Severe asthma exacerbation: Changes in patient characteristics, management, and outcomes from 1997 to 2016 in 40 ICUs in the greater Paris area

Background

Despite advances in asthma treatments, severe asthma exacerbation (SAE) remains a life-threatening condition in adults, and there is a lack of data derived from adult patients admitted to intensive care units (ICUs) for SAE. The current study investigated changes in adult patient characteristics, management, and outcomes of SAE over a 20-year period in 40 ICUs in the greater Paris area.

Methods

In this retrospective observational study, admissions to 40 ICUs in the greater Paris area for SAE from January 1, 1997, to December 31, 2016 were analyzed. The primary outcome was the proportion of ICU admissions for SAE during 5-year periods. Secondary outcomes were ICU and hospital mortality, and the use of mechanical ventilation and catecholamine. Multivariate analysis was performed to assess factors associated with ICU mortality.

Results

A total of 7049 admissions for SAE were recorded. For each 5-year period, the proportion decreased over time, with SAE accounting for 2.84% of total ICU admissions (n=2841) between 1997 and 2001, 1.76% (n=1717) between 2002 and 2006, 1.05% (n=965) between 2007 and 2011, and 1.05% (n=1526) between 2012 and 2016. The median age was 46 years (interquartile range [IQR]: 32-59 years), 55.41% were female, the median Simplified Acute Physiology Score II was 20 (IQR: 13-28), and 19.76% had mechanical ventilation. The use of mechanical ventilation remained infrequent throughout the 20-year period, whereas the use of catecholamine decreased. ICU and hospital mortality rates decreased. Factors associated with ICU mortality were renal replacement therapy, catecholamine, cardiac arrest, pneumothorax, acute respiratory distress syndrome, sepsis, and invasive mechanical ventilation (IMV). Non-survivors were older, had more severe symptoms, and were more likely to have received IMV.

Conclusion

ICU admission for SAE remains uncommon, and the proportion of cases decreased over time. Despite a slight increase in symptom severity during a 20-year period, ICU and hospital mortality decreased. Patients requiring IMV had a higher mortality rate.

Placental growth factor level in plasma predicts COVID-19 severity and in-hospital mortality

BACKGROUND

Coronavirus disease 2019 (COVID-19) is a respiratory disease associated with vascular inflammation and endothelial injury.

OBJECTIVES

To correlate circulating angiogenic markers vascular endothelial growth factor A (VEGF-A), placental growth factor (PlGF), and fibroblast growth factor 2 (FGF-2) to in-hospital mortality in COVID-19 adult patients.

METHODS

Consecutive ambulatory and hospitalized patients with COVID-19 infection were enrolled. VEGF-A, PlGF, and FGF-2 were measured in each patient ≤48 h following admission.

RESULTS

The study enrolled 237 patients with suspected COVID-19: 208 patients had a positive diagnostic for COVID-19, of whom 23 were mild outpatients and 185 patients hospitalized after admission. Levels of VEGF-A, PlGF, and FGF-2 significantly increase with the severity of the disease (P < .001). Using a logistic regression model, we found a significant association between the increase of FGF-2 or PlGF and mortality (odds ratio [OR] 1.11, 95% confidence interval [CI; 1.07-1.16], P < .001 for FGF-2 and OR 1.07 95% CI [1.04-1.10], P < .001 for PlGF) while no association were found for VEGF-A levels. Receiver operating characteristic curve analysis was performed and we identified PlGF above 30 pg/ml as the best predictor of in-hospital mortality in COVID-19 patients. Survival analysis for PlGF confirmed its interest for in-hospital mortality prediction, by using a Kaplan-Meier survival curve (P = .001) and a Cox proportional hazard model adjusted to age, body mass index, D-dimer, and C-reactive protein (3.23 95% CI [1.29-8.11], P = .001).

CONCLUSION

Angiogenic factor PlGF is a relevant predictive factor for in-hospital mortality in COVID-19 patients. More than a biomarker, we hypothesize that PlGF blocking strategies could be a new interesting therapeutic approach in COVID-19.

Predictive Factor for COVID-19 Worsening: Insights for High-Sensitivity Troponin and D-Dimer and Correlation With Right Ventricular Afterload

Background: Coronavirus disease 2019 (COVID-19) has been associated with cardiovascular complications and coagulation disorders.

Objectives: To explore clinical and biological parameters of COVID-19 patients with hospitalization criteria that could predict referral to intensive care unit (ICU).

Methods: Analyzing the clinical and biological profiles of COVID-19 patients at admission.

Results: Among 99 consecutive patients that fulfilled criteria for hospitalization, 48 were hospitalized in the medicine department, 21 were first admitted to the medicine ward department and referred later to ICU, and 30 were directly admitted to ICU from the emergency department. At admission, patients requiring ICU were more likely to have lymphopenia, decreased SpO₂, a D-dimer level above 1,000 ng/mL, and a higher high-sensitivity cardiac troponin (Hs-cTnI) level. A receiver operating characteristic curve analysis identified Hs-cTnI above 9.75 pg/mL as the best predictive criteria for ICU referral [area under the curve (AUC), 86.4; 95% CI, 76.6–96.2]. This cutoff for Hs-cTnI was confirmed in univariate [odds ratio (OR), 22.8; 95% CI, 6.0–116.2] and multivariate analysis after adjustment for D-dimer level (adjusted OR, 20.85; 95% CI, 4.76–128.4). Transthoracic echocardiography parameters subsequently measured in 72 patients showed an increased right ventricular (RV) afterload correlated with Hs-cTnI (r = 0.42, p = 0.010) and D-dimer (r = 0.18, p = 0.047).

Conclusion: Hs-cTnI appears to be the best relevant predictive factor for referring COVID-19 patients to ICU. This result associated with the correlation of D-dimer with RV dilatation probably reflects a myocardial injury due to an increased RV wall tension. This reinforces the hypothesis of a COVID-19-associated microvascular thrombosis inducing a higher RV afterload.

Respiratory mechanics and gas exchanges in the early course of COVID-19 ARDS: a hypothesis-generating study

Rationale

COVID-19 ARDS could differ from typical forms of the syndrome.

Objective

Pulmonary microvascular injury and thrombosis are increasingly reported as constitutive features of COVID-19 respiratory failure. Our aim was to study pulmonary mechanics and gas exchanges in COVID-2019 ARDS patients studied early after initiating protective invasive mechanical ventilation, seeking after corresponding pathophysiological and biological characteristics.

Methods

Between March 22 and March 30, 2020 respiratory mechanics, gas exchanges, circulating endothelial cells (CEC) as markers of endothelial damage, and D-dimers were studied in 22 moderate-to-severe COVID-19 ARDS patients, 1 [1–4] day after intubation (median [IQR]).

Measurements and main results

Thirteen moderate and 9 severe COVID-19 ARDS patients were studied after initiation of high PEEP protective mechanical ventilation. We observed moderately decreased respiratory system compliance: 39.5 [33.1–44.7] mL/cmH₂O and end-expiratory lung volume: 2100 [1721–2434] mL. Gas exchanges were characterized by hypercapnia 55 [44–62] mmHg, high physiological dead-space (V_D/V_T): 75 [69–85.5] % and ventilatory ratio (VR): 2.9 [2.2–3.4]. V_D/V_T and VR were significantly correlated: r² = 0.24, p = 0.014. No pulmonary embolism was suspected at the time of measurements. CECs and D-dimers were elevated as compared to normal values: 24 [12–46] cells per mL and 1483 [999–2217] ng/mL, respectively.

Conclusions

We observed early in the course of COVID-19 ARDS high V_D/V_T in association with biological markers of endothelial damage and thrombosis. High V_D/V_T can be explained by high PEEP settings and added instrumental dead space, with a possible associated role of COVID-19-triggered pulmonary microvascular endothelial damage and microthrombotic process.

Angiopoietin-2 as a marker of endothelial activation is a good predictor factor for intensive care unit admission of COVID-19 patients

Background

Coronavirus disease-2019 (COVID-19), a respiratory disease has been associated with ischemic complications, coagulation disorders, and an endotheliitis.

Objectives

To explore endothelial damage and activation-related biomarkers in COVID-19 patients with criteria of hospitalization for referral to intensive care unit (ICU) and/or respiratory worsening.

Methods

Analysis of endothelial and angiogenic soluble markers in plasma from patients at admission.

Results

Study enrolled 40 consecutive COVID-19 patients admitted to emergency department that fulfilled criteria for hospitalization. Half of them were admitted in conventional wards without any ICU transfer during hospitalization; whereas the 20 others were directly transferred to ICU. Patients transferred in ICU were more likely to have lymphopenia, decreased SpO2 and increased D-dimer, CRP and creatinine levels. In those patients, soluble E-selectin and angiopoietin-2 were significantly increased (p value at 0.009 and 0.003, respectively). Increase in SELE gene expression (gene coding for E-selectin protein) was confirmed in an independent cohort of 32 patients using a whole blood gene expression profile analysis. In plasma, we found a strong association between angiopoetin-2 and CRP, creatinine and D-dimers (with p value at 0.001, 0.001 and 0.003, respectively). ROC curve analysis identified an Angiopoietin-2 cut-off of 5000 pg/mL as the best predictor for ICU outcome (Se = 80.1%, Sp = 70%, PPV = 72.7%, NPV = 77%), further confirmed in multivariate analysis after adjustment for creatinine, CRP or D-dimers.

Conclusion

Angiopoietin-2 is a relevant predictive factor for ICU direct admission in COVID-19 patients. This result showing an endothelial activation reinforces the hypothesis of a COVID-19-associated microvascular dysfunction.

Anti-parietal cell autoimmunity is associated with an accelerated decline of lung function in IPF patients

BACKGROUND

Autoantibodies against lung epithelial antigens are often detected in patients with Idiopathic Pulmonary Fibrosis (IPF). Anti-Parietal Cell Antibodies (APCA) target the H+/K+ATPase (proton pump). APCA prevalence and lung H+/K+ATPase expression was never studied in IPF patients.

METHODS

We retrospectively collected clinical, lung function and imaging data from APCA positive patients (APCA+IPF) and compared them with APCA negative IPF patients matched on the date of diagnostic assessment. H+/K+ATPase expression was assessed with immunohistochemistry and PCR.

RESULTS

Among 138 IPF patients diagnosed between 2007 and 2014 and tested for APCA, 19 (13.7%) APCA+ patients were identified. APCA+IPF patients were 16 men and 3 women, mean age 71 years. The median titer of APCA was 1:160. A pernicious anemia was present in 5 patients and preceded the fibrosis in 3 cases. With a mean follow up of 31 months, 2 patients had an exacerbation and 7 patients died. As compared with 19 APCA- IPF patients, APCA+IPF patients had a less severe disease with better DLCO (57% vs 43% predicted), preserved PaO₂ (85 ± 8 mmHg vs 74 ± 11 mmHg), a lower rate of honeycombing on HRCT (58% vs 89%), but they experienced an accelerated decline of FVC (difference 61.4 ml/year; p = .0002). The H+/K+ATPase was strongly expressed by hyperplastic alveolar epithelial cells in the fibrotic lung.

CONCLUSION

Anti-parietal cell autoimmunity is detected in some IPF patients and is associated with an accelerated decline of lung function. Anti-parietal cell autoimmunity may promote lung fibrosis progression.

[Inhalation therapy: inhaled corticosteroids in ENT, development and technical challenges of powder inhalers, nebulisers synchronized with breathing and aerosol size distribution. GAT aerosolstorming, Paris 2012]

The working group on aerosol therapy (GAT) of the Société de Pneumologie de Langue Française (SPLF) has organized its third Aerosolstorming in 2012. During one single day, different aspects of inhaled therapies have been treated and are detailed in two articles, this one being the second. This text deals with the indications of inhaled corticosteroids in ENT, the development and technical challenges of powder inhalers, the advantages and disadvantages of each type of technologies to measure the particle sizes of inhaled treatments.

Phase separation in molecular layers of macromolecules at the champagne-air interface

Bubble and foam stability, which are essential for the hallmark of champagne, rely on the concentration of amphiphilic macromolecules originating from the grape, which form molecular layers at the interface between champagne and gas. Ellipsometry and Brewster angle microscopy experiments were conducted at the air-champagne interface to analyse the lateral organization of the layers of macromolecules. Several kinds of phase separations - leading in some cases to two-dimensional foams - were identified. At the beginning of layer formation, condensed domains develop at the expense of dilute domains. Thereafter, phase separations occur within the condensed domains. These findings may allow advances in the implementation of methods predicting bubble and foam stability of champagnes.