An appraisal of respiratory system compliance in mechanically ventilated covid-19 patients

Abstract Background Heterogeneous respiratory system static compliance (CRS) values and levels of hypoxemia in patients with novel coronavirus disease (COVID-19) requiring mechanical ventilation have been reported in previous small-case series or studies conducted at a national level. Methods We designed a retrospective observational cohort study with rapid data gathering from the international COVID-19 Critical Care Consortium study to comprehensively describe CRS—calculated as: tidal volume/[airway plateau pressure-positive end-expiratory pressure (PEEP)]—and its association with ventilatory management and outcomes of COVID-19 patients on mechanical ventilation (MV), admitted to intensive care units (ICU) worldwide. Results We studied 745 patients from 22 countries, who required admission to the ICU and MV from January 14 to December 31, 2020, and presented at least one value of CRS within the first seven days of MV. Median (IQR) age was 62 (52–71), patients were predominantly males (68%) and from Europe/North and South America (88%). CRS, within 48 h from endotracheal intubation, was available in 649 patients and was neither associated with the duration from onset of symptoms to commencement of MV (p = 0.417) nor with PaO2/FiO2 (p = 0.100). Females presented lower CRS than males (95% CI of CRS difference between females-males: − 11.8 to − 7.4 mL/cmH2O p < 0.001), and although females presented higher body mass index (BMI), association of BMI with CRS was marginal (p = 0.139). Ventilatory management varied across CRS range, resulting in a significant association between CRS and driving pressure (estimated decrease − 0.31 cmH2O/L per mL/cmH20 of CRS, 95% CI − 0.48 to − 0.14, p < 0.001). Overall, 28-day ICU mortality, accounting for the competing risk of being discharged within the period, was 35.6% (SE 1.7). Cox proportional hazard analysis demonstrated that CRS (+ 10 mL/cm H2O) was only associated with being discharge from the ICU within 28 days (HR 1.14, 95% CI 1.02–1.28, p = 0.018). Conclusions This multicentre report provides a comprehensive account of CRS in COVID-19 patients on MV. CRS measured within 48 h from commencement of MV has marginal predictive value for 28-day mortality, but was associated with being discharged from ICU within the same period. Trial documentation: Available at https://www.covid-critical.com/study. Trial registration: ACTRN12620000421932.

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An Appraisal of Respiratory System Compliance In Mechanically Ventilated Covid-19 Patients

10.21203/rs.3.rs-125428/v1 ◽

2020 ◽

Author(s):

Gianluigi Li Bassi ◽

Jacky Suen ◽

Heidi Dalton ◽

Nicole White ◽

Sally Shrapnel ◽

...

Keyword(s):

Mechanical Ventilation ◽

Respiratory System ◽

National Level ◽

Data Gathering ◽

Case Series ◽

Plateau Pressure ◽

Mechanically Ventilated ◽

Observational Cohort ◽

Novel Coronavirus ◽

The Impact

Abstract Background Heterogeneous respiratory system static compliance (CRS) values and levels of hypoxemia in patients with novel coronavirus disease (COVID-19) requiring mechanical ventilation have been reported in previous small-case series or studies conducted at a national level. Methods We designed a retrospective observational cohort study with rapid data gathering from the international COVID-19 Critical Care Consortium study to comprehensively describe the impact of CRS on the ventilatory management and outcomes of COVID-19 patients on mechanical ventilation (MV), admitted to intensive care units (ICU) worldwide. Results We enrolled 318 COVID-19 patients enrolled into the study from January 14th through September 31th, 2020 in 19 countries and stratified into two CRS groups. CRS was calculated as: tidal volume/[airway plateau pressure-positive end-expiratory pressure (PEEP)] and available within 48 h from commencement of MV in 318 patients. Patients were mean ± SD of 58.0 ± 12.2, predominantly from Europe (54%) and males (68%). Median CRS (IQR) was 34.1 mL/cmH2O (26.5–45.5) and PaO2/FiO2 was 119 mmHg (87.1–164) and was not correlated with CRS. Female sex presented lower CRS than in males (95% CI: -13.8 to -8.5 P < 0.001) and higher body mass index (34.7 ± 10.9 vs 29.1 ± 6.0, p < 0.001). Median (IQR) PEEP was 12 cmH2O (10–15), throughout the range of CRS, while median (IQR) driving pressure was 12.3 (10–15) cmH2O and significantly decreased as CRS improved (p < 0.001). No differences were found in comorbidities and clinical management between CRS strata. In addition, 28-day ICU mortality and hospital mortality did not differ between CRS groups. Conclusions This multicentre report provides a comprehensive account of CRS in COVID-19 patients on MV – predominantly males or overweight females, in their late 50 s – admitted to ICU during the first international outbreaks. Phenotypes associated with different CRS upon commencement of MV could not be identified. Trial documentation: Available at https://www.covid-critical.com/study. Trial registration ACTRN12620000421932.

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Clinical features and predictors of severity in COVID-19 patients with critical illness in Singapore

Scientific Reports ◽

10.1038/s41598-021-81377-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ser Hon Puah ◽

◽

Barnaby Edward Young ◽

Po Ying Chia ◽

Vui Kian Ho ◽

...

Keyword(s):

Mechanical Ventilation ◽

Clinical Features ◽

Operating Characteristic ◽

Characteristic Curve ◽

Case Series ◽

Plateau Pressure ◽

Apache Ii Score ◽

Multivariable Logistic Regression Model ◽

Reactive Protein ◽

Ventilatory Management

AbstractWe aim to describe a case series of critically and non-critically ill COVID-19 patients in Singapore. This was a multicentered prospective study with clinical and laboratory details. Details for fifty uncomplicated COVID-19 patients and ten who required mechanical ventilation were collected. We compared clinical features between the groups, assessed predictors of intubation, and described ventilatory management in ICU patients. Ventilated patients were significantly older, reported more dyspnea, had elevated C-reactive protein and lactate dehydrogenase. A multivariable logistic regression model identified respiratory rate (aOR 2.83, 95% CI 1.24–6.47) and neutrophil count (aOR 2.39, 95% CI 1.34–4.26) on admission as independent predictors of intubation with area under receiver operating characteristic curve of 0.928 (95% CI 0.828–0.979). Median APACHE II score was 19 (IQR 17–22) and PaO2/FiO2 ratio before intubation was 104 (IQR 89–129). Median peak FiO2 was 0.75 (IQR 0.6–1.0), positive end-expiratory pressure 12 (IQR 10–14) and plateau pressure 22 (IQR 18–26) in the first 24 h of ventilation. Median duration of ventilation was 6.5 days (IQR 5.5–13). There were no fatalities. Most COVID-19 patients in Singapore who required mechanical ventilation because of ARDS were extubated with no mortality.

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The correlation of respiratory system compliance and mortality in COVID-19 acute respiratory distress syndrome: do phenotypes really exist?

Journal of Lung Pulmonary & Respiratory Research ◽

10.15406/jlprr.2021.08.00253 ◽

2021 ◽

Vol 8 (2) ◽

pp. 67-74

Author(s):

Rachel L. Choron ◽

Stephen A. Iacono ◽

Alexander Cong ◽

Christopher G. Bargoud ◽

Amanda L. Teichman ◽

...

Keyword(s):

Mechanical Ventilation ◽

Respiratory System ◽

Management Strategies ◽

Respiratory System Compliance ◽

Risk Of Death ◽

Mortality Difference ◽

Ventilator Management ◽

Observational Cohort ◽

Multivariable Regression ◽

The Mean

Background: Recent literature suggests respiratory system compliance (Crs) based phenotypes exist among COVID-19 ARDS patients. We sought to determine whether these phenotypes exist and whether Crs predicts mortality. Methods: A retrospective observational cohort study of 111 COVID-19 ARDS patients admitted March 11-July 8, 2020. Crs was averaged for the first 72-hours of mechanical ventilation. Crs<30ml/cmH2O was defined as poor Crs(phenotype-H) whereas Crs≥30ml/cmH2O as preserved Crs(phenotype-L). Results: 111 COVID-19 ARDS patients were included, 40 phenotype-H and 71 phenotype-L. Both the mean PaO2/FiO2 ratio for the first 72-hours of mechanical ventilation and the PaO2/FiO2 ratio hospital nadir were lower in phenotype-H than L(115[IQR87] vs 165[87], p=0.016), (63[32] vs 75[59], p=0.026). There were no difference in characteristics, diagnostic studies, or complications between groups. Twenty-seven (67.5%) phenotype-H patients died vs 37(52.1%) phenotype-L(p=0.115). Multivariable regression did not reveal a mortality difference between phenotypes; however, a 2-fold mortality increase was noted in Crs<20 vs >50ml/cmH2O when analyzing ordinal Crs groups. Moving up one group level (ex. Crs30-39.9ml/cmH2O to 40-49.9ml/cmH2O), was marginally associated with 14% lower risk of death(RR=0.86, 95%CI 0.72, 1.01, p=0.065). This attenuated (RR=0.94, 95%CI 0.80, 1.11) when adjusting for pH nadir and PaO2/FiO2 ratio nadir. Conclusion: We identified a spectrum of Crs in COVID-19 ARDS similar to Crs distribution in non-COVID-19 ARDS. While we identified increasing mortality as Crs decreased, there was no specific threshold marking significantly different mortality based on phenotype. We therefore would not define COVID-19 ARDS patients by phenotypes-H or L and would not stray from traditional ARDS ventilator management strategies.

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Covid-19 pneumonia: Timing of pneumomediastinum and pneumothorax in 11 patients

Discussion of Clinical Cases ◽

10.5430/dcc.v8n2p1 ◽

2021 ◽

Vol 8 (2) ◽

pp. 1

Author(s):

Mostafa Al Turk ◽

Maria Mitri ◽

Kawthar Jarrah ◽

Joanna Abi Chebl ◽

Georges Juvelekian

Keyword(s):

Risk Factors ◽

Mechanical Ventilation ◽

Case Series ◽

Plateau Pressure ◽

Acceptable Range ◽

Lung Protective Strategy ◽

Protective Strategy ◽

Acute Event ◽

Shed Light

Purpose: As the pandemic continues, many complications, previously recognized as rare, are now being reported as more than frequent complications of Covid-19 pneumonia. Of those, pneumomediastinum and pneumothorax are gaining attention. Their mechanism of occurrence/trigger is not fully understood, but the timing at which they occur is unclear.Methods: This is a case series of 11 Covid-19 patients with pneumomediastinum; retrospectively, we shed light on some of the patients’ characteristics, the role of mechanical ventilation, and the timing of pneumomediastinum after initiation of mechanical ventilation.Results: We found that despite following the lung-protective strategy and despite keeping a plateau pressure at an acceptable range, most of our patients had an acute event around the same timing of mechanical ventilation.Conclusions: The similar timing raises questions about other risk factors that remain unknown. Timing and steroids can contribute to the higher incidence of these complications.

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Ventilated Patients With COVID-19 Show Airflow Obstruction

Journal of Intensive Care Medicine ◽

10.1177/08850666211000601 ◽

2021 ◽

pp. 088506662110006

Author(s):

Vikas S. Koppurapu ◽

Maksym Puliaiev ◽

Kevin C. Doerschug ◽

Gregory A. Schmidt

Keyword(s):

Mechanical Ventilation ◽

Respiratory System ◽

Invasive Mechanical Ventilation ◽

Airflow Obstruction ◽

Plateau Pressure ◽

Control Mode ◽

Volume Control ◽

Respiratory System Compliance ◽

University Of Iowa ◽

The University

Objective: Many patients with coronavirus disease 2019 (COVID-19) need mechanical ventilation secondary to acute respiratory distress syndrome. Information on the respiratory system mechanical characteristics of this disease is limited. The aim of this study is to describe the respiratory system mechanical properties of ventilated COVID-19 patients. Design, Setting, and Patients: Patients consecutively admitted to the medical intensive care unit at the University of Iowa Hospitals and Clinics in Iowa City, USA, from April 19 to May 1, 2020, were prospectively studied; final date of follow-up was May 1, 2020. Measurements: At the time of first patient contact, ventilator information was collected including mode, settings, peak airway pressure, plateau pressure, and total positive end expiratory pressure. Indices of airflow resistance and respiratory system compliance were calculated and analyzed. Main Results: The mean age of the patients was 58 years. 6 out of 12 (50%) patients were female. Of the 21 laboratory-confirmed COVID-19 patients on invasive mechanical ventilation, 9 patients who were actively breathing on the ventilator were excluded. All the patients included were on volume-control mode. Mean [±standard deviation] ventilator indices were: resistive pressure 19 [±4] cmH2O, airway resistance 20 [±4] cmH2O/L/s, and respiratory system static compliance 39 [±16] ml/cmH2O. These values are consistent with abnormally elevated resistance to airflow and reduced respiratory system compliance. Analysis of flow waveform graphics revealed a pattern consistent with airflow obstruction in all patients. Conclusions: Severe respiratory failure due to COVID-19 is regularly associated with airflow obstruction.

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Respiratory Care in Children with COVID-19

Journal of Pediatric Intensive Care ◽

10.1055/s-0041-1723036 ◽

2021 ◽

Author(s):

Shalu Gupta ◽

Suresh K. Angurana ◽

Virendra Kumar

Keyword(s):

Mechanical Ventilation ◽

Respiratory Distress ◽

Health Care Providers ◽

Respiratory System ◽

Oxygen Delivery ◽

Invasive Mechanical Ventilation ◽

Respiratory Support ◽

Critically Ill Children ◽

Care Providers ◽

Novel Coronavirus

AbstractThe novel coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) is causing significant morbidity and mortality worldwide. The common presentations in children include involvement of respiratory system leading to pneumonia and acute respiratory distress syndrome, as well as multiorgan dysfunction syndrome and multisystem inflammatory syndrome in children (MIS-C). Pediatric COVID-19 is a milder disease as compared with the adults. Also, there is rise in MIS-C cases which is a hyperinflammatory condition temporally associated with SARS-CoV-2. Since respiratory system is predominantly involved, few of these critically ill children often require respiratory support which can range from simple oxygen delivery devices, high-flow nasal cannula (HFNC), noninvasive ventilation (NIV), invasive mechanical ventilation, and extracorporeal membrane oxygenation (ECMO). Most of the oxygen delivery devices and respiratory interventions generate aerosols and pose risk of transmission of virus to health care providers (HCPs). The use of HFNC and NIV should be limited to children with mild respiratory distress preferably in negative pressure rooms and with adequate personnel protective equipments (PPEs). However, there should be low thresholds for intubation and invasive mechanical ventilation in the event of clinical deterioration while on any respiratory support. The principle of providing respiratory support requires special droplet and air-borne precautions to limit exposure or transmission of virus to HCPs and at the same time ensuring safety of the patient.

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Management of pneumothorax in mechanically ventilated COVID-19 patients: early experience

Interactive CardioVascular and Thoracic Surgery ◽

10.1093/icvts/ivaa129 ◽

2020 ◽

Vol 31 (4) ◽

pp. 540-543

Author(s):

Azhar Hussain ◽

Alia Noorani ◽

Ranjit Deshpande ◽

Lindsay John ◽

Max Baghai ◽

...

Keyword(s):

Mechanical Ventilation ◽

Intensive Care ◽

Best Practice ◽

Significant Proportion ◽

Case Series ◽

Chest Drain ◽

The Novel ◽

Intensive Care Admission ◽

Mechanically Ventilated ◽

Novel Coronavirus

Abstract A significant proportion of patients infected with the novel coronavirus, now termed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), require intensive care admission and subsequent mechanical ventilation. Pneumothorax, a potential fatal complication of mechanical ventilation, can further complicate the management of COVID-19 patients, whilst chest drain insertion may increase the risk of transmission of attending staff. We present a case series and a suggested best-practice protocol for how to manage and treat pneumothoraces in COVID-19 patients in an intensive care unit setting.

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Goal-Directed Mechanical Ventilation: Are We Aiming at the Right Goals? A Proposal for an Alternative Approach Aiming at Optimal Lung Compliance, Guided by Esophageal Pressure in Acute Respiratory Failure

Critical Care Research and Practice ◽

10.1155/2012/597932 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 4

Author(s):

Arie Soroksky ◽

Antonio Esquinas

Keyword(s):

Mechanical Ventilation ◽

Respiratory Failure ◽

Acute Respiratory Failure ◽

Chest Wall ◽

Respiratory System ◽

Transpulmonary Pressure ◽

Esophageal Pressure ◽

Plateau Pressure ◽

Lung Compliance ◽

Inspiratory Pressure

Patients with acute respiratory failure and decreased respiratory system compliance due to ARDS frequently present a formidable challenge. These patients are often subjected to high inspiratory pressure, and in severe cases in order to improve oxygenation and preserve life, we may need to resort to unconventional measures. The currently accepted ARDSNet guidelines are characterized by a generalized approach in which an algorithm for PEEP application and limited plateau pressure are applied to all mechanically ventilated patients. These guidelines do not make any distinction between patients, who may have different chest wall mechanics with diverse pathologies and different mechanical properties of their respiratory system. The ability of assessing pleural pressure by measuring esophageal pressure allows us to partition the respiratory system into its main components of lungs and chest wall. Thus, identifying the dominant factor affecting respiratory system may better direct and optimize mechanical ventilation. Instead of limiting inspiratory pressure by plateau pressure, PEEP and inspiratory pressure adjustment would be individualized specifically for each patient's lung compliance as indicated by transpulmonary pressure. The main goal of this approach is to specifically target transpulmonary pressure instead of plateau pressure, and therefore achieve the best lung compliance with the least transpulmonary pressure possible.

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The Correlation of Respiratory System Compliance and Mortality in COVID-19 Acute Respiratory Distress Syndrome: Do Phenotypes Really Exist?

10.21203/rs.3.rs-390496/v1 ◽

2021 ◽

Author(s):

Rachel L. Choron ◽

Stephen A. Iacono ◽

Alexander Cong ◽

Christopher G. Bargoud ◽

Amanda L. Teichman ◽

...

Keyword(s):

Mechanical Ventilation ◽

Respiratory System ◽

Management Strategies ◽

Respiratory System Compliance ◽

Risk Of Death ◽

Mortality Difference ◽

Ventilator Management ◽

Observational Cohort ◽

Multivariable Regression ◽

The Mean

Abstract Background: Recent literature suggests respiratory system compliance (Crs) based phenotypes exist among COVID-19 ARDS patients. We sought to determine whether these phenotypes exist and whether Crs predicts mortality. Methods: A retrospective observational cohort study of 111 COVID-19 ARDS patients admitted March 11-July 8, 2020. Crs was averaged for the first 72-hours of mechanical ventilation. Crs < 30ml/cmH2O was defined as poor Crs(phenotype-H) whereas Crs ≥ 30ml/cmH2O as preserved Crs(phenotype-L). Results: 111 COVID-19 ARDS patients were included, 40 phenotype-H and 71 phenotype-L. Both the mean PaO2/FiO2 ratio for the first 72-hours of mechanical ventilation and the PaO2/FiO2 ratio hospital nadir were lower in phenotype-H than L(115[IQR87] vs 165[87], p = 0.016), (63[32] vs 75[59], p = 0.026). There were no difference in characteristics, diagnostic studies, or complications between groups. Twenty-seven (67.5%) phenotype-H patients died vs 37(52.1%) phenotype-L(p = 0.115). Multivariable regression did not reveal a mortality difference between phenotypes; however, a 2-fold mortality increase was noted in Crs < 20 vs > 50ml/cmH2O when analyzing ordinal Crs groups. Moving up one group level (ex. Crs30-39.9ml/cmH2O to 40-49.9ml/cmH2O), was marginally associated with 14% lower risk of death(RR = 0.86, 95%CI 0.72, 1.01, p = 0.065). This attenuated(RR = 0.94, 95%CI 0.80, 1.11) when adjusting for pH nadir and PaO2/FiO2 ratio nadir. Conclusion: We identified a spectrum of Crs in COVID-19 ARDS similar to Crs distribution in non-COVID-19 ARDS. While we identified increasing mortality as Crs decreased, there was no specific threshold marking significantly different mortality based on phenotype. We therefore would not define COVID-19 ARDS patients by phenotypes-H or L and would not stray from traditional ARDS ventilator management strategies.

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TBE in Italy

Tick-borne encephalitis - The Book ◽

10.33442/26613980_12b15-3 ◽

2020 ◽

Keyword(s):

Surveillance System ◽

Ad Hoc ◽

National Level ◽

Case Series ◽

Incidence Rates ◽

Mountainous Regions ◽

North East ◽

The North ◽

Tick Borne Encephalitis ◽

Low Incidence

Italy is considered a low-incidence country for tick-borne encephalitis (TBE) in Europe.1 Areas at higher risk for TBE in Italy are geographically clustered in the forested and mountainous regions and provinces in the north east part of the country, as suggested by TBE case series published over the last decade.2-5 A national enhanced surveillance system for TBE has been established since 2017.6 Before this, information on the occurrence of TBE cases at the national level in Italy was lacking. Both incidence rates and the geographical distribution of the disease were mostly inferred from endemic areas where surveillance was already in place, ad hoc studies and international literature.1

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