Effects of Neurally Adjusted Ventilatory Assist (NAVA) levels in non-invasive ventilated patients: titrating NAVA levels with electric diaphragmatic activity and tidal volume matching

BACKGROUND: Neurally adjusted ventilatory assist (NAVA) delivers pressure in proportion to diaphragm electrical activity (Eadi). However, each patient responds differently to NAVA levels. This study aims to examine the matching between tidal volume (Vt) and patients' inspiratory demand (Eadi), and to investigate patient-specific response to various NAVA levels in non-invasively ventilated patients. METHODS: 12 patients were ventilated non-invasively with NAVA using three different NAVA levels. NAVA100 was set according to the manufacturer's recommendation to have similar peak airway pressure as during pressure support. NAVA level was then adjusted ±50% (NAVA50, NAVA150). Airway pressure, flow and Eadi were recorded for 15 minutes at each NAVA level. The matching of Vt and integral of Eadi (ʃEadi) were assessed at the different NAVA levels. A metric, Range90, was defined as the 5-95% range of Vt/ʃEadi ratio to assess matching for each NAVA level. Smaller Range90 values indicated better matching of supply to demand. RESULTS: Patients ventilated at NAVA50 had the lowest Range90 with median 25.6 uVs/ml [Interquartile range (IQR): 15.4-70.4], suggesting that, globally, NAVA50 provided better matching between ʃEadi and Vt than NAVA100 and NAVA150. However, on a per-patient basis, 4 patients had the lowest Range90 values in NAVA100, 1 patient at NAVA150 and 7 patients at NAVA50. Robust coefficient of variation for ʃEadi and Vt were not different between NAVA levels. CONCLUSIONS: The patient-specific matching between ʃEadi and Vt was variable, indicating that to obtain the best possible matching, NAVA level setting should be patient specific. The Range90 concept presented to evaluate Vt/ʃEadi is a physiologic metric that could help in individual titration of NAVA level.Peer reviewe

Neurally adjusted ventilatory assist improves patient-ventilator interaction

Purpose: To determine if, compared with pressure support (PS), neurally adjusted ventilatory assist (NAVA) reduces trigger delay, inspiratory time in excess, and the number of patient-ventilator asynchronies in intubated patients. Methods: Prospective interventional study in spontaneously breathing patients intubated for acute respiratory failure. Three consecutive periods of ventilation were applied: (1) PS1, (2) NAVA, (3) PS2. Airway pressure, flow, and transesophageal diaphragmatic electromyography were continuously recorded. Results: All results are reported as median (interquartile range, IQR). Twenty-two patients were included, 36.4% (8/22) having obstructive pulmonary disease. NAVA reduced trigger delay (ms): NAVA, 69 (57-85); PS1, 178 (139-245); PS2, 199 (135-256). NAVA improved expiratory synchrony: inspiratory time in excess (ms): NAVA, 126 (111-136); PS1, 204 (117-345); PS2, 220 (127-366). Total asynchrony events were reduced with NAVA (events/min): NAVA, 1.21 (0.54-3.36); PS1, 3.15 (1.18-6.40); PS2, 3.04 (1.22-5.31). The number of patients with asynchrony index (AI) >10% was reduced by 50% with NAVA. In contrast to PS, no ineffective effort or late cycling was observed with NAVA. There was less premature cycling with NAVA (events/min): NAVA, 0.00 (0.00-0.00); PS1, 0.14 (0.00-0.41); PS2, 0.00 (0.00-0.48). More double triggering was seen with NAVA, 0.78 (0.46-2.42); PS1, 0.00 (0.00-0.04); PS2, 0.00 (0.00-0.00). Conclusions: Compared with standard PS, NAVA can improve patient-ventilator synchrony in intubated spontaneously breathing intensive care patients. Further studies should aim to determine the clinical impact of this improved synchron

Neurally adjusted ventilatory assist (NAVA) improves patient-ventilator interaction during non-invasive ventilation delivered by face mask

Purpose: To determine if, compared to pressure support (PS), neurally adjusted ventilatory assist (NAVA) reduces patient-ventilator asynchrony in intensive care patients undergoing noninvasive ventilation with an oronasal face mask. Methods: In this prospective interventional study we compared patient-ventilator synchrony between PS (with ventilator settings determined by the clinician) and NAVA (with the level set so as to obtain the same maximal airway pressure as in PS). Two 20-min recordings of airway pressure, flow and electrical activity of the diaphragm during PS and NAVA were acquired in a randomized order. Trigger delay (T d), the patient's neural inspiratory time (T in), ventilator pressurization duration (T iv), inspiratory time in excess (T iex), number of asynchrony events per minute and asynchrony index (AI) were determined. Results: The study included 13 patients, six with COPD, and two with mixed pulmonary disease. T d was reduced with NAVA: median 35ms (IQR 31-53ms) versus 181ms (122-208ms); p=0.0002. NAVA reduced both premature and delayed cyclings in the majority of patients, but not the median T iex value. The total number of asynchrony events tended to be reduced with NAVA: 1.0events/min (0.5-3.1events/min) versus 4.4events/min (0.9-12.1events/min); p=0.08. AI was lower with NAVA: 4.9 % (2.5-10.5 %) versus 15.8 % (5.5-49.6 %); p=0.03. During NAVA, there were no ineffective efforts, or late or premature cyclings. PaO2 and PaCO2 were not different between ventilatory modes. Conclusion: Compared to PS, NAVA improved patient ventilator synchrony during noninvasive ventilation by reducing T d and AI. Moreover, with NAVA, ineffective efforts, and late and premature cyclings were absen

Eindrapport Centraal Expertencomité Discriminatie

Recent werden er een aantal initiatieven aangekondigd om discriminatie in kaart te brengen, de monitoring hiervan verder te zetten en/of aangepaste maatregelen te nemen. De minister van Wonen kondigde aan om opnieuw een Woonsurvey door het steunpunt Wonen te organiseren en neemt beleidsinitiatieven met de immosector. De minister van Werk kondigde aan een nulmeting te willen organiseren (en bestelde daartoe een onderzoeksopdracht) en neemt deze problematiek op binnen de sectorconvenants. Ook de minister van Binnenlands beleid en Bestuurszaken kondigde aan een monitoringssysteem te willen ontwikkelen voor de Vlaamse overheid en de lokale besturen. Doordat er verschillende initiatieven worden genomen, wenst de Vlaamse Regering een gemeenschappelijk forum op te richten, waar informatie en expertise over verschillende mogelijke systemen kan worden uitgewisseld. Dit kan tevens de coherentie en afstemming tussen verschillende systemen bevorderen, waarbij op zoek kan gegaan worden naar onderliggende mechanismen of beweegredenen die leiden tot een ongelijke behandeling of uitsluiting. Dit gemeenschappelijk forum werd opgericht in de vorm van een Centraal Expertencomité. Dit Expertencomité werd samengesteld uit academici die een gedegen expertise en gespecialiseerde kennis hebben inzake het wetenschappelijk in kaart brengen, analyseren, monitoren en/of bestrijden van discriminatie of uitsluiting. Het Centraal Expertencomité heeft de opdracht gekregen van de Vlaamse Overheid (VO) om ervaringen en initiatieven over verschillende systemen uit te wisselen en concrete antwoorden te formuleren op de volgende vier vragen: V1) Welke valabele methoden zijn er om discriminatie op te sporen en te monitoren, waarbij rekening wordt gehouden met de specificiteit van de verschillende domeinen (Wonen, Werk, VO als werkgever)? De bedoeling is dat er op een onafhankelijke, effectieve en academische wijze kan gemonitord worden wat de aard en het volume van de discriminatie op geaggregeerd niveau is. V2) Welke methoden kunnen ook als sensibiliserend instrument ingezet worden? V3) Met welke methoden kunnen lokale besturen aan de slag, compatibel aan het Vlaamse instrumentarium voor wonen, arbeidsmarkt en de VO, en wat zijn hier de randvoorwaarden? V4) Welke gerichte onderzoeksvragen kunnen geformuleerd worden ter verdieping van de kennis over de strijd tegen discriminatie (bv. wat zijn onderliggende mechanismen die leiden tot een ongelijke behandeling of uitsluiting)? Op basis van de resultaten van het Centraal Expertencomité zal o.a. een sensibiliserende nulmeting bij de Vlaamse overheid worden toegepast om binnen de respectievelijke diensten een zicht te krijgen op de aard en de grootteorde van discriminatie bij personeelsaangelegenheden (bv. bij aanwerving). In lijn met deze doelstelling, hebben de experten, met uitzondering van Stefan Sottiaux (wat vooraf ook zo was afgesproken), een paper geschreven op basis van hun expertise en onderzoeken tot op vandaag. Een synthese van dit werk vormde de inhoud van een tussentijds rapport dat midden oktober is afgeleverd. Daaropvolgend werden er vanaf de tweede helft van oktober reflectiemomenten georganiseerd met het Expertencomité. Dit om de bespreking en het debat rond de 4 kernvragen te voorzien en concluderende antwoorden te formuleren. Deze terugkoppeling is opgenomen in dit eindrapport. De adviezen in dit eindrapport zijn dus gebaseerd op enerzijds de individuele papers van de experten alsook de onderlinge besprekingen tijdens de reflectiemomenten. Dit eindrapport formuleert antwoorden specifiek binnen de contouren die zijn gevraagd door de opdrachtgever. Binnen deze contouren worden dus geen adviezen gegeven voor de volledige handhavingscyclus – nl. voor monitoren en sensibiliseren wel, maar bestraffen wordt buiten beschouwing gelaten

Identifying associations between diabetes and acute respiratory distress syndrome in patients with acute hypoxemic respiratory failure : an analysis of the LUNG SAFE database

Background: Diabetes mellitus is a common co-existing disease in the critically ill. Diabetes mellitus may reduce the risk of acute respiratory distress syndrome (ARDS), but data from previous studies are conflicting. The objective of this study was to evaluate associations between pre-existing diabetes mellitus and ARDS in critically ill patients with acute hypoxemic respiratory failure (AHRF). Methods: An ancillary analysis of a global, multi-centre prospective observational study (LUNG SAFE) was undertaken. LUNG SAFE evaluated all patients admitted to an intensive care unit (ICU) over a 4-week period, that required mechanical ventilation and met AHRF criteria. Patients who had their AHRF fully explained by cardiac failure were excluded. Important clinical characteristics were included in a stepwise selection approach (forward and backward selection combined with a significance level of 0.05) to identify a set of independent variables associated with having ARDS at any time, developing ARDS (defined as ARDS occurring after day 2 from meeting AHRF criteria) and with hospital mortality. Furthermore, propensity score analysis was undertaken to account for the differences in baseline characteristics between patients with and without diabetes mellitus, and the association between diabetes mellitus and outcomes of interest was assessed on matched samples. Results: Of the 4107 patients with AHRF included in this study, 3022 (73.6%) patients fulfilled ARDS criteria at admission or developed ARDS during their ICU stay. Diabetes mellitus was a pre-existing co-morbidity in 913 patients (22.2% of patients with AHRF). In multivariable analysis, there was no association between diabetes mellitus and having ARDS (OR 0.93 (0.78-1.11); p = 0.39), developing ARDS late (OR 0.79 (0.54-1.15); p = 0.22), or hospital mortality in patients with ARDS (1.15 (0.93-1.42); p = 0.19). In a matched sample of patients, there was no association between diabetes mellitus and outcomes of interest. Conclusions: In a large, global observational study of patients with AHRF, no association was found between diabetes mellitus and having ARDS, developing ARDS, or outcomes from ARDS. Trial registration: NCT02010073. Registered on 12 December 2013

Death in hospital following ICU discharge : insights from the LUNG SAFE study

Background: To determine the frequency of, and factors associated with, death in hospital following ICU discharge to the ward. Methods: The Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE study was an international, multicenter, prospective cohort study of patients with severe respiratory failure, conducted across 459 ICUs from 50 countries globally. This study aimed to understand the frequency and factors associated with death in hospital in patients who survived their ICU stay. We examined outcomes in the subpopulation discharged with no limitations of life sustaining treatments (‘treatment limitations’), and the subpopulations with treatment limitations. Results: 2186 (94%) patients with no treatment limitations discharged from ICU survived, while 142 (6%) died in hospital. 118 (61%) of patients with treatment limitations survived while 77 (39%) patients died in hospital. Patients without treatment limitations that died in hospital after ICU discharge were older, more likely to have COPD, immunocompromise or chronic renal failure, less likely to have trauma as a risk factor for ARDS. Patients that died post ICU discharge were less likely to receive neuromuscular blockade, or to receive any adjunctive measure, and had a higher pre- ICU discharge non-pulmonary SOFA score. A similar pattern was seen in patients with treatment limitations that died in hospital following ICU discharge. Conclusions: A significant proportion of patients die in hospital following discharge from ICU, with higher mortality in patients with limitations of life-sustaining treatments in place. Non-survivors had higher systemic illness severity scores at ICU discharge than survivors. Trial Registration: ClinicalTrials.gov NCT02010073

Epidemiology and patterns of tracheostomy practice in patients with acute respiratory distress syndrome in ICUs across 50 countries

Background: To better understand the epidemiology and patterns of tracheostomy practice for patients with acute respiratory distress syndrome (ARDS), we investigated the current usage of tracheostomy in patients with ARDS recruited into the Large Observational Study to Understand the Global Impact of Severe Acute Respiratory Failure (LUNG-SAFE) study. Methods: This is a secondary analysis of LUNG-SAFE, an international, multicenter, prospective cohort study of patients receiving invasive or noninvasive ventilation in 50 countries spanning 5 continents. The study was carried out over 4 weeks consecutively in the winter of 2014, and 459 ICUs participated. We evaluated the clinical characteristics, management and outcomes of patients that received tracheostomy, in the cohort of patients that developed ARDS on day 1-2 of acute hypoxemic respiratory failure, and in a subsequent propensity-matched cohort. Results: Of the 2377 patients with ARDS that fulfilled the inclusion criteria, 309 (13.0%) underwent tracheostomy during their ICU stay. Patients from high-income European countries (n = 198/1263) more frequently underwent tracheostomy compared to patients from non-European high-income countries (n = 63/649) or patients from middle-income countries (n = 48/465). Only 86/309 (27.8%) underwent tracheostomy on or before day 7, while the median timing of tracheostomy was 14 (Q1-Q3, 7-21) days after onset of ARDS. In the subsample matched by propensity score, ICU and hospital stay were longer in patients with tracheostomy. While patients with tracheostomy had the highest survival probability, there was no difference in 60-day or 90-day mortality in either the patient subgroup that survived for at least 5 days in ICU, or in the propensity-matched subsample. Conclusions: Most patients that receive tracheostomy do so after the first week of critical illness. Tracheostomy may prolong patient survival but does not reduce 60-day or 90-day mortality

Corticosteroid therapy is associated with a decrease in mortality in a multicenter cohort of mechanically ventilated COVID-19 patients

peer reviewedRetrospectively analyzing the data of a multicenter cohort, we observed that mortality of patients with SARS-CoV-2 pneumoniatreated with mechanical ventilation was as high as 45% and median survival time was 82 days. In this series, the risk factors for mortality included age, renal and circulatory dysfunction, lymphopenia and the absence of corticosteroid use during the first week of mechanical ventilation. Corticosteroid therapy during the first week of mechanical ventilation was associated with a lower mortality (34% vs 48%) (p = 0,01)