Blood endothelium transition and phenotypic plasticity: A key regulator of integrity/permeability in response to ischemia.

In the human body, the 1013 blood endothelial cells (ECs) which cover a surface of 500-700 m2 (Mai et al., 2013) are key players of tissue homeostasis, remodeling and regeneration. Blood vessel ECs play a major role in the regulation of metabolic and gaz exchanges, cell trafficking, blood coagulation, vascular tone, blood flow and fluid extravasation (also referred to as blood vascular permeability). ECs are heterogeneous in various capillary beds and have the exquisite capacity to cope with environmental changes by regulating their gene expression. Ischemia has major detrimental effects on the endothelium and ischemia-induced regulation of vascular integrity is of paramount importance for human health, as small amounts of fluid accumulation in the interstitium may be responsible for major effects on organ functions and patients outcome. In this review, we will here focus on the stimuli and the molecular mechanisms that control blood endothelium maintenance and phenotypic plasticity/transition involved in controlling blood capillary leakage that might open new avenues for therapeutic applications.

FX06 to rescue SARS-CoV-2-induced acute respiratory distress syndrome: a randomized clinical trial.

BACKGROUND: Vascular leakage is a major feature of acute respiratory distress syndrome (ARDS). We aimed to evaluate the efficacy of FX06, a drug under development that stabilizes interendothelial cell junctions, at reducing vascular leakage during SARS-CoV-2-induced ARDS. METHODS: This multicenter, double-blinded, randomized trial included adults with COVID-19-associated ARDS who had received invasive mechanical ventilation for < 5 days and were randomized to receive either intravenous FX06 (400 mg/d, for 5 days) or its vehicle as placebo. The primary endpoint was the lowering-from day 1 to day 7-of the transpulmonary thermodilution-derived extravascular lung-water index (EVLWi). RESULTS: Twenty-five patients were randomized to receive FX06 and 24 the placebo. Although EVLWi was elevated at baseline (median [IQR] 15.6 mL/kg [13.5; 18.5]), its declines from day 1 to day 7 were comparable for FX06 recipients and controls (respectively, - 1.9 [- 3.3; - 0.5] vs. - 0.8 [- 5.5; - 1.1] mL/kg; estimated effect - 0.8 [- 3.1; + 2.4], p = 0.51). Cardiac indexes, pulmonary vascular permeability indexes, and fluid balances were also comparable, as were PaO2/FiO2 ratios and durations of mechanical ventilation. Adverse event rates were similar for the 2 groups, although more FX06 recipients developed ventilator-associated pneumonia (16/25 (64%) vs. 6/24 (24%), p = 0.009). CONCLUSIONS: In this unique-dosing-regimen study, FX06 did not lower SARS-CoV-2-induced pulmonary vascular leakage. Future investigations will need to evaluate its efficacy at earlier times during the disease or using other regimens. Trial registration NCT04618042. Registered 5 November 2020.

Prone-Positioning for Severe Acute Respiratory Distress Syndrome Requiring Extracorporeal Membrane Oxygenation.

OBJECTIVES: To determine the characteristics and outcomes of patients prone-positioned during extracorporeal membrane oxygenation for severe acute respiratory distress syndrome and lung CT pattern associated with improved respiratory system static compliance after that intervention. DESIGN: Retrospective, single-center study over 8 years. SETTINGS: Twenty-six bed ICU in a tertiary center. MEASUREMENTS AND MAIN RESULTS: A propensity score-matched analysis compared patients with prone-positioning during extracorporeal membrane oxygenation and those without. An increase of the static compliance greater than or equal to 3 mL/cm H2O after 16 hours of prone-positioning defined prone-positioning responders. The primary outcome was the time to successful extracorporeal membrane oxygenation weaning within 90 days of postextracorporeal membrane oxygenation start, with death as a competing risk. Among 298 venovenous extracorporeal membrane oxygenation-treated adults with severe acute respiratory distress syndrome, 64 were prone-positioning extracorporeal membrane oxygenation. Although both propensity score-matched groups had similar extracorporeal membrane oxygenation durations, prone-positioning extracorporeal membrane oxygenation patients' 90-day probability of being weaned-off extracorporeal membrane oxygenation and alive was higher (0.75 vs 0.54, p = 0.03; subdistribution hazard ratio [95% CI], 1.54 [1.05-2.58]) and 90-day mortality was lower (20% vs 42%, p < 0.01) than that for no prone-positioning extracorporeal membrane oxygenation patients. Extracorporeal membrane oxygenation-related complications were comparable for the two groups. Patients without improved static compliance had higher percentages of nonaerated or poorly aerated ventral and medial-ventral lung regions (p = 0.047). CONCLUSIONS: Prone-positioning during venovenous extracorporeal membrane oxygenation was safe and effective and was associated with a higher probability of surviving and being weaned-off extracorporeal membrane oxygenation at 90 days. Patients with greater normally aerated lung tissue in the ventral and medial-ventral regions on quantitative lung CT-scan performed before prone-positioning are more likely to improve their static compliance after that procedure during extracorporeal membrane oxygenation.

Electrical Impedance Tomography Monitoring of Bronchoalveolar Lavage in Patients With Acute Respiratory Distress Syndrome.

OBJECTIVES: The impact of bronchoalveolar lavage on regional ventilation in mechanically ventilated patients with acute respiratory distress syndrome has rarely been described. Our objectives were use electrical impedance tomography to describe lung impedance variation post bronchoalveolar lavage and identify morphologic patterns according to respiratory failure severity. DESIGN: Monocenter physiologic study on mechanically ventilated patients. SETTING: University medical ICU. INTERVENTIONS: After a recruitment maneuver, tidal impedance variation distributions (a surrogate for impact of bronchoalveolar lavage on tidal volume distribution), end-expiratory lung impedance (correlated with end-expiratory lung volume and used to quantify postbronchoalveolar lavage derecruitment), respiratory mechanics, and blood gases were recorded before and over 6 hours post bronchoalveolar lavage with Pao2 to the Fio2 ratio. Patients were grouped according to their prebronchoalveolar lavage, that is, Pao2 to the Fio2 ratio less than 200 or greater than or equal to 200. RESULTS: Twenty-one patients (median [interquartile range] age 55 yr [50-58 yr]; 13 males), 13 with Pao2 to the Fio2 ratio less than 200, were included. Unlike that latter group, bronchoalveolar lavage significantly impacted tidal impedance variation distribution in patients with Pao2 to the Fio2 ratio greater than or equal to 200, with a ventilation shift to the contralateral lung (from 54% to 42% in the bronchoalveolar lavage side), which persisted up to 6 hours post bronchoalveolar lavage. Similarly, end-expiratory lung impedance was less distributed in the bronchoalveolar lavage side post procedure of patients with Pao2 to the Fio2 ratio greater than or equal to 200, but the difference did not reach statistical significance (p = 0.09). As reported for tidal impedance variation, end-expiratory lung impedance distribution in patients with severe or moderate acute respiratory distress syndrome did not change significantly during the 6 hours post bronchoalveolar lavage. Although bronchoalveolar lavage effects on gas exchanges were minor in all patients, static compliance in patients with Pao2 to the Fio2 ratio greater than or equal to 200 was significantly lower post bronchoalveolar lavage (p = 0.04). CONCLUSIONS: The negative impact of bronchoalveolar lavage on regional ventilation, which persisted at least 6 hours, appeared to be more profound in patients with normal lung function or mild acute respiratory distress syndrome. In contrast, regional ventilation, lung recruitment, respiratory mechanics, and gas exchanges were modestly impacted by the bronchoalveolar lavage in patients with severe or moderate acute respiratory distress syndrome. That finding is reassuring and supports not summarily proscribing bronchoalveolar lavage for the most severely ill with acute respiratory distress syndrome.

Amniotic fluid embolism rescued by venoarterial extracorporeal membrane oxygenation.

BACKGROUND: Amniotic fluid embolism (AFE) is a rare but often catastrophic complication of pregnancy that leads to cardiopulmonary dysfunction and severe disseminated intravascular coagulopathy (DIC). Although few case reports have reported successful use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) with AFE, concerns can be raised about the increased bleeding risks with that device. METHODS: This study included patients with AFE rescued by VA-ECMO hospitalized in two high ECMO volume centers between August 2008 and February 2021. Clinical characteristics, critical care management, in-intensive care unit (ICU) complications, and hospital outcomes were collected. ICU survivors were assessed for health-related quality of life (HRQL) in May 2021. RESULTS: During that 13-year study period, VA-ECMO was initiated in 54 parturient women in two high ECMO volume centers. Among that population, 10 patients with AFE [median (range) age 33 (24-40), SAPS II at 69 (56-81)] who fulfilled our diagnosis criteria were treated with VA-ECMO. Pregnancy evolved for 36 (30-41) weeks. Seven patients had a cardiac arrest before ECMO and two were cannulated under cardiopulmonary resuscitation. Pre-ECMO hemodynamic was severely impaired with an inotrope score at 370 (55-1530) µg/kg/min, a severe left ventricular ejection fraction measured at 14 (0-40)%, and lactate at 12 (2-30) mmol/L. 70% of these patients were alive at hospital discharge despite an extreme pre-ECMO severity and massive blood product transfusion. However, HRQL was lower than age-matched controls and still profoundly impaired in the role-physical, bodily pain, and general health components after a median of 44 months follow-up. CONCLUSION: In this rare per-delivery complication, our results support the use of VA-ECMO despite intense DIC and ongoing bleeding. Future studies should focus on customized, patient-centered, rehabilitation programs that could lead to improved HRQL in this population.

Delivery decision in pregnant women rescued by ECMO for severe ARDS: a retrospective multicenter cohort study.

BACKGROUND: Although rarely addressed in the literature, a key question in the care of critically pregnant women with severe acute respiratory distress syndrome (ARDS), especially at the time of extracorporeal membrane oxygenation (ECMO) decision, is whether delivery might substantially improve the mother's and child's conditions. This multicenter, retrospective cohort aims to report maternal and fetal short- and long-term outcomes of pregnant women with ECMO-rescued severe ARDS according to the timing of the delivery decision taken before or after ECMO cannulation. METHODS: We included critically ill women with ongoing pregnancy or within 15 days after a maternal/child-rescue-aimed delivery supported by ECMO for a severe ARDS between October 2009 and August 2021 in four ECMO centers. Clinical characteristics, critical care management, complications, and hospital discharge status for both mothers and children were collected. Long-term outcomes and premature birth complications were assessed. RESULTS: Among 563 women on venovenous ECMO during the study period, 11 were cannulated during an ongoing pregnancy at a median (range) of 25 (21-29) gestational weeks, and 13 after an emergency delivery performed at 32 (17-39) weeks of gestation. Pre-ECMO PaO2/FiO2 ratio was 57 (26-98) and did not differ between the two groups. Patients on ECMO after delivery reported more major bleeding (46 vs. 18%, p = 0.05) than those with ongoing pregnancy. Overall, the maternal hospital survival was 88%, which was not different between the two groups. Four (36%) of pregnant women had a spontaneous expulsion on ECMO, and fetal survival was higher when ECMO was set after delivery (92% vs. 55%, p = 0.03). Among newborns alive, no severe preterm morbidity or long-term sequelae were reported. CONCLUSION: Continuation of the pregnancy on ECMO support carries a significant risk of fetal death while improving prematurity-related morbidity in alive newborns with no difference in maternal outcomes. Decisions regarding timing, place, and mode of delivery should be taken and regularly (re)assess by a multidisciplinary team in experienced ECMO centers.

Viral Ventilator-Associated Pneumonia/Hospital-Acquired Pneumonia.

Among the viruses possibly responsible for hospital-acquired and ventilator-associated pneumonia, herpes simplex virus (HSV) is probably the most often involved: HSV reactivation is frequent in intensive care unit patients, and lung parenchymal infection (HSV bronchopneumonitis) has been well described, either using cytological signs of parenchymal involvement in cells obtained during bronchoalveolar lavage or using HSV virus load in the lower respiratory tract. Although treating patients with HSV bronchopneumonitis may be recommended, based on expert opinion, prophylactic or preemptive treatment of HSV reactivation should be avoided. Ventilator-associated pneumonia due to cytomegalovirus (CMV) is less frequent than HSV bronchopneumonitis, and more difficult to diagnose. No data exists on the impact of antiviral treatment on CMV pneumonia. The involvement of respiratory viruses has been described in patients with healthcare-associated pneumonia and hospital-acquired pneumonia, but their role in ventilator-associated pneumonia is not clear.

Venoarterial extracorporeal membrane oxygenation to rescue sepsis-induced cardiogenic shock: a retrospective, multicentre, international cohort study.

BACKGROUND: Patients with sepsis-induced cardiomyopathy with cardiogenic shock have a high mortality. This study assessed venoarterial extracorporeal membrane oxygenation (VA-ECMO) support for sepsis-induced cardiogenic shock refractory to conventional treatments. METHODS: In this retrospective, multicentre, international cohort study, we compared outcomes of 82 patients (aged ≥18 years) with septic shock who received VA-ECMO at five academic ECMO centres, with 130 controls (not receiving ECMO) obtained from three large databases of septic shock. All patients had severe myocardial dysfunction (cardiac index 3 L/min per m2 or less or left ventricular ejection fraction [LVEF] 35% or less) and severe haemodynamic compromise (inotrope score at least 75 µg/kg per min or lactic acidaemia at least 4 mmol/L) at time of inclusion. The primary endpoint was survival at 90 days. A propensity score-weighted analysis was done to control for confounders. FINDINGS: At baseline, patients treated with VA-ECMO had more severe myocardial dysfunction (mean cardiac index 1·5 L/min per m2vs 2·2 L/min per m2, LVEF 17% vs 27%), more severe haemodynamic impairment (inotrope score 279 µg/kg per min vs 145 µg/kg per min, lactataemia 8·9 mmol/L vs 6·5 mmol/L), and more severe organ failure (Sequential Organ Failure Assessment score 17 vs 13) than did controls, with p<0·0001 for each comparison. Survival at 90 days for patients treated with VA-ECMO was significantly higher than for controls (60% vs 25%, risk ratio [RR] for mortality 0·54, 95% CI [0·40-0·70]; p<0·0001). After propensity score weighting, ECMO remained associated with improved survival (51% vs 14%, adjusted RR for mortality 0·57, 95% CI [0·35-0·93]; p=0·0029). Lactate and catecholamine clearance were also significantly enhanced in patients treated with ECMO. Among the 49 survivors treated with ECMO, 32 who had been treated at the largest centre reported satisfactory Short Form-36 evaluated health-related quality of life at 1-year follow-up. INTERPRETATION: Patients with severe sepsis-induced cardiogenic shock treated with VA-ECMO had a large and significant improvement in survival compared with controls not receiving ECMO. However, despite the careful propensity-weighted analysis, we cannot rule out unmeasured confounders. FUNDING: None.

Association between cytomegalovirus infection and allograft rejection in a large contemporary cohort of heart transplant recipients.

BACKGROUND: Cytomegalovirus (CMV) infection remains a common complication after heart transplantation (HTx). The association between CMV infection and allograft rejection is debated in the era of efficient prophylactic antiviral therapies. METHODS: This single-center cohort study utilized a highly phenotyped database of HTx recipients (2012-2016). The primary endpoint was the analysis of the association between CMV infection (CMV load ≥ 500 IU/mL whole blood) and the risk of allograft rejection (cellular rejection ≥ 1R1B, antibody-mediated rejection ≥ pAMR1). Secondary endpoints included the analysis of a higher CMV load threshold (≥10 000 IU/mL) and different risk periods after PCR positivity. A mixed-effect logistic regression model with a random intercept was applied. Results were adjusted for important risk factors of rejection. RESULTS: Overall, 384 patients were included and 6388 CMV loads and 3,494 endomyocardial biopsies were analyzed. CMV infections ≥ 500 IU/mL were diagnosed on 1223 (19.2%) blood samples from 284 (72.1%) patients and allograft rejections on 246 biopsies (7%) from 149 patients (38.8%). We did not find any association between CMV infection ≥ 500 IU/mL and rejection (univariable: OR 0.94, 95% CI [0.61, 1.45], P = .78, multivariable: OR 0.86, 95% CI [0.55, 1.33], P = .85). These results were consistent when analyzing a higher CMV load threshold and different periods of risk, reinforced by internal validation procedures and a posteriori calculation of the power (primary endpoint: power = 0.82, 95% CI [0.79-0.84]) and reproducible across different clinical scenarios. CONCLUSIONS: CMV infection was not associated with an increased risk of rejection in a contemporary cohort of HTx recipients.

Venoarterial extracorporeal membrane oxygenation as mechanical circulatory support in adult septic shock: a systematic review and meta-analysis with individual participant data meta-regression analysis.

BACKGROUND: While recommended by international societal guidelines in the paediatric population, the use of venoarterial extracorporeal membrane oxygenation (VA ECMO) as mechanical circulatory support for refractory septic shock in adults is controversial. We aimed to characterise the outcomes of adults with septic shock requiring VA ECMO, and identify factors associated with survival. METHODS: We searched Pubmed, Embase, Scopus and Cochrane databases from inception until 1st June 2021, and included all relevant publications reporting on > 5 adult patients requiring VA ECMO for septic shock. Study quality and certainty in evidence were assessed using the appropriate Joanna Briggs Institute checklist, and the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach, respectively. The primary outcome was survival to hospital discharge, and secondary outcomes included intensive care unit length of stay, duration of ECMO support, complications while on ECMO, and sources of sepsis. Random-effects meta-analysis (DerSimonian and Laird) were conducted. DATA SYNTHESIS: We included 14 observational studies with 468 patients in the meta-analysis. Pooled survival was 36.4% (95% confidence interval [CI]: 23.6%-50.1%). Survival among patients with left ventricular ejection fraction (LVEF) < 20% (62.0%, 95%-CI: 51.6%-72.0%) was significantly higher than those with LVEF > 35% (32.1%, 95%-CI: 8.69%-60.7%, p = 0.05). Survival reported in studies from Asia (19.5%, 95%-CI: 13.0%-26.8%) was notably lower than those from Europe (61.0%, 95%-CI: 48.4%-73.0%) and North America (45.5%, 95%-CI: 16.7%-75.8%). GRADE assessment indicated high certainty of evidence for pooled survival. CONCLUSIONS: When treated with VA ECMO, the majority of patients with septic shock and severe sepsis-induced myocardial depression survive. However, VA ECMO has poor outcomes in adults with septic shock without severe left ventricular depression. VA ECMO may be a viable treatment option in carefully selected adult patients with refractory septic shock.

Evolving outcomes of extracorporeal membrane oxygenation support for severe COVID-19 ARDS in Sorbonne hospitals, Paris.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) was frequently used to treat patients with severe coronavirus disease-2019 (COVID-19)-associated acute respiratory distress (ARDS) during the initial outbreak. Care of COVID-19 patients evolved markedly during the second part of 2020. Our objective was to compare the characteristics and outcomes of patients who received ECMO for severe COVID-19 ARDS before or after July 1, 2020. METHODS: We included consecutive adults diagnosed with COVID-19 in Paris-Sorbonne University Hospital Network ICUs, who received ECMO for severe ARDS until January 28, 2021. Characteristics and survival probabilities over time were estimated during the first and second waves. Pre-ECMO risk factors predicting 90-day mortality were assessed using multivariate Cox regression. RESULTS: Characteristics of the 88 and 71 patients admitted, respectively, before and after July 1, 2020, were comparable except for older age, more frequent use of dexamethasone (18% vs. 82%), high-flow nasal oxygenation (19% vs. 82%) and/or non-invasive ventilation (7% vs. 37%) after July 1. Respective estimated probabilities (95% confidence intervals) of 90-day mortality were 36% (27-47%) and 48% (37-60%) during the first and the second periods. After adjusting for confounders, probability of 90-day mortality was significantly higher for patients treated after July 1 (HR 2.27, 95% CI 1.02-5.07). ECMO-related complications did not differ between study periods. CONCLUSIONS: 90-day mortality of ECMO-supported COVID-19-ARDS patients increased significantly after July 1, 2020, and was no longer comparable to that of non-COVID ECMO-treated patients. Failure of prolonged non-invasive oxygenation strategies before intubation and increased lung damage may partly explain this outcome.

Incidence and Outcome of Subclinical Acute Kidney Injury Using penKid in Critically Ill Patients.

Rationale: Subclinical acute kidney injury (sub-AKI) refers to patients with low serum creatinine but elevated alternative biomarkers of AKI. Its incidence and outcome in critically ill patients remain, however, largely unknown. Plasma proenkephalin A 119-159 (penKid) has been proposed as a sensitive biomarker of glomerular function.Objectives: In this ancillary study of two cohorts, we explored the incidence and outcome of sub-AKI based on penKid.Methods: A prospective observational study in ICUs was conducted. FROG-ICU (French and European Outcome Registry in ICUs) enrolled 2,087 critically ill patients, and AdrenOSS-1 (Adrenomedullin and Outcome in Severe Sepsis and Septic Shock-1) enrolled 583 septic patients. The primary endpoint was 28-day mortality after ICU admission. Sub-AKI was defined by an admission penKid concentration above the normal range (i.e., >80 pmol/L) in patients not meeting the definition of AKI. A sensitivity analysis was performed among patients with estimated glomerular filtration rate above 60 ml/min/1.73 m2 at ICU admission.Measurements and Main Results: In total, 6.1% (122/2,004) and 6.7% (39/583) of patients from the FROG-ICU and AdrenOSS-1 cohorts met the definition of sub-AKI (11.6% and 17.5% of patients without AKI). In patients without AKI or with high estimated glomerular filtration rate, penKid was associated with higher mortality (adjusted standardized hazard ratio [HR], 1.4 [95% confidence interval, 1.1-1.8]; P = 0.010; and HR, 1.6 [95% confidence interval, 1.3-1.8]; P < 0.0001, respectively) after adjustment for age, sex, comorbidities, diagnosis, creatinine, diuresis, and study. Patients with sub-AKI had higher mortality compared with no AKI (HR, 2.4 [95% confidence interval, 1.5-3.7] in FROG-ICU and 2.5 [95% confidence interval, 1.1-5.9] in AdrenOSS-1).Conclusions: Sub-AKI defined using penKid occurred in 11.6-17.5% of patients without AKI and was associated with a risk of death close to patients with AKI.

Favorable Outcomes of a Direct Heart Transplantation Strategy in Selected Patients on Extracorporeal Membrane Oxygenation Support.

OBJECTIVES: Heart transplantation in patients supported by venoarterial extracorporeal membrane oxygenation has been associated with poor prognosis. A specific protocol for extracorporeal membrane oxygenation management encompassing patient selection, implantation strategy, and preoperative and perioperative treatment is applied at our institution. Our aim was to compare posttransplant outcomes of patients supported or not by extracorporeal membrane oxygenation at the time of heart transplantation. DESIGN: A large observational single-center retrospective study was conducted. The primary endpoint was overall survival after heart transplantation. Secondary endpoints included death-censored rejection-free survival and the frequency of extracorporeal membrane oxygenation-related complications. SETTING: One heart transplantation and extracorporeal membrane oxygenation high-volume center. PATIENTS: All consecutive patients over 18 years old with a first noncombined heart transplantation performed between 2012 and 2016 were included. INTERVENTIONS: None (retrospective observational study). MEASUREMENTS AND MAIN RESULTS: Among the 415 transplanted patients, 118 (28.4%) were on extracorporeal membrane oxygenation at the time of transplantation (peripheral, 94%; intrathoracic, 6%). Median time on extracorporeal membrane oxygenation before heart transplantation was 9 days (interquartile range, 5-15 d) and median follow-up post heart transplantation was 20.7 months. Posttransplant survival did not differ significantly between the two groups (1-yr survival = 85.5% and 80.7% in extracorporeal membrane oxygenation vs nonextracorporeal membrane oxygenation patients; hazard ratio, 0.69; 95% CI, 0.43-1.11; p = 0.12, respectively). Donor age, body mass index, creatinine clearance, and ischemic time were independently associated with overall mortality, but not extracorporeal membrane oxygenation at the time of heart transplantation. Rejection-free survival also did not significantly differ between groups (hazard ratio, 0.85; 95% CI, 0.60-1.23; p = 0.39). Local wound infection was the most frequent complication after extracorporeal membrane oxygenation (37% of patients). CONCLUSIONS: With the implementation of a specific protocol, patients bridged to heart transplantation on extracorporeal membrane oxygenation had similar survival compared with those not supported by extracorporeal membrane oxygenation.

Microcirculation Evolution in Patients on Venoarterial Extracorporeal Membrane Oxygenation for Refractory Cardiogenic Shock.

OBJECTIVES: Despite the increasing use of venoarterial extracorporeal membrane oxygenation to treat severe cardiogenic shock patients, microcirculation data in this context are scarce. We evaluated the venoarterial extracorporeal membrane oxygenation impact on macrocirculatory hemodynamics and microcirculation in patients with refractory cardiogenic shock and compared the evolutions of those parameters between patients successfully weaned-off extracorporeal membrane oxygenation and those who died on extracorporeal membrane oxygenation. DESIGN: Prospective study. SETTING: Academic medical ICU. PATIENTS: Consecutive patients with refractory cardiogenic shock (cardiac arrest excluded) who required venoarterial extracorporeal membrane oxygenation and for whom sublingual microcirculation measurements before cannulation were possible. INTERVENTIONS: All patients were followed until death or venoarterial extracorporeal membrane oxygenation removal. Microcirculatory and macrocirculatory evaluations were made before, and 2, 4, 12, 24, and 48 hours after extracorporeal membrane oxygenation initiation, respectively. Patients weaned-off extracorporeal membrane oxygenation were also evaluated 6 hours before and after venoarterial extracorporeal membrane oxygenation removal. MEASUREMENTS AND MAIN RESULTS: Fourteen patients (median age, 58 yr [interquartile range, 56-62 yr]; Sequential Organ Failure Assessment score, 14 [12-18]) were included. Acute myocardial infarction (50%) was the main cause of cardiogenic shock. Six patients (33%) were successfully weaned-off extracorporeal membrane oxygenation. Profound microcirculation parameter changes found before venoarterial extracorporeal membrane oxygenation implantation regressed within 12 hours after extracorporeal membrane oxygenation onset. Pre-extracorporeal membrane oxygenation macrocirculation, echocardiography, arterial blood gases, and microcirculation parameters did not differ between patients who died on extracorporeal membrane oxygenation and those successfully weaned. However, perfused small-vessel density, small-vessel density, and percent perfused vessels were consistently higher and then stabilized 48 hours postcannulation for patients successfully weaned-off extracorporeal membrane oxygenation. CONCLUSIONS: Microcirculation is severely impaired in patients with refractory cardiogenic shock requiring venoarterial extracorporeal membrane oxygenation. Inability to rapidly restore microcirculation during the first 24 hours, despite normal global/macrocirculatory hemodynamics, was associated with death on extracorporeal membrane oxygenation. Further studies are now warranted to better determine the relevant microcirculation determinants during venoarterial extracorporeal membrane oxygenation support, before future routine use of this promising tool in clinical practice.

Extracorporeal Membrane Oxygenation to Support Life-Threatening Drug-Refractory Electrical Storm.

OBJECTIVES: Despite rapid implementation of anti-arrhythmic treatment and sedation and controlling the triggering event, rare patients develop treatment-refractory electrical storm and their hemodynamic instability prevents emergency catheter ablation. In that context, venoarterial extracorporeal membrane oxygenation could rapidly restore hemodynamics and tissue perfusion and reduce myocardial oxygen consumption, until adequate anti-arrhythmic drug levels are reached to safely perform catheter ablation. DESIGN: Retrospective, multicenter study over an 8-year period. SETTING: Two French tertiary care centers. PATIENTS: Eighty-three consecutive adults with venoarterial extracorporeal membrane oxygenation-supported treatment-refractory electrical storm (median [interquartile range] age, 55 yr [48-63 yr]). MEASUREMENTS AND MAIN RESULTS: Fifty-nine percent of these patients had acute ischemic cardiomyopathy and 66% underwent cardiopulmonary resuscitation prior to venoarterial extracorporeal membrane oxygenation initiation, with 18% cannulated during it. Fifty patients (60%) had ventricular tachycardia and/or ventricular fibrillation alternating with short periods of sinus rhythm and 33 (40%) had refractory ventricular tachycardia and/or ventricular fibrillation. Twelve patients (15%) underwent safe catheter ablation under venoarterial extracorporeal membrane oxygenation. After a median of 3 days (1-13 d) on extracorporeal membrane oxygenation support, 37 patients (45%) were successfully weaned off and 42% were alive 6 months post-ICU admission. Multivariable analysis retained ventricular tachycardia and/or ventricular fibrillation episodes alternating with short periods of sinus rhythm (odds ratio, 0.18; 95% CI, 0.06-0.52; p = 0.002) and age less than 50 years (odds ratio, 0.32; 95% CI, 0.18-0.89; p = 0.002) as being independent protective factors with 6-month survival, regardless of the underlying electrical storm cause. CONCLUSIONS: Among venoarterial extracorporeal membrane oxygenation-supported drug-refractory electrical storm patients, 42% survived 6 months post-ICU admission. Ventricular tachycardia and/or ventricular fibrillation episodes alternating with short periods of sinus rhythm and age less than 50 years were independently associated with better survival.

The place of extracorporeal life support in cardiogenic shock.

PURPOSE OF REVIEW: Temporary circulatory support (TCS) devices are increasingly used as a salvage therapy for patients with refractory cardiogenic shock. The exact place of the different TCS devices in the management of cardiogenic shock patients remains unclear and intensely debated. This article provides an overview on new cardiogenic shock classification, currently available devices, place of TCS in the management of cardiogenic shock patients, and discusses the results of recent case series and trials in this setting. RECENT FINDING: A new classification system for cardiogenic shock has recently been proposed to homogenize definitions of cardiogenic shock and appropriately differentiate patient subsets in clinical trials and registries. Although the routine use of intraaortic balloon pump is no more recommended, other TCS are increasingly used and investigated but many advantages favor the use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) as the first-line TCS. SUMMARY: TCS devices have become the cornerstone of the management of patients with refractory cardiogenic shock. VA-ECMO has emerged as the first-line support system in this setting, with a growing number of accepted indications. Large adequately powered randomized controlled trials are now underway and should help to determine the respective place of different TCS devices in strategies to treat cardiogenic shock patients.

Usefulness of point-of-care multiplex PCR to rapidly identify pathogens responsible for ventilator-associated pneumonia and their resistance to antibiotics: an observational study.

BACKGROUND: The use of multiplex PCR to shorten time to identification of pathogens and their resistance mechanisms for patients with ventilator-associated pneumonia (VAP) is attractive, but poorly studied. The multiplex PCR-based Unyvero pneumonia cartridge assay can directly identify 20 bacteria and one fungus, amongst the most frequently causing VAP, and 19 of their resistance markers in clinical specimens (bronchoalveolar lavage or tracheal aspirate), with a turnaround time of 4-5 h. We performed this study to evaluate the concordance between the multiplex PCR-based Unyvero pneumonia cartridge assay and conventional microbiological techniques to identify pathogens and their resistance mechanisms in patients with VAP. METHODS: All patients suspected of having VAP (January 2016 to January 2019), who underwent fiberoptic bronchoscopy with bronchoalveolar lavage fluid (BALF) and whose BALF microscopy examination revealed intracellular bacteria, were included. BALF conventional cultures (gold standard), antimicrobial susceptibility testing and processing for the Unyvero pneumonia cartridge were done. Culture and Unyvero results were compared. RESULTS: Compared to cultures of the 93 samples processed for both techniques, Unyvero correctly identified pathogens in 68 (73%) proven VAP episodes, was discordant for 25 (27%), detected no pathogen in 11 and overdetected a not otherwise found pathogen in six. For the eight remaining discordant results, the pathogen responsible for VAP was not included in the Unyvero cartridge panel or it grew at a non-significant level in culture. Amongst the 31 (33%) resistance mechanism discordances observed, 22 were resistance detection failures and 24 concerned Pseudomonas aeruginosa. CONCLUSIONS: Compared to conventional microbiological cultures, the Unyvero pneumonia cartridge had poor diagnostic performance: it correctly identified pathogens and their resistance mechanisms in 73% and 67% of VAP cases, respectively. The lack of performance on the resistance mechanism was more pronounced when the pathogen detected was a Pseudomonas aeruginosa.

Severe diffuse alveolar hemorrhage related to autoimmune disease: a multicenter study.

BACKGROUND: Diffuse alveolar hemorrhage (DAH) occurs during the course of autoimmune disease and may be life threatening. The objective was to assess characteristics and prognosis factors of DAH who required intensive care unit (ICU) admission in patients with autoimmune diseases. METHODS: French multicenter retrospective study including patients presenting DAH related to autoimmune diseases requiring ICU admission from 2000 to 2016. RESULTS: One hundred four patients (54% of men) with median age of 56 [32-68] years were included with 79 (76%) systemic vasculitis and 25 (24%) connective tissue disorders. All patients received steroids, and 72 (69%), 12 (11.5%), and 57 (55%) patients had cyclophosphamide, rituximab, and plasma exchanges, respectively. During ICU stay, 52 (50%), 36 (35%), and 55 (53%) patients required mechanical ventilation, vasopressor use, and renal replacement therapy, respectively. Factors associated with mechanical ventilation weaning were age (HR [95%CI] 0.97 [0.96-0.99] per 10 years, p < 0.0001), vasculitis-related DAH (0.52 [0.27-0.98], p = 0.04), and time from dyspnea onset to ICU admission (0.99 [0.99-1] per day, p = 0.03). ICU mortality was 15%. Factors associated with alive status at ICU discharge were chronic cardiac failure (HR [95%CI] 0.37 [0.15-0.94], p = 0.04), antiphospholipid syndrome-related DAH (3.17 [1.89-5.32], p < 0.0001), SAPS II (0.98 [0.97-0.99], p = 0.007), and oxygen flow at ICU admission (0.95 [0.91-0.99] per liter/min, p = 0.04). CONCLUSION: DAH in autoimmune diseases is a life-threatening complication which requires mechanical ventilation in half of the cases admitted to ICU.

Ultra-Protective Ventilation Reduces Biotrauma in Patients on Venovenous Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome.

INTRODUCTION: Ventilator settings for patients with severe acute respiratory distress syndrome supported by venovenous extracorporeal membrane oxygenation are currently set arbitrarily. The impact on serum and pulmonary biotrauma markers of the transition to ultra-protective ventilation settings following extracorporeal membrane oxygenation implantation, and different mechanical ventilation strategies while on extracorporeal membrane oxygenation were investigated. DESIGN: Randomized clinical trial. SETTINGS: Nine-month monocentric study. PATIENTS: Severe acute respiratory distress syndrome patients on venovenous extracorporeal membrane oxygenation. INTERVENTIONS: After starting extracorporeal membrane oxygenation, patients were switched to the bi-level positive airway pressure mode with 1 second of 24 cm H2O high pressure and 2 seconds of 12 cm H2O low pressure for 24 hours. A computer-generated allocation sequence randomized patients to receive each of the following three experimental steps: 1) high pressure 24 cm H2O and low pressure 20 cm H2O (very high positive end-expiratory pressure-very low driving pressure); 2) high pressure 24 cm H2O and low pressure 5 cm H2O (low positive end-expiratory pressure-high driving pressure); and 3) high pressure 17 cm H2O and low pressure 5 cm H2O (low positive end-expiratory pressure-low driving pressure). Plasma and bronchoalveolar lavage soluble receptor for advanced glycation end-products, plasma interleukin-6, and monocyte chemotactic protein-1 were sampled preextracorporeal membrane oxygenation and after 12 hours at each step. MEASUREMENTS AND MAIN RESULTS: Sixteen patients on ECMO after 7 days (1-11 d) of mechanical ventilation were included. "Ultra-protective" mechanical ventilation settings following ECMO initiation were associated with significantly lower plasma sRAGE, interleukin-6, and monocyte chemotactic protein-1 concentrations. Plasma sRAGE and cytokines were comparable within each on-ECMO experimental step, but the lowest bronchoalveolar lavage sRAGE levels were obtained at minimal driving pressure. CONCLUSIONS: ECMO allows ultra- protective ventilation, which combines significantly lower plateau pressure, tidalvolume, and driving pressure. This ventilation strategy significantly limited pulmonary biotrauma, which couldtherefore decrease ventilator-induced lung injury. However, the optimal ultra-protective ventilation strategy once ECMO is initiated remains undetermined and warrants further investigations. (Crit Care Med 2019; 47:1505-1512).

Transvenous Renal Biopsy of Critically Ill Patients: Safety and Diagnostic Yield.

OBJECTIVES: Transvenous renal biopsy is an alternative way to obtain kidney samples from patients with bleeding risk factors (e.g., antiplatelet therapy and anticoagulation or coagulation disorders). This study was undertaken to determine the safety and diagnostic yield of transvenous renal biopsy of critically ill patients. DESIGN: Monocenter, retrospective, observational cohort study. SETTING: A 26-bed French tertiary ICU. PATIENTS: All patients undergoing in-ICU transvenous renal biopsy between January 2002 and February 2018. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Eighty patients (male/female sex ratio, 0.95; mean ± SD age, 47.3 ± 18.3 yr) were included. A histologic diagnosis was obtained for 77 patients (96.3%), with acute tubular necrosis being the most frequent: 23 (29.9%). A potentially treatable cause was found for 47 patients (58.7%). The numbers of patients with 0, 1, 2, or 3 factors (i.e., antiplatelet therapy, thrombopenia [< 150 G/L], and preventive or curative anticoagulation) at the time of the biopsy were, respectively: seven (8.8%), 37 (46.2%), 31 (38.7%), and five (6.3%). Four (5%) and two (2.5%) patients, respectively, had renal hematoma and macroscopic hematuria; none required any specific treatment. Six patients (7.5%) died in-ICU, and 90-day mortality was 8 of 80 (10%). No death was related to transvenous renal biopsy, and median biopsy-to-death interval was 38 days (interquartile range, 19.7-86 d). CONCLUSIONS: Based on this cohort of ICU patients with acute kidney injury, transvenous renal biopsy was safe and obtained a high diagnostic yield for these selected critically ill patients, even in the presence of multiple bleeding risk factors.