these two scores in predicting HFNO failure by calculating the area under the receiver operating characteristic (ROC) curves (AUC).

**Results:** During the study-period, a total of 137 patients were admitted for covid-19 ARDS. From this cohort, we included 106 patients with a positive RT-PCR test and available chest CT scan. This population included 76 (71.7%) male and 30 (28.3%) female with a median age of 62.5 years (IQR 53.75–69). All patients were put under HFNO at admission of whom 29 (27.4%) patients required invasive mechanical ventilation. The most common lesions of the disease included ground glass opacities (GGO) present in 103 (97.2%) patients, followed by consolidations (n = 83, 78.3%) and crazy paving pattern (n = 62, 58.5%). Both scores were well correlated (Pearson correlation coefficient of 0.75). The AUC for Score 1 was 0.73 (95% CI 0.623–0.843) with a p value and the CT score 2 had an AUC of 0.81 (95% CI 0.719–0.911) with a p value of 0.000 (Fig. 1).

**Conclusion:** These data suggest the potential role of CT scores for predicting the ventilatory outcome of SARS-CoV-2 patients. Both scores had a good discrimination for patients with higher risk of intubation.

**Compliance with ethics regulations:** N/A.

<figure><img src="image_106.png" /><figcaption>ROC analysis of the score1 and score2 for prediction of requiring Invasive mechanical ventilation</figcaption></figure>

FC-247

Is Chest Computed Tomography in COVID-19 inpatients at the ICU predictive of severity?

GHIGO Zoé¹, SORIAL Didier¹, EMERY Malo¹, BABIN Matthias¹, CARREIRA Serge¹

¹Hopital Saint Camille, Bry-Sur-Marne, France

**Correspondence:** Zoé GHIGO (zoe.ghigo@gmail.com)

Annals of Intensive Care 2022, **12**(1):FC-247

**Rationale:** In December 2019, a new coronavirus, named SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), was discovered in the Hubei province of China, causing numerous cases of pneumonia in the World, to the point of getting the status of pandemic in March of 2020. Worldwide, the use of chest computed tomography (CT) to facilitate the management of the COVID-19 crisis has been uneven. Despite many scientific publications on COVID-19, very few of them have evaluated the prognostic use of CT at admission in the emergency room. Our study was conducted in order to determine a potential correlation between the percentage of lung damage on CT scans at admission in patients with positive COVID-19 RT-PCR and their prognosis.

**Patients and methods/Materials and methods:** This monocenter, observational, retrospective study aims to establish the prognostic

value of the CT scan at admission in the emergency room based on the percentage of lung damage on CT scans at admission. Our secondary goals were to determine the clinical characteristics of patients admitted in the emergency room with a COVID-19 infection, and to report the non-clinical characteristics associated with a poor prognosis.

**Results:** From March 3rd to May 9th 2020, 293 patients admitted at the emergency room or the ICU for a COVID-19 infection and who underwent through a CT scan at admission were included in our study. After splitting our population between 3 groups, based on the percentage of lung damage on the CT scans (<50%, >50%, atypical), we found that 42% of patients presenting more than 50% of lung damage on the CT scan at admission were deceased or admitted at the ICU 7 days after admission (versus 20% and 12% in the 2 other groups, p < 0.01). In multivariable analysis, the sole percentage of lung damage on CT scans was associated with a poor prognosis (RR 3.37 [1.6–7.12], p = 0.02). The interpretation of the CT scan is bound to an inter-individual variation (Kappa-Cohen coefficient going from 0.19 to 0.53). The severity score of the CT scan was better associated with prognostic 7 days post admission when the CT was read by an expert radiologist (AUC = 0.714), versus automated severity score (AUC = 0.675) or by the on-call radiologist (AUC = 0.657).

**Conclusion:** CT scans at admission for patients with a COVID-19 infection are useful to predict admission in the ICU or mortality 7 days post admission.

**Compliance with ethics regulations:** N/A.

FC-248

Role of echocardiography in the management and prognosis of patients admitted for acute respiratory failure in a Tunisian intensive care unit

MATOUK Iyed¹, HAMMOUDA Zeineb¹, BEDHIAFI Emir¹, BEN AHMED Hedia¹, Houri Fadwa¹, BOUGUEZZI Nabil¹, LAHMAR Manel¹, DACHRAOUI Fahmi¹, ABOUG Fekri¹, OUANES-BESBES Lamia¹

¹University Hospital Fattouma Bourguiba of Monastir (Tunisia), Monastir, Tunisie

**Correspondence:** Iyed MATOUK (maatouk.yed@gmail.com)

Annals of Intensive Care 2022, **12**(1):FC-248

**Rationale:** Echocardiography is a crucial tool for the management of patients admitted in intensive care units (ICUs). Indeed, it is widely available and non-invasive. It offers vital data for diagnosis and treatment of the most common pathological conditions encountered in critically ill patients such as acute respiratory failure (ARF). We aimed to determine the role of echocardiography in the diagnosis, therapeutic changes and prognosis among patients admitted for ARF.

**Patients and methods/Materials and methods:** We conducted a retrospective study in the ICU of a Tunisian University Hospital from January 2017 to June 2020. All patients aged over 18 years admitted for ARF and receiving at least one echocardiography in our department were included.

**Results:** A total of 346 patients received an ultrasound examination (476 echocardiography). Almost two thirds were male (72.5%). Median age was 65 [55, 72] years. The main medical history was respiratory diseases (61%). Fifty percent were under non-invasive ventilation and 48.3% under mechanical ventilation. Median duration of ventilation was 10 [5, 17]. Among the transthoracic echocardiography, 87.1% were performed within 48 h of admission. Main indication of echocardiography was suspicion of an increase in left ventricular filling pressures (38.7%) (mean E/E' ratio was 10.4 ± 3.6, and mean E/A ratio was 1.4 ± 0.8). The main abnormalities of echocardiographic examinations were right heart dysfunction and left ventricular diastolic dysfunction (47.7% and 46% respectively). Echocardiography allowed hemodynamic monitoring in 25.7%. Echocardiography changed or clarified the initial diagnosis in 67.9%. In total, 67.9% of patients received a therapeutic change after an echocardiographic examination mainly furosemide (42.3%) and limitation of vascular filling (36%). Mortality rate was 30.9%. Almost 10% of the patients had RV/LV ratio > 1. The majority of patients who survived (90.9%) had RV/LV ratio < 1 (p = 0.6). Mean LVFE was 52.3 ± 13.1 in patient who died and 56.7 ± 9.2 in
survivors (p = 0.002). Mean PAPS was 55.2 ± 16.5 in patient who died and 48.4 ± 13.2 in survivors (p = 0.05). The majority of patients who survived received a therapeutic change (64.4%) (p = 0.03).

**Conclusion:** Our study confirms the importance of echocardiographic examination in the diagnosis, hemodynamic monitoring, therapeutic changes, and prognosis in ICU, particularly in patients admitted for ARF. Thus, intensivists should have the necessary training for better patient management.

**Compliance with ethics regulations:** Yes in clinical research.

FC-249

Radiographic Assessment of Lung Edema (RALE) score, oxygenation and compliances to predict End-Expiratory Lung Volume and Outcomes in mechanically ventilated patients

CAMPFORT Maëva¹, OLIVIER Pierre-Yves¹, STUDER Antoine², PAVLOSKY Bertrand¹, LEPROVOST Pierre¹, DESPREZ Christophe¹, YVIN Elise¹, TAILLANTOU-CANDAU Mathilde¹, CHEAN Dara¹, COURTAIS Antonin¹, MERDJI Hamid², RICHARD Jean-Christophe¹, MEZIANI Ferhat², MERCAT Alain¹, BELONCLE François¹

¹CHU Angers, Angers, France; ²CHRU Strasbourg, Strasbourg, France

**Correspondence:** Maëva CAMPFORT (maevacampfort@gmail.com)

Annals of Intensive Care 2022, **12**(1):FC-249

**Rationale:** Beside oxygenation and respiratory mechanics, chest radiograph has been proposed to estimate the extent of lung injury and to predict the outcomes of mechanically ventilated patients at the bedside. The Radiographic Assessment of Lung Edema (RALE) score has thus been shown to correlate with edema in lung explants and with hypoxemia and survival in patients with acute respiratory distress syndrome (ARDS) (1). Its clinical value has however not yet been assessed in a general ICU population of mechanically ventilated patients with or without ARDS criteria. This study aimed to assess whether the RALE score can allow to predict the end-expiratory lung volume (EELV) and the outcomes in mechanically ventilated patients, differently from oxygenation or lung and respiratory system compliances.

**Patients and methods/Materials and methods:** All patients admitted to two ICUs and mechanically ventilated for any cause were prospectively enrolled. Gas exchange, respiratory mechanics (including esophageal pressure measurements), end-expiratory lung volume (EELV, using the nitrogen wash-out wash-in technique) and chest radiograph were assessed within 36 h after intubation when the patients were ventilated in volume-controlled ventilation (tidal volume = 6 mL/kg predicted body weight (PBW)) with a positive end-expiratory pressure of 5 cmH₂O. The RALE score, in which the four quadrants of the chest are scored on a numerical scale for extent of consolidation and density of opacification, was independently assessed by two investigators.

**Results:** 217 patients were enrolled (124 men (83%), age 65 [56–77] years). 104 patients (48%) had ARDS criteria according to the Berlin definition. The RALE score was 19.9 [8.5–31.0]. The RALE score, respiratory system compliance, lung compliance and $PaO_2/FiO_2$ ratio were well correlated to EELV/PBW ($r = -0.39, p < 0.001; r = 0.51, p < 0.001; r = 0.60, p < 0.001 and r = 0.41, p < 0.001, respectively$). The RALE score was lower in patients who survived at day 60 than in those who did not survive (16.5 [6.1–27.3] vs 22 [12.0–32.0], p < 0.05). The respiratory system compliance was not different between the survivors and the non-survivors at day 60 (48 [39–58] vs 46 [36–57] mL/cmH₂O, p = 0.32), neither was the lung compliance (83 [60–101] vs 73 [49–94] mL/cmH₂O respectively, p = 0.06). The $PaO_2/FiO_2$ ratio was lower in the survivors than in the non-survivors at day 60 (201 [147–263] vs 155, [103–257]), p < 0.05).

**Conclusion:** The RALE score measurement may allow to estimate the end-expiratory lung volume, similarly to the assessment of oxygenation or compliances and to predict mortality at day 60 in mechanically ventilated patients.

**Reference 1:** Warren MA, Zhao Z, Koyama T, Bastarache JA, Shaver CM, Semler MW, et al. Severity scoring of lung oedema on the chest radiograph is associated with clinical outcomes in ARDS. Thorax. 2018 Sep;73(9):840–6.

**Compliance with ethics regulations:** Yes in clinical research.

FC-250

Early measurement of alveolar epithelial and endothelial biomarkers in serum predicts the need for mechanical ventilation in patients with COVID-19 pneumonia

ALLARDET-SERVENT Jerome¹, HEZARD Nathalie², PISSIER Christel³, BENAROUS Lucas¹, HALFON Philippe¹, MEGE Jean-Louis⁴, ALESSI Marie-Christine², MORANGE Pierre²

¹HOPITAL EUROPEEN MARSEILLE, Marseille, France; ²HOPITAL DE LA TIMONE, Marseille, France; ³HOPITAL NORD, Marseille, France; ⁴INSTITUT HOSPITALO-UNIVERSITAIRE DE MALADIES INFECTIEUSES, Marseille, France

**Correspondence:** Jerome ALLARDET-SERVENT (j.allardetservent@hospital-european.fr)

Annals of Intensive Care 2022, **12**(1):FC-250

**Rationale:** Predicting early the need for mechanical ventilation (MV) during COVID-19 is highly relevant for triage. Biomarkers of alveolar epithelial and endothelial injuries might be helpful in this context. This study investigates the value of four biomarkers in patients hospitalized for moderate to severe COVID-19 pneumonia.

**Patients and methods/Materials and methods:** Fifty-four patients with laboratory confirmed COVID-19 pneumonia were prospectively included and compared to 20 healthy controls. The primary end-point was the need for MV during the stay. The concentrations of four biomarkers were measured in the serum within the first 48 h following hospital admission: Krebs von den Lungen 6 (KL-6), soluble receptor for advanced glycation end-products (sRAGE), angiopoietin-2 (ANG-2), and club cell protein 16 (CC-16). KL-6 was quantified by chemiluminescent enzyme immunoassay using the Lumipulse® analyzer (Fujirebio, Tokyo, Japan) and the three other biomarkers using enzyme linked immunosorbent assays (Quantikine® ELISA, R&D, Minneapolis, USA). All measurements by ELISA were duplicated and averaged. Biomarkers concentrations were compared between three groups (controls, COVID-No MV and COVID-MV) using the Kruskal–Wallis test with Conover post-hoc comparisons. Receiver operating characteristic (ROC) analysis was used to determine the area under the curve (AUC) of biomarkers to predict MV requirement and the best cut-off was determined using the Youden index method. Continuous data are presented as median and interquartile.

**Results:** COVID-19 patients were mostly male (76%), aged 63 [53,71] years, and 21 (39%) were obese. Eighteen COVID-19 patients (33%) received standard oxygen therapy in the ward while 36 (67%) required ICU admission. Among ICU patients, 13 (24%) received high flow oxygen therapy and 23 (43%) required MV. Four patients received extracorporeal membrane oxygenation. Seven patients (13%) deceased. Compared to healthy controls, the concentrations of KL-6 and sRAGE were higher in both group of COVID-19 patients (Fig. 1). ANG-2 was higher in COVID-MV than controls. CC-16 did not increase in COVID-19 patients. Among COVID-19 patients, those requiring MV had higher levels of KL-6, sRAGE and CC-16 compared to the others. Three biomarkers (sRAGE, CC-16 and KL-6) were predicting the need for MV but the sRAGE performed better with an AUC of 0.786 for a cut-off above 5449 pg/mL.

**Discussion:** This study is the first to compare the performance of four biomarkers. We observed similar range of KL-6 than others¹ but higher sRAGE levels in MV patients².

**Conclusion:** sRAGE, KL-6 and ANG-2 concentrations are increased in the serum of patients with COVID-19 pneumonia but sRAGE best predict the need for MV.

**Reference 1:** d'Alessandro, M et al. Serum KL-6 Concentrations as a Novel Biomarker of Severe COVID-19. J Med Virol 2020, 92 (10), 2216–2220.

**Reference 2:** Kapandji, N et al. Importance of Lung Epithelial Injury in COVID-19-Associated Acute Respiratory Distress Syndrome: Value of Plasma Soluble Receptor for Advanced Glycation End-Products. Am J Respir Crit Care Med 2021, 204 (3), 359–362.

**Compliance with ethics regulations:** Yes in clinical research.
<figure><img src="image_107.png" /></figure>

Biomarkers concentrations in the serum of healthy controls and COVID-19 patients. A: Box blot of biomarkers levels among controls, COVID-19 patients not requiring MV (COVID-No MV) and those requiring MV (COVID-MV). B: ROC curves to predict MV. \*p < 0.05.

## FC-251

### Optimum time to initiate awake prone positioning in SARS-CoV-2 pneumonia to improve outcome

TRIFI Ahlem¹, MASSEOUD Lynda¹, OUHIBI Asma¹, TLILI Bedis¹, ABDENNEBI Cyrine¹, DALY Foued¹, TOUIL Yosr¹, ABDELLATIF Sami¹, BEN LAKHAL Salah¹
¹Medical Intensive Care Unit, Teaching Hospital la Rabta, Faculty of Medicine of Tunis, Tunis, Tunisie

**Correspondence:** Ahlem TRIFI (trifahlem2@gmail.com)

Annals of Intensive Care 2022, **12**(1):FC-251

**Rationale:** In patients with hypoxemic SARS-CoV-2 pneumonia, it becomes conventional that awake prone positioning (APP) under high nasal flow cannula (HNFC) improves oxygenation, reduces the need for mechanical ventilation (MV) and improve survival. And the earlier it was, the better outcome would be. But what about the optimum time to initiate APP in this kind of patients? Our aim was to determine the best time to initiate APP in hypoxemic SARS-CoV-2 pneumonia.

**Patients and methods/Materials and methods:** Prospective and analytical study including adult patients with acute hypoxemic confirmed SARS-CoV-2 pneumonia who received APP for at least one hour from HNFC administration. APP initiation times and all outcome parameters (primary: survival and secondary: MV use and ROX index) were recorded and compared. The optimum delay to initiate APP was determined by the ROC curve.

**Results:** We included 40 patients (31 male) with, a median age of 57 years, median SOFA of 4, and median signs onset of 11 days. Of them, 32.5% were obese, 37.5% have hypertension, 32.5% were diabetic and 5% were fully vaccinated. The intubation and death rates were respectively 45% and 50%. The median time to initiate APP from HNFC was 7,5 h [0–48] with extremes at 0 and 192 H. The number of APP sessions per day was at 2 [1–3] for a median duration at 4 h [2–6]. The time of APP from HNFC was significantly lower in survivors (n = 20) versus non survivors (n = 20) (14 [6–18] versus 48 [20–72], p = 0,033 respectively). Similarly, it was significantly lower in patients who not required MV (n = 22) (12.5 [4–14.75] versus 33 [18–72], p = 0.044 respectively). The best cutoff of APP from HNFC we showed predictor of survival was at 15 h with AUC/ROC = 0.725 ([0.563–0.887], p = 0.015), sensitivity at 65% and specificity at 85%. Initiating APP from HNFC within 15 h has less performance to predict the use of MV (AUC/ROC = 0.664 ([0.491–0.837], p = 0.07), sensitivity at 55.6% and specificity at 78%). Attached table displays the comparisons of the outcome's variables according to the cutoff of APP from HNFC that we found (early: < 15H (n = 25) versus late: > 15H (n = 15)). In the early APP group, survival was significantly better and MV use was lower. MV duration and ICU stay tended to be lower in this same group with an average gain of 36 h.

**Conclusion:** In patients with hypoxemic SARS-CoV-2 pneumonia, the positioning on APP within 15 h of HNFC improved survival and reduced the need of MV.

**Compliance with ethics regulations:** Yes in clinical research.
Table. Outcome's variables between early versus late APP from HNFC

<table><thead><tr><th>Variables</th><th>Early APP (&le;15H)<br>(n=25)</th><th>Late APP (&gt;15H)<br>(n=15)</th><th>p</th></tr></thead><tbody><tr><td>Survival, n (%)</td><td>17 (68%)</td><td>3 (20%)</td><td><strong>0,008</strong></td></tr><tr><td>MV use, n (%)</td><td>8 (32%)</td><td>10 (67%)</td><td><strong>0,05</strong></td></tr><tr><td>ROX Index, med [IQR] :</td><td></td><td></td><td></td></tr><tr><td>• Before APP</td><td>3,61 [2,55-4,42]</td><td>3,23 [2,66-3,8]</td><td>0,59</td></tr><tr><td>• After APP</td><td>3,8 [2,72-4,54]</td><td>3,2 [2,9-4]</td><td>0,17</td></tr><tr><td>HNFC duration (d), med [IQR]</td><td>5 [2-10]</td><td>6 [4-9]</td><td>0,15</td></tr><tr><td>Time for MV (d), med [IQR]</td><td>5,5 [1-7]</td><td>4 [3-5,5]</td><td>0,93</td></tr><tr><td>MV duration (d), med [IQR]</td><td>4 [3-6]</td><td>4,5 [6-8]</td><td><strong>0,07</strong></td></tr><tr><td>ICU-LOS</td><td>12 [10-16]</td><td>13,5 [11,5-18,5]</td><td><strong>0,07</strong></td></tr></tbody></table>

APP: awake prone position, HNFC: high nasal flow cannula, MV: mechanical ventilation, ICU: intensive care unit, LOS: length of stay

Outcome's variables between early versus late APP from HNFC

## FC-252

### Awake prone positioning for non-intubated patients with COVID-19 related acute hypoxemic respiratory failure: a systematic review and meta-analysis

PEREZ Yonatan¹, LI Jie², LUO Jian³, PAVLOV Ivan⁴, TAN Wei⁶, ROCA Oriol⁷, TAVERNIER Elsa¹⁷, KHARAT Aileen⁸, MACNICHOLAS Bairbre⁹, IBARRA-ESTRADA Miguel¹⁰, VINES David², BOSCH Nicholas A.¹¹, RAMPON Garrett¹², SIMPSON Steven Q.¹², WALKEY Allan J.¹¹, FRALICK Michael¹³, VERMA Amol¹⁴, RAZAK Fahad¹⁴, HARRIS Tim¹⁵, LAFFEY John G.⁹, GUÉRIN Claude¹⁶, EHRMANN Stephan⁵

¹Hôpital de Hautepierre, Hôpitaux Universitaires de Strasbourg, Strasbourg, France; ²Department of Cardiopulmonary Sciences, Division of Respiratory Care, Rush University, Chicago, Etats-Unis; ³Respiratory Medicine Unit and Oxford NIHR Biomedical Research Centre, NDM Experimental Medicine, University of Oxford, Oxford, Royaume-Uni; ⁴Department of Emergency Medicine, Hôpital de Verdun, Montréal, Canada; ⁵CHRU de Tours, Médecine Intensive Réanimation, Tours, France; ⁶Department of respiratory and critical care medicine, the First Affiliated Hospital, China Medical University, Shenyang, China; ⁷Servei de Medicina Intensiva, Hospital Universitari Vall d'Hebron, Barcelone, Espagne; ⁸Department of respiratory medicine, Geneva University Hospital, Genève, Suisse; ⁹Department of Anesthesia and Intensive Care Medicine, Galway University Hospitals and School of Medicine, National University of Ireland, Galway, Irlande; ¹⁰Unidad de terapia Intensiva, Hospital Civil Fray Antonio Alcalde, Guadalajara, Mexique; ¹¹Boston University School of Medicine and Boston Medical Center, Boston, Etats-Unis; ¹²University of Kansas Medical Center, Kansas City, Etats-Unis; ¹³Department of Medicine, Sinai Health System, and Department of Medicine, University of Toronto, Toronto, Canada; ¹⁴Li Ka Shing Knowledge Institute, St. Michael's Hospital, Unity Health Toronto, and Department of Medicine, University of Toronto, and Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Canada; ¹⁵Hamad Medical Corporation, Doha, Qatar; ¹⁶Médecine Intensive Réanimation, Hôpital Edouard Herriot, Lyon, France; ¹⁷Clinical Investigation Center, INSERM 1415, CHRU de Tours, Tours, France

**Correspondence:** Yonatan PEREZ (yonatperez@gmail.com)

Annals of Intensive Care 2022, **12**(1):FC-252

**Rationale:** Since the early phases of COVID-19 pandemic, prone positioning of non-intubated patients has been broadly utilized for patients with acute hypoxemic respiratory failure (AHRF) related to COVID-19. This intervention showed improvement of oxygenation. But the results of randomized controlled studies (RCTs) about intubation and mortality are contradictory. We aimed to assess the efficacy and safety of awake prone positioning (APP) including in relevant subpopulations.

**Patients and methods/Materials and methods:** We conducted a systematic review and meta-analysis according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations. Two independent groups of investigators searched MEDLINE, Embase, PubMed, Web of Science, Scopus, MedRxiv, BioRxiv, Google Scholar, and ClinicalTrials.gov for eligible studies from January
1st, 2020 to November 8th, 2021. RCTs comparing APP (intervention group) and supine position (control group) for non-intubated patients hospitalized for COVID-19 related AHRF were included. Random-effects meta-analysis was used to pool individual studies. Observational studies of APP comprising a control group were also included as a sensitivity analysis. Primary outcome was reported need for intubation. Secondary outcomes included: reported all-cause mortality, need for escalating respiratory support, Intensive Care Unit (ICU) admission, ICU length of stay, hospital length of stay and safety outcomes.

**Results:** 29 studies were included, with 10 RCTs comprising 1,985 patients and 19 non-RCTs totaling 2,669 patients. In 10 RCTs, compared to the supine position, APP significantly reduced the need for intubation in the overall population (risk ratio [RR] 0.84, 95% confidence interval [CI95] 0.72 to 0.97) (Fig. 2A). In the subgroup analysis, this significant reduction of intubation was observed in the studies with patients on advanced respiratory support (high-flow nasal cannula or noninvasive ventilation) at enrolment (RR 0.83, CI95 0.71 to 0.97), and those enrolled in ICU settings (RR 0.83, CI95 0.71 to 0.97) but not in patients receiving conventional oxygen therapy or enrolled in general wards. APP did not significantly reduce mortality (RR 1.00, CI95 0.70 to 1.44) (Fig. 2B). APP did not demonstrate a benefit on need for escalation of respiratory support, ICU admission, ICU and hospital length of stay. No serious adverse events associated with APP (in particular, cardiac arrest) were reported.

**Conclusion:** This systematic review and meta-analysis found that in patients with COVID-19 related AHRF, APP reduced the need for intubation, particularly in those patients requiring advanced respiratory support at enrollment and in those enrolled in the ICU but did not demonstrate a benefit on mortality and others secondary outcomes.

**Compliance with ethics regulations:** Yes in clinical research.

## A Intubation

<figure><img src="image_108.png" /></figure>

## B Mortality

<figure><img src="image_109.png" /></figure>

Intubation and mortality for RCTs

## FC-253

### Extended prone positioning duration for COVID-related ARDS: a retrospective study

WALTER Thaïs¹, ZUCMAN Noémie¹, MULLAERT Jimmy²,⁴, THIRY Ingrid¹, GERNEZ Coralie¹, ROUX Damien¹,³, RICARD Jean-Damien¹,⁴

¹AP-HP, Hôpital Louis Mourier, DMU ESPRIT, Service de Médecine Intensive Réanimation, Colombes, France; ²Department of Epidemiology, Biostatistics and Clinical Research, AP-HP, Hôpital Bichat, Paris, France;

³Université Paris Cité, Institut Necker-Enfants Malades, INSERM U1151, CNRS UMR 8253, Paris, France; ⁴Université Paris Cité, UMR1137 IAME, INSERM, Paris, France

**Correspondence:** Thaïs WALTER (thais.walter10@gmail.com)

Annals of Intensive Care 2022, **12**(1):FC-253

**Rationale:** During the COVID-19 pandemic, many more patients were turned prone than before, resulting in a considerable increase in workload. Whether extending duration of prone position may be beneficial has received little attention. We report here benefits and detriments of a strategy of extended prone positioning duration for COVID-19 related acute respiratory distress syndrome (ARDS).

**Patients and methods/Materials and methods:** Retrospective, monocentric, study on intensive care unit patients with COVID-19 related ARDS who have been treated with at least one session of prone positioning session of duration greater or equal to 24 h. When prone positioning sessions were initiated, patients were kept prone for a period that covered two nights. They were put back in the supine position around 11 AM the morning following the second night. Demographic data, data regarding the incidence of pressure injury and ventilation parameters were collected retrospectively on medical and nurse files of charts.

**Results:** For the 81 patients included, the median duration of prone positioning sessions was 39 h (interquartile range (IQR) 34–42) and patients benefited from a median of 2 sessions (IQR 1–4). The cumulated incidence of grade ≥ II pressure injuries was 26% (95%CI 17–37) and 2.5% (95% CI 0.3–8.8) for stages III/IV pressure injuries. This increased duration was associated with additional increase in oxygenation after 16 h with the PaO2/FiO2 ratio increasing from 150 mmHg (IQR 121–196) at H+16 to 162 mmHg (IQR 124–221) before being turned back to supine (p = 0.017) (Fig. 1). For 213 (94%) of prone positioning sessions, patients were turned over to supine position during daytime, i.e. between 9 AM and 6 PM. In comparison, had prone positioning sessions lasted strictly for 16 h, half of them (n = 117, 52%) would have required a turning back to supine between 6 PM and 9 AM, i.e. during night shifts.

**Discussion:** In an ancillary study of an international randomized trial evaluating prone positioning in ARDS, a cumulated incidence of 25% of patients presenting for the first time a pressure injury of stage ≥ II between day 1 and ICU discharge was reported (1). This is in line with our findings of a cumulated incidence of 26%.

**Conclusion:** Given the number of patients requiring prone position because of COVID-19-related ARDS, our results may have significant impact on both intensive care unit staffing and organizational issues, and could improve ventilatory parameters.

**Reference 1:** for the Proseva trial group, Girard R, Baboi L, Ayzac L, Richard J-C, Guérin C. The impact of patient positioning on pressure ulcers in patients with severe ARDS: results from a multicentre randomised controlled trial on prone positioning. Intensive Care.

**Compliance with ethics regulations:** Yes in clinical research.
<figure><img src="image_110.png" /><figcaption>Figure 1 Physiological parameter's changes during proning sessions.</figcaption></figure>

FC-254

Impact of prone position on renal function in the critical covid19 patient

MOUNIR Anass¹, NAANANI Karima¹, CHABBAR Sara¹, ELOUDGHIRI Ayman¹, CHERKAB Rachid¹, EL KETTANI ELHAMDI Chafik¹, BARROU Lahoucine¹

¹Réanimation Pavillon 17, CHU IBNROCHD, Casablanca, Maroc

**Correspondence:** Karima NAANANI (naananik@gmail.com)

Annals of Intensive Care 2022, **12**(1):FC-254

**Rationale:** Prone position [PP] is a method that has been widely used in the management of severe ARDS in COVID19. The increase in intra-abdominal pressure during the prone position can promote dysfunction of certain organs, particularly the kidney. The aim of our study was to assess the impact of prone position on renal function by analyzing the variations of intra-abdominal pressure.

**Patients and methods/Materials and methods:** A prospective study of 56 patients with critical COVID19 under mechanical ventilation over a period of 6 months [September 2020–March 2021]. PP was adopted in all our patients, with intravesical pressure [IVP] measurements before and during PP. In addition to the measurement of hourly diuresis, we performed the determination of renal aggression markers, urea and plasma creatinine levels before, during and after PP.

**Results:** The mean age was 61.8 years. A clear male predominance was observed. The prone position allowed an improvement of the patients' oxygenation after the first PP session and after 3 sessions. We detected an increase in IVP in the prone position, which exceeded 12 mmHg and rose even higher to 60 mmHg or 68 mmHg in some patients. Renal aggression was observed in 32 patients from the first session of PP. 26 patients progressed to AKI, which represents 46.4% of our study population, with recourse to extrarenal epuration in 12 out of 26 patients. Univariate analysis allowed us to show that obesity [OR: 1.24, Pvalue: 0.004], with a high abdominal perimeter [OR: 1.194, CI: 1.19–31.674, Pvalue: 0.009], and critical parenchymal damage > 75% [OR: 3.203, CI: 1.049–9.811, Pvalue: 0.038] represent risk factors for progression to renal insufficiency. It was also shown that high intravesical pressure is significantly associated with renal failure [OR: 6.4, CI: 1.446–44.64, Pvalue: 0.002].

**Discussion:** The kidney is the most sensitive organ to increased IAP and is the first organ affected in case of intra-abdominal pressure. However, to date, no study in the literature has concretely established predictive factors of the occurrence of acute renal failure in the patient placed in prone position, after a severe COVID19.

**Conclusion:** Our study allowed us to emphasize the value of prone positioning in the severe or critical Covid19 patient. However, the use of PP requires an understanding of the risks, including intra-abdominal pressure and the risk of renal failure.

**Compliance with ethics regulations:** Yes in clinical research.

FC-255

Impact of Time-Controlled Adaptive Ventilation (TCAV) on hemodynamics in a swine ARDS model

PEQUIGNOT Benjamin¹, LESCROART Mickael¹, BITKER Laurent², PINA Héloïse¹, TRAN N'Guyen¹, HEBERT Jean-Louis³, RICHARD Jean-Christophe², LEVY Bruno¹, KOSZUTSKI Matthieu¹

¹CHRU de Nancy, VandœUvre-Lès-Nancy, France; ²Hôpital de la Croix

Rousse, Lyon, France; ³Institut de Cardiologie, Groupe Hospitalier

Pitié-Salpêtrière, Paris, France

**Correspondence:** Benjamin PEQUIGNOT (b.pequignot@chru-nancy.fr)

Annals of Intensive Care 2022, **12**(1):FC-255

**Rationale:** The current standard of care of severe ARDS is based on low tidal volume (VT), at 6 mL/kg of predicted body weight, and a positive end expiratory pressure (PEEP). An alternative strategy could be the time-controlled adaptive ventilation (TCAV) strategy, i.e. a specific settings of airway pressure release ventilation (APRV) mode. Initially reported by Habashi et al., TCAV relies on delivering a CPAP phase, followed by a brief expiratory release phase (1). TCAV leads to an increase in intra thoracic pressures and could be associated with hemodynamic impairment. The objective of our study was to compare hemodynamics between TCAV and conventional protective ventilation in a porcine ARDS model.

**Patients and methods/Materials and methods:** In ten pigs (63–73 kg) lung injury was induced by repeated saline lavages followed by 2 h of injurious ventilation. The animals were then randomized into two groups: 1) Volume-controlled ventilation (VCV) with a VT of 6 mL/kg and PEEP adjusted to a plateau pressure of 28 to 30 cmH₂O; 2) TCAV group with P-high set between 27–29 cmH₂O, P-low at 0 cmH₂O, T-low adjusted to terminate at 75% of the expiratory flow peak, and T-high at 3–4 s for I:E > 6:1.

**Results:** There was no difference between-group for arterial blood pressure, pulmonary blood pressure or cardiac output. No significant left ventricular inotropic or relaxation alteration was noticed under TCAV versus VCV. Both elastance and PaO₂:FiO₂ were consistent with a moderate to severe ARDS after a 2-h period of injuring ventilation. Levels of total PEEP were significantly higher in TCAV group. Driving pressure and elastance were significantly lower in the TCAV group than in VCV group in multivariate analysis.

**Discussion:** First, experimental ARDS induced significant hemodynamic changes mainly driven by hypoxemia-induced pulmonary vasoconstriction. Secondly, TCAV did not significantly impact systemic hemodynamics, despite of the increase in intrathoracic pressures. Thirdly, TCAV increased alveolar recruitment in this ARDS model. Concerning limitations: the study might have been underpowered to assess a clinically relevant effect of TCAV on hemodynamics. Improvement in elastance can be in relation with higher level of total PEEP and suggest alveolar recruitment but we did not perform any CT scan to verify this hypothesis. To finish, conventional protective group had a transpulmonary pressure above 15 cmH₂O at all times of interest which may also explained effect observed on hemodynamics parameters.
**Conclusion:** No safety signal was observed for hemodynamic adverse events in the TCAV group in this double hit ARDS swine model.

**Reference 1:** Habashi NM. Other approaches to open-lung ventilation: airway pressure release ventilation. Crit Care Med. 2005;33:S228–S240. https://doi.org/10.1097/01.CCM.0000155920.11893.37

**Compliance with ethics regulations:** Yes in animal testing.

<figure><img src="image_111.png" /><figcaption>Table of ventilatory and hemodynamics parameters.</figcaption></figure>

FC-256

Potential for Alveolar recruitment in Covid-19 related ARDS:
evaluation by the recruitment-to-inflation ratio (R/I) method

LAHMAR Manel<fnref n="1" />, BEN AHMED Hedia<fnref n="1" />, CHIHAOUI Abir<fnref n="1" />, BEDHIAF Amir<fnref n="1" />, HAMMOUDA Zeineb<fnref n="1" />, DACHRAOUI Fahmi<fnref n="1" />, ABROUG Fekri<fnref n="1" />, BESBES OUANNES Lamia<fnref n="1" />

**Correspondence:** Manel LAHMAR (firassmal4@gmail.com)

Annals of Intensive Care 2022, **12**(1):FC-256

**Rationale:** Optimizing alveolar recruitment by means of positive end-expiratory pressure (PEEP) is the cornerstone of ARDS ventilation. PEEP exposes nevertheless to alveolar distension, which is harmful in these patients. Hence, the actual effects of PEEP depend on the recruitment potential of the lung we should evaluate in every patient. Chen et al. recently validated in non-Covid-19 ARDS an index (R/I) allowing bedside assessment of the potential for alveolar recruitment (or overdistension). **Objective:** To characterize by R/I ratio the recruitment potential in an ARDS-Covid19 cohort.

**Patients and methods/Materials and methods:** a prospective study carried out between January and October 2021, including patients hospitalized consecutively for severe SDRA due to COVID-19 (PaO₂/FiO₂ ≤ 150 mmHg). All patients received a lung-protective ventilation. The R/I ratio was measured in the supine position and in the prone position. The threshold proposed by Chen et al. (0.5) was used to identify high recruiters and low recruiters.

**Results:** 23 patients were included. The median age was 62 years IQR [52–65], most patients were male (Sex ratio (H/F) = 1.87). The main chest computed tomography findings were ground-glass opacities only 13 (56.5%) or associated with consolidation 9 (39.1%). High Recruiters had isolated ground glass in 72.7% of cases. Whereas, low recruiters had more ground glass associated with condensations in 54.5%. All patients received a lung-protective ventilation. VT median was 380 ml [360–400], median PEEP and median Pplat were respectively 14 cmH₂O [10–15], 30 cmH₂O [29–30]. The median R/I index was 0.48 in supine and 0.65 in prone position. Eleven patients (47.8%) had recruitment potential (R/I ≥ 0.5) while 12 (52.2%) had non-recruiting lungs. Median plateau pressure was 30 (with extremes ranging from 25 to 32cmH₂O) and static compliance was 27.

**Conclusion:** This study confirms the high frequency of ARDS with low recruitment potential in C-ARDS. This characteristic imposes a "personalized" ventilation based on the individual pulmonary mechanics properties.

**Compliance with ethics regulations:** Yes in clinical research.

FC-257

Evaluation of alveolar recruitment in Covid-related ARDS:
Multiple P–V curves vs Recruitment/Inflation (R/I) index

LAHMAR Manel<fnref n="1" />

**Correspondence:** Manel LAHMAR (firassmal4@gmail.com)

Annals of Intensive Care 2022, **12**(1):FC-257

**Rationale:** PV curves have allowed a better understanding of the pathophysiology of ARDS and remain a reference for evaluating the potential for alveolar recruitment. Chen and al recently validated an index (R/I) using the "Single breath maneuver" technique in ARDS. This index assesses the potential for alveolar recruitment (or inflation) at the patient's bedside. Both methods give an estimate of the magnitude of lung volume recruited. We conducted this study to compare estimated lung recruitment provided by these two methods.

**Patients and methods/Materials and methods:** Prospective study conducted in 26 patients with covid ARDS mechanically ventilated in prone position. Two PEEP levels were studied, and EELV was measured at both levels, with the difference (ΔEELV)) reflecting PEEP induced lung volume changes. Alveolar recruitment was measured using multiple pressure–volume (PV) curves (Extend respirator, Taema, France), and compared to the estimation made b the new index (R/I). High and Low recruiters were separated based on median estimated recruited lung volume (Rec<sub>estim</sub>). Estimated and measured recruitments were compared using Spearman correlation and Bland–Altman method.

**Results:** The median age was 63 years IQR [52–66], with no difference between the groups. Median recruited lung volume (Rec mes) measured by the technique of P–V curves was 227 ml [IQR: 182–364]. By "Single breath maneuver" technique, the median volume recruited (Rec mes) was 410 ml [295–506]. The median index (R/I) in Low recruiters was 0.46 [0.33–0.71] vs 0.66 [0.57–0.89] in high recruiters. The ΔEELV and Recestim was higher in high recruiters than in low recruiters. Recruited volume measured by "Single breath maneuver" and the PV curves method were strongly correlated (biais = 79.95%CI: – 98.7; 211.8). The concordance of both methods is reported in the Fig. 1.

**Conclusion:** Bedside evaluation of lung recruitment can be performed by simple clinical tool such as single breath maneuver with acceptable bias.

**Compliance with ethics regulations:** Yes in clinical research.

Bland-Altman: Difference vs average

<figure><img src="image_112.png" /><figcaption>Bland–Altman plot of Recruited volume measured by "Single breath maneuver" and the PV curves</figcaption></figure>

<footnote n="1">¹CHU fattouma bourguiba Monastir, Monastir, Tunisie</footnote>

<footnote n="1">¹CHU fattouma bourguiba Monastir, Monastir, Tunisie</footnote>
FC-258

Prone position during veno-venous extracorporeal membrane oxygenation in COVID-19 ARDS

TEXTORIS Laura¹, GRAGUEB-CHATTI Ines¹, MICKAEL Bobot¹,², DAVIET Florence¹, THEPENIER Mathieu¹, PILARCZYK Estelle¹, SALMI Saida¹, PINGLIS Camille¹, VALERA Sabine¹, SANZ Celine¹, AMALRIC Matthieu¹, SYLVESTRE Aude¹, PERES Noemie¹,³, ARGENONE Fabien¹,⁴, STEIN Claire¹, BAILLEUL Clotilde¹, FOREL Jean-Marie¹, ROCH Antoine¹, HRAIECH Sami¹, PAPAZIAN Laurent¹, GUERVILLY Christophe¹

¹Médecine Intensive Réanimation, CHU Hôpital Nord, AP-HM, Marseille, France; ²Centre de Néphrologie et Transplantation Rénale, CHU de la Conception, AP-HM, Marseille, France; ³Réanimation, Hôpital Sainte Musse, Toulon, France; ⁴Réanimation, Centre Hospitalier de Digne-les-Bains, Digne-Les-Bains, France

**Correspondence:** Christophe GUERVILLY (christophe.guervilly@ap-hm.fr)

Annals of Intensive Care 2022, **12**(1):FC-258

**Rationale:** Veno-venous Extra-Corporeal Membrane Oxygenation (vv-ECMO) has been extensively used for severe Acute Respiratory Distress Syndrome (ARDS) related to COVID-19 in case of prone position (PP) failure. A recent meta-analysis on observational studies suggests to continue PP while on vv-ECMO both in classical ARDS and COVID-19 related ARDS (CARDS). PP could mitigate ventilator induced lung injuries even during low volume, low pressure ventilation facilitated by vv-ECMO. Objectives were to investigate respiratory mechanics and physiological effects of PP and to assess safety in severe CARDS patients during vv-ECMO.

**Patients and methods/Materials and methods:** We performed a prospective observational cohort study in COVID-19 patients supported by vv-ECMO in the ECMO center of a tertiary university hospital in Marseille. All patients were deeply sedated and received continuous infusion of neuromuscular blockers during PP. We compared respiratory mechanics, ECMO and ventilator settings, gas exchanges and hemodynamics in supine, start of PP, end of PP and back to supine with analysis of variance.

**Results:** We included 25 patients with a range of 2 to 17 PP totaling 120 PP in the COVID-19 cohort. All patients had PP before ECMO consideration. ECMO was indicated after a median (IQR) of 5 (1-7) days of mechanical ventilation with PaO₂: FiO₂ of 68 (50-74) mmHg. ECMO weaning was achieved in 72%. ICU and hospital survival was 52%. First PP was performed after 2 (1-3) days of ECMO during 16 h. At baseline, very low tidal volume of 2.5 (2-3.5) ml/kg/PBW with a PEEP of 12 (10-15) cmH₂O targeting a plateau pressure of 25 (21-26) cm H₂O were used. We did not find significant changes in respiratory mechanics and gas exchanges during or after first PP. In particular, respiratory system compliance remains low at 11 (10-17) before and 11 (9-17) cm H₂O after PP. PaO₂ was respectively 75 (61-81), 78 (69-85), 77 (70-83) and 77 (67-89) mmHg at baseline supine, start of PP, end of PP and back to supine, (p=0.33) at a constant ECMO blood flow (3.8 to 4 L/min) and membrane lung fraction of 1. Concerning safety, we did not observe severe adverse events during PP. Only 3 (2.5%) of PP were interrupted for respiratory or hemodynamics worsening.

**Conclusion:** PP is feasible and safe during vv-ECMO for severe CARDS. Potentials benefits could be explained by mechanism not identified in this study.

**Compliance with ethics regulations:** Yes in clinical research.

FC-259

High-flow nasal oxygen therapy decrease the risk of mortality and the use of invasive mechanical ventilation in patients with severe SARS-CoV-2 pneumonia? A retrospective and comparative study of 265 cases

ALKOUH Rajae¹, EL RHALETE Abdelilah¹, MERBOUH Manal¹, EL AIDOUNI Ghizlane¹, BERRICHI Samia¹, TAOUHAR Salma¹, AFTISS Fatima Zahra¹, BKIYAR Houssam¹, ABDA Naima¹, HOUSNI Brahim¹

¹CHU Mohammed VI OUJDA, Oujda, Maroc

**Correspondence:** Rajae ALKOUH (alkouhrajae1993@gmail.com)

Annals of Intensive Care 2022, **12**(1):FC-259

**Rationale:** To evaluate the efficacy of high-flow nasal oxygen (HFNO) versus non-invasive ventilation in COVID-19.

**Patients and methods/Materials and methods:** This is a retrospective and comparative study conducted over a period of 10 months from March 2020 to December 2020 and involving 600 patients hospitalized in the intensive care unit of the CHU Mohammed VI of Oujda for the management of acute respiratory failure caused by COVID-19.

**Results:** Out of 600 patients with acute respiratory failure, 265 patients were included in the analyses. 162 (61.10%) patients were treated with HFNO, the intubation rate was 49.7% (80 patients out of 162) of which 63 died intubated (78.8%). Concerning the 82 non-intubated patients, only 16 died (19.8%). The total number of patients who received NIV was 71 (26.8%), 33 (46.5%) required mechanical ventilation. In-hospital mortality in patients treated with NIV was 100%. The difference in mortality outcome between the two groups was significantly (P < 0.0001) reduced in HFNO.

**Conclusion:** Treatment with high-flow oxygen improved survival in patients with acute hypoxemic respiratory failure compared with non-invasive ventilation, although no difference was observed in intubation rate.

**Compliance with ethics regulations:** Yes in clinical research.

FC-260

Predicting factors for the failure of high flow nasal cannula (HFNC) in COVID-19 related Acute Respiratory Distress Syndrome (ARDS)

BEDHIAFI Amir¹, TOUMI Radhouane¹,², MATOUK Iyed¹, BOUGUEZZI Nabil¹, ZGHIDI Marwa¹,², MEDDEB Khaoula¹,², BEN SAIDA Imen¹,², BOUSSARSA Mohamed¹,²

¹Medical Intensive Care Unit, Farhat Hached University Hospital, Sousse, Tunisie; ²Research Laboratory N° LR12SP09. Heart Failure. Farhat Hached University Hospital, University of Sousse, Sousse, Tunisie

**Correspondence:** Amir BEDHIAFI (bedhiafi.emir@gmail.com)

Annals of Intensive Care 2022, **12**(1):FC-260

**Rationale:** HFNC in widely used as a first line respiratory support in severe to critical COVID-19 pneumonia. We aimed to investigate factors associated with failure of HFNC in the management of COVID19 related ARDS (CARDS).

**Patients and methods/Materials and methods:** In this single-center study conducted in a 20-bed adult-ICU, consecutive admission for CARDS were screened for eligibility. Patients who underwent invasive mechanical ventilation (IMV) within 6 h upon admission were excluded. We collected clinical data and lab findings from admission until HFNC weaning or intubation which defined HFNC failure. ROX index was recorded at H0, H2, H6, H12 and H24. We also measured PF ratio evolution, monitored FiO₂ and respiratory rate (RR). High work of breathing (HWOB) was defined as a respiratory rate (RR) above 30 cpm and/or excessive accessory muscle use.

**Results:** 230 patients were included until August 2021. 61.5% (n=141) men, median aged 62 years [IQR 53-70] with SAPS-II at 28±8, PF ratio 132±63.8 under FiO₂ 0.72±0.23 on admission. 42% had hypertension, 41.3% diabetes and 32.2% obesity. 55.2% (n=127) successfully weaned from HFNC with a survival rate at 18% among those ongoing IMV. HFNC failure was associated to: higher SAPS II (32±7.4 vs 24.7±7, p<0.001) obesity (47% vs 27%, p=0.001) and compromised oxygenation parameters on admission: high FiO₂ (0.84±0.17 vs 0.6±0.21), RR (29.7±4.6 vs 25.6±3.7, p=0.001), presence of HWOB (67% versus 17%, p<0.001) and lower PF-ratio (101±48.6 vs 157.5±64.2, p<0.001). Sub-group analysis following PF-ratio showed higher success rate in mild-to-moderate compared to severe ARDS (85.7%, 65.2% and 27.6% respectively, p=0.001). ROX-index was significant at H6, H12 and H24 to predict HFNC failure. ROC analysis showed a higher specificity and sensitivity for H12 and H24 (AUC 0.906 IC 95% [0,864-0.948] and 0.944 IC 95% [0,908-0.981] respectively, p < 0.001) [Fig. 1]. Thirty percent (n=69) required non-invasive positive pressure ventilation at day 2.1 ± 1.3 alternating with HFNC and had higher failure rate (88.4% vs 26.1%, p < 0.001). Eighty seven percent (n=200) performed prone position while under HFNC with a higher associated success rate (58% vs 33%, p=0.01).
**Conclusion:** HFNC appears to be safer in mild-to-moderate CARDS especially when combined to prone position. ROX index, PF-ratio and WOB monitoring are reliable predictors for HFNC failure. More studies might be needed to confirm these results.

**Compliance with ethics regulations:** Yes in clinical research.

<figure><img src="image_113.png" /><figcaption>ROC curves and AUC of ROC index measurement for prediction of HFNC failure</figcaption></figure>

## FC-261

### Comparison of three noninvasive oxygenation strategies on outcomes in critically ill patients admitted for Covid-19 pneumonia: a retrospective multicenter cohort study

CHELLY Jonathan¹, COUPRY Louis-Marie², VONG Ly Van³, KAMEL Touffik⁴, MARZOUK Medhi⁵, TERZI Nicolas⁶, BRUEL Cedric², AUTRET Aurélie¹, GARNERO Aude¹, ARNAL Jean-Michel¹

¹Centre Hospitalier Intercommunal Toulon La Seyne sur Mer Toulon, France; ²Groupe Hospitalier Sud Ile de France, Melun, France; ³Grand Hôpital de l'Est Francilien, Jossigny, France; ⁴Centre Hospitalier Régional d'Orléans, Orléans, France; ⁵Centre Hospitalier de Béthune, Béthune, France; ⁶Centre Hospitalier Universitaire de Grenoble, Grenoble, France; ⁷Hôpital Saint-Joseph, Paris, France.

**Correspondence:** Jonathan CHELLY (jonathan.chelly@ch-toulon.fr)

*Annals of Intensive Care* 2022, **12**(1):FC-261

**Rationale:** Noninvasive respiratory support (NIRS) is recommended as the first line to reduce the need of invasive mechanical ventilation (MV) and its associated complications and high mortality in patients affected by Covid-19 pneumonia admitted in the intensive care unit (ICU). However, the optimal first-line noninvasive strategy to support oxygenation and ventilation is still debated.

**Patients and methods/Materials and methods:** We conducted a retrospective multicenter study in 7 French ICUs, including all consecutive adults admitted between July and December 2020 with a documented SARS-CoV-2 acute respiratory failure (PaO₂/FiO₂ < 300 mmHg), and treated either with high-flow nasal therapy (HFNT) alone, or non-invasive ventilation (NIV) combined or not with HFNT or continuous positive airway pressure combined or not with HFNT (CPAP). Patients who received both NIV and CPAP and those who were intubated within the 12 first hours after ICU admission were excluded. The primary outcome was the NIRS failure, defined as the need of endotracheal intubation or death in the ICU without endotracheal intubation.

**Results:** Among the 355 included patients, 160 (45%) were treated with HFNT alone, 115 (32%) with NIV and 80 (22%) with CPAP. NIV and CPAP were combined with HFNT in 97 (84%), and 79 (99%) patients, respectively. Median age (67 [58–75] years), body mass index (29 [25–33] kg/m²), SAPS-2 (42 [32–57]) and PaO₂/FiO₂ (130 [93–167]) on

admission were similar between groups whereas Charlson comorbidity index was lower when HFNT was used alone compared to NIV and CPAP. The primary outcome occurred in 158 (45%) patients with a statistical difference between HFNT alone, NIV, and CPAP groups (41%, 59%, and 31%, respectively; p < 0.001). Compared to patients who were treated with HFNT alone or NIV, those who were treated with CPAP had a lower incidence of the primary outcome on day 28 after ICU admission (p = 0.002) whereas ICU mortality was similar between groups (p = 0.20).

**Conclusion:** Among patients admitted for Covid-19 pneumonia in ICU and treated with NIRS, outcome seems to differ according to the strategy. More studies are warranted to compare such NIRS and identify the optimal treatment.

**Compliance with ethics regulations:** Yes in clinical research.

## FC-262

### Using CPAP in patients with SARS-CoV-2 hypoxemic pneumonia outside intensive care unit

ESSAFI Fatma¹,², ESSAGHAYER Salma¹,², GLENZA Iheb¹,², TALIK Imen¹,², BEN ISMAIL Khaoula¹,², KADDOUR Moez¹,², BAYOUDH Aida³, FESSI Ilhem³, JERBI Tahani⁴, CHKIRBENE Mariem⁵, MERHABENE Takoua¹,²

¹Intensive Care Unit, Regional Zaghouan's Hospital, Zaghouan, Tunisia;

²Faculty of medicine of Tunis, Tunis El-Manar university, Tunis, Tunisia;

³Pneumology department, Regional Zaghouan's Hospital, Zaghouan, Tunisia; ⁴Pharmacy department, Regional Zaghouan's Hospital, Zaghouan, Tunisia

**Correspondence:** Fatma ESSAFI (fatma.essafi@fmt.utm.tn)

*Annals of Intensive Care* 2022, **12**(1):FC-262

**Rationale:** Use of continuous positive airway pressure (CPAP) has been recommended in the management of patients with acute respiratory failure related to COVID-19 infection. However, its impact on mortality, length of hospital stay and the occurrence of complications have not been elucidated especially when delivered outside of a traditional critical care environment. Through this study, we propose to investigate the role of CPAP in the management of hypoxemic pneumonia due to SARS-CoV-2 in a pneumology department.

**Patients and methods/Materials and methods:** We reviewed retrospectively all data of consecutive confirmed COVID-19 patients receiving CPAP for the treatment of respiratory failure secondary to COVID-19. Patients admitted from 1st June to 31th August 2021 on the pneumology department of the regional hospital of Zaghouan, Tunisia were enrolled. Epidemiological, clinical and paraclinical data, complications and outcome were collected.

**Results:** During the study period, 205 patients were hospitalized, 65 of them required CPAP (31.7%). Median age was 64 years [34–87]. A clear male predominance was noted with sex ratio 1.5. Chronic heart disease, obesity, Diabetes mellitus, and chronic obstructive pulmonary disease were the most common comorbidities (55.4%; 38.5%, 27.7% and 10% respectively). Tobacco consumption was noted in 20% of patients. On admission, all patients had acute respiratory failure. Initial symptoms are essentially fever, nonproductive cough, dyspnea and gastrointestinal symptoms. The median time of symptoms at admission was 8.2 ± 3.6 days [1–20]. On initial examination, pulse air saturation ranged was 83.5 ± 8% [57–93] and oxygen requirements were 12 ± 6 L/min [6–30]. Four patients (6.2%) presented with acute hypertensive heart failure, requiring diuretic therapy. The predominant pattern of abnormality observed in chest CT was ground-glass opacification in 55 patients (84.6%), bilateral opacities in 27 patients (41.5%) and crazy paving in 17 patients (26.2%). Mean lung extension was estimated at 58 ± 20%. Mean duration of CPAP ventilation was 4 ± 3.2 days [1–18]. It was associated to high flow oxygen therapy in 43 patients and to conventional oxygen therapy in 22 patients. Awake prone position was applied in 39% of patients. Only one patient had developed care-related pneumonia. Mean length of hospital stay was 7.2 ± 4.8 days [1–21]. In hospital mortality was 32%. The outcome was favorable in 58 patients (66%).

**Conclusion:** CPAP represents a feasible and potentially efficient option for the treatment of respiratory failure in COVID-19. It can be delivered safely outside the traditional critical care, thus relieving pressure on critical care beds.
**Compliance with ethics regulations:** Yes in clinical research.

FC-263

**Predictive factors of high flow nasal cannula failure in critically ill COVID-19 patients admitted in a medical ICU for acute respiratory failure**

ZORGATI Hend¹, BEN BRAIEK Dhouha¹, HIDRI Rania¹, SAADAOUI Oussama¹, BEN MANSOUR Safa¹, MIGHRI Imen¹, DOUZI Arsalene¹, KAABI Chaïma¹, GHABI Oumaima¹, AZAZA Asma¹, BEN JAZIA Rahma², KACEM Amani², KHARRAT Imen², AYACHI Jihene¹

¹Service Réanimation Médicale, Hôpital Universitaire Ibn El Jazzar, Kairouan, Tunisie; ²Service Pneumologie, Hôpital Universitaire Ibn El Jazzar, Kairouan, Tunisie

**Correspondence:** Jihene AYACHI (ayachijihen@gmail.com)

Annals of Intensive Care 2022, **12**(1):FC-263

**Rationale:** High-Flow Nasal Cannula (HFNC) therapy appears to be effective to treat hypoxemic acute respiratory failure (ARF) patients during the outbreak of Coronavirus disease (COVID-19). However, there are few data about factors associated with HFNC failure in COVID-19 patients. Aim: To determine predictive factors associated with HFNC failure in COVID-19 patients admitted in medical intensive care unit (ICU) for ARF.

**Patients and methods/Materials and methods:** A 1 year observational, retrospective study performed from January 1st, 2021 to December 31st, 2021 in a 9-bed medical ICU at university hospital including adult patients admitted for hypoxemic ARF pneumonia secondary to SARS-CoV-2 and received HFNC on admission. Medical patients' charts were reviewed to collect demographic characteristics, underling diseases, severity at admission, clinical course and outcomes. Univariate and multivariate analysis were used to identify predictive factors associated with HFNC failure. HFNC failure was defined as mechanical ventilation (invasive or noninvasive) use.

**Results:** From 146 patients admitted for severe COVID-19 pneumonia, 128 (87.7%) received HFNC. Main characteristics were mean age, 51.05 ± 14.8 years; male predominance, 75 (58.6%) and 100 (78.1%) had at least one comorbidity. Median BMI and P/F ratio were: 31 [28-32]kg/m² and 92.75 [69-118.5]. Median SAPS II, SOFA and Charlson score were respectively: 23 [16-29]; 2 [2-4] and 1 [0-2]. HFNC parameters were median Flow at 52.5 [45-60]l/min and median FiO2 at 90 [70-100] %. The median ROX index at H1 and H24 were respectively at 4.26 [3.3-5.9] and 6.2 [4.5-8.4]. Awake prone position was performed in 105 (82%) of cases. HFNC failed in 43 (33.6%) patients, among them 32 (25%) were initially managed with non-invasive ventilation (NIV) with mortality rate at 35.2%. Univariate analysis identified the following factors for HFNC success and failure: elderly patient (7(8.2%) vs 17(39.5%), p = 0.000); cardiovascular comorbidity (7(8.2%) vs 9(20.9%), p = 0.04); Charlson index (0.5 [0-1] vs 2 [1-3], p = 0.000); SAPSII (19 [13-24] vs 29 [24-34.25], p = 0.000); SOFA (2 [1-4] vs 4 [2-8.5], p = 0.000); prone position (71(83.5%) vs 29(67.4%), p = 0.038); ROX index at H1(5 [3.8-6.04] vs 3.45 [3-4.57], p = 0.000); ROX index at H24 (7.73 [5.75-9.05] vs 4.2 [3.8-5.6], p = 0.000) and ROX index at day 6 (9.6 ± 3.5 vs 4.5 ± 1.4, p = 0.000). The multivariate logistic regression model identified ROX index at day 6 (OR, 0.3; 95% CI, [0.14-0.67]; p = 0.03) as a predictor factor of HFNC success.

**Conclusion:** ROX index at day 6 was the best predictor of HFNC failure in COVID-19 patients with hypoxemic AFR admitted in ICU.

**Compliance with ethics regulations:** Yes in clinical research.

FC-264

**Non-invasive ventilation in critically ill COVID-19 patients**

ALILA llef¹, KHARRAT Sana¹, HAFDHI Malek¹, BACCOUCH Najeh¹, JERBI Salma¹, BAHLOUL Mabrouk¹, BOUAZIZ Mounir¹

¹hospital Habib Bourguiba Sfax, Sfax, Tunisie

**Correspondence:** llef ALILA (ilefalila1323@gmail.com)

Annals of Intensive Care 2022, **12**(1):FC-264

**Rationale:** Non-invasive ventilation (NIV) was recommended for acute respiratory distress syndrome. A potential role for NIV to delay or avoid invasive mechanical ventilation (IMV) has emerged during the COVID-19 pandemic. The aim of this study was to explore the role of non-invasive ventilation in prediction of outcome in critically ill COVID-19 patients.

**Patients and methods/Materials and methods:** We conducted a retrospective study in a medical ICU over a period of 16 months [September 2020-December 2021] including patients with SARS-COV2 infection. The impact of non-invasive ventilation on complications and patient outcome was investigated.

**Results:** During the study period, 586 patients were included with a mean age of 59.5 ± 14.7 years and a gender ratio of 1.6. The median SAPSII and SOFA score were respectively of 29 ± 14.8 and 4 ± 2.6. Most patients had comorbidities, including hypertension (36%), obesity (32.1%) and diabetes (36.2%). 419 (71.5%) patients had severe acute respiratory distress syndrome (ARDS). Median ICU length of stay was 6 (IQR [3-10]) days and overall mortality was of 49% (287 patients). 378 patients (64.5%) needed NIV oxygenation. Of those who received NIV, 214 (57%) required IMV versus 50 (24%) of those not. Patients who received NIV developed more infections during their hospitalizations than those in the No-NIV group (220 (58%) vs 44 (21%); p < 0.001). Mortality was higher in patients receiving NIV (238 (63%) vs 49 (23%), p < 0.001). Length of stay was significantly longer in NIV group (Table I).

**Conclusion:** The use of NIV can predict morbidity and mortality in critically ill COVID-19 patients.

**Compliance with ethics regulations:** Yes in clinical research.

<table><caption>Table 1: Outcome comparison according to non-invasive ventilation.</caption><thead><tr><td></td><td>With NIV n=378</td><td>No NIV n=208</td><td>P</td></tr></thead><tbody><tr><td>Severe ARDS, n (%)</td><td>318 (84)</td><td>101 (48)</td><td>&lt;0.001</td></tr><tr><td>VMI, n (%)</td><td>214 (57)</td><td>50 (24)</td><td>&lt;0.001</td></tr><tr><td>Infection, n (%)</td><td>220 (58)</td><td>44 (21)</td><td>&lt;0.001</td></tr><tr><td>Length of stay, mean (days)</td><td>9±6.2</td><td>4.8±3.8</td><td>&lt;0.001</td></tr><tr><td>Mortality, n (%)</td><td>238 (63)</td><td>49 (23)</td><td>&lt;0.001</td></tr></tbody></table>

FC-265

**Comparison of two respiratory support strategies in critically ill patients admitted for Covid-19: a retrospective monocentric cohort study**

PAUL Timothé¹, CHELLY Jonathan¹, ARNAL Jean-Michel¹, GARNERO Aude¹

¹Centre Hospitalier Intercommunal Toulon La Seyne sur Mer - Hôpital

Sainte Musse, Toulon, France, Toulon, France

**Correspondence:** Timothé PAUL (paultimothe2@gmail.com)

Annals of Intensive Care 2022, **12**(1):FC-265

**Rationale:** Respiratory support for patients suffering for COVID-19 pneumonia in intensive care unit (ICU) is mandatory. During the first months of the outbreak, clinical trials have demonstrated that many oxygen strategies could delay intubation. However the outcomes between early and late intubation were not established in this particular kind of pneumonia.

**Patients and methods/Materials and methods:** We conducted a retrospective observational monocentric study in a French ICU including all consecutive adults with a documented SARS-CoV-2 acute respiratory failure (PaO₂/FiO₂ < 300 mmHg). Two periods were compared: the first included all patient admitted between February 2020 and June 2020, and an early intubation strategy was applied; the second period included all patients admitted between August 2020 and December 2020, and a non-invasive respiratory support strategy, using High-flow nasal canula, continuous positive airway pressure (CPAP), awake prone positioning and late intubation was applied. The primary outcome was the ICU length of stay. The secondary outcomes were complications, rate and duration of invasive ventilation and mortality in ICU.
**Results:** 47 patients were included in the first period and 96 in the second period. First period was associated with a longer ICU stay compared to the second period (11.00 [8.25–19.50] days versus 8.00 [4.75–14.25] days; p = 0,028). First period was associated with longer duration of respiratory support and higher intubation rate compared to the second (9 [9–16] days versus 7 [3–14] days; p = 0.338; 68% versus 25%; p < 0,001, respectively). The first period was associated with more complications such as hypotension, tracheotomy, critical illness neuromyopathy, ventilator associated pneumonia and thromboembolic complications whereas barotrauma and venovenous extracorporeal membrane oxygenation were no different between periods. ICU mortality was similar between periods (p = 0.814).

**Conclusion:** In this study, non-invasive respiratory support strategy with late intubation is associated with a shorter length of stay for critically ill patient with COVID-19 compared to an early intubation strategy. A non-invasive strategy would allow a better resource management of the healthcare system during the outbreak. Other studies are warranted to evaluate the impact on the long-term mortality.

**Compliance with ethics regulations:** Yes in clinical research.

FC-266

The effect on proning depends on the interface used: NRB vs HFNC vs NVI

SALLEMI Ilyes¹,², RACHDI Emna¹,², JARRYA Fatma¹,², JAMOUSSI Amira¹,², AYED Samia¹,², BESBES Mohamed¹,², BEN KHELIL Jalila¹,²

¹Hospital Abderrahman Mami, Ariana, Tunisie; ²Faculté de Médecine de Tunis, Tunis, 0

**Correspondence:** Emna RACHDI (e.rachdi@yahoo.fr)

Annals of Intensive Care 2022, **12**(1):FC-266

**Rationale:** Since the PROSEVA study in 2013, prone positioning (PP) is a postural maneuver recommended early in the management of acute respiratory distress syndrome (ARDS) in patients who remain hypoxic on mechanical ventilation. With the increase in the incidence of ARDS over the last 2 years in relation to the COVID-19 pandemic, PP has been attempted in non-intubated patients to improve oxygenation. Several studies have been carried out in non-intubated patients admitted to an intensive care unit for the management of ARDS. We proposed to compare the effect of different oxygenation interfaces during PP wakefulness.

**Patients and methods/Materials and methods:** Between March and May 2021, 117 adult patients were admitted to the medical intensive care unit of MAMI hospital for severe to critical COVID-19. Among them, 56 patients underwent at least one PP session. During the first 24 h, PP sessions of at least 30 min were performed with change of oxygenation interface each time ranging from a non-rebreather mask (NRB) to a high flow nasal canula (HFNC) then to non-invasive ventilation (NIV) last. Blood gas was performed before and 20 min after each session under the same oxygenation parameters. The response to PP was defined by an increase in the PaO₂/FiO₂ ratio of 20%.

**Results:** Fifty-six patients had a PP session. They were male in 56.9% of cases with a mean age of 55 years and mean BMI of 28.06 kg/m². At admission, they had severe ARDS in 46.4% and mild in 42.9%. PP session was performed in conventional oxygen therapy in fifty-one patients. The difference in PaO₂/FiO₂ ratio before and after the session was on average 14 mmHg [− 96, 138 mmHg] with no statistically significant difference (p = 0.09). The response to PP was heterogeneous, with 25.5% (n = 13) responders. Under HFNC, the mean delta PaO₂/FiO₂ was 5.6 mmHg (− 67, 125 mmHg) for all 32 patients, 21 were responders (65%). PP under NIV was tolerated by only 41 patients who had a mean PaO₂/FiO₂ response of 17.6 mmHg (− 120, 197 mmHg) with no statistically significant difference (p = 0.07). Eighteen of them (43.9%) were responders. In contrast to NIV, the PP response under NRB decreased the need for oro-tracheal intubation (p = 0.03). PP significantly improved survival of patients under NRB and HFNC (p = 0.04 for NRB and p = 0.03 for HFNC).

**Conclusion:** Although the benefice of PP in intubated patient is demonstrated, awake PP needs more evidence by conducting more prospective multicentric studies with prolonged proning sessions.

**Compliance with ethics regulations:** Yes in clinical research.

FC-267

Factors associated with mortality in hospitalized Covid-19 patients

ALLOUCHE Hend¹, GUISSOUMA Jihene¹, TRABELSI Insaf¹, BACHA Ichrak¹, SAMET Mohamed¹, BRAHMI Habib¹, GHADHOUNE Hatem¹

¹Hôpital universitaire Habib Bougatfa de Bizerte, Bizerte, Tunisie

**Correspondence:** Hend ALLOUCHE (hend.allouche@fmt.utm.tn)

Annals of Intensive Care 2022, **12**(1):FC-267

**Rationale:** The emergence of the novel Covid-19 has caused millions of deaths worldwide. This study aimed to identify factors that are associated with mortality in hospitalized Covid-19 patients.

**Patients and methods/Materials and methods:** This was a retrospective, observational cohort study conducted on adult patients hospitalized in intensive care unit with confirmed Covid-19 infection, between January 2021 and September 2021. Demographics, clinical pattern, laboratory and radiological investigations associated with increased rate of mortality were analyzed.

**Results:** Of the 140 patients included, mortality rate was 70.3%. Main factors associated with mortality among our cohort were age over 60 years (p < 0.001), history of hypertension (p = 0.001) and chronic kidney failure (p = 0.04). Also, elevated inflammatory markers and severity scores were associated with higher mortality. Patients placed on mechanical ventilation and those who had nosocomial infections had an increased rate of mortality (p < 0.001 and p = 0.01 respectively). Greater lung involvement and obesity were not associated with higher mortality in our study.

**Conclusion:** In our study several factors were associated with mortality as advanced age, hypertension, chronic kidney failure, elevated inflammatory markers and severity scores, mechanical ventilation and nosocomial infections.

**Compliance with ethics regulations:** Yes in clinical research.

FC-268

Is procalcitonin useful to diagnose early bacterial pulmonary co-infection among intubated patients with SARS-CoV-2 or influenza pneumonia?

SAURA Ouriel¹, ROUZÉ Anahita¹, MARTIN-LOECHES Ignacio², POVOA Pedro³, DEMOSTHENES Makris⁴, ARTIGAS Antonio⁵, LABREUCHE Julien¹, NSEIR Saad¹

¹CHU Lille, Lille, France; ²Multidisciplinary Intensive Care Research Organization (MICRO), St James Hospital, Dublin, Irlande; ³Hospital de Sao Francisco Xavier, Lisbon, Portugal; ⁴University Hospital of Larissa, Larissa, Grece; ⁵Corporacion Sanitaria Universitaria Parc Tauli, CIBER Enferme dades Respiratorias, Sabadell, Espagne

**Correspondence:** Ouriel SAURA (ouriel.saura@gmail.com)

Annals of Intensive Care 2022, **12**(1):FC-268

**Rationale:** A large proportion of critically ill patients admitted for severe coronavirus disease 2019 (COVID-19) receive empirical antimicrobial treatment upon admission. Recent studies have reported a low rate (< 10%) of early bacterial co-infection among patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia, and significantly lower compared to patients with influenza pneumonia (1). We aimed to determine the performance of procalcitonin (PCT) to diagnose early bacterial pulmonary co-infection within 48 h after intubation in critically ill patients with SARS-CoV-2 or influenza pneumonia.

**Patients and methods/Materials and methods:** We performed a post hoc analysis of data from the multicenter retrospective coVAPid cohort study. Adult patients receiving invasive mechanical ventilation for at least 48 h for SARS-CoV-2 (first wave in Europe) or influenza pneumonia (2016–2020 admissions), and with at least one PCT measurement within 48 h after intubation were considered for the present analysis. Bacterial pulmonary co-infection was defined by bacterial isolation, within 48 h after intubation, in endotracheal aspirates, bronchoalveolar lavage, or blood cultures, or a positive pneumococcal or legionella urinary antigen test. We assessed the performance of PCT to diagnose co-infection using a receiver operating characteristic (ROC)
curve analysis, and the association of PCT with patient's co-infection status and 28-day mortality after pre-specified adjustment (age, sex, IGS2, and disease group) using a multivariable logistic regression model.

**Results:** 615 patients were included (349 in SARS-CoV-2, and 266 in influenza groups). The area under the ROC curve (AUC) was 0.60 (95%CI 0.48 to 0.71) and 0.66 (95%CI 0.58 to 0.73) for the diagnosis of co-infection in SARS-CoV-2 and influenza groups, respectively. PCT was significantly associated with co-infection in patients with influenza pneumonia (adjusted odds ratio (OR) per log increase in level of PCT 1.29 (95%CI 1.13 to 1.48)), but not in patients with SARS-CoV-2 pneumonia (adjusted OR 1.26 (95%CI 0.98 to 1.61)) (Fig. 1). Conversely, adjusted OR for 28-day mortality per log increase of PCT was 1.03 (95%CI 0.89 to 1.19) and 1.41 (95%CI 1.16 to 1.71) in influenza and SARS-CoV-2 groups respectively, suggesting that PCT was a better indicator of disease severity than co-infection among severe COVID-19 patients.

**Conclusion:** We reported a low diagnostic value of PCT to detect bacterial co-infection within 48 h after intubation in patients with severe SARS-CoV-2 or influenza pneumonia. PCT level was significantly associated with 28-day mortality among severe COVID-19 patients.

**Reference 1:** Rouze A, Martin-Loeches I, Povoa P et al. coVAPid study group. Early bacterial identification among intubated patients with COVID-19 or influenza pneumonia: a European multicenter comparative cohort study. Am J Respir Crit Care Med. 2021 May 26;204(5):546.

**Compliance with ethics regulations:** Yes in clinical research.

<figure><img src="image_114.png" /><figcaption>Figure 1 Unadjusted and Pre-specified Adjusted Odds Ratio of Co-infection and 28-day mortality per log increase in highest level of procalcitonin</figcaption></figure>

FC-269

Retrospective comparison of COVID-19 and seasonal influenza mortality and outcomes in the intensive care units of a French university hospital

DE MARIGNAN Donatien¹, VACHERON Charles-Hervé¹, ADER Florence², LECOCQ Maxime¹, RICHARD Jean Christophe², ARGAUD Laurent³, BOHE Julien¹, PIRIOU Vincent¹, ALLAOUCHICHE Bernard¹, FRIGGERI Arnaud¹, WALLET Florent¹

¹CHU LYON SUD - PIERRE BENITE (RHONE), Pierre Benite, France; ²CHU de la CROIX ROUSSE - LYON, Lyon, France; ³CHU EDOUARD HERRIOT - LYON, Lyon, France

**Correspondence:** Donatien DE MARIGNAN (donatien.de-seisan-de-marignan@chu-lyon.fr)

Annals of Intensive Care 2022, **12**(1):FC-269

**Rationale:** Severe COVID-19 has become a major worldwide health concern since its appearance at the end of 2019 in China. Commonalities have been suggested with seasonal influenza. Our objective was to evaluate the intrinsic mortality and burden of SARS-CoV-2 and seasonal influenza pneumonia in intensive care units (ICU) in a university hospital in a major city in France.

**Patients and methods/Materials and methods:** We conducted a retrospective study in six ICUs in a single institution. Consecutive patients admitted to an ICU with SARS-CoV-2 pneumonia from February 27 to April 4, 2020 (COVID-19 group) and seasonal influenza pneumonia from November 1, 2015 to April 30, 2019 (INFLUENZA group) were screened. A total of 350 patients were included in the COVID-19 group (18 refused to consent) and 325 in the INFLUENZA group (1 refused to consent). Diagnosis was confirmed by RT-PCR. Follow-up was completed on April 1, 2021. We collected demographic characteristics, comorbidities, long-term medications at ICU admission, and evaluated

difference in 90-day adjusted-mortality between the COVID-19 and INFLUENZA group using a multivariable Cox proportional hazards model.

**Results:** COVID-19 patients were younger, mostly men, and had a higher median BMI, and comorbidities, including immunosuppressive condition or respiratory history were less frequent. In univariate analysis, no significant differences were observed between the 2 groups regarding in-ICU mortality, 30, 60 and 90-day mortality. After Cox modelling adjusted on age, sex, BMI, cancer, sepsis-related organ failure assessment (SOFA) score, simplified acute physiology (SAPS II) score, chronic obstructive pulmonary disease and myocardial infarction, the probability of death associated with COVID-19 was significantly higher in comparison to seasonal influenza (HR 1.57, CI95% [1.14; 2.17]; p=0.006). The clinical course and morbidity profile of both groups was markedly different; COVID-19 patients had less severe illness at admission (SAPS II score, 37 [28–48] vs. 48 [39–61], p < 0.001, and SOFA score, 4 [2–8] vs. 8 [5–11], p < 0.001), but the disease was more severe considering ICU length of stay, duration of mechanical ventilation, PEEP level, and prone positioning requirement.

**Conclusion:** After ICU admission, COVID-19 was associated with an increased risk of death compared to seasonal influenza. Patient characteristics, clinical course, and morbidity profile of these diseases is markedly different. Patients with seasonal influenza die because of their comorbidities while COVID-19 patients die because of COVID-19 pneumonia.

**Compliance with ethics regulations:** Yes in clinical research.

FC-270

Covid-19 and pregnancy: what we should know?

SDIRI Ines¹, FITOUHI Nizar¹, DRIDI Amira¹, DORGHAM Sana¹, OUERGHI Sonia¹, MESTIRI Tahar¹

¹hôpital ariana abderahmen memi, Sfax, Tunisie

**Correspondence:** Ines SDIRI (sdiri.ynes@gmail.com)

Annals of Intensive Care 2022, **12**(1):FC-270

**Rationale:** Physiological changes during pregnancy have a significant impact on the immune system, respiratory system, cardiovascular function, and coagulation. The impact of SARS-CoV-2 in pregnancy remains to be determined. Our study aim to describe the characteristics of COVID19 infections in per partum patients before vaccine authorization.

**Patients and methods/Materials and methods:** A retrospective and descriptive study of 9 months duration carried out in the COVID intensive care unit including all per partum patients with COVID 19 pneumonia between March 2021 and September, 2021. All pregnant or immediate postpartum women hospitalized for SARS-CoV2 infection were included. Demographic, clinical, biologic, radiographic, therapeutic and outcomes data were collected. The primary endpoint was maternal mortality. Two groups were identified: Group 1 = Survivors and Group 2 = Deceased. The differences in data of the patients were evaluated.

**Results:** During the study period, we collected 17 patients. The incidence of COVID19 infection in per partum patients was 5% in our series. All patients were admitted postpartum (75% by caesarean section). The median age was 31(25–38) years. The comorbidities were chronic respiratory deficient (3 patients) and hypothyroidism (3). The mean BMI was 28±3 kg/m². All patients were unvaccinated. Seven were multiparous. The mean gestational age was 27±6 weeks of amenorrhea. The mean PaO2/FiO2 ratio at admission was 98±35 mmHg. All patients admitted to the ICU were in respiratory distress. Severe ARDS was observed in 11 patients (64%). 47% patients received high-flow nasal oxygen therapy and one patient was under mechanical ventilation at admission. Chest CT scans were performed in 15 patients (88.2%). An involvement highest of 50% was observed in 13 patients (76.4%). All patients received anticoagulation and corticosteroid therapy. Invasive mechanical ventilation (IMV) was required in 5 cases. 5 patients (29.4%) needed the use of vasoactive amines. The occurrence of nosocomial infection was found in 7 patients, 2 patients were developed acute kidney injury and one required hemodialysis, 6 patients presented a thromboembolic event. Tocilizumab was
prescribed for 2 patients and one patient was discharged for ECMO. The median length of hospitalization was 9±7 days and the mortality rate was 46.3%. Univariate analysis of the 2 groups showed that use of IMV (G1: 5 (100%) vs. G2: 0 (0%); p=0.001) and nosocomial infection (G1: 4 (80%) vs. G2: 0 (0%); p=0.01) were associated with excess mortality.

**Conclusion:** Currently data didn't show significant relationship between COVID-19 severity and pregnancy and there is no strong evidence that covid-19 lead to adverse pregnancy outcome, but further studies are needed.

**Compliance with ethics regulations:** Yes in clinical research.

FC-271

Pregnant women and COVID 19 in intensive care: series of 18
cases

BOUSBIA Soulef¹, DJEBBARI Abdelkader¹, KRABA Rachid¹, BENHAMED Mohamed Amine¹

¹CHU D'ORAN, Oran, Algerie

**Correspondence:** Soulef BOUSBIA (bsoulef90@gmail.com)

*Annals of Intensive Care* 2022, **12**(1):FC-271

**Rationale:** In pregnant women, the symptoms of COVID-19 are similar to those of the general population in most cases. That said, like any population at risk, more serious symptoms may appear such as pneumonia or ARDS. The objective is to define the clinical, biological and therapeutic characteristics as well as the management of a series of pregnant women with COVID-19.

**Patients and methods/Materials and methods:** This is a retrospective and descriptive study which collected 18 pregnant patients affected by the Coronavirus SARS-CoV-2 in the intensive care unit between July 20 and September 15, 2021 We included parturient requiring a high flow of polypneic oxygen at 30 cycles/min with an $SPO_2<92\%$ and the parturient without sign of respiratory distress were excluded.

**Results:** The average age is 31 years old. Six patients were followed for a chronic disease. Gestational diabetes was the most common comorbidity. Contact with a suspected or confirmed case of COVID-19 was identified in 10 patients. The average incubation period for the virus was 6.89 days. The average term of pregnancy was 33.36 weeks of amenorrhea. The preferred way of delivery was caesarean section. The most frequently reported symptoms were fever in all patients, dyspnea in all patients. 16 patients were taken care of in medical intensive care for an array of acute respiratory distress syndrome (ARDS) after cesarean section. Four patients were put on nasal high-flow oxygen therapywith recourse to mechanical ventilation after 48 h. In the 14 other cases, mechanical ventilation was indicated after the caesarean section. Symptomatic treatment and antibiotic therapy had been started upon admission in all the patients. Five patients were intubated 12 days, 5 patients died of massive pulmonary embolism, 5 of the patients died of pulmonary superinfection, 4 patients died of severe hypoxia.

**Conclusion:** This is a global pandemic with high mortality worldwide. Published studies on SARS-COV-19 infection during pregnancy are few; they are no more at risk of being infected with the coronavirus, but the disease can have significant consequences on the course of their pregnancy. They are also more prone to severe forms of Covid-19.

**Compliance with ethics regulations:** N/A.

FC-272

Pregnant women and COVID19: hospitalization in intensive care
unit predictive factors

JAAFAR Nour Zayneb¹, FATHALLAH Ines¹, KOURAICHI Nadia¹

¹Université de Tunis - El Manar, Hôpital régional de Ben Arous, Tunis,
Tunisie

**Correspondence:** Nour Zayneb JAAFAR (jaafar.nour.zayneb@gmail.com)

*Annals of Intensive Care* 2022, **12**(1):FC-272

**Rationale:** Pregnant women, a vulnerable population, have not been spared from the COVID-19 pandemic. In the absence of vaccination,

severe forms and acute respiratory distress syndromes (ARDS) have been reported.

**Patients and methods/Materials and methods:** We reviewed all data of confirmed COVID-19 pregnant patients hospitalized in our Hospital ICU and in gynecology's department between September 2020 and September 2021 for the management of acute pneumopathy due to Sars-Cov-2. Infection was confirmed by RT-PCR, rapid test, or chest CT scan. Epidemiological, clinical, biologic and radiographic data and outcomes were collected.

**Results:** Thirty-six patients were included with a mean age of 33±5 years and a mean term of pregnancy of 34±4 weeks. The median consultation time after the onset of symptoms was 3.5 days [1;7] and the median hospital stay was 4 days [1;7]. Among 36 pregnant women, no one of the patients was vaccinated against SARS-CoV-2. Eleven patients (34%) were hospitalized in the ICU. Symptoms were dominated by respiratory signs, cough and dyspnea, respectively 21 (65%) and 15 (47%) patients. The different ventilatory supports were: single oxygen therapy (50%), high concentration mask (34%), high flow oxygen therapy (12.5%), and invasive ventilation (16%). Predictive factors for hospitalization in ICU were: dyspnea [p<10-3 RR=5.25 95% CI [2.174; 12.679]], oxygen uptake [p=0.01 RR=3.81 95% CI [1.737; 8.393]], delay before consultation >4.5 days [p=0.021 RR=3.897 95% CI [1.267; 11.991]] and a period of hospitalization before admission in ICU >5.5 days [p=0.002 RR=6.33 95% CI [1.608; 24.939]]. Among the six patients who had invasive ventilation, tracheotomy was practiced at three patients (27%). The ICU stay was complicated by septic shock in 4 patients (36%) and a thromboembolic disease in 4 patients (36%). The median length of ICU stay was 11 [5.54] days. The ICU mortality was high around 18% against an overall mortality of 6%.

**Conclusion:** Mortality was significant in our study: 34% of patients required hospitalization in ICU with an overall mortality of 6%.

**Compliance with ethics regulations:** Yes in clinical research.

FC-273

Prevalence and outcome of SARS-COV2 bacterial coinfection

GHABARA Racha¹, AYED Samia¹, DEBBICHE Lilya¹, RACHDI Emna¹, JARR

AYA Fatma¹, JAMOUSSI Amira¹, BEN KHELJAL Ilalı¹

¹HOPITAL ABDERRAHMEN MAMI, Ariana, Tunisie

**Correspondence:** Samia AYED (samia.ayed@yahoo.fr)

*Annals of Intensive Care* 2022, **12**(1):FC-273

**Rationale:** The rate of SARS-CoV2 bacterial coinfection is poorly defined. The decision to administer antibiotics early in the course of SARS-CoV2 infection depends on the likelihood of bacterial coinfection. The purpose of this study was to examine the prevalence of SARS-COV2 bacterial co-infection on admission and to investigate the impact on outcome.

**Patients and methods/Materials and methods:** This was a retrospective study carried within a medical intensive care unit in Abderrahmen Mami Hospital between March 2020 and August 2021. All consecutive patients admitted for severe COVID-19 were enrolled. Bacterial coinfection was systematically investigated on intensive care unit (ICU) admission. A comparative study was conducted between the coinfection group and a matched non-coinfection group based on age, body mass index, severity scores and PaO2/FiO2 ratio on admission.

**Results:** During the study period, 544 patients were hospitalized in the intensive care unit for severe COVID-19. Fifty-four per cent of patients received antibiotics before ICU admission (n=292) including amoxicillin-clavulanic acid association (n=85), azithromycine (n=129) and levofloxacine (n=29). Only 49 patients showed bacterial coinfection on admission (9%). Most involved pathogens were: enterobacteriaceae (Klebsiella n=15, Enterobacter cloacae n=2, Serratia marcescens n=2), Staphylococcus aureus methicilline sensitive (n=5) and non-fermentative Gram-negative bacilli such as Pseudomonas aeruginosa (n=6). Twenty-one patients with bacterial coinfection received antibiotics prior to the ICU admission (43%). No statistical difference was found in the univariate analysis comparing the coinfection group and the matched non-coinfection group. Only SGOT and SGPT levels were significatively higher in the coinfection group (p=0,05 and
p = 0,03 respectively). Need for mechanical ventilation and mortality did not differ significantly between the two groups (p = 0,371 and p = 0,469 respectively).

**Conclusion:** Bacterial coinfection rate in patients admitted with severe SARS-CoV2 infection is low. No significative difference was found between coinfected and non-coinfected group. These findings support unrecommended systematic antibiotics association to treat severe viral infection.

**Compliance with ethics regulations:** Yes in clinical research.

**Supplementary Information**

The online version contains supplementary material available at https://doi.org/10.1186/s13613-022-01016-6.

**Additional file 1.** Disclosures of links of interest.

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