Non-invasive Respiratory Support in COVID-19: A Narrative Review

Post-discharge spirometry evaluation in patients recovering from moderate-to-critical COVID-19: a cross-sectional study

Understanding the prevalence of abnormal lung function and its associated factors among patients recovering from COVID-19 is crucial for enhancing post-COVID care strategies. This study primarily aimed to determine the prevalence and types of spirometry abnormalities among post-COVID-19 patients in Malaysia, with a secondary objective of identifying its associated factors. Conducted at the COVID-19 Research Clinic, Faculty of Medicine, University Technology MARA, from March 2021 to December 2022, this study included patients at least three months post-discharge from hospitals following moderate-to-critical COVID-19. Of 408 patients studied, abnormal spirometry was found in 46.8%, with 28.4% exhibiting a restrictive pattern, 17.4% showing preserved ratio impaired spirometry (PRISm), and 1.0% displaying an obstructive pattern. Factors independently associated with abnormal spirometry included consolidation on chest X-ray (OR 8.1, 95% CI 1.75-37.42, p = 0.008), underlying cardiovascular disease (OR 3.5, 95% CI 1.19-10.47, p = 0.023), ground-glass opacity on chest X-ray (OR 2.6, 95% CI 1.52-4.30, p < 0.001), and oxygen desaturation during the 6-min walk test (OR 1.9, 95% CI 1.20-3.06, p = 0.007). This study highlights that patients recovering from moderate-to-critical COVID-19 often exhibit abnormal spirometry, notably a restrictive pattern and PRISm. Routine spirometry screening for high-risk patients is recommended.

Multidisciplinary Consensus on the Management of Non-Invasive Respiratory Support in the COVID-19 Patient

Acute respiratory failure due to COVID-19 pneumonia often requires a comprehensive approach that includes non-pharmacological strategies such as non-invasive support (including positive pressure modes, high flow therapy or awake proning) in addition to oxygen therapy, with the primary goal of avoiding endotracheal intubation. Clinical issues such as determining the optimal time to initiate non-invasive support, choosing the most appropriate modality (based not only on the acute clinical picture but also on comorbidities), establishing criteria for recognition of treatment failure and strategies to follow in this setting (including palliative care), or implementing de-escalation procedures when improvement occurs are of paramount importance in the ongoing management of severe COVID-19 cases. Organizational issues, such as the most appropriate setting for management and monitoring of the severe COVID-19 patient or protective measures to prevent virus spread to healthcare workers in the presence of aerosol-generating procedures, should also be considered. While many early clinical guidelines during the pandemic were based on previous experience with acute respiratory distress syndrome, the landscape has evolved since then. Today, we have a wealth of high-quality studies that support evidence-based recommendations to address these complex issues. This document, the result of a collaborative effort between four leading scientific societies (SEDAR, SEMES, SEMICYUC, SEPAR), draws on the experience of 25 experts in the field to synthesize knowledge to address pertinent clinical questions and refine the approach to patient care in the face of the challenges posed by severe COVID-19 infection.

Undernutrition risk is independently associated with worsened indicators of hospital rehabilitation in COVID-19 patients

OBJECTIVE

This study was designed to analyze the association between the risk of undernutrition and indicators of hospital rehabilitation in patients with COVID-19 while controlling for confounding variables.

METHODS

This was an analytical study conducted by analyzing the medical records of patients with COVID-19. A total of 562 adult patients were eligible for the study. In addition to the risk of undernutrition (independent variable), indicators of hospital rehabilitation (dependent variables) were evaluated. These indicators included the length of hospital stay, clinical outcome (discharge or death), food intake, mobility (bedridden status), the use of mechanical ventilation, and the need for enteral nutrition. Pre-existing comorbidities (confounding/control variables) were grouped into cardiovascular, metabolic/endocrine, neurological, chronic obstructive pulmonary disease, and other categories (neoplasms, multiple sclerosis, and kidney disease). A dichotomization model was applied for data analysis. The Chi-Square test was used to verify the association between the risk of undernutrition and the dependent variables. Associations with a significance level of P < 0.05 were subjected to Poisson regression to identify the prevalence ratio.

RESULTS

Patients at risk of undernutrition had a 90% higher chance of being bedridden and were 35 times more likely to experience a decrease in food intake. They also had an 89% higher chance of using invasive mechanical ventilation and a 91% higher chance of requiring enteral nutrition. Additionally, individuals at risk of undernutrition had a 73% higher chance of death. Adjustment for comorbidities did not alter these associations, demonstrating that the risk of undernutrition is independently associated with indicators of hospital rehabilitation.

CONCLUSION

The risk of undernutrition is independently associated with worsened indicators of hospital rehabilitation in patients with COVID-19, including higher prevalence of mortality.

Failure of Non-Invasive Respiratory Support in Patients with SARS-CoV-2

INTRODUCTION

The objective of this study is to assess the failure of therapies with HFNO (high-flow nasal oxygen), CPAP, Bilevel, or combined therapy in patients with hypoxemic acute respiratory failure due to SARS-CoV-2 during their hospitalization.

METHODS

This was a retrospective and observational study of SARS-CoV-2-positive patients who required non-invasive respiratory support (NIRS) at the Reina Sofía General University Hospital of Murcia between March 2020 and May 2021.

RESULTS

Of 7355 patients, 197 (11.8%) were included; 95 of them failed this therapy (48.3%). We found that during hospitalization in the ward, the combined therapy of HFNO and CPAP had an overall lower failure rate and the highest treatment with Bilevel (p = 0.005). In the comparison of failure in therapy without two levels of airway pressure, HFNO, CPAP, and combined therapy of HFNO with CPAP, (35.6% of patients) presented with 24.2% failure, compared to those who had two levels of pressure with Bilevel and combined therapy of HFNO with Bilevel (64.4% of patients), with 75.8% associated failure (OR: 0, 374; CI 95%: 0.203-0.688. p = 0.001).

CONCLUSIONS

The use of NIRS during conventional hospitalization is safe and effective in patients with respiratory failure secondary to SARS-CoV-2 infection. The therapeutic strategy of Bilevel increases the probability of failure, with the combined therapy strategy of CPAP and HFNO being the most promising option.

Feasibility and Short-Term SpO2/FiO2 Changes in Hospitalized Adults with COVID-19 Pneumonia after Chest Physiotherapy with Threshold PEP Valve: A Cross-Sectional Study

BACKGROUND

One of the main features of COVID-19 pneumonia is hypoxemic acute respiratory failure (ARF), often requiring ventilatory support. The influence of chest physiotherapy in patients with ARF is not extensively studied. The aim of the study was to analyze the short-time effects of chest physiotherapy using a 10 cm H2O threshold valve in patients with COVID-19 and ARF. Methods; Quasi-experimental cross-sectional study, in hospitalized patients from March to May 2020. The fractions of inspired oxygen, oxygen saturation, heart rate, respiratory rate and dyspnea were collected before and after the starting session (day 1) and after the 5th day of therapy.

RESULTS

The final sample size included 125 patients. Significant differences (p < 0.01) were found in the pre-post intervention SpO2/FiO2 ratio (250 ± 88.4 vs. 275.6 ± 97.5, p < 0.001), reaching 354.4 ± 110.2 after 5 days of therapy (p < 0.001 with respect to the baseline). The respiratory and heart rate dyspnea level did not change during the intervention. In patients needing FiO2 > 0.4, the SpO2/FiO2 ratio improvement was higher than in patients with milder severity (46.85 ± 77.69, p < 0.01).

CONCLUSIONS

Chest physiotherapy with a 10 cm H2O threshold valve seems to be a safe and tolerated intervention with short-term improvement in oxygenation in patients with COVID-19 pneumonia.

Lessons from COVID-19 in the management of acute respiratory failure

Accumulated evidence supports the efficacy of noninvasive respiratory support therapies in coronavirus disease 2019 (COVID-19)-related acute hypoxaemic respiratory failure, alleviating admissions to intensive care units. Noninvasive respiratory support strategies, including high-flow oxygen therapy, continuous positive airway pressure via mask or helmet and noninvasive ventilation, can be alternatives that may avoid the need for invasive ventilation. Alternating different noninvasive respiratory support therapies and introducing complementary interventions, like self-proning, may improve outcomes. Proper monitoring is warranted to ensure the efficacy of the techniques and to avoid complications while supporting transfer to the intensive care unit. This article reviews the latest evidence on noninvasive respiratory support therapies in COVID-19-related acute hypoxaemic respiratory failure.

Analysis of combined non-invasive respiratory support in the first six waves of the COVID-19 pandemic. Outcome according to the first respiratory support

Introduction

COVID-19 can lead to acute respiratory failure (ARF) requiring admission to intensive care unit (ICU). This study analyzes COVID-19 patients admitted to the ICU, according to the initial respiratory support. Its main aim is to determine if the use of combination therapy: high-flow oxygen system with nasal cannula (HFNC) and non-invasive ventilation (NIV), is effective and safe in the treatment of these patients.

Methods

Retrospective observational study with a prospective database. All COVID-19 patients, admitted to the ICU, between March 11, 2020, and February 12, 2022, and who required HFNC, NIV, or endotracheal intubation with invasive mechanical ventilation (ETI-IMV) were analyzed. HFNC failure was defined as therapeutic escalation to NIV, and NIV failure as the need for ETI-IMV or death in the ICU. The management of patients with non-invasive respiratory support included the use of combined therapy with different devices. The study period included the first six waves of the pandemic in Spain.

Results

424 patients were analyzed, of whom 12 (2.8%) received HFNC, 397 (93.7%) NIV and 15 (3.5%) ETI-IMV as first respiratory support. PaO2/FiO2 was 145 ± 30, 119 ± 26 and 117 ± 29 mmHg, respectively (p = 0.003). HFNC failed in 11 patients (91.7%), who then received NIV. Of the 408 patients treated with NIV, 353 (86.5%) received combination therapy with HFNC. In patients treated with NIV, there were 114 failures (27.9%). Only the value of SAPS II index (p = 0.001) and PaO2/FiO2 (p < 0.001) differed between the six analyzed waves, being the most altered values in the 3rd and 6th waves. Hospital mortality was 18.7%, not differing between the different waves (p = 0.713).

Conclusions

Severe COVID-19 ARF can be effectively and safely treated with NIV combined with HFNC. The clinical characteristics of the patients did not change between the different waves, only showing a slight increase in severity in the 3rd and 6th waves, with no difference in the outcome.

Non-invasive respiratory support in the management of COVID-19: a synthesis of systematic reviews

Hospitalised patients with COVID-19 often require oxygen because of the increased risk of hypoxia, and one of the main treatment goals is to avoid mechanical ventilation where possible. Non-invasive respiratory support such as high-flow nasal oxygen, bi-level positive airway pressure and continuous positive airway pressure appear to be clinical alternatives. However, further research is needed to assess the effectiveness of non-invasive respiratory support and its varying modes as a treatment for COVID-19 within a diverse population. This commentary aims to critically appraise three reviews concerning the use of non-invasive respiratory support in patients with COVID-19 and expand upon the findings with regards to clinical practice.

Comparison of high-flow nasal therapy, noninvasive ventilation, and continuous positive airway pressure on outcomes in critically ill patients admitted for COVID-19 with acute respiratory failure

BACKGROUND

The optimal first-line noninvasive respiratory support (NIRS) to improve outcome in patients affected by COVID-19 pneumonia admitted to ICU is still debated.

METHODS

We conducted a retrospective study in seven French ICUs, including all adults admitted between July and December 2020 with documented SARS-CoV-2 acute respiratory failure (PaO2/FiO2<300 mmHg), and treated with either high-flow nasal therapy (HFNT) alone, noninvasive ventilation alone or in combination with HFNT (NIV), or continuous positive airway pressure alone or in combination with HFNT (CPAP). The primary outcome was NIRS failure at day 28, defined as the need for endotracheal intubation (ETI) or death without ETI.

RESULTS

Among the 355 patients included, 160 (45%) were treated with HFNT alone, 115 (32%) with NIV and 80 (23%) with CPAP. The primary outcome occurred in 65 (41%), 69 (60%), and 25 (31%) patients among those treated with HFNT alone, NIV, and CPAP, respectively (P<0.001). After univariate analysis, patients treated with CPAP had a trend for a lower incidence of the primary outcome, whereas patients treated with NIV had a significant higher incidence of the primary outcome, both compared to those treated with HFNT alone (unadjusted Hazard ratio 0.67; 95% CI [0.42-1.06], and 1.58; 95% CI [1.12-2.22]; P=0.09 and 0.008, respectively).

CONCLUSIONS

Among ICU patients admitted for severe COVID-19 pneumonia and managed with NIRS, the outcome seems to differ according to the initial chosen strategy. Prospective randomized controlled studies are warranted to identify the optimal strategy.

Biological effects of COVID-19 on lung cancer: Can we drive our decisions

COVID-19 infection caused by SARS-CoV-2 is considered catastrophic because it affects multiple organs, particularly those of the respiratory tract. Although the consequences of this infection are not fully clear, it causes damage to the lungs, the cardiovascular and nervous systems, and other organs, subsequently inducing organ failure. In particular, the effects of SARS-CoV-2-induced inflammation on cancer cells and the tumor microenvironment need to be investigated. COVID-19 may alter the tumor microenvironment, promoting cancer cell proliferation and dormant cancer cell (DCC) reawakening. DCCs reawakened upon infection with SARS-CoV-2 can populate the premetastatic niche in the lungs and other organs, leading to tumor dissemination. DCC reawakening and consequent neutrophil and monocyte/macrophage activation with an uncontrolled cascade of pro-inflammatory cytokines are the most severe clinical effects of COVID-19. Moreover, neutrophil extracellular traps have been demonstrated to activate the dissemination of premetastatic cells into the lungs. Further studies are warranted to better define the roles of COVID-19 in inflammation as well as in tumor development and tumor cell metastasis; the results of these studies will aid in the development of further targeted therapies, both for cancer prevention and the treatment of patients with COVID-19.