The use of protective mechanical ventilation during extracorporeal membrane oxygenation for the treatment of acute respiratory failure.

Acute respiratory failure (ARF) strikes an estimated two million people in the United States each year, with care exceeding US$50 billion. The hallmark of ARF is a heterogeneous injury, with normal tissue intermingled with a large volume of low compliance and collapsed tissue. Mechanical ventilation is necessary to oxygenate and ventilate patients with ARF, but if set inappropriately, it can cause an unintended ventilator-induced lung injury (VILI). The mechanism of VILI is believed to be overdistension of the remaining normal tissue known as the 'baby' lung, causing volutrauma, repetitive collapse and reopening of lung tissue with each breath, causing atelectrauma, and inflammation secondary to this mechanical damage, causing biotrauma. To avoid VILI, extracorporeal membrane oxygenation (ECMO) can temporally replace the pulmonary function of gas exchange without requiring high tidal volumes (VT) or airway pressures. In theory, the lower VT and airway pressure will minimize all three VILI mechanisms, allowing the lung to 'rest' and heal in the collapsed state. The optimal method of mechanical ventilation for the patient on ECMO is unknown. The ARDSNetwork Acute Respiratory Management Approach (ARMA) is a Rest Lung Approach (RLA) that attempts to reduce the excessive stress and strain on the remaining normal lung tissue and buys time for the lung to heal in the collapsed state. Theoretically, excessive tissue stress and strain can also be avoided if the lung is fully open, as long as the alveolar re-collapse is prevented during expiration, an approach known as the Open Lung Approach (OLA). A third lung-protective strategy is the Stabilize Lung Approach (SLA), in which the lung is initially stabilized and gradually reopened over time. This review will analyze the physiologic efficacy and pathophysiologic potential of the above lung-protective approaches.

The Importance of Serum Homocysteine as a Biomarker in Diabetic and Obese COVID-19 Patients.

Homocysteine is a possible risk marker in hematological complications of COVID-19 infection. This study aimed to elucidate the significance of homocysteine as a biomarker for COVID-19 infection, and the relation of homocysteine with COVID-19 severity in obese people and diabetic patients.  The study groups were 1- COVID-19 patients + Diabetic + Obese (CDO), 2- COVID-19 patients + Diabetic (CD), 3- COVID-19 patients + Obese (CO), 4- Healthy Group (HG). Serum levels of homocysteine, IL-6, D-dimer, vitamin B12, and folate were measured by a fully automated biochemistry device Cobas 6000 analyzer series. The mean serum concentration of homocysteine in the COD, CD, CO and H groups were 32.0114, 23.604, 19.4154, and 9.3206 umol/l respectively. The mean concentration of homocysteine levels between every two groups was statistically significant differences (P<0.05) except for the CD and the CO group (P=0.957). In the CDO group, the males have higher mean concentrations than females (P<0.05). The means of homocysteine concentrations in the CDO group among different age groups were different (P <0.001). The serum homocysteine level in the CDO group has a strong positive correlation (R=0.748) with D-dimer and a strong negative correlation (R= - 0.788) with serum folate, while its correlation with serum vitamin B12 is moderate negative (-0.499) and its correlation with serum IL-6 is weakly positive (R=0.376). The AUC value for homocysteine in predicting COVID-19 in the CDO group was 0.843, while 0.714 for the CD group, and 0.728 for the CO group. The serum homocysteine concentration test for all study groups was compared to the serum IL-6 test and the sensitivity was equal to 95% and its specificity was 67.5%. Serum homocysteine has potential predictive power in COVID-19 patients, and the severity of COVID-19 infection and the type of comorbidity is associated with higher sensitivity and specificity of homocysteine serological tests.

Effect of low dose acetylsalicylic acid and anticoagulant on clinical outcomes in COVID-19, analytical cross-sectional study.

Background and aims: The therapeutic strategy for the treatment of known sequelae of COVID-19 has shifted from reactive to preventative. In this study, we aim to evaluate the effects of acetylsalicylic acid (ASA), and anticoagulants on COVID-19 related morbidity and mortality. Methods: This record-based analytical cross-sectional study targeted 539 COVID-19 patients in a single United States medical center between March and December 2020. Through a random stratified sample, we recruited outpatient (n = 206) and inpatient (n = 333) cases from three management protocols, including standard care (SC) (n = 399), low-dose ASA only (ASA) (n = 112), and anticoagulation only (AC) (n = 28). Collected data included demographics, comorbidities, and clinical outcomes. The primary outcome measure was inpatient admission. Exploratory secondary outcome measures included length of stay, 30-day readmission rates, medical intensive care unit (MICU) admission, need for mechanical ventilation, the occurrence of acute respiratory distress syndrome (ARDS), bleeding events, clotting events, and mortality. The collected data were coded and analyzed using standard tests. Results: Age, mean number of comorbidities, and all individual comorbidities except for asthma, and malignancy were significantly lower in the SC compared to ASA and AC. After adjusting for age and comorbidity via binary logistic regression models, no statistical differences were found between groups for the studied outcomes. When compared to the SC group, ASA had lower 30-day readmission rates (odds ration [OR] 0.81 95% confidence interval [CI] 0.35-1.88, p = 0.63), MICU admission (OR 0.63 95% CI 0.34-1.17, p = 0.32), ARDS (OR 0.71 95% CI 0.33-1.52, p = 0.38), and death (OR 0.85 95% CI 0.36-1.99, p = 0.71). Conclusion: Low-dose ASA has a nonsignificant but potentially protective role in reducing the risk of COVID-19 related morbidity and mortality. Our data suggests a trend toward reduced 30-day readmission rates, ARDS, MICU admissions, need for mechanical ventilation, and mortality compared to the standard management protocol. Further randomized control trials are needed to establish causal effects.

Rationales and uncertainties for aspirin use in COVID-19: a narrative review.

OBJECTIVES: To review the pathophysiology of COVID-19 disease, potential aspirin targets on this pathogenesis and the potential role of aspirin in patients with COVID-19. DESIGN: Narrative review. SETTING: The online databases PubMed, OVID Medline and Cochrane Library were searched using relevant headlines from 1 January 2016 to 1 January 2021. International guidelines from relevant societies, journals and forums were also assessed for relevance. PARTICIPANTS: Not applicable. RESULTS: A review of the selected literature revealed that clinical deterioration in COVID-19 is attributed to the interplay between endothelial dysfunction, coagulopathy and dysregulated inflammation. Aspirin has anti-inflammatory effects, antiplatelet aggregation, anticoagulant properties as well as pleiotropic effects on endothelial function. During the COVID-19 pandemic, low-dose aspirin is used effectively in secondary prevention of atherosclerotic cardiovascular disease, prevention of venous thromboembolism after total hip or knee replacement, prevention of pre-eclampsia and postdischarge treatment for multisystem inflammatory syndrome in children. Prehospital low-dose aspirin therapy may reduce the risk of intensive care unit admission and mechanical ventilation in hospitalised patients with COVID-19, whereas aspirin association with mortality is still debatable. CONCLUSION: The authors recommend a low-dose aspirin regimen for primary prevention of arterial thromboembolism in patients aged 40-70 years who are at high atherosclerotic cardiovascular disease risk, or an intermediate risk with a risk-enhancer and have a low risk of bleeding. Aspirin's protective roles in COVID-19 associated with acute lung injury, vascular thrombosis without previous cardiovascular disease and mortality need further randomised controlled trials to establish causal conclusions.

Multiple Thrombotic Events in a 67-Year-Old Man 2 Weeks After Testing Positive for SARS-CoV-2: A Case Report.

BACKGROUND Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the viral pathogen responsible for coronavirus disease 2019 (COVID-19), a pandemic respiratory illness. While many patients experience mild to moderate symptoms, severely affected patients often progress to acute respiratory distress syndrome (ARDS). Specific to COVID-19, abnormal coagulability appears to be a principal instigator in the progression of disease severity and mortality. In this report we summarize a case of COVID-19 in which extreme thrombophilia led to patient demise. CASE REPORT A 67-year-old man in New York presented to the hospital 14 days after testing positive for SARS-CoV-2 at an outpatient site. His initial presenting symptoms included sore throat, headache, fever, and diarrhea. He was brought in by his wife after developing sudden onset confusion and dysarthria. The patient's clinical picture, which was unstable on presentation, further deteriorated to involve significant desaturations, generalized seizure activity, and cardiac arrest requiring resuscitation. Upon return to spontaneous circulation, the patient required intensive care unit admission, mechanical ventilation, and vasopressor increases. Comprehensive workup uncovered coagulopathy with multiple thrombotic events involving the brain and lungs as well as radiographic evidence of severe lung disease. In the face of an unfavorable clinical picture, the family opted for comfort care measures. CONCLUSIONS In this case report on a 67-year-old-man with COVID-19, we present an account of extreme hypercoagulability that led to multiple thrombotic events eventually resulting in the man's demise. Abnormal coagulation 14 days from positive testing raises the question of whether outpatients with COVID-19 should be screened for hypercoagulability and treated with prophylactic anticoagulation/antiplatelet agents.

Synthesis, Anti-inflammatory and Antibacterial Activities of Novel Pyrazolo[4,3-g]pteridines.

A novel series of 6-substituted pyrazolo[3,4-g]pteridines 2-9 and pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pteridin-2(3H)-one (thione) 10 and 11 was synthesized using the starting compound 3,7-dimethyl-1-phenylpyrazolo[4',3':5,6]pyrazino[2,3-d][1,3]oxazin-5(1H)-one 2. The structure of the newly synthesized compounds was elucidated by IR, (1)H-NMR, (13)C-NMR, mass spectroscopy and elemental analyses. The anti-inflammatory activity of all the newly synthesized compounds was evaluated using the carrageenan-induced paw oedema test in rats using indomethacin as the reference drug. Compound 11 and the two derivatives 7f and 8b were the most active compounds, showing an activity comparable to indomethacin. Also, the synthesized compounds were evaluated for their antibacterial activity against Gram-positive bacteria (Staphylococcus aureus and Bacillus cereus) and Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) using chloramphenicol as control. The pyrazolotriazolopteridin-2-thione 11, 6-hydroxyethyl- 6a, 6-(4-nitrophenyl)-7g, and 6-(phenylamino) 8b derivatives were found to be the most active compounds against the Gram-positive species. None of them showed any activity against Gram-negative species.