Extracorporeal membrane oxygenation during pregnancy and peripartal. An international retrospective multicenter study

INTRODUCTION

Extracorporeal Membrane Oxygenation (ECMO) may be used in the setting of pregnancy or the peripartal period, however its utility has not been well-characterized. This study aims to give an overview on the prevalence of peripartel ECMO cases and further assess the indications and outcomes of ECMO in this setting across multiple centers and countries.

METHODS

A retrospective, multicenter, international cohort study of pregnant and peripartum ECMO cases was performed. Data were collected from six ECMO centers across three continents over a 10-year period.

RESULTS

A total of 60 pregnany/peripartal ECMO cases have been identified. Most frequent indications are acute respiratory distress syndrome (n = 30) and pulmonary embolism (n = 5). Veno-venous ECMO mode was applied more often (77%). ECMO treatment during pregnancy was performed in 17 cases. Maternal and fetal survival was high with 87% (n = 52), respectively 73% (n = 44).

CONCLUSIONS

Various emergency scenarios during pregnancy and at time of delivery may require ECMO treatment. Peripartal mortality in a well-resourced setting is rare, however emergencies in the labor room occur and knowledge of available rescue therapy is essential to improve outcome. Obstetricians and obstetric anesthesiologists should be aware of the availability of ECMO resource at their hospital or region to ensure immediate contact when needed.

Extracorporeal cardiopulmonary resuscitation for refractory in-hospital cardiac arrest: A retrospective cohort study

BACKGROUND

Extracorporeal cardiopulmonary resuscitation (ECPR) is a rescue therapy for refractory cardiac arrest, but its high mortality has raised questions about patient selection. No selection criteria have been proposed for patients experiencing in-hospital cardiac arrest. We aimed to identify selection criteria available at the time ECPR was considered for patients with in-hospital cardiac arrest. We analyzed data of in-hospital cardiac arrest patients undergoing ECPR in our extracorporeal membrane oxygenation (ECMO) center (March 2007 to March 2019). Intensive care unit (ICU) and 1-year survival post-hospital discharge were assessed. Factors associated with ICU survival before ECPR were investigated. An external validation cohort from a previous multicenter study was used to validate our results.

RESULTS

Among the 137 patients (67.9% men; median [IQR] age, 54 [43-62] years; low-flow duration, 45 [30-70] min) requiring ECPR, 32.1% were weaned-off ECMO. Their respective ICU- and 1-year survival rates were 21.9% and 19%. Most 1-year survivors had favorable neurological outcomes (cerebral performance category score 1 or 2). ICU survivors compared to nonsurvivors, respectively, were more likely to have a shockable initial rhythm (53.3% versus 24.3%; P < 0.01), a shorter median (IQR) low-flow time (30 (25-53) versus 50 (35-80) min, P < 0.01) and they more frequently underwent a subsequent intervention (63.3% versus 26.2%, P < 0.01). The algorithm obtained by combining age, initial rhythm and low-flow duration discriminated between patient groups with very different survival probabilities in the derivation and validation cohorts.

CONCLUSION

Survival of ECPR-managed in-hospital cardiac arrest patients in this cohort was poor but hospital survivors' 1-year neurological outcomes were favorable. When deciding whether or not to use ECPR, the combination of age, initial rhythm and low-flow duration can improve patient selection.

Predictors of poor outcome after extra-corporeal membrane oxygenation for refractory cardiac arrest (ECPR): A post hoc analysis of a multicenter database

BACKGROUND

The objective was to assess predictors for unfavorable neurological outcome (UO) in out-of-hospital (OHCA) and in-hospital (IHCA) cardiac arrest patients treated with Extracorporeal cardiopulmonary resuscitation (ECPR).

METHODS

A post hoc analysis of retrospective data from five European ECPR centers (January 2012-December 2016) was performed. The primary composite endpoint was 3-month UO defined as survival with a cerebral performance category (CPC) of 3-4 or death (CPC 5).

RESULTS

A total of 413 patients treated with ECPR were included (median age was 57 [48-65] years, male gender 78%): 61% of patients (n = 250) suffered OHCA. The median time from collapse to ECMO placement was 63 [45-82] minutes. Overall, 81% patients (n = 333) showed unfavorable UO, which was higher in OHCA patients (90% vs 66%), as compared to IHCA. In OHCA, prolonged time from collapse to ECMO initiation (OR 1.02, p < 0.01) and higher ECMO blood flow (OR 1.99, p = 0.01) were associated with UO while initial shockable rhythm (OR 0.04, p < 0.01), previous heart disease (OR 0.20, p < 0.01) and pre-hospital hypothermia (OR 0.08, p < 0.01) had a protective role. In IHCA, prolonged time from arrest to ECMO implantation (OR 1.02, p = 0.03), high lactate level on admission (OR 1.15, p < 0.01) and higher body weight (OR 1.03, p < 0.01) were independently associated with UO.

CONCLUSIONS

IHCA and OHCA patients receiving ECPR have different predictors of UO at presentation, suggesting that selection criteria for ECPR should be decided according to the location of CA. After ECMO initiation, ECMO blood flow management and mean arterial pressure targets might also impact neurological recovery.

Understanding the "extracorporeal membrane oxygenation gap" in veno-arterial configuration for adult patients: Timing and causes of death

Timing and causes of hospital mortality in adult patients undergoing veno‐arterial extracorporeal membrane oxygenation (V‐A ECMO) have been poorly described. Aim of the current review was to investigate the timing and causes of death of adult patients supported with V‐A ECMO and subsequently define the “V‐A ECMO gap,” which represents the patients who are successfully weaned of ECMO but eventually die during hospital stay. A systematic search was performed using electronic MEDLINE and EMBASE databases through PubMed. Studies reporting on adult V‐A ECMO patients from January 1993 to December 2020 were screened. The studies included in this review were studies that reported more than 10 adult, human patients, and no mechanical circulatory support other than V‐A ECMO. Information extracted from each study included mainly mortality and causes of death on ECMO and after weaning. Complications and discharge rates were also extracted. Sixty studies with 9181 patients were included for analysis in this systematic review. Overall mortality was 38.0% (95% confidence intervals [CIs] 34.2%‐41.9%) during V‐A ECMO support (reported by 60 studies) and 15.3% (95% CI 11.1%‐19.5%, reported by 57 studies) after weaning. Finally, 44.0% of patients (95% CI 39.8‐52.2) were discharged from hospital (reported by 60 studies). Most common causes of death on ECMO were multiple organ failure, followed by cardiac failure and neurological causes. More than one‐third of V‐A ECMO patients die during ECMO support. Additionally, many of successfully weaned patients still decease during hospital stay, defining the “V‐A ECMO gap.” Underreporting and lack of uniformity in reporting of important parameters remains problematic in ECMO research. Future studies should uniformly define timing and causes of death in V‐A ECMO patients to better understand the effectiveness and complications of this support.

Ex vivo models for research in extracorporeal membrane oxygenation: a systematic review of the literature

With ongoing progress of components of extracorporeal membrane oxygenation including improvements of oxygenators, pumps, and coating materials, extracorporeal membrane oxygenation became increasingly accepted in the clinical practice. A suitable testing in an adequate setup is essential for the development of new technical aspects. Relevant tests can be conducted in ex vivo models specifically designed to test certain aspects. Different setups have been used in the past for specific research questions. We conducted a systematic literature review of ex vivo models of extracorporeal membrane oxygenation components. MEDLINE and Embase were searched between January 1996 and October 2017. The inclusion criteria were ex vivo models including features of extracorporeal membrane oxygenation technology. The exclusion criteria were clinical studies, abstracts, studies in which the model of extracorporeal membrane oxygenation has been reported previously, and studies not reporting on extracorporeal membrane oxygenation components. A total of 50 studies reporting on different ex vivo extracorporeal membrane oxygenation models have been identified from the literature search. Models have been grouped according to the specific research question they were designed to test for. The groups are focused on oxygenator performance, pump performance, hemostasis, and pharmacokinetics. Pre-clinical testing including use of ex vivo models is an important step in the development and improvement of extracorporeal membrane oxygenation components and materials. Furthermore, ex vivo models offer valuable insights for clinicians to better understand the consequences of choice of components, setup, and management of an extracorporeal membrane oxygenation circuit in any given condition. There is a need to standardize the reporting of pre-clinical studies in this area and to develop best practice in their design.

Incidence of early intra-cranial bleeding and ischaemia in adult veno-arterial extracorporeal membrane oxygenation and extracorporeal cardiopulmonary resuscitation patients: a retrospective analysis of risk factors

BACKGROUND

Cerebral complications in veno-arterial extracorporeal membrane oxygenation are known to have a strong impact on mortality and morbidity. Aim of this study is to investigate the early incidence, risk factors and in-hospital mortality of intra-cranial ischaemia and haemorrhage in adults undergoing veno-arterial extracorporeal membrane oxygenation treatment.

METHODS

This study is a single-centre retrospective analysis on adult patients undergoing veno-arterial extracorporeal membrane oxygenation for different indications. The inclusion criterion included patients with early routine cerebral computed tomography imaging during extracorporeal membrane oxygenation, with no clinical evidence of cerebral pathology prior to cannulation. Cerebral complications were grouped by aetiology and the territories of the brain's supplying arteries.

RESULTS

One hundred eighty-seven adult patients with a total of 190 veno-arterial extracorporeal membrane oxygenation treatments were included. A total of 16.3% (n = 31) had evidence of either cerebral ischaemia (11.1%) or haemorrhage (5.8%); one patient suffered from both. Cerebral computed tomography scans were performed early in median on the first day after extracorporeal membrane oxygenation cannulation; in-hospital mortality of intra-cranial ischaemia and haemorrhage was 71.4% and 45.5%, respectively. Associated with an increased risk for ischaemic lesions were cannulation of the ascending aorta, higher age, presence of an autoimmune disease and cardiac surgery prior to veno-arterial extracorporeal membrane oxygenation. An association with haemorrhagic lesions was found for a lower blood PaCO₂ at 2 hours, lower blood flow through the extracorporeal membrane oxygenation device at 2 hours, higher international normalized ratio and constantly higher activated partial thromboplastin time values as well as higher mean arterial pressures until haemorrhagic lesions were evident.

CONCLUSION

Cerebral complications are frequent in patients on veno-arterial extracorporeal membrane oxygenation and may be clinically silent events. Careful monitoring with routine neuroimaging seems to be the most appropriate diagnostic approach at present. Intra-cranial ischaemia occurs more frequent than haemorrhage and is associated with cannulation of the aorta ascendens.

Piloting an ICU follow-up clinic to improve health-related quality of life in ICU survivors after a prolonged intensive care stay (PINA): study protocol for a pilot randomised controlled trial

Background

Intensive care unit (ICU) survivors often suffer from cognitive, physical and mental impairments, known as post-intensive care syndrome (PICS). ICU follow-up clinics may improve aftercare of these patients. There is a lack of evidence whether or which concept of an ICU follow-up clinic is effective. Within the PINA study, a concept for an ICU follow-up clinic was developed and will be tested in a pilot randomised controlled trial (RCT), primarily to evaluate the feasibility and additionally the potential efficacy.

Methods/design

Design: Pilot RCT with intervention and control (usual care) arms plus mixed-methods process evaluation. Participants: 100 ICU patients (50 per arm) of three ICUs in a university hospital (Regensburg, Germany), ≥ 18 years with an ICU stay of > 5 days, a sequential organ failure assessment (SOFA) score > 5 during the ICU stay and a life expectancy of more than 6 months.

Intervention: The intervention will contain three components: information, consultation and networking. Information will be available in form of an intensive care guide for patients and next of kin at the ICU and phone support during follow-up. For consultation, patients will visit the ICU follow-up clinic at least once during the first 6 months after discharge from ICU. During these visits, patients will be screened for symptoms of PICS and, if required, referred to specialists for further treatment. The networking part (e.g. special referral letter from the ICU follow-up clinic) aims to provide a network of outpatient care providers for former ICU patients. Feasibility Outcomes: Qualitative and quantitative evaluation will be used to explore reasons for non-participation and the intervention´s acceptability to patients and caregivers. Efficacy Outcomes: Health-related quality of life (HRQOL) will be assessed as primary outcome by the physical component score (PCS) of the Short-Form 12 Questionnaire (SF-12). Secondary outcomes encompass further patient-reported outcomes. All outcomes are assessed at 6 months after discharge from ICU.

Discussion

The PINA study will determine feasibility and potential efficacy of a complex intervention in a pilot RCT to enhance follow-up care of ICU survivors. The pilot study is an important step for further studies in the field of ICU aftercare and especially for the implementation of a pragmatic multi-centre RCT.

Trial registration

ClinicalTrials.gov, NCT04186468. Submitted 2 December 2019

Supplementary Information

The online version contains supplementary material available at 10.1186/s40814-021-00796-1.

ECMO in COVID-19-prolonged therapy needed? A retrospective analysis of outcome and prognostic factors

BACKGROUND

The role of venovenous extracorporeal membrane oxygenation (VV ECMO) in patients with COVID-19-induced acute respiratory distress syndrome (ARDS) still remains unclear. Our aim was to investigate the clinical course and outcome of those patients and to identify factors associated with the need for prolonged ECMO therapy.

METHODS

A retrospective single-center study on patients with VV ECMO for COVID-19-associated ARDS was performed. Baseline characteristics, ventilatory and ECMO parameters, and laboratory and virological results were evaluated over time. Six months follow-up was assessed.

RESULTS

Eleven of 16 patients (68.8%) survived to 6 months follow-up with four patients requiring short-term (<28 days) and seven requiring prolonged (⩾28 days) ECMO support. Lung compliance before ECMO was higher in the prolonged than in the short-term group (28.1 (28.8-32.1) ml/cmH₂O vs 18.7 (17.7-25.0) ml/cmH₂O, p = 0.030). Mechanical ventilation before ECMO was longer (19 (16-23) days vs 5 (5-9) days, p = 0.002) and SOFA score was higher (12.0 (10.5-17.0) vs 10.0 (9.0-10.0), p = 0.002) in non-survivors compared to survivors. Low viral load during the first days on ECMO tended to indicate worse outcomes. Seroconversion against SARS-CoV-2 occurred in all patients, but did not affect outcome.

CONCLUSIONS

VV ECMO support for COVID-19-induced ARDS is justified if initiated early and at an experienced ECMO center. Prolonged ECMO therapy might be required in those patients. Although no relevant predictive factors for the duration of ECMO support were found, the decision to stop therapy should not be made dependent of the length of ECMO treatment.

ECMO in COVID-19-prolonged therapy needed? A retrospective analysis of outcome and prognostic factors

Background:

The role of venovenous extracorporeal membrane oxygenation (VV ECMO) in patients with COVID-19-induced acute respiratory distress syndrome (ARDS) still remains unclear. Our aim was to investigate the clinical course and outcome of those patients and to identify factors associated with the need for prolonged ECMO therapy.

Methods:

A retrospective single-center study on patients with VV ECMO for COVID-19-associated ARDS was performed. Baseline characteristics, ventilatory and ECMO parameters, and laboratory and virological results were evaluated over time. Six months follow-up was assessed.

Results:

Eleven of 16 patients (68.8%) survived to 6 months follow-up with four patients requiring short-term (<28 days) and seven requiring prolonged (⩾28 days) ECMO support. Lung compliance before ECMO was higher in the prolonged than in the short-term group (28.1 (28.8–32.1) ml/cmH₂O vs 18.7 (17.7–25.0) ml/cmH₂O, p = 0.030). Mechanical ventilation before ECMO was longer (19 (16–23) days vs 5 (5–9) days, p = 0.002) and SOFA score was higher (12.0 (10.5–17.0) vs 10.0 (9.0–10.0), p = 0.002) in non-survivors compared to survivors. Low viral load during the first days on ECMO tended to indicate worse outcomes. Seroconversion against SARS-CoV-2 occurred in all patients, but did not affect outcome.

Conclusions:

VV ECMO support for COVID-19-induced ARDS is justified if initiated early and at an experienced ECMO center. Prolonged ECMO therapy might be required in those patients. Although no relevant predictive factors for the duration of ECMO support were found, the decision to stop therapy should not be made dependent of the length of ECMO treatment.

Nocturnal hypoxemic burden during positive airway pressure treatment across different central sleep apnea etiologies

INTRODUCTION

Nocturnal hypoxemia is associated with increased cardiovascular mortality. Here, we assess whether positive airway pressure by adaptive servo-ventilation (ASV) reduces nocturnal hypoxemic burden in patients with primary central sleep apnea (primary CSA), or heart failure related central sleep apnea (CSA-HF) and treatment emergent central sleep apnea (TECSA).

METHODS

Overnight oximetry data from 328 consecutive patients who underwent ASV initiation between March 2010 and May 2018 were retrospectively analyzed. Patients were stratified into three groups: primary CSA (n = 14), CSA-HF (n = 31), TECSA (n = 129). Apnea hypopnea index (AHI) and time spent below 90% SpO₂ (T90) was measured. Additionally, T90 due to acute episodic desaturations (T90_Desaturation) and due to non-specific and non-cyclic drifts of SpO₂ (T90_Non-specific) were assessed.

RESULTS

ASV reduced the AHI below 15/h in all groups. ASV treatment significantly shortened T90 in all three etiologies to a similar extent. T90_Desaturation, but not T90_Non-specific, was reduced by ASV across all three patient groups. AHI was identified as an independent modulator for ΔT90_Desaturation upon ASV treatment (B (95% CI: -1.32 (-1.73; -0.91), p < 0.001), but not for ΔT90 or ΔT90_Non-specific. Body mass index was one independent predictor of T90.

CONCLUSIONS

Across different central sleep apnea etiologies, ASV reduced AHI, but nocturnal hypoxemic burden remained high due to a non-specific component of T90 not related to episodic desaturation. Whether adjunct risk factor management such as weight-loss can further reduce T90 warrants further study.

Mechanical Power during Veno-Venous Extracorporeal Membrane Oxygenation Initiation: A Pilot-Study

Mechanical power (MP) represents a useful parameter to describe and quantify the forces applied to the lungs during mechanical ventilation (MV). In this multi-center, prospective, observational study, we analyzed MP variations following MV adjustments after veno-venous extra-corporeal membrane oxygenation (VV ECMO) initiation. We also investigated whether the MV parameters (including MP) in the early phases of VV ECMO run may be related to the intensive care unit (ICU) mortality. Thirty-five patients with severe acute respiratory distress syndrome were prospectively enrolled and analyzed. After VV ECMO initiation, we observed a significant decrease in median MP (32.4 vs. 8.2 J/min, p < 0.001), plateau pressure (27 vs. 21 cmH₂O, p = 0.012), driving pressure (11 vs. 8 cmH₂O, p = 0.014), respiratory rate (RR, 22 vs. 14 breaths/min, p < 0.001), and tidal volume adjusted to patient ideal body weight (V_T/IBW, 5.5 vs. 4.0 mL/kg, p = 0.001) values. During the early phase of ECMO run, RR (17 vs. 13 breaths/min, p = 0.003) was significantly higher, while positive end-expiratory pressure (10 vs. 14 cmH₂O, p = 0.048) and V_T/IBW (3.0 vs. 4.0 mL/kg, p = 0.028) were lower in ICU non-survivors, when compared to the survivors. The observed decrease in MP after ECMO initiation did not influence ICU outcome. Waiting for large studies assessing the role of these parameters in VV ECMO patients, RR and MP monitoring should not be underrated during ECMO.

Assessing potential for aortoiliac vascular injury from venoarterial extracorporeal membrane oxygenation cannulae: An in vitro particle image velocimetry study

Limb ischemia is a major complication associated with peripheral venoarterial extracorporeal membrane oxygenation (VA-ECMO). The high velocity jet from arterial cannulae can cause "sandblasting" injuries to the arterial endothelium, with the potential risk of distal embolization and end organ damage. The aim of this study was to identify, for a range of clinically relevant VA-ECMO cannulae and flow rates, any regions of peak flow velocity on the aortic wall which may predispose to vascular injury, and any regions of low-velocity flow which may predispose to thrombus formation. A silicone model of the aortic and iliac vessels was sourced and the right external iliac artery was cannulated. Cannulae ranged from 15 to 21 Fr in size. Simulated steady state ECMO flow rates were instituted using a magnetically levitated pump (CentriMag pump). Adaptive particle image velocimetry was performed for each cannula at 3, 3.5, 4, and 4.5 L/min. For all cannulae, in both horizontal and vertical side hole orientations, the peak velocity on the aortic wall ranged from 0.3 to 0.45 m/s, and the regions of lowest velocity flow were 0.05 m/s. The magnitude of peak velocity flow on the aortic wall was not different between a single pair versus multiple pairs of side holes. Maximum velocity flow on the aortic wall occurred earlier at a lower pump flow rate in the vertical orientation of distal side holes compared to a horizontal position. The presence of multiple paired side holes was associated with fewer low-velocity flow regions, and some retrograde flow, in the distal abdominal aorta compared to cannulae with a single pair of side holes. From this in vitro visualization study, the selection of a cannula design with multiple versus single pairs of side holes did not change the magnitude of peak velocity flow delivered to the vessel wall. Cannulae with multiple side holes were associated with fewer regions of low-velocity flow in the distal abdominal aorta. Further in vivo studies, and ideally clinical data would be required to assess any correlation of peak velocity flows with incidence of vascular injury, and any low-velocity flow regions with incidence of thrombosis.

Pressure and flow properties of cannulae for extracorporeal membrane oxygenation II: drainage (venous) cannulae

The use of extracorporeal life support devices such as extracorporeal membrane oxygenation in adults requires cannulation of the patient's vessels with comparatively large diameter cannulae to allow circulation of large volumes of blood (>5 L/min). The cannula diameter and length are the major determinants for extracorporeal membrane oxygenation flow. Manufacturing companies present pressure-flow charts for the cannulae; however, these tests are performed with water. Aims of this study were 1. to investigate the specified pressure-flow charts obtained when using human blood as the circulating medium and 2. to support extracorporeal membrane oxygenation providers with pressure-flow data for correct choice of the cannula to reach an optimal flow with optimal hydrodynamic performance. Eighteen extracorporeal membrane oxygenation drainage cannulae, donated by the manufacturers (n = 6), were studied in a centrifugal pump driven mock loop. Pressure-flow properties and cannula features were described. The results showed that when blood with a hematocrit of 27% was used, the drainage pressure was consistently higher for a given flow (range 10%-350%) than when water was used (data from each respective manufacturer's product information). It is concluded that the information provided by manufacturers in line with regulatory guidelines does not correspond to clinical performance and therefore may not provide the best guidance for clinicians.

The ELSO Maastricht Treaty for ECLS Nomenclature: abbreviations for cannulation configuration in extracorporeal life support - a position paper of the Extracorporeal Life Support Organization

Background

The Extracorporeal Life Support Organization (ELSO) Maastricht Treaty for Nomenclature in Extracorporeal Life Support (ECLS) established consensus nomenclature and abbreviations for ECLS to ensure accurate, concise communication.

Methods

We build on this consensus nomenclature by layering a framework of precise and efficient abbreviations for cannula configuration that describe flow direction, number of cannulae used, any additional ECLS-related catheters, and cannulation sites. This work is a consensus of international representatives of the ELSO, including those from the North American, Latin American, European, South and West Asian, and Asian-Pacific chapters of ELSO.

Results

The classification increases in descriptive capability by introducing a third (cannula tip position) and fourth (cannula dimension) level to those provided in the previous consensus on ECLS cannulation configuration nomenclature. This expansion offers the simplest level needed to convey cannulation information yet allows for more details when required.

Conclusions

A complete nomenclature for ECLS cannulation configurations accommodating future revisions was developed to facilitate ability to compare practices and results, to promote efficient communication, and to improve quality of registry data.

Electronic supplementary material

The online version of this article (10.1186/s13054-019-2334-8) contains supplementary material, which is available to authorized users.

The impact of venovenous extracorporeal membrane oxygenation on cytokine levels in patients with severe acute respiratory distress syndrome: a prospective, observational study

OBJECTIVE

The immunoinflammatory response is central to the pathogenesis of acute respiratory distress syndrome (ARDS). However, little is known how this is affected by venovenous (VV) extracorporeal membrane oxygenation (ECMO). Our objective was to investigate the factors that influence the inflammatory response of patients with ARDS undergoing VV ECMO, and to analyse the impact of this response on hospital mortality.

DESIGN AND SETTING

A prospective observational study of all consecutive patients with severe ARDS who had VV ECMO at a tertiary German ECMO centre from 2009 to 2015. Patients without complete datasets were excluded. Cytokines (interleukin [IL]6, IL8 and tissue necrosis factor [TNF]_α) and inflammatory markers (white cell count and C-reactive protein) were assessed before ECMO initiation and on Days 1, 5 and 10, before explantation and at explantation.

RESULTS

A total of 262 adult patients undergoing VV ECMO were analysed. Their median Sequential Organ Failure Assessment score was 12, PaO₂/FiO₂ ratio was 64 mmHg, and overall in-hospital mortality was 34%. Cytokine levels fell quickly within 24 hours and fell further over the first 5 days. Extra-pulmonary ARDS was associated with higher IL6 and IL8 levels compared with pulmonary ARDS. Mechanical ventilation with positive end-expiratory pressure ≥ 15 cmH₂O before ECMO was associated with higher IL6, IL8 and TNF_α levels. Driving pressures ≥ 19 cmH₂O before ECMO were associated with higher IL8 levels. Non-survivors had higher IL6 and IL8 levels for the duration of ECMO.

CONCLUSION

Cytokine levels, on average, fall rapidly after initiation of VV ECMO, which may be related to the reduction of invasiveness of mechanical ventilation. Higher cytokine levels are associated with extrapulmonary causes of ARDS, more aggressive mechanical ventilation before VV ECMO, and mortality.

Acquired von Willebrand syndrome in respiratory extracorporeal life support: a systematic review of the literature

BACKGROUND AND OBJECTIVE

Venovenous extracorporeal membrane oxygenation (VV ECMO) and extracorporeal CO2 removal (ECCO2R) are increasingly used in the management of severe respiratory failure. With bleeding complications being one of the major risks of these techniques, our aim in this systematic review was to assess the available literature on acquired von Willebrand syndrome (AvWS) and extracorporeal support. AvWS has previously been associated with bleeding and shear stress.

DESIGN AND DATA SOURCES

A systematic review, using Medline via PubMed, was performed to identify eligible studies up to January 2017.

RESULTS AND CONCLUSION

The prevalence of AvWF among patients on VV ECMO or ECCO2R is high, but only a limited number of studies are reported in the literature. AvWS testing should be performed, including vWF multimer analysis, vWF activity and vWF antigen concentration. The extent to which vWF contributes to bleeding during ECMO, or how much changes in ECMO management can influence high molecular weight vWF multimer levels, cannot be answered from the currently available evidence and there remains a need for future studies.

Management strategies in venovenous extracorporeal membrane oxygenation: a retrospective comparison from five European centres

OBJECTIVE

To investigate contemporary clinical practice in the management of venovenous (VV) extracorporeal membrane oxygenation (ECMO) in critically ill patients with bacterial pneumonia.

METHODS

In this multicentre retrospective study, 48 patients with severe respiratory failure due to bacterial pneumonia receiving VV ECMO therapy in five experienced European ECMO centres were included. Ventilator and ECMO settings were analysed.

RESULTS

Ventilator settings showed great variability between participating centres, particularly relating to positive end-expiratory pressure, peak inspiratory pressure and driving pressure. Different strategies in cannulation, ECMO setting and weaning procedures were also observed.

CONCLUSION

There is great diversity in management modalities for ventilator and ECMO settings for patients with bacterial pneumonia. Our study emphasises the lack of clinical consensus in VV ECMO management.

[Bronchopulmonary manifestations of gastroesophageal reflux disease]

Gastroesophageal reflux disease (GERD) is a common disease in the western world. Usually it occurs with typical symptoms like heartburn and regurgitation, but almost every third GERD-patient presents with extraesophageal symptoms and diseases in which a causal relation with GERD is discussed. The extraesophageal symptoms possibly associated with GERD are chronic cough, bronchial asthma, sleep disturbances including obstructive sleep apnea, hoarseness, dental erosions, non-cardiac chest pain and idiopathic pulmonary fibrosis. This article gives an overview of the reflux-associated diseases of the airways as well as the proposed pathomechanisms and therapeutic options.

Gastroesophageal reflux disease and management in advanced pregnancy: a prospective survey

BACKGROUND

Heartburn is known to be common during pregnancy, however validated data on gastroesophageal reflux disease (GERD) are missing. The aim of this survey was to study the prevalence of GERD, the frequency and severity of typical GERD symptoms, and their impact on quality of life and therapeutic management in advanced pregnancy.

METHODS

One hundred and thirty-five consecutive pregnant women in the third trimester were included in a prospective study using validated questionnaires: RDQ, QOLRAD and a self-administered questionnaire detailing sociodemographic factors.

RESULTS

The prevalence for GERD in this unselected population was 56.3%. Among symptoms regurgitation was the most frequent with 47.3%, whereas heartburn was graded as the most severe symptom. The impact of GERD on the QOL of the pregnant women was significant (p < 0.001). 22.9% of the GERD population required medication because of severe symptoms, often reported to be insufficient for symptoms relief.

CONCLUSION

GERD is common in late pregnancy with an important negative impact on the QOL. GERD in advanced pregnancy deserves more attention and better therapeutic management.

The elucidation of peptic esophagitis: from Hamperl to heartburn

Although the esophagus was initially considered as the "humble" organ, it has in recent times evoked both substantial interest and considerable controversy as esophagitis becomes a global pandemic and the debate over the causes of esophagitis and the management of Barrett's has escalated. The esophagus has always defied easy understanding and the origins of its name and its symptomatology continue to confound those who address them. Esophagitis is increasing relentlessly on a global scale and the challenge of defining its symptomatology remains today as great a problem as when initially identified by Herwig Hamperl and Asher Winkelstein. Their identification of the entity they called "peptic esophagitis" in 1934, while initially for the most part overlooked, has today become one of the centers of gastroenterological focus. Although the initial symptomatology of esophagitis was limited to heartburn, it has more recently become apparent that a diverse group of symptoms is produced by the inflammation associated with intermittent reflux of gastric acid. Of interest is the nature of the original observations that led to the identification of the physiopathology of esophagitis and the elucidation of the relationship between symptomatology, acid reflux and inflammation. Although Asher Winkelstein of New York has long been considered the first to define the relationship of acid peptic reflux, esophageal ulceration and reflux symptomatology, it is of note to consider the seminal role of Herwig Hamperl, an Austrian pathologist in the elucidation of acid peptic esophagitis. Indeed, a careful consideration of the relative contributions of these two pioneers suggests that both deserve credit for identifying a disease process that, although initially for the most part ignored by clinicians, has now become one of the most fundamental problems faced by both gastroenterologists and pathologists.