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BREAKING NEWS
Source: COVID-19  May 28, 2020  2 months ago
MUST READ!!! Brazilian Respiratory Expert Says That COVID-19 Should Be Treated As A Thrombotic Disease
MUST READ!!! Brazilian Respiratory Expert Says That COVID-19 Should Be Treated As A Thrombotic Disease
Source: COVID-19  May 28, 2020  2 months ago
COVID-19: Medical researchers and respiratory experts from the University of São Paulo's Medical School say that blood clotting disorders may explain some of the worst symptoms of COVID-19, including respiratory failure and pulmonary fibrosis and that the focus should be on treating COVID-19 as a thrombotic disease caused by a virus.



Their research findings and reports were published in the international medical publication called Journal of Thrombosis And  Haemostasis. https://onlinelibrary.wiley.com/doi/abs/10.1111/jth.14844

The first medical scientists to report the "thrombotic nature" of the disease caused by the novel coronavirus (SARS-CoV-2) was Dr Elnara Negri, a researcher and pulmonologist at Hospital das Clínicas, the hospital complex run by University Of San Paulo. the largest in Latin America and Hospital Sírio-Libanês, a leading private hospital also in São Paulo City.

Dr Negri told Thailand Medical News, "Around March 25, we were treating a patient whose breathing was rapidly deteriorating. When she was intubated, I observed that her lungs were easy to ventilate. They were not hardened and stiff, as you'd expect in someone with acute respiratory distress. Shortly thereafter, I noticed that the patient had an ischemic toe."

The toe condition has been referred to as COVID-toe and can affect all ten toes. It is caused by the obstruction of the small blood vessels that circulate blood in the feet. Dr Negri observed a similar phenomenon many years ago in patients who underwent open heart surgery with extracorporeal circulation.

She said. "In the old days, a device was used to pump oxygen into the blood, and clots would form inside the blood vessels. I had seen the condition before and knew how to treat it.”

Dr Negri prescribed heparin, one of the most widely used anti-coagulant drugs worldwide. In under 18 hours, the patient's oxygen saturation improved, and her angry red toe regained a healthy pink color. The same effect was achieved with other patients treated at the Sírio-Libanês hospital.

Dr Negri added,  "Since that day, we have treated approximately 80 COVID-19 patients, and so far, none of them has died. Four are currently in the ICU. The rest are in the ward or have been discharged.”

Many studies and clinical observations show that severe COVID-19 patients require 28 days of mechanical ventilation on average, whereas those treated with heparin typically improve after ten to 14 days of intensive care.

A medical study by Dr Negri and her colleagues describing their clinical experience with the first 27 patients who were treated with the protocol developed at Sírio-Libanês hospital is available on medRxiv as a preprint (not yet peer-reviewed) version. https://www.medrxiv.org/content/10.1101/2020.04.15.20067017v3

Just after the first successful administration of heparin, DR Negri shared the finding with colleagues Dr Marisa Dolhnikoff and Dr Paulo Saldiva, pathologists at FM-USP who are coordinating the autopsies of patients who die from COVID-19 at Hospital das Clínicas.

Utilizing a minimally invasive technique developed during a project supported by FAPESP, the pathologists observed focal bleeding associated with mini-clots (microthrombi) in the small blood vessels of the lungs due to platelet clumping.

Dr Negri, Dr Dolhnikoff, Dr Saldiva and colleagues wrote their findings to the editor of the Journal of Thrombosis and Haemostasis, describing their research. Entitled "Pathological evidence of pulmonary thrombotic phenomena in severe COVID-19", this is the first article in the scientific literature to report this topic. Fully peer-reviewed and accepted for publication by the journal, the study could potentially revolutionize treatment of the disease.



COVID-19 was not the first coronavirus (CoV) to cause a public health crisis. The 2002-04 global outbreak of severe acute respiratory syndrome (SARS) caused almost 800 deaths, and Middle East respiratory syndrome (MERS) has killed 850 people since 2012. Both are coronavirus diseases. Neither has reached Brazil so far.

Dr Negri added, "Patients with SARS or MERS develop a strong inflammatory reaction in the lungs, and this can lead to a condition known as acute respiratory distress. The pulmonary alveoli, the tiny sacs in which carbon dioxide is exchanged for oxygen, fill up with dead cells, pus, and other inflammatory substances, hardening the lung tissue and impairing oxygenation of the organism."

It should be noted that COVID-19 is different, at least initially; SARS-CoV-2 does not cause severe inflammation of the lungs but does cause desquamation of the alveolar epithelial tissue.

Dr Negri further added, "The epithelial cells die after being infected, fall into the alveolar lumen and leave the basement membrane exposed. The organism's defense system thinks the region is raw or ulcerated and assumes there's a risk of hemorrhage, triggering a storm of interleukins (proteins that act as immune signalers) and what we call a 'coagulation cascade'. The platelets begin clumping together to form clots and 'plug the leak'."

These clots block the lung's small blood vessels and cause microinfarcts (cellular death or tissue necrosis). The regions of tissue that die due to a lack of blood supply are replaced by scar tissue in a process called fibrosis. In addition, microthrombi at the alveolar-blood vessel interface prevent the passage of oxygen to smaller arteries.

Dr Negri explained, "This is why COVID-19 patients may not have difficulty breathing even though their oxygen saturation is low. Many come to hospital walking and talking and very soon have to be intubated.”

Should the intravascular clotting not be rapidly treated, microinfarcts and fibrosis tend to spread throughout the lungs. Opportunistic bacteria and fungi may infect the damaged tissue and cause pneumonia, as SARS-CoV-2 leads to a decrease in the number of immune cells (lymphopenia). The patient may develop acute respiratory distress at the end of this process.

It was found that heparin helps avert this outcome via two mechanisms.The drug dissolves the microthrombi that prevent oxygen from flowing from the alveoli to the pulmonary blood vessels and contributes to the regeneration of the vascular endothelium, the layer of epithelial cells that line the interior of blood vessels.

Dr Negri further explained, "Damaged endothelium is like a road full of potholes. It hinders the flow of blood and leads to more clotting. This creates a snowball effect.”

Yet a third possible mechanism of action of heparin was described by a study recently conducted at the Federal University of São Paulo (UNIFESP) with FAPESP's support. In vitro experiments by the biomedical scientist Helena Bonciani Nader and colleagues showed that heparin brings about a 70% reduction in cell invasion by SARS-CoV-2. https://agencia.fapesp.br/use-of-anticoagulant-medication-leads-to-70-reduction-in-cell-infection-by-novel-coronavirus/33200/

Dr Negri added "There may be an anti-viral effect, which should be investigated in greater depth. As I like to say, we're changing tires without stopping the car.”

According to Dr Negri many lives may have been lost because patients diagnosed with COVID-19 were treated from the start as cases of acute respiratory syndrome and placed in ICU beds with lower levels of hydration and more intense mechanical ventilation. These two approaches worsen the thrombotic condition. 

The COVID-19 treatment paradigm needs to be urgently changed.

Dr Negri would like heparin to be administered as soon as the oxygen saturation level falls below 93%, which may happen between the seventh and tenth days after the onset of flu-like symptoms and can be detected by a physician in a private or public clinic.

She warned, "It's pointless to buy the drug from a pharmacy and swallow a pill. That will have no therapeutic effect and could cause bleeding. It must be injected, and a medic must calculate the right dose."

Also it should be stressed that heparin has significant effects on various physiological processes, and if the drug is administered without medical supervision, it can endanger the patient's life. Self-medication and failure to take side effects into account are particularly hazardous in the case of treatment for COVID-19.

However, a randomized clinical trial will be needed to demonstrate the therapeutic efficacy of heparin in COVID-19 patients. 

This implies that there will need to be two randomly chosen groups with similar characteristics, only one of which receives the drug. The results for this group are then compared with the outcomes for the group not given the drug.

The Brazilian researchers plan to begin this project shortly, in partnership with colleagues at the University of Toronto (Canada) and the University of Amsterdam (Netherlands).

Dr Negri added, "The trial will entail giving heparin to patients who come to the outpatient clinic with low oxygen saturation levels and seeing if treatment with the anti-coagulant can avoid the need for mechanical ventilation.”

The researchers are only waiting for approval from the Ethics Committee at Hospital das Clínicas and Brazil's National Research Ethics Committee (CONEP).

It should also be noted that there are lots more of studies now emerging about the lethal effects of clotting caused by the SARS-CoV-2 coronavirus.

For more on COVID-19, keep logging to Thailand Medical News. The only medical news site that is a repository of more than 2,000 medical articles on COVID-19.





 

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