Implications of Obesity for the Management of Severe Coronavirus Disease 2019 Pneumonia

D-dimer levels in non-COVID-19 ARDS and COVID-19 ARDS patients: A systematic review with meta-analysis

BACKGROUND

Hypercoagulability and thrombo-inflammation are the main reasons for death in COVID-19 patients. It is unclear whether there is a difference between D-dimer levels in patients without or with COVID-19 acute respiratory distress syndrome (ARDS).

METHODS

We searched PubMed, EMBASE, and ClinicalTrails.gov databases looking for studies reporting D-dimer levels in patients without or with COVID-19 ARDS. Secondary endpoints included length of hospital stay, and mortality data at the longest follow-up available.

RESULTS

We included 12 retrospective and 3 prospective studies with overall 2,828 patients, of whom 1,404 (49.6%) had non-COVID-19 ARDS and 1,424 had COVID-19 ARDS. D-dimer levels were not significantly higher in non-COVID-19 ARDS than in COVID-19 ARDS patients (mean 7.65 mg/L vs. mean 6.20 mg/L MD 0.88 [CI: -0.61 to 2.38] p = 0.25; I² = 85%) while the length of hospital stay was shorter (non-COVID-19 mean 37.4 days vs. COVID-19 mean 48.5 days, MD -10.92 [CI: -16.71 to -5.14] p < 0.001; I² = 44%). No difference in mortality was observed: non-COVID-19 ARDS 418/1167 (35.8%) vs. COVID-19 ARDS 467/1201 (38.8%).

CONCLUSIONS

We found no difference in the mean D-dimer levels between non-COVID-19 ARDS and COVID-19 ARDS patients.

Association between trans fatty acids and COVID-19: A multivariate Mendelian randomization study

Traditional observational studies have suggested a potential association between trans fatty acids (TFAs), which are considered to be health-damaging fatty acids, and coronavirus disease 2019 (COVID-19). However, whether there is a causal relationship between them is currently unclear. We aimed to investigate the causal link between genetically determined TFAs and COVID-19. We performed univariate and multivariate Mendelian randomization (MR) studies using summary statistics from the European Pedigree TFAs (n = 8013), COVID-19 susceptibility (n = 159 840), COVID-19 hospitalization (n = 44 986), and COVID-19 severity (n = 18 152) genome-wide association studies (GWAS). The inverse variance weighted (IVW) method was used as the primary MR analysis, and several other methods were used as supplements. In univariate MR analysis, higher levels of circulating trans, cis-18:2 TFAs were positively associated with a higher COVID-19 hospitalization rate (p < 0.0033; odds ratio [OR] = 1.637; 95% confidence interval [CI]: 1.116-2.401) and COVID-19 severity (p < 0.0033; OR = 2.575; 95% CI: 1.412-4.698). Furthermore, in multivariate MR analysis, trans, cis-18:2 had an independent and significant causal association with a higher COVID-19 hospitalization rate (p = 0.00044; OR = 1.862; 95% CI = 1.316-2.636) and COVID-19 severity (p = 0.0016; OR = 2.268; 95% CI = 1.361-3.779) after the five TFAs were adjusted for each other. Together, our findings provide evidence that trans, cis-18:2 TFAs have an independent and robust causal effect on COVID-19 hospitalization and severity.

Respiratory system mechanics, gas exchange, and outcomes in mechanically ventilated patients with COVID-19-related acute respiratory distress syndrome: a systematic review and meta-analysis

The association of respiratory mechanics, particularly respiratory system static compliance (C_RS), with severity of hypoxaemia in patients with COVID-19-related acute respiratory distress syndrome (ARDS) has been widely debated, with some studies reporting distinct ARDS phenotypes based on C_RS. Ascertaining whether such phenotypes exist is important, because they might indicate the need for ventilation strategies that differ from those used in patients with ARDS due to other causes. In a systematic review and meta-analysis of studies published between Dec 1, 2019, and March 14, 2022, we evaluated respiratory system mechanics, ventilator parameters, gas exchange parameters, and clinical outcomes in patients with COVID-19-related ARDS. Among 11 356 patients in 37 studies, mean reported C_RS, measured close to the time of endotracheal intubation, was 35·8 mL/cm H₂O (95% CI 33·9-37·8; I²=96·9%, τ²=32·6). Pooled mean C_RS was normally distributed. Increasing ARDS severity (assessed by PaO₂/FiO₂ ratio as mild, moderate, or severe) was associated with decreasing C_RS. We found no evidence for distinct C_RS-based clinical phenotypes in patients with COVID-19-related ARDS, and we therefore conclude that no change in conventional lung-protective ventilation strategies is warranted. Future studies should explore the personalisation of mechanical ventilation strategies according to factors including respiratory system mechanics and haemodynamic status in patients with ARDS.

Nutritional management of individuals with obesity and COVID-19: ESPEN expert statements and practical guidance

The COVID-19 pandemics has created unprecedented challenges and threats to patients and healthcare systems worldwide. Acute respiratory complications that require intensive care unit (ICU) management are a major cause of morbidity and mortality in COVID-19 patients. Among other important risk factors for severe COVID-19 outcomes, obesity has emerged along with undernutrition-malnutrition as a strong predictor of disease risk and severity. Obesity-related excessive body fat may lead to respiratory, metabolic and immune derangements potentially favoring the onset of COVID-19 complications. In addition, patients with obesity may be at risk for loss of skeletal muscle mass, reflecting a state of hidden malnutrition with a strong negative health impact in all clinical settings. Also importantly, obesity is commonly associated with micronutrient deficiencies that directly influence immune function and infection risk. Finally, the pandemic-related lockdown, deleterious lifestyle changes and other numerous psychosocial consequences may worsen eating behaviors, sedentarity, body weight regulation, ultimately leading to further increments of obesity-associated metabolic complications with loss of skeletal muscle mass and higher non-communicable disease risk. Therefore, prevention, diagnosis and treatment of malnutrition and micronutrient deficiencies should be routinely included in the management of COVID-19 patients in the presence of obesity; lockdown-induced health risks should also be specifically monitored and prevented in this population. In the current document, the European Society for Clinical Nutrition and Metabolism (ESPEN) aims at providing clinical practice guidance for nutritional management of COVID-19 patients with obesity in various clinical settings.

The impact of obesity on the outcome of severe SARS-CoV-2 ARDS in a high volume ECMO centre: ECMO and corticosteroids support the obesity paradox

PURPOSE

The aim was to verify the impact of obesity on the long-term outcome of patients with severe SARS-CoV-2 ARDS.

MATERIALS AND METHODS

The retrospective study included patients admitted to the high-volume ECMO centre between March 2020 and March 2022. The impact of body mass index (BMI), co-morbidities and therapeutic measures on the short and 90-day outcomes was analysed.

RESULTS

292 patients were included, of whom 119(40.8%) were treated with veno-venous ECMO cannulated mostly (73%) in a local hospital. 58.5% were obese (64.7% on ECMO), the ECMO was most frequent in BMI > 40(49%). The ICU mortality (36.8% for obese vs 33.9% for the non-obese, p = 0.58) was related to ECMO only for the non-obese (p = 0.04). The 90-day mortalities (48.5% obese vs 45.5% non-obese, p = 0.603) of the ECMO and non-ECMO patients were not significantly influenced by BMI (p = 0.47, p = 0.771, respectively). The obesity associated risk factors for adverse outcome were age <50 (RR 2.14) and history of chronic immunosuppressive therapy (RR 2.11, p = 0.009). The higher dosage of steroids (RR 0.57, p = 0.05) associated with a better outcome.

CONCLUSIONS

The high incidence of obesity was not associated with worse short and long-term outcomes. ECMO in obese patients together with the use of steroids in the later stage of ARDS may improve survival.

Obesity and Coronavirus Disease 2019

The coronavirus disease 2019 (COVID-19) pandemic has brought severe challenges to global public health. Many studies have shown that obesity plays a vital role in the occurrence and development of COVID-19. Obesity exacerbates COVID-19, leading to increased intensive care unit hospitalization rate, high demand for invasive mechanical ventilation, and high mortality. The mechanisms of interaction between obesity and COVID-19 involve inflammation, immune response, changes in pulmonary dynamics, disruptions of receptor ligands, and dysfunction of endothelial cells. Therefore, for obese patients with COVID-19, the degree of obesity and related comorbidities should be evaluated. Treatment methods such as administration of anticoagulants and anti-inflammatory drugs like glucocorticoids and airway management should be actively initiated. We should also pay attention to long-term prognosis and vaccine immunity and actively address the physical and psychological problems caused by longterm staying-at-home during the pandemic. The present study summarized the research to investigate the role of obesity in the incidence and progression of COVID-19 and the psychosocial impact and treatment options for obese patients with COVID-19, to guide the understanding and management of the disease.

Sequential treatment of severe pneumonia with respiratory failure and its influence on respiratory mechanical parameters and hemodynamics

BACKGROUND

The pathophysiological characteristics of severe pneumonia complicated by respiratory failure comprise pulmonary parenchymal changes leading to ventilation imbalance, alveolar capillary injury, pulmonary edema, refractory hypoxemia, and reduced lung compliance. Prolonged hypoxia can cause acid-base balance disorder, peripheral circulatory failure, blood-pressure reduction, arrhythmia, and other adverse consequences.

AIM

To investigate sequential mechanical ventilation’s effect on severe pneumonia complicated by respiratory failure.

METHODS

We selected 108 patients with severe pneumonia complicated by respiratory failure who underwent mechanical ventilation between January 2018 and September 2020 at the Luhe Hospital’s Intensive Care Unit and divided them into sequential and regular groups according to a randomized trial, with each group comprising 54 patients. The sequential group received invasive and non-invasive sequential mechanical ventilation, whereas the regular group received invasive mechanical ventilation. Blood-gas parameters, hemodynamic parameters, respiratory mechanical parameters, inflammatory factors, and treatment outcomes were compared between the two groups before and after mechanical-ventilation treatment.

RESULTS

The arterial oxygen partial pressure and stroke volume variation values of the sequential group at 24, 48, and 72 h of treatment were higher than those of the conventional group (P < 0.05). The carbon dioxide partial pressure value of the sequential group at 72 h of treatment and the Raw value of the treatment group at 24 and 48 h were lower than those of the conventional group (P < 0.05). The pH value of the sequential group at 24 and 72 h of treatment, the central venous pressure value of the treatment at 24 h, and the Cst value of the treatment at 24 and 48 h were higher than those of the conventional group (P < 0.05). The tidal volume in the sequential group at 24 h of treatment was higher than that in the conventional group (P < 0.05), the measured values of interleukin-6 and tumor necrosis factor-α in the sequential group at 72 h of treatment were lower than those in the conventional group (P < 0.05), and the total time of mechanical ventilation in the sequential group was shorter than that in the conventional group, with a statistically significant difference (P < 0.05).

CONCLUSION

Treating severe pneumonia complicated by respiratory failure with sequential mechanical ventilation is more effective in improving respiratory system compliance, reducing inflammatory response, maintaining hemodynamic stability, and improving patient blood-gas levels; however, from this study’s perspective, it cannot reduce patient mortality.

Early Intensive Physical Rehabilitation Combined with a Protocolized Decannulation Process in Tracheostomized Survivors from Severe COVID-19 Pneumonia with Chronic Critical Illness

(1) Background: Intensive care unit (ICU) survivors from severe COVID-19 acute respiratory distress syndrome (CARDS) with chronic critical illness (CCI) may be considered vast resource consumers with a poor prognosis. We hypothesized that a holistic approach combining an early intensive rehabilitation with a protocol of difficult weaning would improve patient outcomes (2) Methods: A single-center retrospective study in a five-bed post-ICU weaning and intensive rehabilitation center with a dedicated fitness room specifically equipped to safely deliver physical activity sessions in frail patients with CCI. (3) Results: Among 502 CARDS patients admitted to the ICU from March 2020 to March 2022, 50 consecutive tracheostomized patients were included in the program. After a median of 39 ICU days, 25 days of rehabilitation were needed to restore patients’ autonomy (ADL, from 0 to 6; p < 0.001), to significantly improve their aerobic capacity (6-min walking test distance, from 0 to 253 m; p < 0.001) and to reduce patients’ vulnerability (frailty score, from 7 to 3; p < 0.001) and hospital anxiety and depression scale (HADS, from 18 to 10; p < 0.001). Forty-eight decannulated patients (96%) were discharged home. (4) Conclusions: A protocolized weaning strategy combined with early intensive rehabilitation in a dedicated specialized center boosted the physical and mental recovery.

Respiratory and nonrespiratory COVID-19 complications in patients with obesity: recent developments

This narrative review summarizes recent reports to provide an updated understanding of the multiorgan effects of SARS-CoV-2 infection in obese individuals. A PubMed search of 528 primary articles was performed, with inclusion based on novelty, relevance and redundancy. Obesity confers an increased risk for hospitalization, intensive care unit admission, severe pneumonia, intubation and acute kidney injury in COVID-19 patients. Obesity is also associated with higher levels of inflammatory and thrombotic markers. However, the associations between obesity and mortality or cardiac injury in COVID-19 patients remain unclear. Obesity is a risk factor for several respiratory and nonrespiratory COVID-19 complications. Future work is needed to further explore these relationships and optimize the management of obese COVID-19 patients.

The negative impact of obesity on the occurrence and prognosis of the 2019 novel coronavirus (COVID-19) disease: a systematic review and meta-analysis

PURPOSE

The 2019 novel coronavirus (COVID-19) is an emerging pandemic, with a disease course varying from asymptomatic infection to critical disease resulting to death. Recognition of prognostic factors is essential because of its growing prevalence and high clinical costs. This meta-analysis aimed to evaluate the global prevalence of obesity in COVID-19 patients and to investigate whether obesity is a risk factor for the COVID-19, COVID-19 severity, and its poor clinical outcomes including hospitalization, intensive care unit (ICU) admission, need for mechanical ventilation, and mortality.

METHODS

The study protocol was registered in PROSPERO (CRD42020203386). A systematic search of Scopus, Medline, and Web of Sciences was conducted from 31 December 2019 to 1 June 2020 to find pertinent studies. After selection, 54 studies from 10 different countries were included in the quantitative analyses. Pooled odds ratios (OR) with 95% confidence intervals (CIs) were calculated to assess the associations.

RESULTS

The prevalence of obesity was 33% (95% CI 30.0%-35.0%) among patients with COVID-19. Obesity was significantly associated with susceptibility to COVID-19 (OR = 2.42, 95% CI 1.58-3.70; moderate certainty) and COVID-19 severity (OR = 1.62, 95% CI 1.48-1.76; low certainty). Furthermore, obesity was a significant risk factor for hospitalization (OR = 1.75, 95% CI 1.47-2.09; very low certainty), mechanical ventilation (OR = 2.24, 95% CI 1.70-2.94; low certainty), intensive care unit (ICU) admission (OR = 1.75, 95% CI 1.38-2.22; low certainty), and death (OR = 1.23, 95% CI 1.06-1.41; low certainty) in COVID-19 patients. In the subgroup analyses, these associations were supported by the majority of subgroups.

CONCLUSION

Obesity is associated with COVID-19, need for hospitalization, mechanical ventilation, ICU admission, and death due to COVID-19.

LEVEL OF EVIDENCE

Level I, systematic reviews and meta-analyses.

Impact of prior bariatric surgery on risk and severity of COVID-19 infection: A meta-analysis of observational studies

BACKGROUND

The association of prior bariatric surgery (BS) with infection rate and prognosis of coronavirus disease 2019 (COVID-19) remains unclear. We conducted a meta-analysis of observational studies to address this issue.

METHODS

We searched databases including MEDLINE, Embase, and CENTRAL from inception to May, 2022. The primary outcome was risk of mortality, while secondary outcomes included risk of hospital/intensive care unit (ICU) admission, mechanical ventilation, acute kidney injury (AKI), and infection rate.

RESULTS

Eleven studies involving 151,475 patients were analyzed. Meta-analysis showed lower risks of mortality [odd ratio (OR)= 0.42, 95% CI: 0.27-0.65, p < 0.001, I² = 67%; nine studies; 151,113 patients, certainty of evidence (COE):moderate], hospital admission (OR=0.56, 95% CI: 0.36-0.85, p = 0.007, I² =74.6%; seven studies; 17,810 patients; COE:low), ICU admission (OR=0.5, 95% CI: 0.37-0.67, p < 0.001, I² =0%; six studies; 17,496 patients, COE:moderate), mechanical ventilation (OR=0.52, 95% CI: 0.37-0.72, p < 0.001, I² =57.1%; seven studies; 137,992 patients, COE:moderate) in patients with prior BS (BS group) than those with obesity without surgical treatment (non-BS group). There was no difference in risk of AKI (OR=0.74, 95% CI: 0.41-1.32, p = 0.304, I² =83.6%; four studies; 129,562 patients, COE: very low) and infection rate (OR=1.05, 95% CI: 0.89-1.22, p = 0.572, I² =0%; four studies; 12,633 patients, COE:low) between the two groups. Subgroup analysis from matched cohort studies demonstrated associations of prior BS with lower risks of mortality, ICU admission, mechanical ventilation, and AKI.

CONCLUSION

Our results showed a correlation between prior BS and less severe COVID-19, which warrants further investigations to verify.

Nutritional parameters and outcomes in patients admitted to intensive care with COVID-19: a retrospective single-centre service evaluation

COVID-19 is an inflammatory syndrome caused by novel coronavirus SARS-CoV-2. Symptoms range from mild infection to severe acute respiratory distress syndrome (ARDS) requiring ventilation and intensive care. At the time of data collection, UK cases were around 300 000 with a fatality rate of 13% necessitating over 10 000 critical care admissions; now there have been over 4 million cases. Nutrition is important to immune function and influences metabolic risk factors such as obesity and glycaemic control, as well as recovery from acute illnesses. Poor nutritional status is associated with worse outcomes in ARDS and viral infections, yet limited research has assessed pre-morbid nutritional status and outcomes in patients critically unwell with COVID-19.

OBJECTIVES

Investigate the effect of body mass index (BMI), glycaemic control and vitamin D status on outcomes in adult patients with COVID-19 admitted to an intensive care unit (ICU).

METHODS

Retrospective review of all patients admitted to a central London ICU between March and May 2020 with confirmed COVID-19. Electronic patient records data were analysed for patient demographics; comorbidities; admission BMI; and serum vitamin D, zinc, selenium and haemoglobin A1c (HbA1c) concentrations. Serum vitamin D and HbA1c were measured on admission, or within 1 month of admission to ICU. Primary outcome of interest was mortality. Secondary outcomes included time intubated, ICU stay duration and ICU-related morbidity.

RESULTS

Seventy-two patients; 54 (75%) men, mean age 57.1 (±9.8) years, were included. Overall, mortality was 24 (33%). No significant association with mortality was observed across BMI categories. In the survival arm admission, HbA1c (mmol/mol) was lower, 50.2 vs 60.8, but this was not statistically significant. Vitamin D status did not significantly associate with mortality (p=0.131). However, 32% of patients with low vitamin D (<25 IU/L) died, compared with 13% of patients with vitamin D levels >26 IU/L. Serum zinc and selenium, and vitamin B12 and folate levels were measured in 46% and 26% of patients, respectively.

DISCUSSION/CONCLUSION

Increased adiposity and deranged glucose homeostasis may potentially increase risk of COVID-19 infection and severity, possibly relating to impaired lung and metabolic function, increased proinflammatory and prothrombotic mechanisms. Vitamin D deficiency may also associate with poorer outcomes and mortality, supporting a possible role of vitamin D in immune function specific to pulmonary inflammation and COVID-19 pathophysiology. There are plausible associations between raised BMI, glycaemic control, vitamin D status and poor prognosis, as seen in wider studies; however, in this service evaluation audit during the first wave of the pandemic in the UK, with a limited data set available for this analysis, the associations did not reach statistical significance. Further research is needed into specific nutritional markers influencing critical care admissions with COVID-19.

Obesity is associated with severe disease and mortality in patients with coronavirus disease 2019 (COVID-19): a meta-analysis

Background

The coronavirus disease 2019 (COVID-19) pandemic has led to global research to predict those who are at greatest risk of developing severe disease and mortality. The aim of this meta-analysis was to determine the associations between obesity and the severity of and mortality due to COVID-19.

Methods

We searched the PubMed, EMBASE, Cochrane Library and Web of Science databases for studies evaluating the associations of obesity with COVID-19.

Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using random- or fixed-effects models. Meta-regression analyses were conducted to estimate regression coefficients.

Results

Forty-six studies involving 625,153 patients were included. Compared with nonobese patients, obese patients had a significantly increased risk of infection.

(OR 2.73, 95% CI 1.53–4.87; I² = 96.8%), hospitalization (OR 1.72, 95% CI 1.55–1.92; I² = 47.4%), clinically severe disease (OR 3.81, 95% CI 1.97–7.35; I² = 57.4%), mechanical ventilation (OR 1.66, 95% CI 1.42–1.94; I² = 41.3%), intensive care unit (ICU) admission (OR 2.25, 95% CI 1.55–3.27; I² = 71.5%), and mortality (OR 1.61, 95% CI 1.29–2.01; I² = 83.1%).

Conclusion

Patients with obesity may have a greater risk of infection, hospitalization, clinically severe disease, mechanical ventilation, ICU admission, and mortality due to COVID-19. Therefore, it is important to increase awareness of these associations with obesity in COVID-19 patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-11546-6.

The Role of Nutrition in COVID-19 Susceptibility and Severity of Disease: A Systematic Review

BACKGROUND

Many nutrients have powerful immunomodulatory actions with the potential to alter susceptibility to coronavirus disease 2019 (COVID-19) infection, progression to symptoms, likelihood of severe disease, and survival.

OBJECTIVE

The aim was to review the latest evidence on how malnutrition across all its forms (under- and overnutrition and micronutrient status) may influence both susceptibility to, and progression of, COVID-19.

METHODS

We synthesized information on 13 nutrition-related components and their potential interactions with COVID-19: overweight, obesity, and diabetes; protein-energy malnutrition; anemia; vitamins A, C, D, and E; PUFAs; iron; selenium; zinc; antioxidants; and nutritional support. For each section we provide: 1) a landscape review of pertinent material; 2) a systematic search of the literature in PubMed and EMBASE databases, including a wide range of preprint servers; and 3) a screen of 6 clinical trial registries. All original research was considered, without restriction to study design, and included if it covered: 1) severe acute respiratory syndrome coronavirus (CoV) 2 (SARS-CoV-2), Middle East respiratory syndrome CoV (MERS-CoV), or SARS-CoV viruses and 2) disease susceptibility or 3) disease progression, and 4) the nutritional component of interest. Searches took place between 16 May and 11 August 2020.

RESULTS

Across the 13 searches, 2732 articles from PubMed and EMBASE, 4164 articles from the preprint servers, and 433 trials were returned. In the final narrative synthesis, we include 22 published articles, 38 preprint articles, and 79 trials.

CONCLUSIONS

Currently there is limited evidence that high-dose supplements of micronutrients will either prevent severe disease or speed up recovery. However, results of clinical trials are eagerly awaited. Given the known impacts of all forms of malnutrition on the immune system, public health strategies to reduce micronutrient deficiencies and undernutrition remain of critical importance. Furthermore, there is strong evidence that prevention of obesity and type 2 diabetes will reduce the risk of serious COVID-19 outcomes. This review is registered at PROSPERO as CRD42020186194.

High plasma concentration of non-esterified polyunsaturated fatty acids is a specific feature of severe COVID-19 pneumonia

COVID-19 pneumonia has specific features and outcomes that suggests a unique immunopathogenesis. Severe forms of COVID-19 appear to be more frequent in obese patients, but an association with metabolic disorders is not established. Here, we focused on lipoprotein metabolism in patients hospitalized for severe pneumonia, depending on COVID-19 status. Thirty-four non-COVID-19 and 27 COVID-19 patients with severe pneumonia were enrolled. Most of them required intensive care. Plasma lipid levels, lipoprotein metabolism, and clinical and biological (including plasma cytokines) features were assessed. Despite similar initial metabolic comorbidities and respiratory severity, COVID-19 patients displayed a lower acute phase response but higher plasmatic concentrations of non-esterified fatty acids (NEFAs). NEFA profiling was characterised by higher level of polyunsaturated NEFAs (mainly linoleic and arachidonic acids) in COVID-19 patients. Multivariable analysis showed that among severe pneumonia, COVID-19-associated pneumonia was associated with higher NEFAs, lower apolipoprotein E and lower high-density lipoprotein cholesterol concentrations, independently of body mass index, sequential organ failure (SOFA) score, and C-reactive protein levels. NEFAs and PUFAs concentrations were negatively correlated with the number of ventilator-free days. Among hospitalized patients with severe pneumonia, COVID-19 is independently associated with higher NEFAs (mainly linoleic and arachidonic acids) and lower apolipoprotein E and HDL concentrations. These features might act as mediators in COVID-19 pathogenesis and emerge as new therapeutic targets. Further investigations are required to define the role of NEFAs in the pathogenesis and the dysregulated immune response associated with COVID-19.Trial registration: NCT04435223.

Weaning patients with obesity from ventilatory support

PURPOSE OF REVIEW

Obesity prevalence is increasing in most countries in the world. In the United States, 42% of the population is obese (body mass index (BMI) > 30) and 9.2% is obese class III (BMI > 40). One of the greatest challenges in critically ill patients with obesity is the optimization of mechanical ventilation. The goal of this review is to describe respiratory physiologic changes in patients with obesity and discuss possible mechanical ventilation strategies to improve respiratory function.

RECENT FINDINGS

Individualized mechanical ventilation based on respiratory physiology after a decremental positive end-expiratory pressure (PEEP) trial improves oxygenation and respiratory mechanics. In a recent study, mortality of patients with respiratory failure and obesity was reduced by about 50% when mechanical ventilation was associated with the use of esophageal manometry and electrical impedance tomography (EIT).

SUMMARY

Obesity greatly alters the respiratory system mechanics causing atelectasis and prolonged duration of mechanical ventilation. At present, novel strategies to ventilate patients with obesity based on individual respiratory physiology showed to be superior to those based on standard universal tables of mechanical ventilation. Esophageal manometry and EIT are essential tools to systematically assess respiratory system mechanics, safely adjust relatively high levels of PEEP, and improve chances for successful weaning.

Outcomes of acute respiratory distress syndrome in COVID-19 patients compared to the general population: a systematic review and meta-analysis

INTRODUCTION

Acute respiratory distress syndrome (ARDS) due to coronavirus disease 2019 (COVID-19) often leads to mortality. Outcomes of patients with COVID-19-related ARDS compared to ARDS unrelated to COVID-19 is not well characterized.

AREAS COVERED

We performed a systematic review of PubMed, Scopus, and MedRxiv 11/1/2019 to 3/1/2021, including studies comparing outcomes in COVID-19-related ARDS (COVID-19 group) and ARDS unrelated to COVID-19 (ARDS group). Outcomes investigated were duration of mechanical ventilation-free days, intensive care unit (ICU) length-of-stay (LOS), hospital LOS, and mortality. Random effects models were fit for each outcome measure. Effect sizes were reported as pooled median differences of medians (MDMs), mean differences (MDs), or odds ratios (ORs).

EXPERT OPINION

Ten studies with 2,281 patients met inclusion criteria (COVID-19: 861 [37.7%], ARDS: 1420 [62.3%]). There were no significant differences between the COVID-19 and ARDS groups for median number of mechanical ventilator-free days (MDM: -7.0 [95% CI: -14.8; 0.7], p = 0.075), ICU LOS (MD: 3.1 [95% CI: -5.9; 12.1], p = 0.501), hospital LOS (MD: 2.5 [95% CI: -5.6; 10.7], p = 0.542), or all-cause mortality (OR: 1.25 [95% CI: 0.78; 1.99], p = 0.361). Compared to the general ARDS population, results did not suggest worse outcomes in COVID-19-related ARDS.

Obesity is a strong risk factor for short-term mortality and adverse outcomes in Mexican patients with COVID-19: a national observational study

Conflicting results have been obtained through meta-analyses for the role of obesity as a risk factor for adverse outcomes in patients with coronavirus disease-2019 (COVID-19), possibly due to the inclusion of predominantly multimorbid patients with severe COVID-19. Here, we aimed to study obesity alone or in combination with other comorbidities as a risk factor for short-term all-cause mortality and other adverse outcomes in Mexican patients evaluated for suspected COVID-19 in ambulatory units and hospitals in Mexico. We performed a retrospective observational analysis in a national cohort of 71 103 patients from all 32 states of Mexico from the National COVID-19 Epidemiological Surveillance Study. Two statistical models were applied through Cox regression to create survival models and logistic regression models to determine risk of death, hospitalisation, invasive mechanical ventilation, pneumonia and admission to an intensive care unit, conferred by obesity and other comorbidities (diabetes mellitus (DM), chronic obstructive pulmonary disease, asthma, immunosuppression, hypertension, cardiovascular disease and chronic kidney disease). Models were adjusted for other risk factors. From 24 February to 26 April 2020, 71 103 patients were evaluated for suspected COVID-19; 15 529 (21.8%) had a positive test for SARS-CoV-2; 46 960 (66.1%), negative and 8614 (12.1%), pending results. Obesity alone increased adjusted mortality risk in positive patients (hazard ratio (HR) = 2.7, 95% confidence interval (CI) 2.04-2.98), but not in negative and pending-result patients. Obesity combined with other comorbidities further increased risk of death (DM: HR = 2.79, 95% CI 2.04-3.80; immunosuppression: HR = 5.06, 95% CI 2.26-11.41; hypertension: HR = 2.30, 95% CI 1.77-3.01) and other adverse outcomes. In conclusion, obesity is a strong risk factor for short-term mortality and critical illness in Mexican patients with COVID-19; risk increases when obesity is present with other comorbidities.

Early Tracheostomy in Morbidly Obese COVID-19 Patients: A Case Series and Discussion of Institutional Practices

Tracheostomies are often utilized in critically ill patients on prolonged mechanical ventilation, to enhance respiratory function and facilitate ventilator weaning. Many coronavirus disease 2019 (COVID-19) patients develop serious respiratory illness requiring ventilator management. In the early phase of this pandemic, the risk of disease spread lead to the development of conservative guidelines which advocated delaying tracheostomy at least two to three weeks from intubation and, preferably, with negative COVID-19 testing. The morbidly obese patient population, however, presents a unique scenario in which early tracheostomy may be beneficial. In this article, we discuss our institution's current practices along with clinical outcomes with reference to intensive care literature and propose that early tracheotomy in COVID-19 patients should be considered on a case by case basis.

Respiratory supports of COVID-19 patients in intensive care unit: A systematic review

INTRODUCTION

We aimed to describe the respiratory supports and determine their association with clinical outcomes of COVID-19 patients in intensive care unit (ICU).

METHODS

A systemic literature search was conducted in PubMed, EMBASE, MedRxiv and BioRxiv database from December 2019 to 2 July 2020. Studies reporting the application of respiratory supports in COVID-19 patients admitted to ICU were included.

RESULTS

Forty studies with 15320 COVID-19 patients were included in this systematic review. The proportion of invasive mechanical ventilation (IMV) application in ICU patients with COVID-19 was 73.8%. Further analysis elucidated that the use rate of IMV in Asia, Europe and North America was 47%, 76.2% and 80.2%, respectively. The proportion of patients treated with prone positioning and IMV was 29.4%. 25.5% of COVID-19 patients requiring IMV developed ventilator-associated pneumonia. The mortality of patients treated with IMV was 51.1%, while only 17.5% of critically ill COVID-19 patients treated with non-IMV respiratory support died. Additionally, the utilization rate of IMV in non-survival patients was shown 17.26-folds (95%CI 2.89-103.24, p = 0.002) higher than that in survival patients, while the use rate of ECMO was no significant difference.

CONCLUSIONS

Our findings highlight respiratory supports of COVID-19 patients admitted to ICU in different continents. IMV is a life-saving strategy for critically ill COVID-19 patients with ARDS, yet the mortality remains very high.

A single-centre, prospective cohort study of COVID-19 patients admitted to ICU for mechanical ventilatory support

BACKGROUND

Mortality rates in COVID-19 patients in need of mechanical ventilation are high, with wide variations between countries. Most studies were retrospective, and results may not be generalizable due to differences in demographics, healthcare organization and surge capacity. We present a cohort of mechanically ventilated COVID-19 patients from a resource-rich, publicly financed healthcare system.

METHODS

Prospective study from a tertiary hospital. Consecutive SARS-CoV-2 positive adult patients admitted to the ICU for mechanical ventilation from 10 March 2020 to 04 May 2020 were included. Triage and treatment were protocolized. High-dose dalteparin was adjusted by D-dimer. Demographics, treatments and high-resolution physiological variables were collected. Outcomes were 30-day and hospital mortality. Data are medians (quartiles).

RESULTS

Of the 1484 persons in the hospital catchment area testing positive for SARS-CoV-2, 201 (13.5%) were hospitalized. Thirty-eight (19%) patients were mechanically ventilated, of whom five (13%) died. Of the 163 patients treated with supplemental oxygen, eight (5%) died. In ventilated patients (75% males, age 61 (53-70) years), severe, moderate and mild ARDS was present in 25%, 70% and 5%. Tidal volume ≤8 mL/kg ideal bodyweight was achieved in 34 (94%) patients. Proning and neuromuscular blockers were used in 19 (54%) and 20 (61%) patients. Duration of ventilation was 12 days (8-23). D-dimer peaked at 3.8 mg/L (2.1-5.3), and maximum dalteparin dose was 15 000 IU/24 h (10 000-15 000). Despite organizational changes, a high degree of adherence to treatment protocols was achieved.

CONCLUSION

In a prospective cohort study of mechanically ventilated COVID-19 patients treated in a resource-rich, publicly financed healthcare system, mortality was considerably lower than previously reported in retrospective studies.

Risk Factors for Invasive Pulmonary Aspergillosis in Critically Ill Patients With Coronavirus Disease 2019-Induced Acute Respiratory Distress Syndrome

Severe coronavirus disease 2019 pneumonia can lead to acute respiratory distress syndrome. Recently, several publications reported on coronavirus disease 2019-associated pulmonary aspergillosis. However, risk factors remain unclear. We retrospectively collected all the cases of coronavirus disease 2019 acute respiratory distress syndrome patients (n = 46) admitted to our 34-bed ICU between March 24, 2020, and May 25, 2020, and identified six patients that met the diagnosis of invasive pulmonary aspergillosis according to previously established definitions. This population exhibited higher severity scores at admission and less hospital discharge compared with noninvasive pulmonary aspergillosis patients. Chronic obstructive pulmonary disease, malnutrition, and systemic corticosteroid use were identified as risk factors for invasive pulmonary aspergillosis in coronavirus disease 2019-induced acute respiratory distress syndrome patients. Coronavirus disease 2019-associated pulmonary aspergillosis may be a serious concern regarding corticosteroids use to control the inflammatory response of coronavirus disease 2019-induced acute respiratory distress syndrome.

Implicating the effect of ketogenic diet as a preventive measure to obesity and diabetes mellitus

Obesity and diabetes are the two major metabolic complications linked with bad eating habits and the sedentary (lazy) lifestyle. In the worst-case situation, metabolic problems are a causative factor for numerous other conditions. There is also an increased demand to control the emergence of such diseases. Dietary and lifestyle improvements contribute to their leadership at an elevated level. The present review, therefore, recommends the use of the ketogenic diet (KD) in obesity and diabetes treatment. The KD involves a diet that replaces glucose sugar with ketone bodies and is effective in numerous diseases, such as metabolic disorders, epileptic seizures, autosomal dominant polycystic disease of the kidney, cancers, peripheral neuropathy, and skeletal muscle atrophy. A lot of high profile pathways are available for KD action, including sustaining the metabolic actions on glucose sugar, suppressing insulin-like growth factor-1 (IGF1) and phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathways, altering homeostasis of the systemic ketone bodies, contributing to lowering diabetic hyperketonemia, and others. The KD regulates the level of glucose sugar and insulin and can thus claim to be an effective diabetes approach. Thus, a stopgap between obesity and diabetes treatment can also be evidenced by KD.

How to ventilate obese patients in the ICU

Obesity is an important risk factor for major complications, morbidity and mortality related to intubation procedures and ventilation in the intensive care unit (ICU). The fall in functional residual capacity promotes airway closure and atelectasis formation. This narrative review presents the impact of obesity on the respiratory system and the key points to optimize airway management, noninvasive and invasive mechanical ventilation in ICU patients with obesity. Non-invasive strategies should first optimize body position with reverse Trendelenburg position or sitting position. Noninvasive ventilation (NIV) is considered as the first-line therapy in patients with obesity having a postoperative acute respiratory failure. Positive pressure pre-oxygenation before the intubation procedure is the method of reference. The use of videolaryngoscopy has to be considered by adequately trained intensivists, especially in patients with several risk factors. Regarding mechanical ventilation in patients with and without acute respiratory distress syndrome (ARDS), low tidal volume (6 ml/kg of predicted body weight) and moderate to high positive end-expiratory pressure (PEEP), with careful recruitment maneuver in selected patients, are advised. Prone positioning is a therapeutic choice in severe ARDS patients with obesity. Prophylactic NIV should be considered after extubation to prevent re-intubation. If obesity increases mortality and risk of ICU admission in the overall population, the impact of obesity on ICU mortality is less clear and several confounding factors have to be taken into account regarding the “obesity ICU paradox”.