Noninvasive Support Research Articles

Acute Respiratory Failure and Mechanical Ventilation in Women With COVID-19 During Pregnancy: Best Clinical Practices.

Symptomatic pregnant women with coronavirus disease-2019 (COVID-19) are at increased risk of severe disease and death compared with symptomatic nonpregnant females of reproductive age. Among those who become critically ill, profound acute hypoxemic respiratory failure is the dominant finding. Significant morbidity and mortality from COVID-19 are largely due to acute viral pneumonia that evolves to acute respiratory distress syndrome. Admission of these patients with critical disease to an intensive care unit and initiation of invasive mechanical ventilation may be indicated. Effective ventilatory support can be challenging in the COVID-19 patient population, even more so when the need occurs in a woman during pregnancy. Key respiratory changes during pregnancy are reviewed. Principles related to maternal-fetal oxygen transport, assessment of ventilation and oxygenation status, and oxygenation goals are also reviewed. Selected concepts related to mechanical ventilatory support for the woman with COVID-19 and acute respiratory failure during pregnancy are presented including indications for ventilatory support, noninvasive support, and invasive ventilator management. Challenges in providing care to this patient population are identified as well as strategies to address them going forward.

Maternal Mortality with SARS-COV-2 during its 4th Wave in Pakistan: The Vaccine Paradox and Pregnancy.

The goal of this study was to investigate the maternal death rate among admitted pregnant patients with SARS-COV-2 during its 4th wave in Pakistan. It was a cross-sectional analytical study, carried on pregnant patients admitted due to COVID-19, in Sadiq Abbasi Hospital from 15th August to 15th September, 2021. Thirty-three PCR confirmed and HRCT suggestive patients were included with mean age of 28 ± 4.5 years and mean gestational age of 28.5 ± 6 weeks. Twenty-seven (81%) were non-vaccinated, 22 (66%) were admitted with severe disease, 13 (39.4%) and 11 (33.3%) were on non-invasive and invasive ventilator support, respectively. Only nine (27%) patients could continue their pregnancy. Fifteen (45%) patients had severe oligohydramnios. Twenty-two (66.7%) patients were died, all were unvaccinated. Regression analysis for maternal mortality predicted by severity and vaccination status was significant with R2=.68, F (1, 31) =66.6, p <.001 CI (-.69, -.42) and R2=.44, F (1, 31) = 24.8, p <.001 CI (-1.14, -.48), respectively. There was substantial mortality in the admitted and non-vaccinated pregnant patients with COVID-19. Key Words: Pregnancy, Vaccination, Severe COVID, Maternal outcome.

Modified Visual Geometric Group Architecture for MRI Brain Image Classification

The advancement of automated medical diagnosis in biomedical engineering has become an important area of research. Image classification is one of the diagnostic approaches that do not require segmentation which can draw quicker inferences. The proposed non-invasive diagnostic support system in this study is considered as an image classification system where the given brain image is classified as normal or abnormal. The ability of deep learning allows a single model for feature extraction as well as classification whereas the rational models require separate models. One of the best models for image localization and classification is the Visual Geometric Group (VGG) model. In this study, an efficient modified VGG architecture for brain image classification is developed using transfer learning. The pooling layer is modified to enhance the classification capability of VGG architecture. Results show that the modified VGG architecture outperforms the conventional VGG architecture with a 5% improvement in classification accuracy using 16 layers on MRI images of the REpository of Molecular BRAin Neoplasia DaTa (REMBRANDT) database.

Profile and outcome of COVID-19 patients treated at a secondary hospital in Central India during the second wave of the pandemic.

The second wave of the coronavirus disease 2019 (COVID-19) pandemic resulted in a significant rise in the number of infections and deaths as compared to the first wave. The published literature till now is limited to tertiary hospitals. We did this study to describe the demographic characteristics and outcomes of patients admitted to a secondary care hospital in central India during the second wave of the pandemic. This was a single-center, retrospective observational study conducted in a secondary hospital in central India. The data of patients with COVID-19 infection admitted between March 25 to May 25, 2021, were retrieved and analyzed. A total of 184 patients were included in the study. The mean age was 54.8 ± 14.5 years. Comorbidities included hypertension (40.2%), diabetes mellitus (29.9%), hypothyroidism (4.3%), and asthma (2.7%). The most common presenting complaints were cough (78.8%), breathlessness (61.4%), and fever (60.9%). The mean duration of symptoms was 5.4 ± 2.6 days. According to High-Resolution Computerised Tomography (HRCT) chest severity score, 29/181 (16%) patients had mild disease, 135/181 (74.5%) patients had moderate disease, and 17/181 (9.5%) patients had severe disease. The majority of the patients received remdesivir (90.2%) and 123 patients (66.8%) received corticosteroids. Half the patients (52.2%; n = 96) required intensive care unit admission, 79.3% (145 patients) required oxygen support, and 8.1% (15 patients) required non-invasive ventilator support. Our study from a secondary hospital setup showed that the second wave was very severe with a high requirement of oxygen support and intensive care monitoring.

Survival Benefit of High Dose Versus Usual Dose of Baricitinib in Hospitalized Patients with COVID-19: A Systematic Review

Baricitinib is an oral selective Janus kinase 1 and 2 inhibitor with known anti-inflammatory and anti-viral properties. In patients hospitalized for coronavirus disease 2019 (COVID-19), baricitinib has shown to reduce the risk of death in line with dexamethasone and tocilizumab. However, the most effective and safe dose or optimal dose of baricitinib in severe COVID-19 was not addressed. We conducted this systematic review to assess whether higher than usual dose could further improve survival as primary outcome. The need of ICU (Intensive care Unit) and Invasive or non-invasive positive pressure ventilation, time to wean from oxygen, length of stay at hospital and adverse events were analyzed as secondary outcome. We included 10,032 patients in 5 studies (2 randomised control trials and 3 high quality clinical trials). Among them,5,071 patients received baricitinib at different dosage (4909 patients received 4 mg once daily and 162 patients got more than 4 mg daily) and 4961 received standard of care. Baseline characteristics including mean age, sex, co-morbidities, inflammatory marker (C-reactive protein/CRP) were similar across the intervention and standard care groups. 4 out of 5 trials showed significant survival benefit in baricitinib group usual to higher dose (4 to 8 mg daily). Use of higher dose in 3 controlled trials was associated with significant reduction in admission to ICU and requirement of invasive or non-invasive ventilation support, shortening of hospital stay and earlier stabilization of oxygen status which was not evident in two randomized control trials using usual dose (4 mg daily). There was no significant difference in any serious adverse events or opportunistic infections between higher dose versus usual dose group. Therefore, baricitinib in higher dose could be a potent, highly effective and safe immunomodulatory drug in hospitalized patients with severe COVID-19.

Pulmonary and central nervous system aspergillosis in a patient with COVID-19 infection

Introduction. Patients with COVID-19 infection are vulnerable to a variety of serious complications, including invasive fungal infections such as aspergillosis. Because pulmonary aspergillosis is difficult to confirm with perfect confidence, it has been classified as ?proven,??probable,? and ?possible.? We present a patient with COVID-19 infection in whom a ?probable? pulmonary aspergillosis was complicated by hematogenous spread into brain with formation of multiple abscesses. Case outline. A 67-year-old female was diagnosed with COVID-19 infection using polymerase chain reaction (PCR) from a nasopharyngeal swab. The patient had never been vaccinated before. Despite standard therapy and noninvasive oxygen support, the patient?s health deteriorated one month following the onset of the disease, with chest discomfort, cough, and hemoptysis. Thoracic computed tomography (CT) revealed bilateral infiltrative lesions with varying diameters of cavities, primarily in the left lung, as well as modest effusions in both pleural spaces. Aspergillus hyphae were isolated from tracheobronchial aspirates. Despite therapy with Amphotericin B, which was only available antifungal medication at the time, the patient fell into a coma. A CT scan of the skull revealed several infiltrative lesions inside the brain, some with cavities suggestive to metastatic abscesses, most likely of fungal etiology (Aspergillus) as a result of hematogenous spread of pulmonary aspergillosis. Despite therapy and all other precautions, the patient died. The autopsy was not carried out. Conclusion. In addition to other complications, COVID-19 patients may develop pulmonary aspergillosis, which can be fatal because of the possibility of hematogenous spread to the brain.

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Spontaneous alveolo-pleural fistula in a case of COVID-19 pneumonia-challenges and solutions: case report

COVID-19 pneumonia has demonstrated a wide spectrum of clinical presentations that have yet to be completely uncovered. As this pandemic progresses, uncommon presentations of this disease have come into light. Development of broncho/alveolo-pleural fistula in a patient with COVID-19 pneumonia is a rare phenomenon with only 4 cases reported in literature till date. A 61-year-old gentleman presented to the emergency department with fever, cough, and shortness of breath. His initial chest X-ray was suggestive of a viral pneumonia that was later confirmed to be due to COVID-19. The patient was put on non-invasive ventilator support and treated with empirical antibiotics, glucocorticoids, anti-viral medications and convalescent plasma therapy. Four weeks into the patient’s hospital course, his vital parameters suddenly deteriorated with a subsequent chest X-ray showing a tension pneumothorax, for which a chest tube insertion was done. However, when the air leak did not resolve by the 3rd day, a chest computed tomography (CT) was planned which showed a spontaneous alveolo-pleural fistula (APF). The patient was managed with conservative treatment using negative suction applied to an underwater seal, had his chest tube removed 10 days later and was discharged subsequently. Spontaneous fistulisation between broncho-alveolar tree and pleura can occur rarely in patients with COVID-19 pneumonia and can be managed using underwater seal with negative suction, insertion of endobronchial valves or surgical closure, and needs to be individualised.

Hyperoxemia among Pediatric Intensive Care Unit Patients Receiving Oxygen Therapy.

Supratherapeutic oxygen levels consistently cause oxygen toxicity in the lungs and other organs. The prevalence and severity of hyperoxemia among pediatric intensive care unit (PICU) patients remain unknown. This was the first study to examine the prevalence and duration of hyperoxemia in PICU patients receiving oxygen therapy. This is a retrospective chart review. This was performed in a setting of 36-bed PICU in a quaternary-care children's hospital. All the patients were children aged <18 years, admitted to the PICU for ≥24 hours, receiving oxygen therapy for ≥12 hours who had at least one arterial blood gas during this time. There was no intervention. Of 5,251 patients admitted to the PICU, 614 were included in the study. On average, these patients received oxygen therapy for 91% of their time in the PICU and remained hyperoxemic, as measured by pulse oximetry, for 65% of their time on oxygen therapy. Patients on oxygen therapy remained hyperoxemic for a median of 38 hours per patient and only 1.1% of patients did not experience any hyperoxemia. Most of the time (87.5%) patients received oxygen therapy through a fraction of inspired oxygen (FiO 2 )-adjustable device. Mean FiO 2 on noninvasive support was 0.56 and on invasive support was 0.37. Mean partial pressure of oxygen (PaO 2 ) on oxygen therapy was 108.7 torr and 3,037 (42.1%) of PaO 2 measurements were >100 torr. Despite relatively low FiO 2 , PICU patients receiving oxygen therapy are commonly exposed to prolonged hyperoxemia, which may contribute to ongoing organ injury.

Update on ventilation management in the Pediatric Intensive Care Unit.

Studies have shown that up to 63% of pediatric intensive care unit patients admitted with acute respiratory or cardiorespiratory illness require mechanical ventilation. Mechanical ventilator support can be divided into three phases: initiation, escalation, and resolution. Noninvasive ventilation is typical during the initiation phase in the management of acute pediatric respiratory failure. The major advancements in the use of noninvasive ventilation involve the emergence of high-flow nasal cannula and how widespread the use of high-flow nasal cannula has become in pediatric critical care practice. When high-flow nasal cannula fails, escalation to continuous positive airway pressure or bi-level positive airway pressure is the next step in respiratory care progression. Careful clinical assessment is necessary to avoid delayed escalation between forms of noninvasive support or escalation to intubation and invasive mechanical ventilation. Advancements in conventional mechanical ventilation are centered on optimizing ventilator settings and customizing monitoring with the overarching goal to reduce complications of mechanical ventilation, such as ventilator-induced lung injury. New mechanical ventilator strategies integrating esophageal pressure monitoring, volumetric capnography, and neurally adjusted ventilator assist help to optimize conventional ventilator support. Nonconventional modes of ventilation in the intensive care unit are high-frequency modes and airway pressure release ventilation. Extracorporeal pulmonary support via extracorporeal membrane oxygenation or paracorporeal lung assist devices provides rescue options when conventional and nonconventional methods fail. During resolution of a course of mechanical ventilator support, reliable weaning strategies and extubation readiness testing are lacking in pediatric critical care. Further, timing of tracheostomy, risk reduction in ventilator-induced lung injury, and decreased sedation requirements in pediatric patients requiring mechanical ventilation in the pediatric intensive care unit are areas of ongoing research.

A STUDY OF CLINICAL PROFILE OF PEDIATRIC COVID 19 PATIENTS IN A GOVERNMENT TERTIARY CARE HOSPITAL IN INDIA

BACKGROUND AND OBJECTIVES:After two stormy waves in adults, epidemiologists are predicting third wave to be more severe in vulnerable pediatric population which is yet to be vaccinated. Therefore, to address this issue we aim to present clinical characteristics and outcome of children with COVID-19 infection admitted to a government tertiary care hospital during rst and second COVID-19 pandemic wave which can help in planning clinical services to manage these children in face of escalating pandemic. METHOD: This was a cross-sectional observational study of 94 children admitted with COVID-19 infection between April 2020 and March 2021 who were tested positive by RTPCR or Rapid antigen test for COVID-19. RESULTS: In the study population of 94 children, the Median age was 4 years with Age group ranging from 3 days -12 years consisting of 28.7% infants. 53.2% were males and 81.9% had history of exposure in family. Out of total admissions, 25(26.6%) were asymptomatic, 48 (51.1%) had mild symptoms, 7.4% had moderate illness and 14.9% were severely ill. Fever (54.3%), cough 26.6%, and cold 21.3% were the most common presenting complaints. 22(23.4%) had co morbidities with SAM being most common. Amongst the inammatory markers, it was noticed that, 27(28.7%) had raised CRP levels, 36(38.3%) had raised d dimer levels, 69(73.4%) had raised ferritin levels and 28(29.8%) had raised LDH levels. 9 patients required non-invasive support and 11 needed invasive oxygen support. Out of total 94 patients, 10(10.6%) did not survive. CONCLUSIONS- Most children acquired infection through household contacts. Although lower incidence than adults, children too have severe COVID-19 infections. The presence of a comorbid illness in pediatric patients with COVID-19 did not impact the severity in our study

Effect of prone positioning and high flow nasal oxygen on oxygenation and overall outcome in spontaneously breathing awake patient with severe COVID-19 induced acute hypoxemic respiratory failure: A prospective observational study

BackgroundPrevious studies suggest that prone positioning can increase PaO2/FiO2 and reduce mortality in moderate to severe acute respiratory distress syndrome. Effect of prone positioning and high flow nasal oxygen has been studied individually in COVID-19 patients but their combined effect on patient's outcome is yet to be reported. MethodsIn this study 120 severe COVID-19 positive patients were included and placed in awake prone positioning with high flow nasal oxygen. The efficacy in improving oxygenation with prone positioning and high flow nasal oxygen were evaluated by blood gas analysis. The primary outcome was a proportion of patients requiring non-invasive ventilation or invasive ventilation. The secondary outcomes were a comparison of arterial blood gas parameters and biochemical inflammatory parameters pre proning, end of first proning and end of last prone position in these patients. ResultsWe found only 35 patients (34.3%) required the need for non-invasive or invasive mechanical ventilation support whereas 67 patients (65.7%) were managed successfully on high flow nasal oxygen along with awake prone positioning (p = 0.001). We found there were statistically significant improvements in arterial blood gas parameters and biochemical inflammatory markers after the end of last prone positioning with high flow nasal oxygen. ConclusionsEarly application of prone positioning in combination with high flow nasal oxygen may help in avoiding mechanical ventilation by improving oxygenation and biochemical inflammatory markers.

Evaluation of Trends in Bronchopulmonary Dysplasia and Respiratory Support Practice for Very Low Birth Weight Infants: A Population-Based Cohort Study

To characterize the incidence of bronchopulmonary dysplasia (BPD) over time and to test the association of multilevel factors, including respiratory support, with the diagnosis of BPD. This population-based cohort study included 40 268 infants born between 22 and 32weeks of gestation at hospitals in California between 2008 and 2017. The diagnosis of BPD was based on respiratory support at 36weeks postmenstrual age. Tests for linear trend and multivariable logistic regression analyses were performed. The rate of BPD was consistent year to year, and the mortality rate declined. The incidence of BPD was 23.5% for the overall cohort, 44.9% for infants born at <28weeks of gestational age, and 45.2% for extremely low birth weight infants. For infants born at >26weeks of gestational age, the incidence of BPD was significantly decreased in the most recent 3-year period compared with the earlier 3years (OR, 0.91). Invasive ventilation during delivery room resuscitation (OR, 2.64) and after leaving the delivery room (OR, 10.02) conferred the highest risk of BPD compared with oxygen or no respiratory support. Noninvasive ventilation as maximum respiratory support at 36weeks increased by 20% over time. Marked changes in noninvasive support care have occurred without an overall decline in BPD rate. Further research, quality improvement, and strategies, along with noninvasive respiratory support, are needed for a reduction in the incidence of BPD.

A non-invasive, automated diagnosis of Meni\xe8re\u2019s disease using radiomics and machine learning on conventional magnetic resonance imaging: A multicentric, case-controlled feasibility study

PurposeThis study investigated the feasibility of a new image analysis technique (radiomics) on conventional MRI for the computer-aided diagnosis of Menière’s disease.Materials and methodsA retrospective, multicentric diagnostic case–control study was performed. This study included 120 patients with unilateral or bilateral Menière’s disease and 140 controls from four centers in the Netherlands and Belgium. Multiple radiomic features were extracted from conventional MRI scans and used to train a machine learning-based, multi-layer perceptron classification model to distinguish patients with Menière’s disease from controls. The primary outcomes were accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of the classification model.ResultsThe classification accuracy of the machine learning model on the test set was 82%, with a sensitivity of 83%, and a specificity of 82%. The positive and negative predictive values were 71%, and 90%, respectively.ConclusionThe multi-layer perceptron classification model yielded a precise, high-diagnostic performance in identifying patients with Menière’s disease based on radiomic features extracted from conventional T2-weighted MRI scans. In the future, radiomics might serve as a fast and noninvasive decision support system, next to clinical evaluation in the diagnosis of Menière’s disease.

Pediatric Inflammatory Multisystem Syndrome Temporally Associated with SARS-CoV-2.

ObjectivesTo know the clinical presentation and outcome of children with pediatric inflammatory multisystem syndrome temporally associated with SARS-CoV- 2 (PIMS-TS) at a pediatric tertiary care center in Chennai.MethodsClinical and biochemical parameters of 65 children with PIMS-TS treated between July and October 2020 were studied. All children had their COVID RT-PCR and IgG COVID antibodies tests done.ResultsMean age of the study group was 5.65 ± 3.68 y. Fever with red eyes, rash, vomiting, abdominal pain, and shock were common presenting features. Sixty percent of the study group had Kawasaki/incomplete Kawasaki features. Sixty-seven percent of the study group had coronary dilatation, 41% presented with shock, and 25% had left ventricular dysfunction. Coronary aneurysms were documented in 58% of the study group (z score more than 2.5). Respiratory presentation with pneumonia was seen in 10%. Four children presented with acute abdomen. Acute kidney injury, acute liver failure, hemolysis, pancytopenia, macrophage activation syndrome, encephalopathy, and multiorgan dysfunction syndrome (MODS) were other features. Forty-three percent required noninvasive oxygen support and 15.4% required mechanical ventilation. Intravenous immunoglobulin (73.8%) and methylprednisolone (49.8%) were used for therapy. Mortality in the study was 6%, which was due to MODS.ConclusionsAcute febrile illness with mucocutaneous and gastrointestinal manifestations should have PIMS-TS as a possible differential diagnosis and needs evaluation with inflammatory markers and SARS-CoV-2 antibodies.

Extracorporeal Membrane Oxygenation for COVID 2019-Acute Respiratory Distress Syndrome: Comparison between First and Second Waves (Stage 2).

We aimed to compare the outcomes of patients under veno-venous extracorporeal membrane oxygenation (V-V ECMO) for COVID-19-Acute Respiratory Distress Syndrome (CARDS) between the first and the second wave. From 1 March 2020 to 30 November 2020, fifty patients requiring a V-V ECMO support for CARDS were included. Patient demographics, pre-ECMO, and day one, three, and seven on-ECMO data and outcomes were collected. The 90-day mortality was 11% higher during the second wave (18/26 (69%)) compared to the first wave (14/24 (58%) (p = 0.423). During the second wave, all of the patients were given steroids compared to 16.7% during the first wave (p < 0.001). The second wave’s patients had been on non-invasive ventilation support for a longer period than in the first wave, with the median time from ICU admission to ECMO implantation being significantly higher (14 (11–20) vs. 7.7 (5–12) days; p < 0.001). Mechanical properties of the lung were worsened in the second wave’s CARDS patients before ECMO implantation (median static compliance 20 (16–26) vs. 29 (25–37) mL/cmH2O; p < 0.001) and during ECMO days one, three, and seven. More bacterial co-infections before implantation and under ECMO were documented in the second wave group. Despite a better evidence-driven critical care management, we depicted fewer encouraging outcomes during the second wave.

COVID-19 pneumonia: pathophysiology and management.

Coronavirus disease 2019 (COVID-19) pneumonia is an evolving disease. We will focus on the development of its pathophysiologic characteristics over time, and how these time-related changes determine modifications in treatment. In the emergency department: the peculiar characteristic is the coexistence, in a significant fraction of patients, of severe hypoxaemia, near-normal lung computed tomography imaging, lung gas volume and respiratory mechanics. Despite high respiratory drive, dyspnoea and respiratory rate are often normal. The underlying mechanism is primarily altered lung perfusion. The anatomical prerequisites for PEEP (positive end-expiratory pressure) to work (lung oedema, atelectasis, and therefore recruitability) are lacking. In the high-dependency unit: the disease starts to worsen either because of its natural evolution or additional patient self-inflicted lung injury (P-SILI). Oedema and atelectasis may develop, increasing recruitability. Noninvasive supports are indicated if they result in a reversal of hypoxaemia and a decreased inspiratory effort. Otherwise, mechanical ventilation should be considered to avert P-SILI. In the intensive care unit: the primary characteristic of the advance of unresolved COVID-19 disease is a progressive shift from oedema or atelectasis to less reversible structural lung alterations to lung fibrosis. These later characteristics are associated with notable impairment of respiratory mechanics, increased arterial carbon dioxide tension (PaCO2), decreased recruitability and lack of response to PEEP and prone positioning.

Respiratory Drive in Patients with Sepsis and Septic Shock: Modulation by High-flow Nasal Cannula.

Experimental and pilot clinical data suggest that spontaneously breathing patients with sepsis and septic shock may present increased respiratory drive and effort, even in the absence of pulmonary infection. The study hypothesis was that respiratory drive and effort may be increased in septic patients and correlated with extrapulmonary determinant and that high-flow nasal cannula may modulate drive and effort. Twenty-five nonintubated patients with extrapulmonary sepsis or septic shock were enrolled. Each patient underwent three consecutive steps: low-flow oxygen at baseline, high-flow nasal cannula, and then low-flow oxygen again. Arterial blood gases, esophageal pressure, and electrical impedance tomography data were recorded toward the end of each step. Respiratory effort was measured as the negative swing of esophageal pressure (ΔPes); drive was quantified as the change in esophageal pressure during the first 500 ms from start of inspiration (P0.5). Dynamic lung compliance was calculated as the tidal volume measured by electrical impedance tomography, divided by ΔPes. The results are presented as medians [25th to 75th percentile]. Thirteen patients (52%) were in septic shock. The Sequential Organ Failure Assessment score was 5 [4 to 9]. During low-flow oxygen at baseline, respiratory drive and effort were elevated and significantly correlated with arterial lactate (r = 0.46, P = 0.034) and inversely with dynamic lung compliance (r = -0.735, P < 0.001). Noninvasive support by high-flow nasal cannula induced a significant decrease of respiratory drive (P0.5: 6.0 [4.4 to 9.0] vs. 4.3 [3.5 to 6.6] vs. 6.6 [4.9 to 10.7] cm H2O, P < 0.001) and effort (ΔPes: 8.0 [6.0 to 11.5] vs. 5.5 [4.5 to 8.0] vs. 7.5 [6.0 to 12.6] cm H2O, P < 0.001). Oxygenation and arterial carbon dioxide levels remained stable during all study phases. Patients with sepsis and septic shock of extrapulmonary origin present elevated respiratory drive and effort, which can be effectively reduced by high-flow nasal cannula.

Bronchoscopy during COVID-19 pandemic, ventilatory strategies and procedure measures.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has changed bronchoscopy practices worldwide. Bronchoscopy is a high-risk aerosol-generating procedure with a potential for direct SARS-CoV-2 exposure and hospital-acquired infection. Current guidelines about personal protective equipment and environment considerations represent key competencies to minimize droplets dispersion and reduce the risk of transmission. Different measures should be put in field based on setting, patient's clinical characteristics, urgency and indications of bronchoscopy. The use of this technique in SARS-CoV-2 patients is reported primarily for removal of airway plugs and for obtaining microbiological culture samples. In mechanically ventilated patients with SARS-CoV-2, bronchoscopy is commonly used to manage complications such as hemoptysis, atelectasis or lung collapse when prone positioning, physiotherapy or recruitment maneuvers have failed. Further indications are represented by assistance during percutaneous tracheostomy. Continuous positive airway pressure, non-invasive ventilation support and high flow nasal cannula oxygen are frequently used in patient affected by Coronavirus disease 2019 (COVID-19): management of patients' airways and ventilation strategies differs from bronchoscopy indications, patient's clinical status and in course or required ventilatory support. Sedation is usually administered by the pulmonologist (performing the bronchoscopy) or by the anesthetist depending on the complexity of the procedure and the level of sedation required. Lastly, elective bronchoscopy for diagnostic indications during COVID-19 pandemic should be carried on respecting rigid standards which allow to minimize potential viral transmission, independently from patient's COVID-19 status. This narrative review aims to evaluate the indications, procedural measures and ventilatory strategies of bronchoscopy performed in different settings during COVID-19 pandemic.

Diagnostic test accuracy of artificial intelligence analysis of cross-sectional imaging in pulmonary hypertension: a systematic literature review.

To undertake the first systematic review examining the performance of artificial intelligence (AI) applied to cross-sectional imaging for the diagnosis of acquired pulmonary arterial hypertension (PAH). Searches of Medline, Embase and Web of Science were undertaken on 1 July 2020. Original publications studying AI applied to cross-sectional imaging for the diagnosis of acquired PAH in adults were identified through two-staged double-blinded review. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies and Checklist for Artificial Intelligence in Medicine frameworks. Narrative synthesis was undertaken following Synthesis Without Meta-Analysis guidelines. This review received no funding and was registered in the International Prospective Register of Systematic Reviews (ID:CRD42020196295). Searches returned 476 citations. Three retrospective observational studies, published between 2016 and 2020, were selected for data-extraction. Two methods applied to cardiac-MRI demonstrated high diagnostic accuracy, with the best model achieving AUC=0.90 (95% CI: 0.85-0.93), 89% sensitivity and 81% specificity. Stronger results were achieved using cardiac-MRI for classification of idiopathic PAH, achieving AUC=0.97 (95% CI: 0.89-1.0), 96% sensitivity and 87% specificity. One study reporting CT-based AI demonstrated lower accuracy, with 64.6% sensitivity and 97.0% specificity. Automated methods for identifying PAH on cardiac-MRI are emerging with high diagnostic accuracy. AI applied to cross-sectional imaging may provide non-invasive support to reduce diagnostic delay in PAH. This would be helped by stronger solutions in other modalities. There is a significant shortage of research in this important area. Early detection of PAH would be supported by further research advances on the promising emerging technologies identified.