Characteristics, outcomes and global trends of respiratory support in patients hospitalized with COVID-19 pneumonia: a scoping review

Acute dyspnea in the emergency department: a clinical review

Acute dyspnea represents one of the most frequent symptoms leading to emergency room evaluation. Its significant prognostic value warrants a careful evaluation. The differential diagnosis of dyspnea is complex due to the lack of specificity and the loose association between its intensity and the severity of the underlying pathological condition. The initial assessment of dyspnea calls for prompt diagnostic evaluation and identification of optimal monitoring strategy and provides information useful to allocate the patient to the most appropriate setting of care. In recent years, accumulating evidence indicated that lung ultrasound, along with echocardiography, represents the first rapid and non-invasive line of assessment that accurately differentiates heart, lung or extra-pulmonary involvement in patients with dyspnea. Moreover, non-invasive respiratory support modalities such as high-flow nasal oxygen and continuous positive airway pressure have aroused major clinical interest, in light of their efficacy and practicality to treat patients with dyspnea requiring ventilatory support, without using invasive mechanical ventilation. This clinical review is focused on the pathophysiology of acute dyspnea, on its clinical presentation and evaluation, including ultrasound-based diagnostic workup, and on available non-invasive modalities of respiratory support that may be required in patients with acute dyspnea secondary or associated with respiratory failure.

Acute Improvements of Oxygenation with Cpap and Clinical Outcomes in Severe COVID-19 Pneumonia: A Multicenter, Retrospective Study

It is not known if the degrees of improvement in oxygenation obtained by CPAP can predict clinical outcomes in patients with COVID-19 pneumonia. This was a retrospective study conducted on patients with severe COVID-19 pneumonia treated with CPAP in three University hospitals in Milan, Italy, from March 2020 to March 2021. Arterial gas analysis was obtained before and 1 h after starting CPAP. CPAP failure included either death in the respiratory units while on CPAP or the need for intubation. Two hundred and eleven patients (mean age 64 years, 74% males) were included. Baseline median PaO2, PaO2/FiO2 ratio (P/F), and the alveolar-arterial (A-a) O2 gradient were 68 (57−83) mmHg, 129 (91−179) mmHg and 310 (177−559) mmHg, respectively. Forty-two (19.9%) patients died in the respiratory units and 51 (24.2%) were intubated. After starting CPAP, PaO2/FiO2 increased by 57 (12−113; p < 0.001) mmHg, and (A-a) O2 was reduced by 68 (−25−250; p < 0.001) mmHg. A substantial overlap of PaO2, P/F, and A-a gradient at baseline and during CPAP was observed in CPAP failures and successes; CPAP-associated improvements in oxygenation in both groups were similar. In conclusion, CPAP-associated improvements in oxygenation do not predict clinical outcomes in patients with severe COVID-19 pneumonia.

High-Dose Dexamethasone and Oxygen Support Strategies in Intensive Care Unit Patients With Severe COVID-19 Acute Hypoxemic Respiratory Failure: The COVIDICUS Randomized Clinical Trial

IMPORTANCE

The benefit of high-dose dexamethasone and oxygenation strategies vs standard of care for patients with severe acute hypoxemic respiratory failure (AHRF) caused by COVID-19 pneumonia is debated.

OBJECTIVES

To assess the benefit of high-dose dexamethasone compared with standard of care dexamethasone, and to assess the benefit of high-flow nasal oxygen (HFNo2) or continuous positive airway pressure (CPAP) compared with oxygen support standard of care (o2SC).

DESIGN, SETTING, AND PARTICIPANTS

This multicenter, placebo-controlled randomized clinical trial was conducted in 19 intensive care units (ICUs) in France from April 2020 to January 2021. Eligible patients were consecutive ICU-admitted adults with COVID-19 AHRF. Randomization used a 2 × 3 factorial design for dexamethasone and oxygenation strategies; patients not eligible for at least 1 oxygenation strategy and/or already receiving invasive mechanical ventilation (IMV) were only randomized for dexamethasone. All patients were followed-up for 60 days. Data were analyzed from May 26 to July 31, 2021.

INTERVENTIONS

Patients received standard dexamethasone (dexamethasone-phosphate 6 mg/d for 10 days [or placebo prior to RECOVERY trial results communication]) or high-dose dexamethasone (dexamethasone-phosphate 20 mg/d on days 1-5 then 10 mg/d on days 6-10). Those not requiring IMV were additionally randomized to o2SC, CPAP, or HFNo2.

MAIN OUTCOMES AND MEASURES

The main outcomes were time to all-cause mortality, assessed at day 60, for the dexamethasone interventions, and time to IMV requirement, assessed at day 28, for the oxygenation interventions. Differences between intervention groups were calculated using proportional Cox models and expressed as hazard ratios (HRs).

RESULTS

Among 841 screened patients, 546 patients (median [IQR] age, 67.4 [59.3-73.1] years; 414 [75.8%] men) were randomized between standard dexamethasone (276 patients, including 37 patients who received placebo) or high-dose dexamethasone (270 patients). Of these, 333 patients were randomized among o2SC (109 patients, including 56 receiving standard dexamethasone), CPAP (109 patients, including 57 receiving standard dexamethasone), and HFNo2 (115 patients, including 56 receiving standard dexamethasone). There was no difference in 60-day mortality between standard and high-dose dexamethasone groups (HR, 0.96 [95% CI, 0.69-1.33]; P = .79). There was no significant difference for the cumulative incidence of IMV criteria at day 28 among o2 support groups (o2SC vs CPAP: HR, 1.08 [95% CI, 0.71-1.63]; o2SC vs HFNo2: HR, 1.04 [95% CI, 0.69-1.55]) or 60-day mortality (o2SC vs CPAP: HR, 0.97 [95% CI, 0.58-1.61; o2SC vs HFNo2: HR, 0.89 [95% CI, 0.53-1.47]). Interactions between interventions were not significant.

CONCLUSIONS AND RELEVANCE

In this randomized clinical trial among ICU patients with COVID-19-related AHRF, high-dose dexamethasone did not significantly improve 60-day survival. The oxygenation strategies in patients who were not initially receiving IMV did not significantly modify 28-day risk of IMV requirement.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04344730; EudraCT: 2020-001457-43.

Deployment of Tele-ICU Respiratory Therapy and the Creation of an eRT Service Line

Penn Medicine launched a 24-7 telemedicine respiratory therapist (eRT) service as part of its tele–critical care medicine (tele-CCM) service serving seven hospitals and more than 320 critical care beds. Service line interventions were focused on protocolized evidence-based practices, safety, documentation compliance, and urgent emergent ad hoc clinical needs. Concomitantly, the eRTs were available to respond to urgent and emergent interventions on the basis of the clinical bedside situation. Their activity was triggered by Penn E-lert staff (serving the tele-ICUs), bedside staff, algorithmic trigger software, or the eRT’s own review of a patient’s clinical condition. A standardized data collection was deployed to gather information about the interventions. The value of the eRT service was defined in terms of estimated lives saved by implementing the standards of care earlier than the bedside staff would or acute respiratory distress syndrome (ARDS) algorithmic trigger and by intervening during emergent and urgent clinical request, improving care delivery, and complying with best clinical practices, and by the time freed for onsite staff to perform other duties. Between May 2020 and August 2021, eRTs registered 31,609 activities; 97.8% of interventions were related to the routine established workflows, while 1.9% were urgent and 0.3% emergent. In 51.2% of all eRT accomplished activities, no communication with other staff was needed. When communication did take place, eRTs connected with the bedside respiratory therapist in 36.7% of interactions, followed by house staff (7.2%), advanced practice providers (5.2%), and registered nurses (1.6%). The eRTs communicated via phone (81.4%), asynchronous text platform (16%), or tele-CCM software (1.4%). While prompted by staffing, safety, and logistics challenges during a Covid-19 surge, the resulting eRT service line has been well received and has become a part of the standard of care. Overall efficiency of respiratory care service delivery was increased as Penn retained staff and increased the flexibility of bedside therapists. Furthermore, the eRT service detected unfavorable practice patterns in ARDS treatment and intervened before the ARDS algorithmic trigger was activated or acted upon. Some of the tasks can be accomplished by the eRT in a shorter amount of time than it would take bedside staff. In addition, the remote staffing reduced personal protective equipment utilization. All of these gains translated into postpandemic time savings. Penn’s experience shows that the eRT care model can be transformed into a system-valued proposition and retained with sustained benefit beyond the pandemic surge.

Awake prone position reduces work of breathing in patients with COVID-19 ARDS supported by CPAP

Background

The use of awake prone position concomitant to non-invasive mechanical ventilation in acute respiratory distress syndrome (ARDS) secondary to COVID-19 has shown to improve gas exchange, whereas its effect on the work of breathing remain unclear. The objective of this study was to evaluate the effects of awake prone position during helmet continuous positive airway pressure (CPAP) ventilation on inspiratory effort, gas exchange and comfort of breathing.

Methods

Forty consecutive patients presenting with ARDS due to COVID-19 were prospectively enrolled. Gas exchange, esophageal pressure swing (ΔPes), dynamic transpulmonary pressure (dTPP), modified pressure time product (mPTP), work of breathing (WOB) and comfort of breathing, were recorded on supine position and after 3 h on prone position.

Results

The median applied PEEP with helmet CPAP was 10 [8–10] cmH₂O. The PaO₂/FiO₂ was higher in prone compared to supine position (Supine: 166 [136–224] mmHg, Prone: 314 [232–398] mmHg, p < 0.001). Respiratory rate and minute ventilation decreased from supine to prone position from 20 [17–24] to 17 [15–19] b/min (p < 0.001) and from 8.6 [7.3–10.6] to 7.7 [6.6–8.6] L/min (p < 0.001), respectively. Prone position did not reduce ΔPes (Supine: − 7 [− 9 to − 5] cmH₂O, Prone: − 6 [− 9 to − 5] cmH₂O, p = 0.31) and dTPP (Supine: 17 [14–19] cmH₂O, Prone: 16 [14–18] cmH₂O, p = 0.34). Conversely, mPTP and WOB decreased from 152 [104–197] to 118 [90–150] cmH₂O/min (p < 0.001) and from 146 [120–185] to 114 [95–151] cmH₂O L/min (p < 0.001), respectively. Twenty-six (65%) patients experienced a reduction in WOB of more than 10%. The overall sensation of dyspnea was lower in prone position (p = 0.005).

Conclusions

Awake prone position with helmet CPAP enables a reduction in the work of breathing and an improvement in oxygenation in COVID-19-associated ARDS.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13613-021-00967-6.

Anti-Inflammatory Effects of Immunostimulation in Patients with COVID-19 Pneumonia

Background: The effects of immunomodulators in patients with Coronavirus Disease 2019 (COVID-19) pneumonia are still unknown. We investigated the cellular inflammatory and molecular changes in response to standard-of-care + pidotimod (PDT) and explored the possible association with blood biomarkers of disease severity. Methods: Clinical characteristics and outcomes, neutrophil-to-lymphocyte ratio (NLR), plasma and cell supernatant chemokines, and gene expression patterns after SARS-CoV-2 and influenza (FLU) virus in vitro stimulation were assessed in 16 patients with mild-moderate COVID-19 pneumonia, treated with standard of care and PDT 800 mg twice daily (PDT group), and measured at admission, 7 (T1), and 12 (T2) days after therapy initiation. Clinical outcomes and NLR were compared with age-matched historical controls not exposed to PDT. Results: Hospital stay, in-hospital mortality, and intubation rate did not differ between groups. At T1, NLR was 2.9 (1.7–4.6) in the PDT group and 5.5 (3.4–7.1) in controls (p = 0.037). In the PDT group, eotaxin and IL-4 plasma concentrations progressively increased (p < 0.05). Upon SARS-CoV-2 and FLU-specific stimulation, IFN-γ was upregulated (p < 0.05), while at genetic transcription level, Pathogen Recognition Receptors (TRLs) were upregulated, especially in FLU-stimulated conditions. Conclusions: Immunomodulation exerted by PDT and systemic corticosteroids may foster a restoration in the innate response to the viral infection. These results should be confirmed in larger RCTs.