Management of COVID-19 Respiratory Distress

In early 2022, there was a sudden surge of patients infected by the Omicron variant of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in Hong Kong (HK), resulting in 9,163 deaths as of 29 May 2022. Many of the local population had not been vaccinated before this wave. The number of patients who developed coronavirus disease 2019 (COVID-19) related respiratory failure outnumbered the capacity of intensive care unit (ICU) beds. Some of these patients had to be supported with high flow nasal cannula (HFNC) therapy outside ICU setting. HK was in crisis situation. The primary objective of this study is to assess the 28-day mortality of this group of patients. The secondary objective is to explore any predictors of non-survivors to help clinical decision-making in future crisis. This is a retrospective observational study of patients suffering from COVID-19 related respiratory failure who received HFNC therapy in general medical wards of two hospitals during the period of 17 Mar to 30 Apr 2022. Survival and risk factors were reviewed. Forty-nine patients were recruited. Twenty-six patients (53%) survived at 28-day after initiation of HFNC support. Three clinical parameters were found to be significantly associated with mortality at 28-day: (I) SpO2/FiO2 (SF) ratio <160 at 48 hours; (II) SF ratio <191 at 72 hours; (III) serial SF ratio at 48 or 72 hours showing no improvement over that at the time of initiation of HFNC therapy. Use of HFNC outside ICU setting showed benefit to patients suffering from COVID-19 related acute hypoxemic respiratory failure (AHRF). Serial SF ratio monitoring at 48 and 72 hours after therapy initiation might serve as predictors of outcome and thus guide clinical decision-making for medical resource allocation in outbreak situation.

Predictors of poor outcome in tocilizumab treated patients with Sars-CoV-2 related severe respiratory failure: A multicentre real world study

Background Lung transplantation (LT) is a potentially life-saving treatment option for COVID-19 related irreversible respiratory failure. Early outcomes for 1-year survival and graft failure rates among LT recipients (LTr) for COVID-19 related respiratory failure is similar to LTr for non-COVID etiologies. However, the infectious, real-world analysis of complications following LT among LTr for COVID-19 related respiratory failure in comparison to LTr in COVID-19 unrelated respiratory failure has not been described. Our objective was to compare the post-LT infectious complications among LTr for COVID-19 related and unrelated respiratory failure. Methods We analyzed all consecutive LT done at Henry Ford Health System from January 2020 to October 2023. All patients received standard antimicrobial prophylaxis. Demographic data was obtained. The primary outcome was the rate of any infectious complication within one year from transplantation. Secondary outcomes were rates of specific infections, time to infection, and all-cause mortality at 30 days, 90 days, and 1- year. Results A total of 98 lung transplantations were done at our center from January 2020 to October 2023. COVID-19 related LTr accounted for 11% of transplants. Median time of follow up was 365 days (187-365). COVID-19 related LTr were younger (median 53 vs. 64 years [p 0.02]) and predominantly white race (p &amp;lt; 0.01). Comorbidities amongst both groups were similar. Rates of post-LTr infectious complications were similar among the two groups, 66% overall. Time to first infection was shorter in the COVID-19 related LTr cohort, however this did not reach significance. Pleuropulmonary infections predominated overall (47%). All-cause post-LT mortality was similar in both groups (Table 1). Conclusion Patients receiving LT for COVID-19 related respiratory failure have similar, high rates of infectious complications compared to patients with non-COVID-19 related etiologies, but mortality remains low. LT for COVID-19 related respiratory failure is an acceptable modality of treatment. Disclosures Mayur Ramesh, MD, AstraZeneca: Advisor/Consultant|Moderna: Advisor/Consultant|Pfizer: Advisor/Consultant

Non-invasive respiratory support paths in hospitalized patients with COVID-19: proposal of an algorithm

COVID-19 related Acute Respiratory Failure, may be successfully treated with Conventional Oxygen therapy, High Flow Nasal Cannula, Continuous Positive Airway Pressure or Bi-level Positive-Pressure ventilation. Despite the accumulated data in favor of the use of different Non-invasive Respiratory therapies in COVID-19 related Acute Respiratory Failure, it is not fully understood when start, escalate and de-escalate the best respiratory supportive option for the different timing of the disease. Based on the current published experience with Non-invasive Respiratory therapies in COVID-19 related Acute Respiratory Failure, we propose an algorithm in deciding when to start, when to stop and when to wean different NIRT. This strategy may help clinicians in better choosing NIRT during this second COVID-19 wave and beyond.

Metformin in acute respiratory distress syndrome: An opinion

Non-invasive oxygenation strategies for respiratory failure with COVID-19: A concise narrative review of literature in pre and mid-COVID-19 era

<b>Background:</b> Failing autoregulation of pulmonary vessels and higher shunt have been described in Covid-19 related Acute respiratory failure (ARF). The aim was to investigate shunt fraction in patients with Covid-19-ARF compared to patients with other causes of ARF. <b>Methods:</b> Observational study of hospitalized patients with Covid-19-ARF and other causes of ARF at Papa Giovanni XXIII Hospital, Bergamo, Italy between June 2020 and November 2021. Shunt fraction was measured by a non-invasive system during spontaneous breathing (Beacon®Caresystem). <b>Results:</b> We enrolled 51 adult patients (8 female), mean age (±SD) 65±13 years and mean BMI 28,3±5,3 Kg/m2. Covid-19-ARF patients represented 71% (36/51). Community acquired pneumonia was the most common cause of other ARF (11/15). No differences in terms of age and BMI were described between the two groups. Pulmonary gas exchange impairment was similar, median PaO2/FIO2 ratio was 254 [IQR 162,297] in Covid-19-ARF and 269 [IQR 201,296] in other causes of ARF patients (p=0.41). Nevertheless, mean shunt fraction resulted significantly increased in Covid-19-ARF (18±6%) than other causes of ARF patients (12±9%; p=0.03) Fig. 1. <b>Conclusion:</b> Shunt fraction appears to be increased in Covid-19-ARF if compared to patients with other causes of ARF. However, this is the first study proposing this non-invasive method to measure shunt fraction in ARF and further investigations are needed to validate this technique.

Extracorporeal membrane oxygenation in pregnancy: a bridge to delivery and pulmonary recovery for COVID-19–related severe respiratory failure

Successful Treatment of COVID-19 Patient on ECMO Using Mesenchymal Stromal Cells (MSC)-Derived Exosomes: A Case Report

COVID-19 is the infection caused by the new coronavirus. Specific treatment for COVID-19 has not been established, yet. It is important to determine the disease severity of the patients at the first admission. Therefore, the exploration of biomarkers is deemed necessary. We aimed to assess the diagnostic and early prognostic value of CRP and LDH levels in possible COVID-19 patients presenting with a severe clinical picture. We evaluated the correlations of relevant routine laboratory test results with disease severity in COVID-19 patients admitted to our infectious diseases clinic. Patients were divided into severe and non-severe disease groups based on clinical findings, oxygen saturation levels in the arterial blood, biochemical test results, and radiological findings. Differences in the findings between the two disease severity groups were examined to determine potential biomarkers. Median age and the CRP and LDH levels in the severe disease group were statistically significantly higher compared to the nonsevere group (p < 0.0001). No other parameters statistically significant differences have been observed between the two groups (P > 0.05). CRP and LDH levels were positively correlated with lung lesions in early-stage COVID-19, potentially reflecting disease severity. Because LDH and CRP levels can potentially reflect the pulmonary function, they can be potential predictors of COVID-19- related respiratory failure. For avoiding poor prognosis; LDH and CRP should be considered as potential predictors for identifying the need for thoracic CT scans, close monitoring of pulmonary function, and aggressive supportive therapy early in the course of COVID-19.

Effect of corticosteroids on survival of children with acquired immunodeficiency syndrome and Pneumocystis carinii -related respiratory failure

The COVID19 pandemic has pushed healthcare workers to utilize available therapeutics, often with limited evidence. Theoretically, IL6 inhibitors could help to stop or reverse the damage caused by COVID19 cytokine storm. Published evidence from the United States is conflicting and is largely from academic institutions and nonminority populations. This study assessed the clinical utility of open-label tocilizumab in two multiethnic community hospitals in Queens, NY.Tocilizumab (8mg/kg) was given to 114 patients for treatment of COVID19- related respiratory failure between April 4 and May 19 2020 (96% received 1 dose). A retrospective cohort study was performed to determine 28-day clinical success, defined as achieving a score of 1 using a 6-point scale (1=no O2 requirement or discharged home on 2L/min;2=low-flow O2 in hospital ≤6L/min;3=O2 >6 to ≤15L/min;4=high-flow, CPAP, or BiPAP;5=mechanically ventilated (MV);6=expired). The decision to administer tocilizumab was made by a committee based on unstable or worsening respiratory status. Mean patient age was 60 years (SD=11);77(67%) were male. 25% were Asian, 23% black (31% black Hispanic), 36% white (73% white Hispanic), and 14% other. A majority of patients had at least 1 significant comorbidity, including HTN 56%, DM 40%, HLD 43%, and COPD/asthma 16%. Median days of symptoms at dose was 14(IQR 10-19);SpO2 on RA at admission was 82%(IQR 67-88%). Baseline status by ordinal scale was as follows: 2= 9(8%);3=33(29%);4=38(33%);5=34(30%) (IQR 1-2 days on vent). Median CRP=19.9, d-dimer=1658, ferritin=593, and LDH=1561. 28-day success was achieved in 35(31%) patients;62(55%) patients expired or were MV on day 28. Of patients who were on high-flow, CPAP, BiPAP or MV at baseline, 80% expired or were on MV on day 28. Estimated mortality in all hospitalized patients during the time frame at these hospitals was 36%. No significant differences were seen in labs, comorbidities or age between patients who did and did not have clinical success. Higher baseline ordinal scale score was predictive of mortality.Tocilizumab provided little to no clinical utility, especially in those with high oxygenation needs at time of dosing (success rate <20%). The main limitation is lack of a control group;however mortality was strikingly high. This in part may be due to the demographic and clinical characteristics of our sample.

A Matched Survival Analysis of Lung Transplant Recipients With Coronavirus Disease 2019–Related Respiratory Failure

Background: Patients with severe COVID-19 related respiratory failure may require veno-venous extracorporeal membrane oxygenation (VV ECMO). After decannulation, patients on VV ECMO have historically had high percentages of cannula-associated deep vein thrombosis (CaDVT). Due to their hypercoagulable state and prolonged course on VV ECMO, we hypothesized that patients with COVID-19 would experience a higher rate of CaDVT when compared to their non-COVID-19 counterparts. We also described the association between location and size of cannula in the development of CaDVTs. Methods: This was a single center retrospective review of patients ≥ 18 years old who were treated with VV ECMO and decannulated from January 1, 2014, to January 10, 2022. Patients who were placed on VV ECMO due to trauma and patients who were cannulated for veno-arterial ECMO were excluded. Patients were managed in a dedicated Lung Rescue Unit and anticoagulated with a heparin infusion at a goal partial thromboplastin time (aPTT) of 45-55 or 60-80 depending on the presence of clotting complications. Post-decannulation venous duplexes were performed 24 hours after decannulation and if positive for DVT, performed again in 2 weeks. Univariate and multivariate analyses were conducted to analyze our primary outcome of the development of CaDVT. Results: A total of 291 patients met our inclusion criteria: 76 COVID-19 VV ECMO patients and 215 non-COVID-19 VV ECMO patients. Decannulated COVID-19 VV ECMO patients had a significantly higher body mass index (BMI) (35.8, 32.9, p= 0.03) and length of ECMO run (hours) (660, 312, p< 0.001) than their non-COVID-19 counterparts. Most decannulated patients in both groups received post-decannulation duplexes (96%, 99%, p= 0.45). COVID-19 and non-COVID-19 patients decannulated from VV ECMO both experienced high incidences of CaDVT on initial post-decannulation ultrasound (95%, 88%, p= 0.13). COVID-19 patients were more likely to have multiple CaDVTs (32%, 11%, p< 0.001). Patients with COVID-19 experienced a higher rate of right common femoral CaDVT (47%, 17%, p< 0.001) and a higher percentage of 25 French drainage cannula CaDVT (48%, 18%, p< 0.001). COVID-19 VV ECMO patients had a significantly higher incidence of persistent CaDVT on repeat ultrasound (78%, 56%, p= 0.03). A logistic regression was performed with all decannulated patients. Age, BMI, hours on ECMO, COVID-19 status, and size and location of ECMO cannulas did not predict the presence of DVT. Conclusion: Both COVID-19 and non-COVID-19 VV ECMO patients had high rates of CaDVTs. The utilization of VV ECMO in COVID-19 respiratory failure was associated with a higher incidence of CaDVTs on repeat ultrasound as compared to patients with non-COVID-19 related respiratory failure. Regular post-decannulation screening, treatment, and follow up imaging should be performed. Further investigation into the effect of anticoagulation strategy is needed.