Assessment of Right Ventricular Function With CT and Echocardiography in Patients With Severe Acute Respiratory Distress Syndrome on Extracorporeal Membrane Oxygenation

Right Ventricular Injury Definition and Management in Veno-Venous Extracorporeal Membrane Oxygenation

Right ventricular injury (RVI) in respiratory failure receiving veno-venous extracorporeal membrane oxygenation (VV ECMO) is associated with significant mortality. A scoping review is necessary to map the current literature and guide future research regarding the definition and management of RVI in patients receiving VV ECMO. We searched for relevant publications on RVI in patients receiving VV ECMO in Medline, EMBASE, and Web of Science. Of 1,868 citations screened, 30 studies reported on RVI (inclusive of right ventricular dilation, right ventricular dysfunction, and right ventricular failure) during VV ECMO. Twenty-three studies reported on the definition of RVI including echocardiographic indices of RV function and dimensions, whereas 13 studies reported on the management of RVI, including veno-pulmonary (VP) ECMO, veno-arterial (VA) ECMO, positive inotropic agents, pulmonary vasodilators, ultra-lung-protective ventilation (Ultra-LPV), and optimization of positive end-expiratory pressure (PEEP). The definitions of RVI in patients receiving VV ECMO used in the literature are heterogeneous. Despite the high incidence of RVI during VV ECMO support and its strong association with mortality, studies investigating therapeutic strategies for RVI are also lacking. To fill the existing knowledge gaps, a consensus on the definition of RVI and research investigating RV-targeted therapies during VV ECMO is urgently warranted.

Right Ventricular Dysfunction in Acute Respiratory Distress Syndrome and Its Quantification by Tricuspid Annular Plane Systolic Excursion on Transthoracic Echocardiography

Background Right ventricular (RV) dysfunction is a typical complication of acute respiratory distress syndrome (ARDS), which is an independent predictor of poor prognosis in ARDS. Thus, evaluation of RV function is a crucial component of ARDS patient management. The present study aimed to determine the incidence of RV dysfunction by 2D echocardiography in mechanically ventilated ARDS patients in the ICU and assess the serial changes in tricuspid annular plane systolic excursion (TAPSE) among these patients in the intensive care unit (ICU) of a tertiary care cancer institute of Eastern India. Methods The prospective observational study included 40 patients aged 18-80 years who were admitted to the critical care unit with ARDS and put on mechanical ventilation. Patients meeting eligibility criteria underwent routine investigations on admission to the ICU. Key parameters included recording of the partial pressure of oxygen/fraction of inspired oxygen (PaO2/FiO2) oxygenation index, TAPSE on 2D transthoracic echocardiography, and plasma B-type (or brain) natriuretic peptide (BNP) level estimation conducted on day 0, day 2, and day 5. A TAPSE value <17 mm was considered to indicate RV dysfunction. Weaning outcomes, ventilator days, length of ICU stay, length of hospital stay, and in-ICU mortality were noted. Results Among the 40 study participants, the mean (± SD) age was 52.6 (± 14.3) years, and 52.5% were male patients. The incidence of RV dysfunction in ARDS was 17.5%. These patients were observed to have a progressive worsening of hypoxia along with a significant elevation of plasma BNP levels on day 2 and day 5 as compared to baseline. Weaning outcomes, ventilator days, length of hospital stay, and in-ICU mortality were comparable between the two groups. Conclusion The present study reports a 17.5% incidence of RV dysfunction in ARDS and quantifies a longitudinal deterioration in RV function with the onset of ARDS using TAPSE. The inclusion of objective indices on two-dimensional echocardiography, such as TAPSE, facilitates their regular application at the bedside and equips clinicians with a means to detect and quantify RV dysfunction in its early stages in ARDS.

Definition and management of right ventricular injury in adult patients receiving extracorporeal membrane oxygenation for respiratory support using the Delphi method: a PRORVnet study. Expert position statements

PURPOSE

Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is an integral part of the management algorithm of patients with severe respiratory failure refractory to evidence-based conventional treatments. Right ventricular injury (RVI) pertaining to abnormalities in the dimensions and/or function of the right ventricle (RV) in the context of VV-ECMO significantly influences mortality. However, in the absence of a universally accepted RVI definition and evidence-based guidance for the management of RVI in this very high-risk patient cohort, variations in clinical practice continue to exist.

METHODS

Following a systematic search of the literature, an international Steering Committee consisting of eight healthcare professionals involved in the management of patients receiving ECMO identified domains and knowledge gaps pertaining to RVI definition and management where the evidence is limited or ambiguous. Using a Delphi process, an international panel of 52 Experts developed Expert position statements in those areas. The process also conferred RV-centric overarching open questions for future research. Consensus was defined as achieved when 70% or more of the Experts agreed or disagreed on a Likert-scale statement or when 80% or more of the Experts agreed on a particular option in multiple-choice questions.

RESULTS

The Delphi process was conducted through four rounds and consensus was achieved on 31 (89%) of 35 statements from which 24 Expert position statements were derived. Expert position statements provided recommendations for RVI nomenclature in the setting of VV-ECMO, a multi-modal diagnostic approach to RVI, the timing and parameters of diagnostic echocardiography, and VV-ECMO settings during RVI assessment and management. Consensus was not reached on RV-protective driving pressure thresholds or the effect of prone positioning on patient-centric outcomes.

CONCLUSION

The proposed definition of RVI in the context of VV-ECMO needs to be validated through a systematic aggregation of data across studies. Until further evidence emerges, the Expert position statements can guide informed decision-making in the management of these patients.

Right Ventricular Injury Increases Mortality in Patients With Acute Respiratory Distress Syndrome on Veno-Venous Extracorporeal Membrane Oxygenation: A Systematic Review and Meta-Analysis

Right ventricular injury (RVI) in the context of acute respiratory distress syndrome (ARDS) is well recognized as an important determinant risk factor of mortality. Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is part of the algorithm for the management of patients with severe ARDS and severely impaired gas exchange. Although VV-ECMO may theoretically protect the RV it is uncertain to what degree RVI persists despite VV-ECMO support, and whether it continues to influence mortality after ECMO initiation. The aim of this systematic review and meta-analysis was to investigate the impact of RVI on mortality in this context, testing the hypothesis that RVI worsens mortality in this cohort. We performed a systematic search that identified seven studies commenting on RVI and mortality in patients with ARDS receiving VV-ECMO. The presence of RVI was associated with greater mortality overall (odds ratios [OR]: 2.72; 95% confidence intervals [CI]: 1.52-4.85; p < 0.00) and across three subgroups (RV dilatational measures: OR: 3.51; 95% CI: 1.51-8.14; p < 0.01, RV functional measures: OR: 1.84; 95% CI: 0.99-3.42; p = 0.05, RV measurements post-ECMO initiation: OR: 1.94; 95% CI: 1.01-3.72; p < 0.05). Prospective studies are needed to investigate the causal relationship between RVI and mortality in this patient group and the best management strategies to reduce mortality.

Percutaneous Pulmonary Artery Cannulation to Treat Acute Secondary Right Heart Failure While on Veno-venous Extracorporeal Membrane Oxygenation

Right heart failure (RHF) is a common, yet difficult to manage, complication of severe acute respiratory distress syndrome requiring extracorporeal membrane oxygenation (ECMO) that is associated with increased mortality. Reports of the use of percutaneous mechanical circulatory support devices for concurrent right heart and respiratory failure are limited. This series describes the percutaneous cannulation of the pulmonary artery for conversion from veno-venous to veno-pulmonary artery return ECMO in 21 patients who developed secondary RHF. All patients cannulated between May 2019 and September 2021 were included. Either a 19 or 21 French venous cannula was placed percutaneously into the pulmonary artery via the internal jugular or subclavian vein, providing a total of 821 days of support (median 23 [4-71] days per patient) with flows up to 6 L/min. Five patients underwent cannulation at the bedside, with the remainder performed in the cardiac catheterization laboratory. Pulmonary artery cannulation occurred after 12 [8.5-23.5] days of ECMO support. Vasoactive infusion requirements decreased significantly within 24 hours of pulmonary artery cannula placement (p = 0.0004). Nonetheless, 75% of these patients expired after a median of 12 [4-63] days of support, with three patients found to have had significant pericardial effusions peri-arrest. This cannulation technique may be an effective alternative to veno-arterial ECMO cannulation or the placement of a dual-lumen cannula for the treatment of RHF.

[Extracorporeal membrane oxygenation and hemodynamics : Therapy is not only a friend of the heart]

Extracorporeal support systems for the heart and lungs are employed for cardiac, pulmonary and also cardiopulmonary failure; however, neither the pure lung support by venovenous extracorporeal membrane oxygenation (vvECMO) nor the venoarterial (va) ECMO behave in a hemodynamically inert manner with respect to the patient's own cardiovascular system. The success of ECMO treatment is decisively dependent on monitoring before and during the execution and the pathophysiological understanding of the hemodynamic changes that occur during treatment. This article explicitly elucidates these "concomitant phenomena" and discusses fundamental aspects of cardiovascular physiology and the specific interplay with ECMO treatment.

Fundamentals of vaping-associated pulmonary injury leading to severe respiratory distress

Vaping of flavored liquids has been touted as safe alternative to traditional cigarette smoking with decreased health risks. The popularity of vaping has dramatically increased over the last decade, particularly among teenagers who incorporate vaping into their daily life as a social activity. Despite widespread and increasing adoption of vaping among young adults, there is little information on long-term consequences of vaping and potential health risks. This study demonstrates vaping-induced pulmonary injury using commercial JUUL pens with flavored vape juice using an inhalation exposure murine model. Profound pathological changes to upper airway, lung tissue architecture, and cellular structure are evident within 9 wk of exposure. Marked histologic changes include increased parenchyma tissue density, cellular infiltrates proximal to airway passages, alveolar rarefaction, increased collagen deposition, and bronchial thickening with elastin fiber disruption. Transcriptional reprogramming includes significant changes to gene families coding for xenobiotic response, glycerolipid metabolic processes, and oxidative stress. Cardiac systemic output is moderately but significantly impaired with pulmonary side ventricular chamber enlargement. This vaping-induced pulmonary injury model demonstrates mechanistic underpinnings of vaping-related pathologic injury.

VAPIng into ARDS: Acute Respiratory Distress Syndrome and Cardiopulmonary Failure

"Modern" vaping involving battery-operated electronic devices began approximately one dozen years and has quickly evolved into a multibillion dollar industry providing products to an estimated 50 million users worldwide. Originally developed as an alternative to traditional cigarette smoking, vaping now appeals to a diverse demographic including substantial involvement of young people who often have never used cigarettes. The rapid rise of vaping fueled by multiple factors has understandably outpaced understanding of biological effects, made even more challenging due to wide ranging individual user habits and preferences. Consequently while vaping-related research gathers momentum, vaping-associated pathological injury (VAPI) has been established by clinical case reports with severe cases manifesting as acute respiratory distress syndrome (ARDS) with examples of right ventricular cardiac failure. Therefore, basic scientific studies are desperately needed to understand the impact of vaping upon the lungs as well as cardiopulmonary structure and function. Experimental models that capture fundamental characteristics of vaping-induced ARDS are essential to study pathogenesis and formulate recommendations to mitigate harmful effects attributable to ingredients or equipment. So too, treatment strategies to promote recovery from vaping-associated damage require development and testing at the preclinical level. This review summarizes the back story of vaping leading to present day conundrums with particular emphasis upon VAPI-associated ARDS and prioritization of research goals.

Persistent Right Ventricle Dilatation in SARS-CoV-2-Related Acute Respiratory Distress Syndrome on Extracorporeal Membrane Oxygenation Support

Objectives

Venovenous extracorporeal membrane oxygenation (ECMO) support may be considered in experienced centers for patients with acute respiratory distress syndrome (ARDS) due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection refractory to conventional treatment. In ECMO patients, echocardiography has emerged as a clinical tool for implantation and clinical management; but to date, little data are available on COVID-related ARDS patients requiring ECMO. The authors assessed the incidence of right ventricular dilatation and dysfunction (RvDys) in patients with COVID-related ARDS requiring ECMO.

Design

Single-center investigation.

Setting

Intensive care unit (ICU).

Participants

A total of 35 patients with COVID-related ARDS requiring ECMO, consecutively admitted to the ICU (March 1, 2020, to February 28, 2021).

Interventions

Serial echocardiographic examinations. RvDys was defined as RV end-diastolic area/LV end-diastolic area >0.6 and tricuspid annular plane excursion <15 mm.

Measurements and Main Results

The incidence of RvDys was 15/35 (42%). RvDys patients underwent ECMO support after a longer period of mechanical ventilation (p = 0.006) and exhibited a higher mortality rate (p = 0.024) than those without RvDys. In nonsurvivors, RvDys was observed in all patients (n = nine) who died with unfavorable progression of COVID-related ARDS. In survivors, weaned from ECMO, a significant reduction in systolic pulmonary arterial pressures was detectable.

Conclusions

According to the authors’ data, in COVID-related ARDS requiring ECMO support, RvDys is common, associated with increased ICU mortality. Overall, the data underscored the clinical role of echocardiography in COVID-related ARDS supported by venovenous ECMO, because serial echocardiographic assessments (especially focused on RV changes) are able to reflect pulmonary COVID disease severity.

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.