Use of almitrine in spontaneously breathing patients with COVID-19 treated with high-flow nasal cannula oxygen therapy and with persistent hypoxemia.

BACKGROUND: Almitrine, a selective pulmonary vasoconstrictor in hypoxic area, improves oxygenation in mechanically ventilated patients with COVID-19 but its effects in spontaneously breathing patients with COVID-19 remain to be determined. METHODS: We prospectively studied the effects of almitrine (16 µg/kg/min over 30 min followed by continuous administration in responders only) in 62 patients (66% of male, 63 [53-69] years old) with COVID-19 treated with high-flow nasal cannula oxygen therapy (HFNO) and with persistent hypoxemia, defined as a PaO2/FiO2 ratio < 100 with FiO2 > 80% after a single awake prone positioning session. Patients with an increase in PaO2/FiO2 ratio > 20% were considered as responders. RESULTS: Overall, almitrine increased the PaO2/FiO2 ratio by 50% (p < 0.01), decreased the partial arterial pressure of carbon dioxide by 7% (p = 0.01) whereas the respiratory rate remained unchanged and 46 (74%) patients were responders. No patient experienced right ventricular dysfunction or acute cor pulmonale. The proportion of responders was similar regardless of the CT-Scan radiological pattern: 71% for the pattern with predominant ground-glass opacities and 76% for the pattern with predominant consolidations (p = 0.65). Responders had lower intubation rate (33 vs. 88%, p < 0.01), higher ventilator-free days at 28-day (28 [20-28 ] vs. 19 [2-24] days, p < 0.01) and shorter ICU length of stay (5 [3-10] vs.12 [7-30] days, p < 0.01) than non-responders. CONCLUSIONS: Almitrine could be an interesting therapy in spontaneously breathing patients with COVID-19 treated with HFNO and with persistent hypoxemia, given its effects on oxygenation without serious adverse effects regardless of the CT-Scan pattern, and potentially on intubation rate. These preliminary results need to be confirmed by further randomized studies.

Use of high-flow nasal cannula oxygen and risk factors for high-flow nasal cannula oxygen failure in critically-ill patients with COVID-19.

BACKGROUND: High-flow nasal oxygen therapy (HFNC) may be an attractive first-line ventilatory support in COVID-19 patients. However, HNFC use for the management of COVID-19 patients and risk factors for HFNC failure remain to be determined. METHODS: In this retrospective study, we included all consecutive COVID-19 patients admitted to our intensive care unit (ICU) in the first (Mars-May 2020) and second (August 2020- February 202) French pandemic waves. Patients with limitations for intubation were excluded. HFNC failure was defined as the need for intubation after ICU admission. The impact of HFNC use was analyzed in the whole cohort and after constructing a propensity score. Risk factors for HNFC failure were identified through a landmark time-dependent cause-specific Cox model. The ability of the 6-h ROX index to detect HFNC failure was assessed by generating receiver operating characteristic (ROC) curve. RESULTS: 200 patients were included: HFNC was used in 114(57%) patients, non-invasive ventilation in 25(12%) patients and 145(72%) patients were intubated with a median delay of 0 (0-2) days after ICU admission. Overall, 78(68%) patients had HFNC failure. Patients with HFNC failure had a higher ICU mortality rate (34 vs. 11%, p = 0.02) than those without. At landmark time of 48 and 72 h, SAPS-2 score, extent of CT-Scan abnormalities > 75% and HFNC duration (cause specific hazard ratio (CSH) = 0.11, 95% CI (0.04-0.28), per + 1 day, p < 0.001 at 48 h and CSH = 0.06, 95% CI (0.02-0.23), per + 1 day, p < 0.001 at 72 h) were associated with HFNC failure. The 6-h ROX index was lower in patients with HFNC failure but could not reliably predicted HFNC failure with an area under ROC curve of 0.65 (95% CI(0.52-0.78), p = 0.02). In the matched cohort, HFNC use was associated with a lower risk of intubation (CSH = 0.32, 95% CI (0.19-0.57), p < 0.001). CONCLUSIONS: In critically-ill COVID-19 patients, while HFNC use as first-line ventilatory support was associated with a lower risk of intubation, more than half of patients had HFNC failure. Risk factors for HFNC failure were SAPS-2 score and extent of CT-Scan abnormalities > 75%. The risk of HFNC failure could not be predicted by the 6-h ROX index but decreased after a 48-h HFNC duration.

Current Advances in Lung Ultrasound in COVID-19 Critically Ill Patients: A Narrative Review.

Lung ultrasound (LUS) has a relatively recent democratization due to the better availability and training of physicians, especially in intensive care units. LUS is a relatively cheap and easy-to-learn and -use bedside technique that evaluates pulmonary morphology when using simple algorithms. During the global COVID-19 pandemic, LUS was found to be an accurate tool to quickly diagnose, triage and monitor patients with COVID-19 pneumonia. This paper aims to provide a comprehensive review of LUS use during the COVID-19 pandemic. The first section of our work defines the technique, the practical approach and the semeiotic signs of LUS examination. The second section exposed the COVID-19 pattern in LUS examination and the difference between the differential diagnosis patterns and the well-correlation found with computer tomography scan findings. In the third section, we described the utility of LUS in the management of COVID-19 patients, allowing an early diagnosis and triage in the emergency department, as the monitoring of pneumonia course (pneumonia progression, alveolar recruitment, mechanical ventilation weaning) and detection of secondary complications (pneumothorax, superinfection). Moreover, we describe the usefulness of LUS as a marker of the prognosis of COVID-19 pneumonia in the fourth section. Finally, the 5th part is focused on describing the interest of the LUS, as a non-ionized technique, in the management of pregnant COVID-19 women.

Management and outcomes of pregnant women admitted to intensive care unit for severe pneumonia related to SARS-CoV-2 infection: the multicenter and international COVIDPREG study.

PURPOSE: Management and outcomes of pregnant women with coronavirus disease 2019 (COVID-19) admitted to intensive care unit (ICU) remain to be investigated. METHODS: A retrospective multicenter study conducted in 32 ICUs in France, Belgium and Switzerland. Maternal management as well as maternal and neonatal outcomes were reported. RESULTS: Among the 187 pregnant women with COVID-19 (33 ± 6 years old and 28 ± 7 weeks' gestation), 76 (41%) were obese, 12 (6%) had diabetes mellitus and 66 (35%) had pregnancy-related complications. Standard oxygenation, high-flow nasal oxygen therapy (HFNO) and non-invasive ventilation (NIV) were used as the only oxygenation technique in 41 (22%), 55 (29%) and 18 (10%) patients, respectively, and 73 (39%) were intubated. Overall, 72 (39%) patients required several oxygenation techniques and 15 (8%) required venovenous extracorporeal membrane oxygenation. Corticosteroids and tocilizumab were administered in 157 (84%) and 25 (13%) patients, respectively. Awake prone positioning or prone positioning was performed in 49 (26%) patients. In multivariate analysis, risk factors for intubation were obesity (cause-specific hazard ratio (CSH) 2.00, 95% CI (1.05-3.80), p = 0.03), term of pregnancy (CSH 1.07, 95% CI (1.02-1.10), per + 1 week gestation, p = 0.01), extent of computed tomography (CT) scan abnormalities > 50% (CSH 2.69, 95% CI (1.30-5.60), p < 0.01) and NIV use (CSH 2.06, 95% CI (1.09-3.90), p = 0.03). Delivery was required during ICU stay in 70 (37%) patients, mainly due to maternal respiratory worsening, and improved the driving pressure and oxygenation. Maternal and fetal/neonatal mortality rates were 1% and 4%, respectively. The rate of maternal and/or neonatal complications increased with the invasiveness of maternal respiratory support. CONCLUSION: In ICU, corticosteroids, tocilizumab and prone positioning were used in few pregnant women with COVID-19. Over a third of patients were intubated and delivery improved the driving pressure.

Effects of Prone Positioning on Respiratory Mechanics and Oxygenation in Critically Ill Patients With COVID-19 Requiring Venovenous Extracorporeal Membrane Oxygenation.

BACKGROUND: The effect of prone positioning (PP) on respiratory mechanics remains uncertain in patients with severe acute respiratory distress syndrome (ARDS) requiring venovenous extracorporeal membrane oxygenation (VV-ECMO). METHODS: We prospectively analyzed the effects of PP on respiratory mechanics from continuous data with over a thousand time points during 16-h PP sessions in patients with COVID-19 and ARDS under VV-ECMO conditions. The evolution of respiratory mechanical and oxygenation parameters during the PP sessions was evaluated by dividing each PP session into four time quartiles: first quartile: 0-4 h, second quartile: 4-8 h, third quartile: 8-12 h, and fourth quartile: 12-16 h. RESULTS: Overall, 38 PP sessions were performed in 10 patients, with 3 [2-5] PP sessions per patient. Seven (70%) patients were responders to at least one PP session. PP significantly increased the PaO2/FiO2 ratio by 14 ± 21% and compliance by 8 ± 15%, and significantly decreased the oxygenation index by 13 ± 18% and driving pressure by 8 ± 12%. The effects of PP on respiratory mechanics but not on oxygenation persisted after supine repositioning. PP-induced changes in different respiratory mechanical parameters and oxygenation started as early as the first-time quartile, without any difference in PP-induced changes among the different time quartiles. PP-induced changes in driving pressure (-14 ± 14 vs. -6 ± 10%, p = 0.04) and mechanical power (-11 ± 13 vs. -0.1 ± 12%, p = 0.02) were significantly higher in responders (increase in PaO2/FiO2 ratio > 20%) than in non-responder patients. CONCLUSIONS: In patients with COVID-19 and severe ARDS, PP under VV-ECMO conditions improved the respiratory mechanical and oxygenation parameters, and the effects of PP on respiratory mechanics persisted after supine repositioning.

Effect of prone positioning on survival in adult patients receiving venovenous extracorporeal membrane oxygenation for acute respiratory distress syndrome: a systematic review and meta-analysis.

PURPOSE: Previous studies support the potential efficacy of venovenous extracorporeal membrane oxygenation (vvECMO) for improving survival in severe acute respiratory distress syndrome (ARDS) cases. Prone positioning (PP) has been shown to improve the outcomes of moderate-to-severe ARDS patients. Few studies and no randomized controlled trials have evaluated the effect of PP performed in ECMO patients. METHODS: We performed a systematic review and meta-analysis examining the effect of prone positioning for ARDS patients receiving vvECMO on survival. All authors were contacted to obtain complementary information not mentioned in the original articles. The main objective was to compare 28-day survival in vvECMO patients with PP to vvECMO patients without PP (controls). RESULTS: Thirteen studies with a combined population of 1836 patients satisfied the inclusion criteria. PP was associated with a significant improvement in 28-day survival (503 survivors among 681 patients in the PP group [74%; 95% CI 71-77] vs. 450 survivors among 770 patients in the control group [58%, 95% CI 55-62]; RR 1.31 [95% CI 1.21-1.41]; I2 22% [95% CI 0-62%]; P < 0.0001). Survival was also improved in terms of other endpoints (60-day survival, 90-day survival, ICU survival, and hospital survival). In contrast, the duration of mechanical ventilation was increased in vvECMO patients with PP (mean difference 11.4 days [95% CI 9.2-13.5]; 0.64 [95% CI 0.50-0.78]; I2 8%; P < 0.0001). CONCLUSION: According to this meta-analysis, survival was improved when prone positioning was used in ARDS patients receiving vvECMO. The impact of this combination on survival should be investigated in prospective randomized controlled trials.

Impact of Isolation Time of COVID-19 Patients in Intensive Care Unit on Healthcare Workers Contamination and Nursing Care Intensity.

Background: The optimal isolation time of COVID-19 patients in intensive care unit (ICU) is debated. We investigated the impact of two different COVID-19 patient isolation time strategies on healthcare workers (HCW) contamination, intensity of nursing care and potential associated adverse events. Methods: We prospectively included all consecutive COVID-19 patients and HCW in our ICU in the first two pandemic waves (March to May 2020 and August to November 2020). Specific isolation measures for COVID-19 patients were released after two negative RT-PCR assays in the first wave and 14 days after the onset of symptoms in the second wave. Contamination of HCW was assessed at the end of each pandemic wave by combining both a RT-PCR assay and a serological test. Results: Overall, 117 COVID-19 patients and 73 HCW were included. Despite an earlier release from isolation after ICU admission in the second than in the first wave [6 (4-8) vs. 15 (11-19) days, p < 0.01], the proportion of HCW with a positive serological test (16 vs. 17%, p = 0.94) or with a positive RT-PCR assay (3 vs. 5%, p = 0.58) was not different between the two waves. Although a lower nurse-to-bed ratio, the intensity of nursing care was higher in the second than in the first wave. A longer isolation time was associated with accidental extubation (OR = 1.18, 95%CI:1.07-1.35, p = 0.005) but neither with ventilator-associated pneumonia nor with dysglycemia. Conclusion: A shorter isolation time of COVID-19 patients in ICU was not associated with higher HCW contamination, while a longer isolation time seemed to be associated with higher accidental extubation.

Impact of COVID-19 on the association between pulse oximetry and arterial oxygenation in patients with acute respiratory distress syndrome.

Managing patients with acute respiratory distress syndrome (ARDS) requires frequent changes in mechanical ventilator respiratory settings to optimize arterial oxygenation assessed by arterial oxygen partial pressure (PaO2) and saturation (SaO2). Pulse oxymetry (SpO2) has been suggested as a non-invasive surrogate for arterial oxygenation however its accuracy in COVID-19 patients is unknown. In this study, we aimed to investigate the influence of COVID-19 status on the association between SpO2 and arterial oxygenation. We prospectively included patients with ARDS and compared COVID-19 to non-COVID-19 patients, regarding SpO2 and concomitant arterial oxygenation (SaO2 and PaO2) measurements, and their association. Bias was defined as mean difference between SpO2 and SaO2 measurements. Occult hypoxemia was defined as a SpO2 ≥ 92% while concomitant SaO2 < 88%. Multiple linear regression models were built to account for confounders. We also assessed concordance between positive end-expiratory pressure (PEEP) trial-induced changes in SpO2 and in arterial oxygenation. We included 55 patients, among them 26 (47%) with COVID-19. Overall, SpO2 and SaO2 measurements were correlated (r = 0.70; p < 0.0001), however less so in COVID-19 than in non-COVID-19 patients (r = 0.55, p < 0.0001 vs. r = 0.84, p < 0.0001, p = 0.002 for intergroup comparison). Bias was + 1.1%, greater in COVID-19 than in non-COVID-19 patients (2.0 vs. 0.3%; p = 0.02). In multivariate analysis, bias was associated with COVID-19 status (unstandardized ß = 1.77, 95%CI = 0.38-3.15, p = 0.01), ethnic group and ARDS severity. Occult hypoxemia occurred in 5.5% of measurements (7.7% in COVID-19 patients vs. 3.4% in non-COVID-19 patients, p = 0.42). Concordance rate between PEEP trial-induced changes in SpO2 and SaO2 was 84%, however less so in COVID-19 than in non-COVID-19 patients (69% vs. 97%, respectively). Similar results were observed for PaO2 regarding correlations, bias, and concordance with SpO2 changes. In patients with ARDS, SpO2 was associated with arterial oxygenation, but COVID-19 status significantly altered this association.

Case Report: Takotsubo Syndrome Associated With Novel Coronavirus Disease 2019.

Background: Takotsubo cardiomyopathy is triggered by emotional or physical stress. It is defined as a reversible myocardial dysfunction, usually with apical ballooning aspect due to apical akinesia associated with hyperkinetic basal left ventricular contraction. Described in cases of viral infections such as influenza, only few have been reported associated with novel coronavirus disease 2019 (COVID-19) in the recent pandemic. Case summary: A 79-years-old man, with cardiovascular risk factors (type 2 diabetes and hypertension) and chronic kidney disease, presented to the emergency room for severe dyspnea after 8 days of presenting respiratory symptoms and fever. Baseline electrocardiogram (ECG) was normal, but he presented marked inflammatory syndrome. He was transferred to an intensive care unit to receive mechanical ventilation within 6 h, due to acute respiratory distress syndrome. He presented circulatory failure 2 days after, requiring norepinephrine support (up to up to 1.04 µg/kg/min). Troponin T was elevated (637 ng/l). ECG showed diffuse T wave inversion. Echocardiography showed reduced left ventricular ejection fraction (LVEF 40%), with visual signs of Takotsubo cardiomyopathy. Cardiac failure resolved after 24 h with troponin T decrease (433 ng/l) and restoration of cardiac function (LVEF 60% with regression of Takotsubo features). Patient died after 15 days of ICU admission, due to septic shock from ventilator-acquired pneumonia. Cardiac function was then normal. Conclusion: Mechanisms of Takotsubo cardiomyopathy in viral infections include catecholamine-induced myocardial toxicity and inflammation related to sepsis. Differential diagnoses include myocarditis and myocardial infarction. Evidence of the benefit of immunomodulatory drugs and dexamethasone are growing to support this hypothesis in COVID-19.

Use of Venovenous Extracorporeal Membrane Oxygenation in Critically-Ill Patients With COVID-19.

Acute respiratory distress syndrome (ARDS) related to Coronavirus disease (COVID-19) is associated with high mortality. It has been suggested that venovenous extracorporeal membrane oxygenation (ECMO) was suitable in this indication, albeit the effects of ECMO on the mechanical respiratory parameters have been scarcely described. In this case-series, we prospectively described the use of venovenous ECMO and its effects on mechanical respiratory parameters in eleven COVID-19 patients with severe ARDS. Implantation of ECMO occurred 6 [3-11] days after the onset of mechanical ventilation. At the time of ECMO implantation, all patients received neuromuscular blocking agents, three (27%) received inhaled nitric oxide and prone positioning was performed in all patients with 4 [3-5] sessions of PP per patient. Under ECMO, the tidal volume was significantly decreased from 6.1 [4.0-6.3] to 3.4 [2.5-3.6] mL/kg of predicted body weight and the positive end-expiratory pressure level was increased by 25 ± 27% whereas the driving pressure and the mechanical power decreased by 33 ± 25% and 71 ± 27%, respectively. The PaO2/FiO2 ratio significantly increased from 68 [58-89] to 168 [137-218] and the oxygenation index significantly decreased from 28 [26-35] to 13 [10-15]. The duration of ECMO was 12 [8-25] days. Nine (82%) patients experienced ECMO-related complications and the main complication was major bleeding requiring blood transfusions. Intensive care unit mortality rate was 55% but no patient died from ECMO-related complications. In COVID-19 patients with severe ARDS, venovenous ECMO allowed ultra-protective ventilation, improved oxygenation and should be considered in highly selected patients with the most severe ARDS.

Characteristics of Cardiac Injury in Critically Ill Patients With Coronavirus Disease 2019.

BACKGROUND: Cardiac injury has been reported in up to 30% of coronavirus disease 2019 (COVID-19) patients. However, cardiac injury is defined mainly by troponin elevation without description of associated structural abnormalities and its time course has not been studied. RESEARCH QUESTION: What are the ECG and echocardiographic abnormalities as well as their time course in critically ill COVID-19 patients? STUDY DESIGN AND METHODS: The cardiac function of 43 consecutive COVID-19 patients admitted to two ICUs was assessed prospectively and repeatedly, combining ECG, cardiac biomarker, and transthoracic echocardiographic analyses from ICU admission to ICU discharge or death or to a maximum follow-up of 14 days. Cardiac injury was defined by troponin elevation and newly diagnosed ECG or echocardiographic abnormalities, or both. RESULTS: At baseline, 49% of patients demonstrated a cardiac injury, and 70% of patients experienced cardiac injury within the first 14 days of ICU stay, with a median time of occurrence of 3 days (range, 0-7 days). The most frequent abnormalities were ECG or echocardiographic signs, or both, of left ventricular (LV) abnormalities (87% of patients with cardiac injury), right ventricular (RV) systolic dysfunction (47%), pericardial effusion (43%), new-onset atrial arrhythmias (33%), LV relaxation impairment (33%), and LV systolic dysfunction (13%). Between baseline and day 14, the incidence of pericardial effusion and of new-onset atrial arrhythmias increased and the incidence of ECG or echocardiographic signs, or both, of LV abnormalities as well as the incidence of LV relaxation impairment remained stable, whereas the incidence of RV and LV systolic dysfunction decreased. INTERPRETATION: Cardiac injury is common and early in critically ill COVID-19 patients. ECG or echocardiographic signs, or both, of LV abnormalities were the most frequent abnormalities, and patients with cardiac injury experienced more RV than LV systolic dysfunction.