Extracorporeal membrane oxygenation for adult respiratory distress syndrome in trauma patients: A case series and systematic literature review

Novel Non-surgical Strategy of Severe Chest Trauma With Venovenous Extracorporeal Membrane Oxygenation, Angioembolization, and Bronchial Blocker: A Case Report

Severe chest trauma often requires immediate intervention, typically involving open chest surgery. However, advancements in medical technology offer alternative approaches, such as endovascular therapy and venovenous extracorporeal membrane oxygenation (VV-ECMO). In a recent case, a middle-aged male cyclist was admitted after colliding with a vehicle, presenting in shock with multiple injuries, including cerebral contusion and rib fractures. Despite initial treatments such as chest tubes and blood transfusions, his condition remained unstable, with worsening respiratory failure and hemorrhagic shock. A multidisciplinary team devised a comprehensive treatment plan, utilizing VV-ECMO for oxygenation support, a bronchial blocker to localize the hematoma, and interventional radiology for hemothorax hemostasis. These interventions successfully stabilized the patient without resorting to open chest surgery. Endovascular therapy, alongside bronchial blockers, facilitated adequate hemostasis and hematoma localization, avoiding invasive procedures. VV-ECMO plays a crucial role in maintaining oxygenation during respiratory failure. Strategic anticoagulation with nafamostat mesylate prevented clotting in the ECMO circuit. This case highlights the effectiveness of minimally invasive strategies in managing severe chest trauma, preserving lung function, and improving outcomes. In refractory cases, VV-ECMO acts as a bridge to stabilize respiratory status before definitive treatment, while bronchial blockers localize hematomas, reducing the need for surgery. Interventional radiology offers a less invasive option for achieving hemostasis. Collaboration among medical specialties and innovative technologies is critical to successfully navigating complex chest trauma cases.

ECMO in trauma care: What you need to know

ABSTRACT

Over the past 10 years, extracorporeal membrane oxygenation (ECMO) use in trauma patients has increased significantly. This includes adult and pediatric trauma patients and even combat casualties. Most ECMO applications are in a venovenous (VV ECMO) configuration for acute hypoxemic respiratory failure or anatomic injuries that require pneumonectomy or extreme lung rest in a patient with insufficient respiratory reserve. In this narrative review, we summarize the most common indications for VV ECMO and other forms of ECMO support used in critically injured patients, underscore the importance of early ECMO consultation or regional referral, review the technical aspects of ECMO cannulation and management, and examine the expected outcomes for these patients. In addition, we evaluate the data where it exists to try to debunk some common myths surrounding ECMO management.

Venovenous extracorporeal membrane oxygenation in patients with traumatic brain injuries and severe respiratory failure: A single-center retrospective analysis

BACKGROUND

Venovenous extracorporeal membrane oxygenation (VV ECMO) can support trauma patients with severe respiratory failure. Use in traumatic brain injury (TBI) may raise concerns of worsening complications from intracranial bleeding. However, VV ECMO can rapidly correct hypoxemia and hypercarbia, possibly preventing secondary brain injury. We hypothesize that adult trauma patients with TBI on VV ECMO have comparable survival with trauma patients without TBI.

METHODS

A single-center, retrospective cohort study involving review of electronic medical records of trauma admissions between July 1, 2014, and August 30, 2022, with discharge diagnosis of TBI who were placed on VV ECMO during their hospital course was performed.

RESULTS

Seventy-five trauma patients were treated with VV ECMO; 36 (48%) had TBI. Of those with TBI, 19 (53%) had a hemorrhagic component. Survival was similar between patients with and without a TBI (72% vs. 64%, p = 0.45). Traumatic brain injury survivors had a higher admission Glasgow Coma Scale (7 vs. 3, p < 0.001) than nonsurvivors. Evaluation of prognostic scoring systems on initial head computed tomography demonstrated that TBI VV ECMO survivors were more likely to have a Rotterdam score of 2 (62% vs. 20%, p = 0.03) and no survivors had a Marshall score of ≥4. Twenty-nine patients (81%) had a repeat head computed tomography on VV ECMO with one incidence of expanding hematoma and one new focus of bleeding. Neither patient with a new/worsening bleed received anticoagulation. Survivors demonstrated favorable neurologic outcomes at discharge and outpatient follow-up, based on their mean Rancho Los Amigos Scale (6.5; SD, 1.2), median Cerebral Performance Category (2; interquartile range, 1-2), and median Glasgow Outcome Scale-Extended (7.5; interquartile range, 7-8).

CONCLUSION

In this series, the majority of TBI patients survived and had good neurologic outcomes despite a low admission Glasgow Coma Scale. Venovenous extracorporeal membrane oxygenation may minimize secondary brain injury and may be considered in select patients with TBI.

LEVEL OF EVIDENCE

Prognostic and Epidemiological; Level IV.

Predictors of Mortality in Extracorporeal Membrane Oxygenation Support Patients Following Major Trauma

INTRODUCTION

The usage of extracorporeal membrane oxygenation (ECMO) in trauma patients has increased significantly within the past decade. Despite increased research on ECMO application in trauma patients, there remains limited data on factors predicting morbidity and mortality outcome. Therefore, the primary objective of this study is to describe patient characteristics that are independently associated with mortality in ECMO therapy in trauma patients, to further guide future research.

METHODS

This retrospective study was conducted using the Trauma Quality Improvement Program database from 2010 to 2019. All adult (age ≥ 16 y) trauma patients that utilized ECMO were included. A Significant differences (P < 0.05) in demographic and clinical characteristics between groups were calculated using an independent t-test for normal distributed continuous values, a Mann-Whitney U test for non-normal distributed values, and a Pearson chi-square test for categorical values. A multivariable regression model was used to identify independent predictors for mortality. A survival flow chart was constructed by using the strongest predictive value for mortality and using the optimal cut-off point calculated by the Youden index.

RESULTS

Five hundred forty-two patients were included of whom 205 died. Multivariable analysis demonstrated that the female gender, ECMO within 4 h after presentation, a decreased Glasgow Coma Scale, increased age, units of blood in the first 4 h, and abbreviated injury score for external injuries were independently associated with mortality in ECMO trauma patients. It was found that an external abbreviated injury score of ≥3 had the strongest predictive value for mortality, as patients with this criterion had an overall 29.5% increased risk of death.

CONCLUSIONS

There is an ongoing increasing trend in the usage of ECMO in trauma patients. This study has identified multiple factors that are individually associated with mortality. However, more research must be done on the association between mortality and noninjury characteristics like Pao2/Fio2 ratio, acute respiratory distress syndrome classification, etc. that reflect the internal state of the patient.

Review of anticoagulation considerations in extracorporeal membrane oxygenation support

Since its first success in 1975, extracorporeal membrane oxygenation (ECMO) has been used with increasing frequency for pulmonary and cardiopulmonary bypass. Use in adults has increased exponentially since the early 2000s, but despite thousands of international cannulations using both veno-arterial (VA) and veno-venous (VV) ECMO, there are still significant hemocompatibility-related adverse events. Current management of anticoagulation has been based on the Extracorporeal Life Support Organization guidance published in 2014 with recent updates published in 2022. Despite this guidance, there is still limited international consensus on how to manage anticoagulation in ECMO. For this review, we completed a comprehensive search of multiple electronic databases to identify studies pertaining to anticoagulation of adult patients on VV or VA-ECMO. The highest priority was given to sources that were prospective, randomized, controlled studies, but in the absence of such resources, observational studies, retrospective uncontrolled studies, and case series/reports were considered for inclusion. This document serves to provide a comprehensive review of the current understanding of management pertaining to anticoagulation relating to ECMO.

Pediatric surgical interventions on ECMO

Extra Corporeal Membrane Oxygenation (ECMO) has historically been reserved for refractory pulmonary and cardiac support in children and adult. Operative intervention on ECMO was traditionally contraindicated due to hemorrhagic complications exacerbated by critical illness and anticoagulation needs. With advancements in ECMO circuitry and anticoagulation strategies operative procedures during ECMO have become feasible with minimal hemorrhagic risks. Here we review anticoagulation and operative intervention considerations in the pediatric population during ECMO cannulation. Pediatric surgical interventions currently described in the literature while on ECMO support include thoracotomy/thoracoscopy, tracheostomy, laparotomy, and injury related procedures i.e. wound debridement. A patient should not be precluded from a surgical intervention while on ECMO, if the surgery is indicated.

The importance of monitoring cerebral oxygenation in non brain injured patients

Over the past few years, the use of non-invasive neuromonitoring in non-brain injured patients has increased, as a result of the recognition that many of these patients are at risk of brain injury in a wide number of clinical scenarios and therefore may benefit from its application which allows interventions to prevent injury and improve outcome. Among these, are post cardiac arrest syndrome, sepsis, liver failure, acute respiratory failure, and the perioperative settings where in the absence of a primary brain injury, certain groups of patients have high risk of neurological complications. While there are many neuromonitoring modalities utilized in brain injured patients, the majority of those are either invasive such as intracranial pressure monitoring, require special skill such as transcranial Doppler ultrasonography, or intermittent such as pupillometry and therefore unable to provide continuous monitoring. Cerebral oximetry using Near infrared Spectroscopy, is a simple non invasive continuous measure of cerebral oxygenation that has been shown to be useful in preventing cerebral hypoxemia both within the intensive care unit and the perioperative settings. At present, current recommendations for standard monitoring during anesthesia or in the general intensive care concentrate mainly on hemodynamic and respiratory monitoring without specific indications regarding the brain, and in particular, brain oximetry. The aim of this manuscript is to provide an up-to-date overview of the pathophysiology and applications of cerebral oxygenation in non brain injured patients as part of non-invasive multimodal neuromonitoring in the early identification and treatment of neurological complications in this population.

Research progress of portable extracorporeal membrane oxygenation

INTRODUCTION

Extracorporeal membrane oxygenation (ECMO) is primarily used for the supportive treatment of patients suffering from severe cardiopulmonary failure. With the continued development of ECMO technology, the relevant scenarios also extend pre-hospital and inter-hospital. In order to meet the needs of emergency treatment in communities, disaster sites and battlefields, inter-hospital transfer and evacuation; miniaturized and portable ECMO has become a current research hotspot.

AREA COVERED

The paper first introduces the principle, composition and common modes of ECMO and summarizes the research status of portable ECMO, Novalung and wearable ECMO, analyzes the characteristics and shortcomings of existing equipment. finally, we discussed the focus and development trend of portable ECMO technology.

EXPERT OPINION

Currently, portable ECMO has many applications in interhospital transport and there are various studies on portable and wearable ECMO devices, but the development of portable ECMO still faces many challenges. In the future, research related to integrated components, rich sensor arrays, Intelligent ECMO system and lightweight technology can make future portable ECMO more suitable for pre-hospital emergency and interhospital transport.

[Pathophysiology, Diagnostics and Therapy of Pulmonary Contusion - Recommendations of the Interdisciplinary Group on Thoracic Trauma of the Section NIS of the German Society for Trauma Surgery (DGU) and the German Society for Thoracic Surgery (DGT)]

Pulmonary contusion usually occurs in combination with other injuries and is indicative of a high level of force. Especially in multiply injured patients, pulmonary contusions are frequently detected. The injury is characterised by dynamic development, which might result in difficulties in recognising the actual extent of the injury at an early stage. Subsequently, correct classification of the extent of injury and appropriate initiation of therapeutic steps are essential to achieve the best possible outcome. The main goal of all therapeutic measures is to preserve lung function as best as possible and to avoid associated complications such as the development of pneumonia or Acute Respiratory Distress Syndrome (ARDS).The present report from the interdisciplinary working group "Chest Trauma" of the German Society for Trauma Surgery (DGU) and the German Society for Thoracic Surgery (DGT) includes an extensive literature review on the background, diagnosis and treatment of pulmonary contusion. Without exception, papers with a low level of evidence were included due to the lack of studies with large cohorts of patients or randomised controlled studies. Thus, the recommendations given in the present article correspond to a consensus of the aforementioned interdisciplinary working group.Computed tomography (CT) of the chest is recommended for initial diagnosis; the extent of pulmonary contusion correlates with the incidence and severity of complications. A conventional chest X-ray may initially underestimate the injury, but is useful during short-term follow-up.Therapy for pulmonary contusion is multimodal and symptom-based. In particular, intensive care therapy with lung-protective ventilation and patient positioning are key factors of treatment. In addition to invasive ventilation, non-invasive ventilation should be considered if the patient's comorbidities and compliance allows this. Furthermore, depending on the extent of the lung injury and the general patient's condition, ECMO therapy may be considered as an ultima ratio. In particular, this should only be performed at specialised hospitals, which is why patient assignment or anticipation of early transfer of the patient should be anticipated at an early time during the course.

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.

Anticoagulation Management during Extracorporeal Membrane Oxygenation-A Mini-Review

Extracorporeal membrane oxygenation (ECMO) has been established as a life-saving technique for patients with the most severe forms of respiratory or cardiac failure. It can, however, be associated with severe complications. Anticoagulation therapy is required to prevent ECMO circuit thrombosis. It is, however, associated with an increased risk of hemocoagulation disorders. Thus, safe anticoagulation is a cornerstone of ECMO therapy. The most frequently used anticoagulant is unfractionated heparin, which can, however, cause significant adverse effects. Novel drugs (e.g., argatroban and bivalirudin) may be superior to heparin in the better predictability of their effects, functioning independently of antithrombin, inhibiting thrombin bound to fibrin, and eliminating heparin-induced thrombocytopenia. It is also necessary to keep in mind that hemocoagulation tests are not specific, and their results, used for setting up the dosage, can be biased by many factors. The knowledge of the advantages and disadvantages of particular drugs, limitations of particular tests, and individualization are cornerstones of prevention against critical events, such as life-threatening bleeding or acute oxygenator failure followed by life-threatening hypoxemia and hemodynamic deterioration. This paper describes the effects of anticoagulant drugs used in ECMO and their monitoring, highlighting specific conditions and factors that might influence coagulation and anticoagulation measurements.

Use of venovenous extracorporeal membrane oxygenation in trauma patients with severe adult respiratory distress syndrome: A retrospective study

BACKGROUND

The use of extracorporeal membrane oxygenation (ECMO) has increased, although its survival benefit in trauma patients with severe adult respiratory distress syndrome (ARDS) remains controversial. We investigated the effect of veno-venous (VV)-ECMO on the clinical outcomes of trauma patients with severe ARDS.

METHODS

This was a retrospective study at a single center comprising trauma patients admitted between January 2013 and December 2017, diagnosed with severe ARDS using the Berlin definition (PaO2/FiO2 ratio ⩽100), in the 7 days following trauma. Patients were managed with VV-ECMO or conventional mechanical ventilation (CMV). The primary outcome was in-hospital mortality (mortality at 60 days); secondary outcomes comprised 28-day mortality, hospital length of stay (LOS), intensive care unit (ICU) LOS, ICU-free days, duration of mechanical ventilation (MV), and MV-free days. Propensity score matching was performed to adjust for the baseline differences.

RESULTS

Sixteen patients (22.5%) were managed with VV-ECMO and 55 were managed with CMV. After matching, the in-hospital mortality rate (43.8% vs 53.1%; p = 0.760), 28-day mortality rate (37.5% vs 31.3%; p = 0.750), median hospital LOS (39.5 vs 36.5 days; p = 0.533), ICU-free days (0 vs 0 days; p = 0.241), and MV-free days (0 vs 0 days; p = 0.272) did not significantly differ between the VV-ECMO and CMV groups.

CONCLUSION

In-hospital mortality (mortality at 60 days) did not differ significantly between the VV-ECMO and CMV groups. Although the safety of ECMO in trauma patients requires further investigation, VV-ECMO may be considered as a rescue therapy.

A Comparison of Anticoagulation Strategies in Veno-venous Extracorporeal Membrane Oxygenation

Bleeding remains a major source of morbidity associated with veno-venous extracorporeal membrane oxygenation (VV-ECMO). Moreover, there remains significant controversy, and a paucity of data regarding the ideal anticoagulation strategy for VV-ECMO patients. All patients undergoing isolated, peripheral VV-ECMO between January 2009 and December 2014 at our institution were retrospectively reviewed. Patients (n = 123) were stratified into one of three sequential eras of anticoagulation strategies: activated clotting time (ACT: 160-180 seconds, n = 53), high-partial thromboplastin time (H-PTT: 60-80 seconds, n = 25), and low-PTT (L-PTT: 45-55 seconds, n = 25) with high-flow (>4 L/min). Pre-ECMO APACHE II scores, SOFA scores, and Murray scores were not significantly different between the groups. Patients in the L-PTT group required less red blood cell units on ECMO than the ACT or H-PTT group (2.1 vs. 1.3 vs. 0.9; p < 0.001) and patients in the H-PTT and L-PTT group required less fresh frozen plasma than the ACT group (0.33 vs. 0 vs. 0; p = 0.006). Overall, major bleeding events were significantly lower in the L-PTT group than in the ACT and H-PTT groups. There was no difference in thrombotic events. In this single-institution experience, a L-PTT, high-flow strategy on VV-ECMO was associated with fewer bleeding and no difference in thrombotic events than an ACT or H-PTT strategy.

Pulmonary complications and respiratory management in neurocritical care: a narrative review

ABSTRACT

Neurocritical care (NCC) is not only generally guided by principles of general intensive care, but also directed by specific goals and methods. This review summarizes the common pulmonary diseases and pathophysiology affecting NCC patients and the progress made in strategies of respiratory support in NCC. This review highlights the possible interactions and pathways that have been revealed between neurological injuries and respiratory diseases, including the catecholamine pathway, systemic inflammatory reactions, adrenergic hypersensitivity, and dopaminergic signaling. Pulmonary complications of neurocritical patients include pneumonia, neurological pulmonary edema, and respiratory distress. Specific aspects of respiratory management include prioritizing the protection of the brain, and the goal of respiratory management is to avoid inappropriate blood gas composition levels and intracranial hypertension. Compared with the traditional mode of protective mechanical ventilation with low tidal volume (Vt), high positive end-expiratory pressure (PEEP), and recruitment maneuvers, low PEEP might yield a potential benefit in closing and protecting the lung tissue. Multimodal neuromonitoring can ensure the safety of respiratory maneuvers in clinical and scientific practice. Future studies are required to develop guidelines for respiratory management in NCC.

Ventilation management and outcomes in out-of-hospital cardiac arrest: a protocol for a preplanned secondary analysis of the TTM2 trial

INTRODUCTION

Mechanical ventilation is a fundamental component in the management of patients post cardiac arrest. However, the ventilator settings and the gas-exchange targets used after cardiac arrest may not be optimal to minimise post-anoxic secondary brain injury. Therefore, questions remain regarding the best ventilator management in such patients.

METHODS AND ANALYSIS

This is a preplanned analysis of the international randomised controlled trial, targeted hypothermia versus targeted normothermia after out-of-hospital cardiac arrest (OHCA)-target temperature management 2 (TTM2). The primary objective is to describe ventilatory settings and gas exchange in patients who required invasive mechanical ventilation and included in the TTM2 trial. Secondary objectives include evaluating the association of ventilator settings and gas-exchange values with 6 months mortality and neurological outcome. Adult patients after an OHCA who were included in the TTM2 trial and who received invasive mechanical ventilation will be eligible for this analysis. Data collected in the TTM2 trial that will be analysed include patients' prehospital characteristics, clinical examination, ventilator settings and arterial blood gases recorded at hospital and intensive care unit (ICU) admission and daily during ICU stay.

ETHICS AND DISSEMINATION

The TTM2 study has been approved by the regional ethics committee at Lund University and by all relevant ethics boards in participating countries. No further ethical committee approval is required for this secondary analysis. Data will be disseminated to the scientific community by abstracts and by original articles submitted to peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT02908308.

2021 ELSO Adult and Pediatric Anticoagulation Guidelines

DISCLAIMER

These guidelines for adult and pediatric anticoagulation for extracorporeal membrane oxygenation are intended for educational use to build the knowledge of physicians and other health professionals in assessing the conditions and managing the treatment of patients undergoing ECLS / ECMO and describe what are believed to be useful and safe practice for extracorporeal life support (ECLS, ECMO) but these are not necessarily consensus recommendations. The aim of clinical guidelines are to help clinicians to make informed decisions about their patients. However, adherence to a guideline does not guarantee a successful outcome. Ultimately, healthcare professionals must make their own treatment decisions about care on a case-by-case basis, after consultation with their patients, using their clinical judgment, knowledge and expertise. These guidelines do not take the place of physicians' and other health professionals' judgment in diagnosing and treatment of particular patients. These guidelines are not intended to and should not be interpreted as setting a standard of care or be deemed inclusive of all proper methods of care nor exclusive of other methods of care reasonably directed to obtaining the same results. The ultimate judgment must be made by the physician and other health professionals and the patient in light of all the circumstances presented by the individual patient, and the known variability and biological behavior of the clinical condition. These guidelines reflect the data at the time the guidelines were prepared; the results of subsequent studies or other information may cause revisions to the recommendations in these guidelines to be prudent to reflect new data, but ELSO is under no obligation to provide updates. In no event will ELSO be liable for any decision made or action taken in reliance upon the information provided through these guidelines.

Modalities of Exercise Training in Patients with Extracorporeal Membrane Oxygenation Support

The aim of this qualitative systematic review is to summarize and analyze the different modalities of exercise training and its potential effects in patients on extracorporeal membrane oxygenation (ECMO) support. ECMO is an outbreaking, life-saving technology of the last decades which is being used as a gold standard treatment in patients with severe cardiac, respiratory or combined cardiorespiratory failure. Critically ill patients on ECMO very often present intensive care unit-acquired weakness (ICU-AW); thus, leading to decreased exercise capacity and increased mortality rates. Early mobilization and physical therapy have been proven to be safe and feasible in critically ill patients on ECMO, either as a bridge to lung/heart transplantation or as a bridge to recovery. Rehabilitation has beneficial effects from the early stages in the ICU, resulting in the prevention of ICU-AW, and a decrease in episodes of delirium, the duration of mechanical ventilation, ICU and hospital length of stay, and mortality rates. It also improves functional ability, exercise capacity, and quality of life. Rehabilitation requires a very careful, multi-disciplinary approach from a highly specialized team from different specialties. Initial risk assessment and screening, with appropriate physical therapy planning and exercise monitoring in patients receiving ECMO therapy are crucial factors for achieving treatment goals. However, more randomized controlled trials are required in order to establish more appropriate individualized exercise training protocols.

Comparisons of Outcomes between Patients with Direct and Indirect Acute Respiratory Distress Syndrome Receiving Extracorporeal Membrane Oxygenation

Acute respiratory distress syndrome (ARDS) is a heterogeneous syndrome caused by direct (local damage to lung parenchyma) or indirect lung injury (insults from extrapulmonary sites with acute systemic inflammatory response), the clinical and biological complexity can have a profound effect on clinical outcomes. We performed a retrospective analysis of 152 severe ARDS patients receiving extracorporeal membrane oxygenation (ECMO). Our objective was to assess the differences in clinical characteristics and outcomes of direct and indirect ARDS patients receiving ECMO. Overall hospital mortality was 53.3%. A total of 118 patients were assigned to the direct ARDS group, and 34 patients were assigned to the indirect ARDS group. The 28-, 60-, and 90-day hospital mortality rates were significantly higher among indirect ARDS patients (all p < 0.05). Cox regression models demonstrated that among direct ARDS patients, diabetes mellitus, immunocompromised status, ARDS duration before ECMO, and SOFA score during the first 3 days of ECMO were independently associated with mortality. In indirect ARDS patients, SOFA score and dynamic compliance during the first 3 days of ECMO were independently associated with mortality. Our findings revealed that among patients receiving ECMO, direct and indirect subphenotypes of ARDS have distinct clinical outcomes and different predictors for mortality.

Multicentre observational study on practice of ventilation in brain injured patients: the VENTIBRAIN study protocol

INTRODUCTION

Mechanical ventilatory is a crucial element of acute brain injured patients' management. The ventilatory goals to ensure lung protection during acute respiratory failure may not be adequate in case of concomitant brain injury. Therefore, there are limited data from which physicians can draw conclusions regarding optimal ventilator management in this setting.

METHODS AND ANALYSIS

This is an international multicentre prospective observational cohort study. The aim of the 'multicentre observational study on practice of ventilation in brain injured patients'-the VENTIBRAIN study-is to describe the current practice of ventilator settings and mechanical ventilation in acute brain injured patients. Secondary objectives include the description of ventilator settings among different countries, and their association with outcomes. Inclusion criteria will be adult patients admitted to the intensive care unit (ICU) with a diagnosis of traumatic brain injury or cerebrovascular diseases (intracranial haemorrhage, subarachnoid haemorrhage, ischaemic stroke), requiring intubation and mechanical ventilation and admission to the ICU. Exclusion criteria will be the following: patients aged <18 years; pregnant patients; patients not intubated or not mechanically ventilated or receiving only non-invasive ventilation. Data related to clinical examination, neuromonitoring if available, ventilator settings and arterial blood gases will be recorded at admission and daily for the first 7 days and then at day 10 and 14. The Glasgow Outcome Scale Extended on mortality and neurological outcome will be collected at discharge from ICU, hospital and at 6 months follow-up.

ETHICS AND DISSEMINATION

The study has been approved by the Ethic committee of Brianza at the Azienda Socio Sanitaria Territoriale-Monza. Data will be disseminated to the scientific community by abstracts submitted to the European Society of Intensive Care Medicine annual conference and by original articles submitted to peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04459884.

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.

Monitoring lung injury with particle flow rate in LPS- and COVID-19-induced ARDS

In severe acute respiratory distress syndrome (ARDS), extracorporeal membrane oxygenation (ECMO) is a life-prolonging treatment, especially among COVID-19 patients. Evaluation of lung injury progression is challenging with current techniques. Diagnostic imaging or invasive diagnostics are risky given the difficulties of intra-hospital transportation, contraindication of biopsies, and the potential for the spread of infections, such as in COVID-19 patients. We have recently shown that particle flow rate (PFR) from exhaled breath could be a noninvasive, early detection method for ARDS during mechanical ventilation. We hypothesized that PFR could also measure the progress of lung injury during ECMO treatment. Lipopolysaccharide (LPS) was thus used to induce ARDS in pigs under mechanical ventilation. Eight were connected to ECMO, whereas seven animals were not. In addition, six animals received sham treatment with saline. Four human patients with ECMO and ARDS were also monitored. In the pigs, as lung injury ensued, the PFR dramatically increased and a particular spike followed the establishment of ECMO in the LPS-treated animals. PFR remained elevated in all animals with no signs of lung recovery. In the human patients, in the two that recovered, PFR decreased. In the two whose lung function deteriorated while on ECMO, there was increased PFR with no sign of recovery in lung function. The present results indicate that real-time monitoring of PFR may be a new, complementary approach in the clinic for measurement of the extent of lung injury and recovery over time in ECMO patients with ARDS.

Extracorporeal Life Support in Hemorrhagic Conditions: A Systematic Review

Extracorporeal life support (ECLS) is indicated in refractory acute respiratory or cardiac failure. According to the need for anticoagulation, bleeding conditions (e.g., in trauma, pulmonary bleeding) have been considered a contraindication for the use of ECLS. However, there is increasing evidence for improved outcomes after ECLS support in hemorrhagic patients based on the benefits of hemodynamic support outweighing the increased risk of bleeding. We conducted a systematic literature search according to the PRISMA guidelines and reviewed publications describing ECLS support in hemorrhagic conditions. Seventy-four case reports, four case series, seven retrospective database observational studies, and one preliminary result of an ongoing study were reviewed. In total, 181 patients were identified in total of 86 manuscripts. The reports included patients suffering from bleeding caused by pulmonary hemorrhage (n = 53), trauma (n = 96), postpulmonary endarterectomy (n = 13), tracheal bleeding (n = 1), postpartum or cesarean delivery (n = 11), and intracranial hemorrhage (n = 7). Lower targeted titration of heparin infusion, heparin-free ECLS until coagulation is normalized, clamping of the endotracheal tube, and other ad hoc possibilities represent potential beneficial maneuvers in such conditions. Once the patient is cannulated and circulation restored, bleeding control surgery is performed for stabilization if indicated. The use of ECLS for temporary circulatory or respiratory support in critical patients with refractory hemorrhagic shock appears feasible considering tailored ECMO management strategies. Further investigation is needed to better elucidate the patient selection and ECLS management approaches.

Extracorporeal support for trauma: A trauma quality improvement project (TQIP) analysis in patients with acute respiratory distress syndrome

INTRODUCTION

The use of extracorporeal membrane oxygenation (ECMO) in trauma patients with severe acute respiratory distress syndrome (ARDS) continues to evolve. The objective of this study was to perform a comparative analysis of trauma patients with ARDS who received ECMO to a propensity matched cohort of patients who underwent conventional management.

METHODS

The Trauma Quality Improvement Program (TQIP) database was queried from 2013 to 2016 for all patients with ARDS and those who received ECMO. Demographics, as well as clinical, injury, intervention, and outcome data were collected and analyzed. Patients with ARDS were divided into two groups, those who received ECMO and those who did not. A propensity score analysis was performed using the following criteria: age, gender, vital signs (HR, SBP) and GCS on admission, Injury Severity Score (ISS), and Abbreviated Injury Scale (AIS) score in several body regions. Outcomes between the groups were subsequently compared using univariate as well as Cox regression analyses. Secondary outcomes such as hospitalization (HLOS), ICU length-of-stay (LOS) and ventilation days stratified for patient demographics, timing of ECMO and anticoagulation status were compared.

RESULTS

Over the 3-year study period, 8990 patients with ARDS were identified from the TQIP registry. Following exclusion, 3680 were included in the final analysis, of which 97 (2.6%) received ECMO. On univariate analysis following matching, patients who underwent ECMO had lower overall hospital mortality (23 vs 50%, p < 0.001) with higher rates of complications (p < 0.005), including longer HLOS. In those undergoing ECMO, early initiation (<7 days) was associated with shorter HLOS, ICU LOS, and fewer ventilator days. No difference was observed between the two groups with regard to anticoagulation.

CONCLUSION

Extracorporeal membrane oxygenation use in trauma patients with ARDS may be associated with improved survival, especially for young patients with thoracic injuries, early in the course of ARDS. Anticoagulation while on circuit was not associated with increased risk of hemorrhage or mortality, even in the setting of head injuries. The mortality benefit suggested with ECMO comes at the expense of a potential increase in complication rate and prolonged hospitalization.

The Roles of Membrane Technology in Artificial Organs: Current Challenges and Perspectives

The recent outbreak of the COVID-19 pandemic in 2020 reasserted the necessity of artificial lung membrane technology to treat patients with acute lung failure. In addition, the aging world population inevitably leads to higher demand for better artificial organ (AO) devices. Membrane technology is the central component in many of the AO devices including lung, kidney, liver and pancreas. Although AO technology has improved significantly in the past few decades, the quality of life of organ failure patients is still poor and the technology must be improved further. Most of the current AO literature focuses on the treatment and the clinical use of AO, while the research on the membrane development aspect of AO is relatively scarce. One of the speculated reasons is the wide interdisciplinary spectrum of AO technology, ranging from biotechnology to polymer chemistry and process engineering. In this review, in order to facilitate the membrane aspects of the AO research, the roles of membrane technology in the AO devices, along with the current challenges, are summarized. This review shows that there is a clear need for better membranes in terms of biocompatibility, permselectivity, module design, and process configuration.

Mechanical ventilation in patients with acute brain injury: recommendations of the European Society of Intensive Care Medicine consensus

Purpose

To provide clinical practice recommendations and generate a research agenda on mechanical ventilation and respiratory support in patients with acute brain injury (ABI).

Methods

An international consensus panel was convened including 29 clinician-scientists in intensive care medicine with expertise in acute respiratory failure, neurointensive care, or both, and two non-voting methodologists. The panel was divided into seven subgroups, each addressing a predefined clinical practice domain relevant to patients admitted to the intensive care unit (ICU) with ABI, defined as acute traumatic brain or cerebrovascular injury. The panel conducted systematic searches and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) method was used to evaluate evidence and formulate questions. A modified Delphi process was implemented with four rounds of voting in which panellists were asked to respond to questions (rounds 1–3) and then recommendation statements (final round). Strong recommendation, weak recommendation, or no recommendation were defined when > 85%, 75–85%, and < 75% of panellists, respectively, agreed with a statement.

Results

The GRADE rating was low, very low, or absent across domains. The consensus produced 36 statements (19 strong recommendations, 6 weak recommendations, 11 no recommendation) regarding airway management, non-invasive respiratory support, strategies for mechanical ventilation, rescue interventions for respiratory failure, ventilator liberation, and tracheostomy in brain-injured patients. Several knowledge gaps were identified to inform future research efforts.

Conclusions

This consensus provides guidance for the care of patients admitted to the ICU with ABI. Evidence was generally insufficient or lacking, and research is needed to demonstrate the feasibility, safety, and efficacy of different management approaches.

Electronic supplementary material

The online version of this article (10.1007/s00134-020-06283-0) contains supplementary material, which is available to authorized users.

Extracorporeal membrane oxygenation use in Trauma Quality Improvement Program centers: Temporal trends and future directions

BACKGROUND

Increased clinical experience and the decreased need for systemic anticoagulation have renewed interest in the use of extracorporeal membrane oxygenation (ECMO) for posttraumatic respiratory and cardiopulmonary failure. The objectives of this study were to describe the incidence and temporal trends of ECMO use at trauma centers, the outcomes of trauma patients undergoing ECMO, and the characteristics of trauma centers providing ECMO.

METHODS

Data were derived from the American College of Surgeons Trauma Quality Improvement Program data set. We included adults with at least one severe injury admitted to a level I or II trauma center between 2012 and 2016 who received at least 1 day of mechanical ventilation. Patients were categorized based on whether or not they received ECMO during their admission. The primary outcome was change in the incidence of ECMO across study years. We also evaluated patient outcomes and variation in ECMO volumes across centers.

RESULTS

Of 194,314 severely injured patients undergoing mechanical ventilation across 450 centers, 269 (0.14%) received ECMO. Extracorporeal membrane oxygenation patients had significantly higher mortality than non-ECMO patients (32% vs. 19%). The standardized rate of ECMO from 2012 to 2016 increased significantly from 75.2 to 179.0 cases per 100,000 severely injured patients undergoing mechanical ventilation. The average annual growth rate was 24%. Of the 82 centers(18%) reporting at least 1 ECMO trauma case, 34 (41%) reported only a single case.

CONCLUSION

The use of ECMO for trauma, although rare, is rapidly increasing. Two thirds of patients who receive ECMO following traumatic injury survive their hospitalization. These data suggest that ECMO represents a potential treatment strategy for trauma patients with respiratory or cardiopulmonary failure. However, given the rarity of the procedure, there exists an opportunity to develop practice guidelines regarding the indications for, and approach to, ECMO in the setting of trauma.

LEVEL OF EVIDENCE

Therapeutic/care management, level IV.

Anticoagulation strategies in extracorporeal circulatory devices in adult populations

Extracorporeal circulatory devices such as hemodialysis and extracorporeal membrane oxygenation can be lifesaving; however, they are also prone to pathologic events including device failure, venous and arterial thrombosis, hemorrhage, and an accelerated risk for atherosclerotic disease due to interactions between blood components and device surfaces of varying biocompatibility. While extracorporeal devices may be used acutely for limited periods of time (eg, extracorporeal membrane oxygenation, continuous venovenous hemofiltration, therapeutic apheresis), some patients require chronic use of these technologies (eg, intermittent hemodialysis and left ventricular assist devices). Given the substantial thrombotic risks associated with extracorporeal devices, multiple antiplatelet and anticoagulation strategies-including unfractionated heparin, low-molecular-weight heparin, citrate, direct thrombin inhibitors, and direct oral anticoagulants, have been used to mitigate the thrombotic milieu within the patient and device. In the following manuscript, we outline the current data on anticoagulation strategies for commonly used extracorporeal circulatory devices, highlighting the potential benefits and complications involved with each.

Extracorporeal membrane oxygenation in trauma patients: a systematic review

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) has evolved considerably over the past two decades and has been gradually utilized in severe trauma. However, the indications for the use of ECMO in trauma remain uncertain and the clinical outcomes are different. We performed a systematic review to provide an overall estimate of the current performance of ECMO in the treatment of trauma patients.

MATERIALS AND METHODS

We searched PubMed and MEDLINE databases up to the end of December 2019 for studies on ECMO in trauma. The PRISMA statement was followed. Data on demographics of the patient, mechanism of injury, injury severity scores (ISS), details of ECMO strategies, and clinical outcome were extracted.

RESULTS

A total of 58 articles (19 retrospective reports and 39 case reports) were deemed eligible and included. In total, 548 patients received ECMO treatment for severe trauma (adult 517; children 31; mean age of adults 34.9 ± 12.3 years). Blunt trauma (85.4%) was the primary injury mechanism, and 128 patients had traumatic brain injury (TBI). The mean ISS was 38.1 ± 15.0. A total of 71.3% of patients were initially treated with VV ECMO, and 24.5% were placed on VA ECMO. The median time on ECMO was 9.6 days, and the median time to ECMO was 5.7 days. A total of 60% of patients received initially heparin anticoagulation. Bleeding (22.9%) and thrombosis (19%) were the most common complications. Ischemia of the lower extremities occurred in 9 patients. The overall hospital mortality was 30.3%.

CONCLUSIONS

ECMO has been gradually utilized in a lifesaving capacity in severe trauma patients, and the feasibility and advantages of this technique are becoming widely accepted. The safety and effectiveness of ECMO in trauma require further study. Several problems with ECMO in trauma, including the role of VA-ECMO, the time to institute ECMO, and the anticoagulation strategy remain controversial and must be solved in future studies.

VENTILatOry strategies in patients with severe traumatic brain injury: the VENTILO Survey of the European Society of Intensive Care Medicine (ESICM)

Background

Severe traumatic brain injury (TBI) patients often develop acute respiratory failure. Optimal ventilator strategies in this setting are not well established. We performed an international survey to investigate the practice in the ventilatory management of TBI patients with and without respiratory failure.

Methods

An electronic questionnaire, including 38 items and 3 different clinical scenarios [arterial partial pressure of oxygen (PaO₂)/inspired fraction of oxygen (FiO₂) > 300 (scenario 1), 150–300 (scenario 2), < 150 (scenario 3)], was available on the European Society of Intensive Care Medicine (ESICM) website between November 2018 and March 2019. The survey was endorsed by ESICM.

Results

There were 687 respondents [472 (69%) from Europe], mainly intensivists [328 (48%)] and anesthesiologists [206 (30%)]. A standard protocol for mechanical ventilation in TBI patients was utilized by 277 (40%) respondents and a specific weaning protocol by 198 (30%). The most common tidal volume (TV) applied was 6–8 ml/kg of predicted body weight (PBW) in scenarios 1–2 (72% PaO₂/FIO₂ > 300 and 61% PaO₂/FiO₂ 150–300) and 4–6 ml/kg/PBW in scenario 3 (53% PaO₂/FiO₂ < 150). The most common level of highest positive end-expiratory pressure (PEEP) used was 15 cmH₂O in patients with a PaO₂/FiO₂ ≤ 300 without intracranial hypertension (41% if PaO₂/FiO₂ 150–300 and 50% if PaO₂/FiO₂ < 150) and 10 cmH₂O in patients with intracranial hypertension (32% if PaO₂/FiO₂ 150–300 and 33% if PaO₂/FiO₂ < 150). Regardless of the presence of intracranial hypertension, the most common carbon dioxide target remained 36–40 mmHg whereas the most common PaO₂ target was 81–100 mmHg in all the 3 scenarios. The most frequent rescue strategies utilized in case of refractory respiratory failure despite conventional ventilator settings were neuromuscular blocking agents [406 (88%)], recruitment manoeuvres [319 (69%)] and prone position [292 (63%)].

Conclusions

Ventilatory management, targets and practice of adult severe TBI patients with and without respiratory failure are widely different among centres. These findings may be helpful to define future investigations in this topic.

The Feasibility of Venovenous ECMO at Role-2 Facilities in Austere Military Environments

INTRODUCTION

Venovenous extracorporeal membrane oxygenation (VV-ECMO) has been gaining use to bridge the recovery from acute respiratory distress syndrome (ARDS) refractory to conventional treatment. However, these interventions are often limited to higher echelons of military care. We present a case of lung salvage from severe ARDS in an Afghani soldier with VV-ECMO at a Role-2 (R2) facility in an austere military environment in Afghanistan.

CASE

A 25-year-old Afghani soldier presented to an R2 facility with blast lung injury and multiple penetrating injuries following an explosion. The patient underwent immediate damage control laparotomy. The abdomen was left open for subsequent washouts and ongoing resuscitation. Due to his ineligibility for evacuation and worsening ARDS, despite 5 d of conventional ventilation strategies, he was started on VV-ECMO. The patient had immediate improvements in oxygenation, which continued for 10 d. Moreover, he underwent three transportations to the operating room without accidental decannulation or disruption of the VV-ECMO device. Despite significant improvements, the patient expired on postoperative day 15, due to an overwhelming intra-abdominal sepsis.

CONCLUSION

As future advancements are sought, VV-ECMO may become a consideration for casualties with severe ARDS at the point of injury and at lower echelons of military care.

Extracorporeal life support in pediatric trauma: a systematic review

Introduction

Extracorporeal membrane oxygenation (ECMO) was once thought to be contraindicated in trauma patients, however ECMO is now used in adult patients with post-traumatic acute respiratory distress syndrome (ARDS) and multisystem trauma. Despite acceptance as a therapy for the severely injured adult, there is a paucity of evidence supporting ECMO use in pediatric trauma patients.

Methods

An electronic literature search of PubMed, MEDLINE, and the Cochrane Database of Collected Reviews from 1972 to 2018 was performed. Included studies reported on ECMO use after trauma in patients ≤18 years of age and reported outcome data. The Institute of Health Economics quality appraisal tool for case series was used to assess study quality.

Results

From 745 studies, four met inclusion criteria, reporting on 58 pediatric trauma patients. The age range was <1–18 years. Overall study quality was poor with only a single article of adequate quality. Twenty-nine percent of patients were cannulated at adult centers, the remaining at pediatric centers. Ninety-one percent were cannulated for ARDS and the remaining for cardiovascular collapse. Overall 60% of patients survived and the survival rate ranged from 50% to 100%. Seventy-seven percent underwent venoarterial cannulation and the remaining underwent veno-venous cannulation.

Conclusion

ECMO may be a therapeutic option in critically ill pediatric trauma patients. Consideration should be made for the expansion of ECMO utilization in pediatric trauma patients including its application for pediatric patients at adult trauma centers with ECMO capabilities.

Heparin-Sparing Anticoagulation Strategies Are Viable Options for Patients on Veno-Venous ECMO

BACKGROUND

Extracorporeal membrane oxygenation (ECMO), a rescue therapy for pulmonary failure, has traditionally been limited by anticoagulation requirements. Recent practice has challenged the absolute need for anticoagulation, expanding the role of ECMO to patients with higher bleeding risk. We hypothesize that mortality, bleeding, thrombotic events, and transfusions do not differ between heparin-sparing and full therapeutic anticoagulation strategies in veno-venous (VV) ECMO management.

MATERIALS AND METHODS

Adult VV ECMO patients between October 2011 and May 2018 at a single center were reviewed. A heparin-sparing strategy was implemented in October 2014; we compared outcomes in an as-treated fashion. The primary end point was survival. Secondary end points included bleeding, thrombotic complications, and transfusion requirements.

RESULTS

Forty VV ECMO patients were included: 17 (147 circuit-days) before and 23 (214 circuit-days) after implementation of a heparin-sparing protocol. Patients treated with heparin-sparing anticoagulation had a lower body mass index (28.5 ± 7.1 versus 38.1 ± 12.4, P = 0.01), more often required inotropic support before ECMO (82 versus 50%, P = 0.05), and had a lower mean activated clotting time (167 ± 15 versus 189 ± 15 s, P < 0.01). There were no significant differences in survival to decannulation (59 versus 83%, P = 0.16) or discharge (50 versus 72%, P = 0.20), bleeding (32 versus 33%, P = 1.0), thromboembolic events (18 versus 39%, P = 0.17), or transfusion requirements (median 1.1 versus 0.9 unit per circuit-day, P = 0.48).

CONCLUSIONS

Survival, bleeding, thrombotic complications, and transfusion requirements did not differ between heparin-sparing and full therapeutic heparin strategies for management of VV ECMO. VV ECMO can be a safe option in patients with traditional contraindications to anticoagulation.

Pulmonary lobectomy in two multitrauma patients under extracorporeal circulation placed preoperatively in an intensive care unit: A case report

The clinical course of our two patients highlights the feasibility of using venovenous extracorporeal membrane oxygenation (ECMO) with heparin for multitraumatic patients needing thoracic surgery. Further research is required to determine if surgery can be performed with totally heparin-free vv-ECMO. All ICU teams should become familiar with this technique.

Extra corporeal membrane oxygenation in the critical trauma patient

PURPOSE OF REVIEW

The purpose of this review is to describe recent evidence regarding the use of extracorporeal membrane oxygenation (ECMO) as salvage therapy for severe cardiac or respiratory failure in patients with trauma. The characteristics of this cohort of patients, including the risk of bleeding and the need for systemic anticoagulation, are generally considered as relative contraindications to ECMO treatment. However, recent evidence suggests that the use of ECMO should be taken in consideration even in this group of patients.

RECENT FINDINGS

The recent findings suggest that venous-venous ECMO can be feasible in the treatment of refractory respiratory failure and severe acute respiratory distress syndrome trauma-related. The improvement of ECMO techniques including the introduction of centrifugal pumps and heparin-coated circuits are progressively reducing the amount of heparin required; moreover, the application of heparin-free ECMO showed good outcomes and minimal complications. Venous-arterial ECMO has emerged as a salvage intervention in patients with cardiogenic shock and after cardiac arrest. Venous-arterial ECMO provides circulatory support allowing time for other treatments to promote recovery in presence of acute cardiopulmonary failure. Only poor-quality evidence is available, for venous-arterial ECMO in trauma patients.

SUMMARY

ECMO can be considered as a safe rescue therapy even in trauma patients, including neurological injury, chest trauma as well as burns. However, evidence is still poor; further studies are warranted focusing on trauma patients undergoing ECMO, to better clarify the effect on survival, the type and dose of anticoagulation to use, as well as the utility of dedicated multidisciplinary trauma-ECMO units.

Development of zwitterionic sulfobetaine block copolymer conjugation strategies for reduced platelet deposition in respiratory assist devices

Respiratory assist devices, that utilize ∼2 m2 of hollow fiber membranes (HFMs) to achieve desired gas transfer rates, have been limited in their adoption due to such blood biocompatibility limitations. This study reports two techniques for the functionalization and subsequent conjugation of zwitterionic sulfobetaine (SB) block copolymers to polymethylpentene (PMP) HFM surfaces with the intention of reducing thrombus formation in respiratory assist devices. Amine or hydroxyl functionalization of PMP HFMs (PMP-A or PMP-H) was accomplished using plasma-enhanced chemical vapor deposition. The generated functional groups were conjugated to low molecular weight SB block copolymers with N-hydroxysuccinimide ester or siloxane groups (SBNHS or SBNHSi) that were synthesized using reversible addition fragmentation chain transfer polymerization. The modified HFMs (PMP-A-SBNHS or PMP-H-SBNHSi) showed 80-95% reduction in platelet deposition from whole ovine blood, stability under the fluid shear of anticipated operating conditions, and uninhibited gas exchange performance relative to non-modified HFMs (PMP-C). Additionally, the functionalization and SBNHSi conjugation technique was shown to reduce platelet deposition on polycarbonate and poly(vinyl chloride), two other materials commonly found in extracorporeal circuits. The observed thromboresistance and stability of the SB modified surfaces, without degradation of HFM gas transfer performance, indicate that this approach is promising for longer term pre-clinical testing in respiratory assist devices and may ultimately allow for the reduction of anticoagulation levels in patients being supported for extended periods. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2681-2692, 2018.

Extracorporeal membrane oxygenation in trauma: A single institution experience and review of the literature

INTRODUCTION:

Limited options exist for cardiovascular support of the trauma patient in extremis. This patient population offers challenges that are often considered insurmountable. This article identifies a heterogeneous group of trauma patients in extremis who may benefit from extracorporeal membrane oxygenation.

METHODS:

Data were sourced from the medical records of all patients placed on extracorporeal membrane oxygenation following trauma at a Level I Trauma Center between 1 December 2016 and 1 December 2017.

RESULTS:

All patients were male (N = 7), mostly with blunt injuries (n = 5), with an average age of 41 years and with an average Injury Severity Scores of 33 (median = 34). Two out of seven patients survived (28.5%). Survivors tended to have a longer duration on extracorporeal membrane oxygenation (13.5 vs 3.8 days), had extracorporeal membrane oxygenation initiated later (15 vs 7.8 days), and had suffered a blunt injury. Two patients were initiated on veno-arterial extracorporeal membrane oxygenation (both non-survivors) and five were initiated on veno-venous extracorporeal membrane oxygenation (two survivors, three non-survivors). Five patients were heparinized immediately (one survivor, four non-survivors), and two patients were heparinized after clotting was noted in the circuit (one survivor, one non-survivor). Three of the seven (42.8%) patients suffered cardiac arrest either prior to, or during, the initiation of extracorporeal membrane oxygenation (all non-survivors).

DISCUSSION:

Extracorporeal membrane oxygenation use in the trauma patient in extremis is not standard; however, this article demonstrates that extracorporeal membrane oxygenation is feasible in a complex, heterogeneous patient population when treated at designated centers.

The Impact of an Advanced ECMO Program on Traumatically Injured Patients

In June 2016, an advanced extracorporeal membrane oxygenation (ECMO) program consisting of a multidisciplinary team was initiated at a large level-one trauma center. The program was created to standardize management for patients with a wide variety of pathologies, including trauma. This study evaluated the impact of the advanced ECMO program on the outcomes of traumatically injured patients undergoing ECMO. A retrospective cohort study was performed on all patients sustaining traumatic injury who required ECMO support from January 2014 to September 2017. The primary outcome was to determine survival in trauma ECMO patients in the two timeframes, before and after initiation of the advanced ECMO program. Secondary outcomes included complication rates, length of stay, ventilator usage, and ECMO days. One hundred and thirty eight patients were treated with ECMO during the study period. Of the 138 patients, 22 sustained traumatic injury. Seven patients were treated in our pre-group and 15 in our post-group. The majority of patients were treated with VV ECMO. Our post group VV ECMO extracorporeal survival rate was 64% and our survival to discharge was 55%. This study demonstrated an improvement in survival after implementation of our advanced ECMO program. The implementation of a multidisciplinary trauma ECMO team dedicated to the rescue of critically ill patients is the key for achieving excellent outcomes in the trauma population.

Predictors of hospital mortality in adult trauma patients receiving extracorporeal membrane oxygenation for advanced life support: a retrospective cohort study

Background

Using extracorporeal membrane oxygenation (ECMO) to provide advanced life support in adult trauma patients remains a controversial issue now. The study was aimed at identifying the independent predictors of hospital mortality in adult trauma patients receiving ECMO for advanced cardiopulmonary dysfunctions.

Methods

This retrospective study enrolled 36 adult trauma patients receiving ECMO due to advanced shock or respiratory failure in a level I trauma center between August 2006 and October 2014. Variables collected for analysis were demographics, serum biomarkers, characteristics of trauma, injury severity score (ISS), damage-control interventions, indications of ECMO, and associated complications. The outcomes were hospital mortality and hemorrhage on ECMO. The multivariate logistic regression method was used to identify the independent prognostic predictors for the outcomes.

Results

The medians of age and ISS were 36 (27–49) years and 29 (19–45). Twenty-three patients received damage-control interventions before ECMO. Among the 36 trauma patients, 14 received ECMO due to shock and 22 for respiratory failure. The complications of ECMO are major hemorrhages (n = 12), acute renal failure requiring hemodialysis (n = 10), and major brain events (n = 7). There were 15 patients died in hospital, and 9 of them were in the shock group.

Conclusions

The severity of trauma and the type of cardiopulmonary dysfunction significantly affected the outcomes of ECMO used for sustaining patients with post-traumatic cardiopulmonary dysfunction. Hemorrhage on ECMO remained a concern while the device was required soon after trauma, although a heparin-minimized protocol was adopted.

Trial registration

This study reported a health care intervention on human participants and was retrospectively registered. The Chang Gung Medical Foundation Institutional Review Board approved the study (no. 201601610B0) on December 12, 2016. All of the data were extracted from December 14, 2016, to March 31, 2017.

Acute respiratory distress syndrome in traumatic brain injury: how do we manage it?

Traumatic brain injury (TBI) is an important cause of morbidity and mortality worldwide. TBI patients frequently suffer from lung complications and acute respiratory distress syndrome (ARDS), which is associated with poor clinical outcomes. Moreover, the association between TBI and ARDS in trauma patients is well recognized. Mechanical ventilation of patients with a concomitance of acute brain injury and lung injury can present significant challenges. Frequently, guidelines recommending management strategies for patients with traumatic brain injuries come into conflict with what is now considered best ventilator practice. In this review, we will explore the strategies of the best practice in the ventilatory management of patients with ARDS and TBI, concentrating on those areas in which a conflict exists. We will discuss the use of ventilator strategies such as protective ventilation, high positive end expiratory pressure (PEEP), prone position, recruitment maneuvers (RMs), as well as techniques which at present are used for 'rescue' in ARDS (including extracorporeal membrane oxygenation) in patients with TBI. Furthermore, general principles of fluid, haemodynamic and hemoglobin management will be discussed. Currently, there are inadequate data addressing the safety or efficacy of ventilator strategies used in ARDS in adult patients with TBI. At present, choice of ventilator rescue strategies is best decided on a case-by-case basis in conjunction with local expertise.