Thick blood clots in kidneys, lungs and brains of Covid-19 patients scare doctors

As the novel coronavirus spread through new york City in late March, doctors at Mount Sinai Hospital noticed something strange happening to patients' blood.

Signs of blood thickening and clotting were being detected in several organs by doctors from different specialities. This could turn out to be one in all the alarming ways the virus ravages the body, as doctors there and elsewhere were beginning to realize.

A Mount Sinai, nephrologists noticed kidney dialysis catheters getting plugged with clots. Pulmonologists monitoring COVID-19 patients on mechanical ventilators could see portions of lungs were oddly bloodless. Neurosurgeons confronted a surge in their usual caseload of strokes because of blood clots, the age of victims skewing younger, with at least half testing positive for the virus.

"It's very striking what proportion this disease causes clots to make," Dr J Mocco, a mount Sinai neurosurgeon, said in an interview, describing how some doctors think COVID-19, the illness caused by the coronavirus, is quite a lung disease. In some cases, Mocco said, a stroke was a young patient's first symptom of COVID-19.

As colleagues from various specialities pooled their observations, they developed a replacement treatment protocol. Patients now receive high doses of a blood-thinning drug even before any evidence of clotting appears.

"Maybe, just maybe, if you prevent the clotting, you'll make the disease less severe," said Dr David Reich, the hospital president. The new protocol won't be used on individual high-risk patients because blood thinners can cause bleeding within the brain and other organs.

In the three weeks beginning mid-March, Mocco saw 32 stroke patients with significant blood blockages within the brain, double the standard number for that period.

Five were unusually young, under age 49, with no apparent risk factors for strokes, "which is crazy," he said. "Very, very atypical." The youngest was only 31.

At least half the 32 patients would test positive for COVID-19, Mocco said. Meanwhile, Dr Hooman Poor, a Sinai lung specialist, found himself working a late shift with 14 patients on ventilators. The ventilator readings weren't what he expected.

The lungs failed to seem stiff, as is common in pneumonia. Instead, it appeared blood wasn't circulating freely through the lungs to be aerated with each breath.

Poor saw a kidney doctor that night, who remarked that dialysis catheters were often getting blocked with clots.

"And I said, 'It's funny that you simply mentioned that because I feel like all these patients have blood clots in their lungs,' "Poor recalled.

Reich, the hospital president, told Poor about the surge in strokes seen by Mocco and said the two doctors should team, setting off days of discussions and meetings with the hospital's department heads.

As their wards began to overflow with COVID-19 patients, the Mount Sinai doctors read papers describing similar findings from doctors in China's Hubei province and other hard-hit areas and discussed them with their peers in phone calls and webinars.

Mocco called neurosurgeons he knows elsewhere within the country. At Philadelphia's Thomas Jefferson University Hospital, Dr Pascal Jabbour had begun to work out the same surge in strokes among people with COVID-19. The way his patients' blood congealed reminded him of congenital conditions like lupus, or certain cancers.

"I've never seen the other viruses causing that," Jabbour said.

In Boston, the Beth Israel Deaconess Medical centre began a trial earlier this month to determine if tPA, an anti-clotting drug, could help severely sick COVID-19 patients.

Clotting can develop in anyone who gets very sick and spends long periods of your time immobile on a ventilator. Still, doctors say the matter appeared to show up sooner in COVID-19 patients as a more direct consequence of the virus.

At Mount Sinai, patients in medical care often receive the blood-thinning agent heparin in weaker prophylactic doses. Under the new protocol, higher doses of heparin usually wont to dissolve clots will be given to patients before any lumps are detected.

The treatment joins a growing toolbox at the hospital, where some patients are getting the antibody-rich plasma of recovered COVID-19 patients or experimental antiviral drugs.

The American Society of Hematology, which has also seen the clotting, says in its guidance to physicians that the advantages of the blood-thinning therapy for COVID-19 patients not already showing signs of clotting are "currently unknown."

"I certainly wouldn't expect harps to play and angels to sing and other people to simply rip out their intravenous lines and waltz out of the hospital," said Reich. "It's likely going to be something where it just moderates the extent of the disease."