiratory distress syndrome (ARDS) cause by coronavirus disease 2019 (COVID-19) infection is a guideline-supported therapy with associated hospital survival of 62%-74%, similar to expected survival with VV-ECMO for other indications. However, ECMO is a resource-heavy intervention, and these patients often require long ECMO runs and prolonged intensive care unit (ICU) care. Identifying factors associated with mortality in VV-ECMO patients with COVID-19 infection can inform the evaluation of ECMO candidates as well as prognostication for those patients on prolonged VV-ECMO. Patients and Methods: This was a retrospective cohort study that included all patients who received either VV- or venoarteriovenous (VAV)-ECMO at one of four ECMO Centers of Excellence in the state of Minnesota between March 1, 2020 and November 1, 2020. The primary outcome was 60-day survival. Secondary outcomes were hospital complications, infectious complications, and complications from ECMO. Results: There were 46 patients who met criteria during this study period and 30 survived to 60-day follow-up (65.2%). Prior to cannulation, older patient age (55.5 in non-survivors vs. 49.1 years in survivors; p = 0.03), lower P/F ratio (62.1 vs. 76.2; p = 0.04), and higher sequential organ failure assessment (SOFA) score (8.1 vs. 6.6; p = 0.02) were identified as risk factors for mortality. After ECMO cannulation, increased mortality was associated with increased number of antibiotic days (25.9 vs. 14.5; p = 0.04), increased number of transfusions (23.9 vs. 9.9; p = 0.03), elevated white blood cell (WBC) count at post-ECMO days one through three, elevated D-dimer at post-ECMO day 21-27, and decreased platelet count from post-ECMO days 14 and onward using univariable analysis. Conclusions: Multiple markers of infection including leukocytosis, thrombocytopenia, and increased antibiotic days are associated with increased mortality in patients placed on VV-ECMO for COVID-19 infection and subsequent ARDS. Knowledge of these factors may assist with determining appropriate candidates for this limited resource as well as direct goals of care in prolonged ECMO courses.

Quality of life and functional status of patients treated with venovenous extracorporeal membrane oxygenation at 6 months

PURPOSE

Quality of life (QoL) outcomes of patients treated with extracorporeal membrane oxygenation (ECMO) for acute respiratory distress syndrome (ARDS) have been conflicting. This study reports on QoL outcomes for a broad group of ARDS patients managed with up-to-date treatment modalities.

METHODS

We prospectively recruited patients at a quaternary hospital in the United Kingdom from 2013 to 2015 who were treated with ECMO for ARDS. We evaluated their pulmonary function and QoL at 6-months after admission using three QoL instruments: EuroQoL 5D (EQ-5), HADS, and PTSS-14.

RESULTS

Forty-three patients included in the analysis had near-normal pulmonary function at 6 months. HADS showed moderate-to-severe anxiety and depression in 32% and 11% of patients, respectively. PTSS-14 showed 29% had signs of post-traumatic stress disorder. EQ-5D showed that 67% of patients had difficulty returning to usual activities, 74% suffered some pain, none reported severe problems and 77% were able to return to work. No clinical or demographic variables were associated with poor 6-month QoL.

CONCLUSIONS

Patients with ARDS treated with ECMO generally had good QoL outcomes, similar to outcomes reported for patients managed without ECMO. With respect to QoL, VV-EMCO represents a valid treatment modality for patients with refractory ARDS.

Contraindications to the Initiation of Veno-Venous ECMO for Severe Acute Respiratory Failure in Adults: A Systematic Review and Practical Approach Based on the Current Literature

(1) Background: Extracorporeal membrane oxygenation (ECMO) is increasingly used for acute respiratory failure with few absolute but many relative contraindications. The provider in charge often has a difficult time weighing indications and contraindications to anticipate if the patient will benefit from this treatment, a decision that often decides life and death for the patient. To assist in this process in coming to a good evidence-based decision, we reviewed the available literature. (2) Methods: We performed a systematic review through a literature search of the MEDLINE database of former and current absolute and relative contraindications to the initiation of ECMO treatment. (3) Results: The following relative and absolute contraindications were identified in the literature: absolute-refusal of the use of extracorporeal techniques by the patient, advanced stage of cancer, fatal intracerebral hemorrhage/cerebral herniation/intractable intracranial hypertension, irreversible destruction of the lung parenchyma without the possibility of transplantation, and contraindications to lung transplantation; relative-advanced age, immunosuppressed patients/pharmacological immunosuppression, injurious ventilator settings > 7 days, right-heart failure, hematologic malignancies, especially bone marrow transplantation and graft-versus-host disease, SAPS II score ≥ 60 points, SOFA score > 12 points, PRESERVE score ≥ 5 points, RESP score ≤ -2 points, PRESET score ≥ 6 points, and "do not attempt resuscitation" order (DN(A)R status). (4) Conclusions: We provide a simple-to-follow algorithm that incorporates absolute and relative contraindications to the initiation of ECMO treatment. This algorithm attempts to weigh pros and cons regarding the benefit for an individual patient and hopefully assists caregivers to make better, informed decisions.

Clinical outcomes of immunocompromised patients on extracorporeal membrane oxygenation support for severe acute respiratory failure

OBJECTIVES

There are limited data regarding extracorporeal membrane oxygenation (ECMO) support in immunocompromised patients, despite an increase in ECMO use in patients with respiratory failure. The aim of this study was to investigate the clinical characteristics and outcomes of immunocompromised patients requiring ECMO support for severe acute respiratory failure.

METHODS

Between January 2012 and December 2015, all consecutive adult patients with severe acute respiratory failure who underwent ECMO for respiratory support at 16 tertiary or university-affiliated hospitals in South Korea were enrolled retrospectively. The patients were divided into 2 groups based on the immunocompromised status at the time of ECMO initiation. In-hospital and 6-month mortalities were compared between the 2 groups. In addition, association of immunocompromised status with 6-month mortality was evaluated with logistic regression analysis.

RESULTS

Among 461 patients, 118 (25.6%) were immunocompromised. Immunocompromised patients were younger and had lower haemoglobin and platelet counts than immunocompetent patients. Ventilatory parameters and the use of adjunctive/rescue therapies were similar between the 2 groups, but prone positioning was more commonly used in immunocompetent patients. Successful weaning rates from ECMO (46.6% vs 58.9%; P = 0.021) was lower and hospital mortality (66.1% vs 59.8%; P = 0.22) was higher in immunocompromised patients. In addition, immunocompromised status was associated with higher 6-month mortality (74.6% vs 64.7%, adjusted odds ratio 2.10, 95% confidence interval 1.02-4.35; P = 0.045).

CONCLUSIONS

Immunocompromised patients treated with ECMO support for severe acute respiratory failure had poorer short- and long-term prognoses than did immunocompetent patients.

Predictors of Mortality in Patients Treated with Veno-Arterial ECMO for Cardiogenic Shock Complicating Acute Myocardial Infarction: a Systematic Review and Meta-Analysis

BACKGROUND

Mortality for patients on veno-arterial extracorporeal membrane oxygenation (VA-ECMO) for cardiogenic shock (CS) complicating acute myocardial infarction (AMI) remains high. This meta-analysis aims to identify factors that predict higher risk of mortality after VA-ECMO for AMI.

METHODS

We meta-analyzed mortality after VA-ECMO for CS complicating AMI and the effect of factors from systematically selected studies published after 2009.

RESULTS

72 studies (10,276 patients) were included with a pooled mortality estimate of 58 %. With high confidence in estimates, failure to achieve TIMI III flow and left main culprit were identified as factors associated with higher mortality. With low-moderate confidence, older age, high BMI, renal dysfunction, increasing lactate, prothrombin activity < 50%, VA-ECMO implantation after revascularization, and non-shockable ventricular arrythmias were identified as factors associated with mortality.

CONCLUSION

These results provide clinicians with a framework for selecting patients for VA-ECMO for CS complicating AMI.

Joint Society of Critical Care Medicine-Extracorporeal Life Support Organization Task Force Position Paper on the Role of the Intensivist in the Initiation and Management of Extracorporeal Membrane Oxygenation

OBJECTIVES

To define the role of the intensivist in the initiation and management of patients on extracorporeal membrane oxygenation.

DESIGN

Retrospective review of the literature and expert consensus.

SETTING

Series of in-person meetings, conference calls, and emails from January 2018 to March 2019.

SUBJECTS

A multidisciplinary, expert Task Force was appointed and assembled by the Society of Critical Care Medicine and the Extracorporeal Life Support Organization. Experts were identified by their respective societies based on reputation, experience, and contribution to the field.

INTERVENTIONS

A MEDLINE search was performed and all members of the Task Force reviewed relevant references, summarizing high-quality evidence when available. Consensus was obtained using a modified Delphi process, with agreement determined by voting using the RAND/UCLA scale, with score ranging from 1 to 9.

MEASUREMENTS AND MAIN RESULTS

The Task Force developed 18 strong and five weak recommendations in five topic areas of extracorporeal membrane oxygenation initiation and management. These recommendations were organized into five areas related to the care of patients on extracorporeal membrane oxygenation: patient selection, management, mitigation of complications, coordination of multidisciplinary care, and communication with surrogate decision-makers. A common theme of the recommendations is extracorporeal membrane oxygenation is best performed by a multidisciplinary team, which intensivists are positioned to engage and lead.

CONCLUSIONS

The role of the intensivist in the care of patients on extracorporeal membrane oxygenation continues to evolve and grow, especially when knowledge and familiarity of the issues surrounding extracorporeal membrane oxygenation selection, cannulation, and management are applied.

Outcomes of extracorporeal membrane oxygenation in adults with active hematologic and nonhematologic malignancy

Although the number of cancer patients admitted to the intensive care unit is increasing, the data on the use of extracorporeal membrane oxygenation in patients with malignancy are limited. We applied extracorporeal membrane oxygenation to carefully selected patients with active hematologic malignancy or nonhematologic malignancy who experienced respiratory or cardiac failure despite maximal conventional therapy. Patients with active malignancy who underwent extracorporeal membrane oxygenation in our institution between January 2012 and December 2016 were included in this study. The primary outcome of this study was defined as survival to hospital discharge. We also investigated the factors associated with survival to hospital discharge. There were 30 (30.6%) and 68 (69.4%) patients in the hematologic malignancy group and the nonhematologic malignancy group, respectively. Patients in the hematologic malignancy group were younger, more neutropenic, more hypotensive, had a lower Charlson Comorbidity Index, higher sequential organ failure assessment score, and lower platelet count than those in the nonhematologic malignancy group. Forty-six (46.9%) patients were successfully weaned off extracorporeal membrane oxygenation, and 30 (30.6%) patients survived until hospital discharge. Hospital survival rate and survival status 6 months after hospital discharge were significantly lower in patients with hematologic malignancy than in those with nonhematologic malignancy (13.3% vs. 38.2%, P = .026 and 3.3% vs. 26.5%, P = .017, respectively). Multivariate analysis identified an active hematologic malignancy, older age, acidosis, thrombocytopenia, high vasoactive-inotrope score, and respiratory failure as the risk factors for in-hospital death. Patients with hematologic malignancy requiring extracorporeal membrane oxygenation support had significantly lower rates of hospital survival and 6-month survival after discharge than patients with nonhematologic malignancy. Therefore, extracorporeal membrane oxygenation for treating cardiac or respiratory failure should only be considered in highly selected patients with hematologic malignancy.

Improving Hemocompatibility: How Can Smart Surfaces Direct Blood To Fight against Thrombi

Nature utilizes endothelium as a blood interface that perfectly controls hemostasis, preventing the uncontrolled formation of thrombi. The management of positive and negative feedback that finely tunes thrombosis and fibrinolysis is essential for human life, especially for patients who undergo extracorporeal circulation (ECC) after a severe respiratory or cardiac failure. The exposure of blood to a surface different from healthy endothelium inevitably initiates coagulation, drastically increasing the mortality rate by thromboembolic complications. In the present study, an ultrathin antifouling fibrinolytic coating capable of disintegrating thrombi in a self-regulated manner is reported. The coating system is composed of a polymer brush layer that can prevent any unspecific interaction with blood. The brushes are functionalized with a tissue plasminogen activator (tPA) to establish localized fibrinolysis that solely and exclusively is active when it is required. This interactive switching between the dormant and active state is realized through an amplification mechanism that increases (positive feedback) or restores (negative feedback) the activity of tPA depending on whether a thrombus is detected and captured or not. Thus, only a low surface density of tPA is necessary to lyse real thrombi. Our work demonstrates the first report of a coating that self-regulates its fibrinolytic activity depending on the conditions of blood.

Extracorporeal Membrane Oxygenation Therapy for Critically Ill Coronavirus Disease 2019 Patients in Wuhan, China: A Retrospective Multicenter Cohort Study

Currently, little in-depth evidence is known about the application of extracorporeal membrane oxygenation (ECMO) therapy in coronavirus disease 2019 (COVID-19) patients. This retrospective multicenter cohort study included patients with COVID-19 at 7 designated hospitals in Wuhan, China. The patients were followed up until June 30, 2020. Univariate and multivariate logistic regression analyses were performed to identify the risk factors associated with unsuccessful ECMO weaning. Propensity score matching was used to match patients who received veno-venous ECMO with those who received invasive mechanical ventilation (IMV)-only therapy. Of 88 patients receiving ECMO therapy, 27 and 61 patients were and were not successfully weaned from ECMO, respectively. Additionally, 15, 15, and 65 patients were further weaned from IMV, discharged from hospital, or died during hospitalization, respectively. In the multivariate logistic regression analysis, a lymphocyte count ≤0.5×10⁹/L and D-dimer concentration >4× the upper limit of normal level at ICU admission, a peak PaCO₂ >60 mmHg at 24 h before ECMO initiation, and no tracheotomy performed during the ICU stay were independently associated with lower odds of ECMO weaning. In the propensity score-matched analysis, a mixed-effect Cox model detected a lower hazard ratio for 120-day all-cause mortality after ICU admission during hospitalization in the ECMO group. The presence of lymphocytopenia, higher D-dimer concentrations at ICU admission and hypercapnia before ECMO initiation could help to identify patients with a poor prognosis. Tracheotomy could facilitate weaning from ECMO. ECMO relative to IMV-only therapy was associated with improved outcomes in critically ill COVID-19 patients.

Use of therapeutic plasma exchange in heparin-induced thrombocytopenia: A population-based study

BACKGROUND

Heparin-induced thrombocytopenia (HIT) is characterized by anti-heparin/platelet factor 4 immune complexes, which are removed by therapeutic plasma exchange (TPE). Our main objective was to study TPE outcomes in HIT using a large administrative claims database.

STUDY DESIGN AND METHODS

We used the National Inpatient Sample (NIS) to identify hospital discharges of adult patients (≥18) with a primary or secondary diagnosis of HIT. Cases were classified into two groups based on TPE use. The primary outcome was in-hospital mortality. Secondary outcomes were thrombotic events, major bleeding, hospital length of stay (LOS), and charges. Multivariable regression analysis, controlling for age and medical comorbidities, was used to examine the association of TPE with study outcomes.

RESULTS

A HIT diagnosis was made in 22 165 discharges, of which 90 (0.4%) received TPE. Corresponding national estimates are 106 435 and 439, respectively. TPE was not associated with decreased in-hospital mortality (OR = 1.72; 95%CI: 0.93-3.17, P = .085). However, TPE was associated with a higher likelihood of major bleeding (OR = 2.35; 95%CI: 1.40-3.68, P = .0009), primarily driven by gastrointestinal bleeding (OR = 2.21; 95%CI: 1.17-4.17, P = .015). TPE was also associated with higher hospital LOS (20.5 vs 10 day, P < .0001) and charges (USD 211181 vs USD 81654, P < .0001).

CONCLUSION

TPE's association with increased bleeding and a prolonged hospital course indicates that it is being used in HIT cases with a severe clinical phenotype. Future studies are needed to better characterize the HIT phenotype that will most benefit from TPE.

Time-Course of Physiologic Variables During Extracorporeal Membrane Oxygenation and Outcome of Severe Acute Respiratory Distress Syndrome

In patients undergoing extracorporeal membrane oxygenation (ECMO) for acute respiratory distress syndrome (ARDS), it is unknown which clinical physiologic variables should be monitored to follow the evolution of lung injury and extrapulmonary organ dysfunction and to differentiate patients according to their course. We analyzed the time-course of prospectively collected clinical physiologic variables in 83 consecutive ARDS patients undergoing ECMO at a single referral center. Selected variables-including ventilator settings, respiratory system compliance, intrapulmonary shunt, arterial blood gases, central hemodynamics, and sequential organ failure assessment (SOFA) score-were compared according to outcome at time-points corresponding to 0%, 25%, 50%, 75%, and 100% of the entire ECMO duration and daily during the first 7 days. A logistic regression analysis was performed to identify changes between ECMO start and end that independently predicted hospital mortality. Tidal volume, intrapulmonary shunt, arterial lactate, and SOFA score differentiated survivors and nonsurvivors early during the first 7 days and over the entire ECMO duration. Respiratory system compliance, PaO2/FiO2 ratio, arterial pH, and mean pulmonary arterial pressure showed distinct temporal course according to outcome over the entire ECMO duration. Lack of improvement of SOFA score independently predicted hospital mortality. In ARDS patients on ECMO, temporal trends of specific physiologic parameters differentiate survivors from non-survivors and could be used to monitor the evolution of lung injury. Progressive worsening of extrapulmonary organ dysfunction is associated with worse outcome.

Tracheostomy in Patients on Venovenous Extracorporeal Membrane Oxygenation: Is It Safe?

BACKGROUND

The anticoagulation and coagulopathy associated with venovenous extracorporeal membrane oxygenation (VV-ECMO) lead to concern for increased risks of tracheostomy. The purpose of this study is to evaluate the safety of tracheostomy in patients on VV-ECMO.

METHODS

Patients admitted between November 2015 and January 2019 to a dedicated intensive care unit for VV-ECMO were reviewed retrospectively.

RESULTS

96 patients underwent tracheostomy. Tracheostomy was performed percutaneously in 51 patients, open in 24, and hybrid in 21. 28 patients had postprocedure bleeding which was from the tracheostomy site in 13, the airway in 13, and both in 2. 6 patients had major tracheostomy site bleeding and 3 patients had major airway bleeding. 7 patients had minor tracheostomy site bleeding, 10 patients had minor airway bleeding, and 2 patients had minor bleeding at both. Bleeding complications were more common following percutaneous tracheostomy. Being on anticoagulation prior to tracheostomy was protective.

DISCUSSION

Bleeding following tracheostomy in VV-ECMO is common with higher bleeding rates observed for those done percutaneously. Most complications were minor. Tracheostomy in patients on VV-ECMO appears safe.

A review on extracorporeal membrane oxygenation and kidney injury

Extracorporeal membrane oxygenation (ECMO) is inevitable external life support in case of cardiac and respiratory failure since the 1970s. Acute kidney injury (AKI) and the requirement of renal replacement therapy (RRT) is a potential risk among these patients. This review aims to give an overview of the risk of AKI, RRT, and associated mortality among the patients who received ECMO for any of its indications. PubMed database was searched to find the relevant literature and the reference list of included studies was also searched for additional studies. The incidence of AKI ranged from 30% to 78% and RRT from 47% to 60% in ECMO patients. The pathophysiology of AKI in ECMO is multifactorial, and includes ischaemia, RBCs breakdown, comorbidity, conversion of zymogen form of pro-inflammatory mediators, structural alteration of the kidney, coadministration of nephrotoxic drugs, coagulation abnormality, and oxidative stress. ECMO was associated with the higher incidence of renal abnormalities, AKI, requirement of RRT, and associated mortality. Patients who underwent RRT had improved renal function and reduced overall mortality compared to the non-RRT group among the ECMO patients. Currently, there is no consensus evidence to support the superior use of the inline hemofilter system over continuous renal replacement therapy among patients who had AKI during ECMO.

The use of extracorporeal membrane oxygenation in human immunodeficiency virus-positive patients: a review of a multicenter database

AIM

We chose to evaluate the survival of extracorporeal membrane oxygenation among patients with human immunodeficiency virus in a multicenter registry.

METHODS

Retrospective case review of the Extracorporeal Life Support Organization Registry respiratory failure of all patients with human immunodeficiency virus supported with extracorporeal membrane oxygenation.

RESULTS

A total of 126 patients were included. Survival to discharge was 36%. Eight infants were supported with extracorporeal membrane oxygenation and three (37.5%) survived to discharge. Respiratory extracorporeal membrane oxygenation was the primary indication (78%) with a 39% survival, while cardiac and extracorporeal cardiopulmonary resuscitation indications accounted for 16% and 6% of patients with survivals of 30% and 12.5%, respectively. These differences did not reach significance. There were no significant differences between survivors and non-survivors in demographic data, but non-survivors had significantly more non-human immunodeficiency virus pre-extracorporeal membrane oxygenation infections than survivors. There were no differences in other pre-extracorporeal membrane oxygenation supportive therapies, mechanical ventilator settings, or arterial blood gas results between survivors and non-survivors. The median duration of mechanical ventilation prior to cannulation was 52 (interquartile range: 13-140) hours, while the median duration of the extracorporeal membrane oxygenation exposure was 237 (interquartile range: 125-622) hours. Ventilator settings were significantly lower after 24 hours compared to pre-extracorporeal membrane oxygenation settings. Complications during extracorporeal membrane oxygenation exposure including receipt of renal replacement therapy, inotropic infusions, and cardiopulmonary resuscitation were more common among non-survivors compared to survivors. Central nervous system complications were rare.

CONCLUSION

Survival among patients with human immunodeficiency virus infection who receive extracorporeal membrane oxygenation was less than 40%. Infections before extracorporeal membrane oxygenation cannulation occurred more often in non-survivors. The receipt of renal replacement therapy, inotropic infusions, or cardiopulmonary resuscitation during extracorporeal membrane oxygenation was associated with worse outcome.

Extracorporeal Membrane Oxygenation in the Emergency Department

Extracorporeal membrane oxygenation (ECMO) is a mechanical way to provide oxygenation, ventilation, and perfusion to patients with severe cardiopulmonary failure. Extracorporeal cardiopulmonary resuscitation (ECPR) describes the use of ECMO during cardiac arrest. ECPR requires an organized approach to resuscitation, cannula insertion, and pump initiation. Selecting the right patients for ECPR is an important aspect of successful programs. A solid understanding of the components of the ECMO circuit is critical to troubleshooting problems. Current evidence suggests a substantial benefit of ECPR compared with traditional CPR for refractory cardiac arrest but is limited by lack of randomized trials to date.

A Systematic Review of Preexisting Sepsis and Extracorporeal Membrane Oxygenation

We retrospectively reviewed all pertinent extracorporeal membrane oxygenation (ECMO) studies (January 1995 to September 2017) of adults with sepsis as a primary indication for intervention and its association with morbidity and mortality. Collected data included study type, ECMO configuration, outcomes, effect size, and other features. Advanced age was a risk factor for death. Compared with nonsurvivors, survivors had a lower median Sepsis-Related Organ Failure Assessment score on day 3 (15 vs. 18, p = 0.01). Biomarkers in survivors and nonsurvivors, respectively, were peak lactate (from two studies: 4.5 vs. 15.1 mmol/L, p = 0.03; 3.6 ± 3.7 vs. 3.3 ± 2.4 mmol/L, p = 0.850) and procalcitonin levels (41 vs. 164 ng/ml, p = 0.008). Bacteremia was associated with catheter colonization, and 90.5% of a group without bloodstream infections survived to discharge; ECMO weaning was possible for less than half the bloodstream infection group. Myocarditis portended favorable outcomes for patients with sepsis who received ECMO. Extracorporeal membrane oxygenation was used in immunosuppressed patients with refractory cardiopulmonary insufficiency from severe sepsis with successful weaning from ECMO for most patients. Overall survival varied substantially among studies (15.38-71.43%). Existing studies do not present well-defined patterns supporting use of ECMO in sepsis because of sample sizes and disparate study designs.

Extracorporeal membrane oxygenation for near fatal asthma with sudden cardiac arrest

INTRODUCTION

Near fatal asthma is a life-threatening disorder that requires mechanical ventilation. Near fatal asthma and COPD with sudden cardiac arrest can worsen the outcomes. Previous studies demonstrated that ECMO is a live-saving measure for near fatal asthma that does not respond to traditional treatment.

CASE STUDY

A patient with near fatal asthma (NFA) and COPD presented with high airway resistance, life-threatening acidemia and severe hypoxemia that failed to respond to conventional therapy. His hospital course was complicated by sudden cardiac arrest when preparing to initiate V-V mode extracorporeal membrane oxygenation (ECMO). The mode immediately changed from V-V to V-A, then to V-AV and finally to V-V mode in order to improve cardiac function and promote recovery of lung function.

RESULTS

On the sixth day, ECMO was removed and on the ninth day, he was extubated and transferred to the ward. Finally, the patient was discharged home on the nineteenth day after admission to be followed up in the pulmonary clinic.

CONCLUSIONS

The early application of ECMO and mode changing plausibly resulted in dramatic improvement in gas exchange and restoration of cardiac function. This case illustrates the critical role of ECMO mode changing as salvage therapy in NFA and COPD with sudden cardiac arrest.

Preemptive veno-venous ECMO support in a patient with anticipated difficult airway: A case report

This report presents a case of endotracheal metastasis in which elective veno-venous extracorporeal membrane oxygenation (VV ECMO) was used to undergo tracheal laser-surgery prior to establishment of a definitive airway. Specifically, we describe the respiratory and airway management in an adult patient from the preclinical phase throughout elective preoperative ECMO implantation to postoperative ECMO weaning and decannulation in the Intensive Care Unit. This case report lends further supports to the idea that the extracorporeal membrane oxygenation could be electively used to provide safe environment for surgery in situations where the standard maneuvers of sustaining adequate gas exchange are anticipated to fail.

Procedural volume and outcomes in patients undergoing VA-ECMO support

Background

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used in patients with critical cardiopulmonary failure. To investigate the association between hospital VA-ECMO procedure volume and outcomes in a large, nationwide registry.

Methods

By using administrative data from the German Federal Health Monitoring System, we analyzed all VA-ECMO procedures performed in Germany from 2013 to 2016 regarding the association of procedural volumes with outcomes and complications.

Results

During the study period, 10,207 VA-ECMO procedures were performed; mean age was 61 years, 43.4% had prior CPR, and 71.2% were male patients. Acute coronary syndrome was the primary diagnosis for VA-ECMO implantation (n = 6202, 60.8%). The majority of implantations (n = 5421) were performed at hospitals in the lowest volume category (≤ 50 implantations per year).

There was a significant association between annualized volume of VA-ECMO procedures and 30-day in-hospital mortality for centers with lower vs. higher volume per year. Multivariable logistic regression showed an increased 30-day in-hospital mortality at hospitals with the lowest volume category (adjusted odds ratio 1.13, 95% confidence interval [CI] 1.01–1.27, p = 0.034).

Similarly, higher likelihood for complications was observed at hospitals with lower vs. higher annual VA-ECMO volume (adjusted odds ratio 1.46, 95% CI 1.29–1.66, p = 0.001).

Conclusions

In this analysis of more than 10,000 VA-ECMO procedures for cardiogenic shock, the majority of implantations were performed at hospitals with the lowest annual volume. Thirty-day in-hospital mortality and likelihood for complications were higher at hospitals with the lowest annual VA-ECMO volume.

Highlights from the Extracorporeal Life Support Organization Registry: 2006-2017

Extracorporeal membrane oxygenation (ECMO) is a supportive therapy for patients with severe cardiovascular or respiratory failure refractory to conventional medical therapy. Improvements in ECMO technology, easy access to ECMO devices, and a greater understanding of care of ECMO patients have led to increased utilization of ECMO. The Extracorporeal Life Support Organization (ELSO) registry was established in 1984, to collect data on patients receiving ECMO support to help improve outcomes of these patients. The registry has grown to include over 400 contributing centers from 60 countries with data for more than 90,000 patients. Many investigators have used the ELSO registry to answer clinical questions on outcomes and care of this vulnerable patient population. This report provides a brief summary of 16 peer-reviewed articles that have advanced the knowledge and treatment of neonates, children, and adults supported with ECMO using data from the ELSO registry.

Factors associated with intraoperative extracorporeal membrane oxygenation support during lung transplantation

BACKGROUND

Intraoperative Extracorporeal membrane oxygenation (ECMO) is increasingly being applied as life-support for lung transplantation patients. However, factors associated with this procedure in lung transplantation patients have not yet been characterized. The aim of this study was to identify preoperative factors of intraoperative ECMO support during lung transplantation and to evaluated the outcome of lung transplantation patients supported with ECMO.

METHODS

Patients underwent lung transplantation treated with and without ECMO in Guangzhou Institute of Respiratory Diseases between January 2015 to August 2018 were retrospectively reviewed. Patient demographics and clinical variables were collected and analyzed. Multivariate logistic regression was performed to identify factors independently associated with intraoperative extracorporeal membrane oxygenation support during lung transplantation.

RESULTS

During the study period, 138 patients underwent lung transplantation at our institution, the mean LAS was (56.63 ± 18.39) (range, 32.79 to 88.70). Fourty four patients were treated with veno-venous/veno-arterial ECMO. Among the patients, 32 patients wean successfully ECMO after operation, 12 patients remain ECMO after operation, and 32 patients (62.74%) survived to hospital discharge. In multiple analysis, the following factors were associated with intraoperative ECMO support: advanced age, high PAP before operation, duration of mechanical ventilation before operation, a higher APACHE II and primary diagnosis for transplantation. The overall survival rates at 1, 3, and 12 months were 90.91, 72.73, and 56.81% in the ECMO group, and 95.40, 82.76, and 73.56% in the non-ECMO group, respectively (log-rank P = 0.081). Patients who underwent single lung transplant had a lower survival rates in ECMO group as compared with non-ECMO group at 1, 3, and 12 months (90.47% vs 98.25, 71.43% vs 84.21, and 52.38% vs 75.44%) (log-rank P = 0.048).

CONCLUSIONS

The preoperative factors of intraoperative ECMO support during lung transplantation included age, high PAP before operation, preoperative mechanical ventilation, a higher APACHE II and primary diagnosis for transplantation based on multivariate analysis.

Acute kidney disease stage predicts outcome of patients on extracorporeal membrane oxygenation support

BACKGROUND

The mortality rate of patients on extracorporeal membrane oxygenation (ECMO), especially those patients that develop acute kidney injury (AKI) is high. Acute kidney disease (AKD) is a term used to describe the continuum from AKI to chronic kidney disease. However, the role of AKD in predicting the prognosis of patients on ECMO support is unclear.

METHODS

A total of 168 patients who received ECMO support and survived for more than 7 days at a single hospital from 2003 to 2008 were enrolled for this study and followed up for 10 years or till mortality. Kaplan-Meier analysis and Cox proportional hazards model were used to determine the prognostic factors associated with survival.

RESULTS

The median survival times of patients with stage 0, stage 1, stage 2 and stage 3 AKD were ≥ 10 years, 43.9 months, 1 month, and half a month, respectively. There were statistically significant differences in cumulative survival rate between patients with stage 3 AKD and those with stage 0, 1, and 2 AKD (Cox-Mantel log rank test, p<0.001, p<0.001, p = 0.023), and between patients with stage 0 AKD and those with stage 1 and 2 AKD (Cox-Mantel log rank test, p = 0.012, p<0.001). Cox regression analysis revealed that AKD stage (hazard ratio [HR]: 2.576, 95% confidential interval [CI]: 1.268-5.234, p = 0.009 for stage 1; HR: 2.349; 95% CI: 1.101-5.512, p = 0.029 for stage 2; HR: 5.252; 95% CI: 2.715-10.163, p<0.001 for stage 3) was significant independent predictor of survival.

CONCLUSION

AKD stage is an independent predictor of survival in patients on ECMO support.

Infection profile in neonatal patients during extracorporeal membrane oxygenation

OBJECTIVES

To describe risk factors for acquired infection during neonatal extracorporeal membrane oxygenation and to examine the predictive value of inflammatory markers in the diagnosis of infection.

METHODS

A retrospective study was conducted with data for patients under 30 days supported with extracorporeal membrane oxygenation from 2003 to April 2016, in a neonatal intensive care unit.

RESULTS

Our study included 160 neonatal patients, the average age of connection was 8.5 days and the duration of extracorporeal membrane oxygenation support was 9.7 days. The incidence of confirmed infection was 23%. Patients with confirmed infection present more frequently: vaginal delivery, lower birth weight, female sex, diagnosis of congenital diaphragmatic hernia, and longer duration of extracorporeal membrane oxygenation. When comparing the group of patients with confirmed infection and suspicion of infection, there were no significant differences in the inflammatory markers. When calculating the slope for each one, the difference in white blood cell count slope 72 h before the infection is significant; in patients with confirmed infection, the count of white blood cell increases (slope: 0.25), versus the group of patients with suspected infection in whom the count decreases (slope: -0.39). No differences were found in other variables.

CONCLUSION

Our study describes that the factors that increase the risk of infection are lower birth weight, vaginal birth, duration of extracorporeal membrane oxygenation, and a positive trend of white blood cell 72 h prior to infection/suspicion. Further studies are necessary to include or definitively rule out the use of these factors and the biomarkers as predictors of infection in neonatal patients supported with extracorporeal membrane oxygenation.

Extracorporeal Membrane Oxygenation in Pregnant and Postpartum Women: A Systematic Review and Meta-Regression Analysis

Background:

Although extracorporeal membrane oxygenation (ECMO) is frequently utilized as a salvage therapy for patients with cardiopulmonary failure, outcomes of its use in peripartum patients have not been clearly established. We aimed to review peer-reviewed publications on the use of ECMO in pregnant and postpartum patients, with analyses of maternal and fetal outcomes.

Methods:

Data were retrieved from MEDLINE, EMBASE, and Scopus databases from 1972 up to November 2017 for publications on ECMO in peripartum patients. Search terms included “ECMO,” “ECLS,”, “pregnancy,” “postpartum,” and “peripartum.” Publications with 3 or more patients were reviewed for quality using the Joanna Briggs Institute checklist for prevalence studies and case series.

Results:

After reviewing 143 publications, 9 observational studies met our inclusion criteria. Pooled prevalence of maternal survival was 77.2% (95% confidence interval [CI]: 64.1%-88.4%). Pooled prevalence of fetal survival was 69.1% (95% CI: 44.7%-89.8%). The level of heterogeneity across studies was low for both outcomes. Meta-regression did not reveal any correlation between pregnant women with pulmonary or cardiac indications and maternal survival. Individual patient data meta-regression demonstrated higher odds of survival for patients on venovenous ECMO compared to those on venoarterial ECMO that was close to statistical significance (odds ratio = 3.016, 95% CI: 0.901-11.144; P = .081) after adjusting for pregnancy status.

Conclusions:

Extracorporeal membrane oxygenation can be considered as an acceptable salvage therapy for pregnant and postpartum patients with critical cardiac or pulmonary illness.