Monday, April 13, 2020

COVID-19 : New Realities in the Learning-Treatment Curve

"In many ways, it's different than anything we have seen before."
"[With some Ottawa patients] we're giving them all the oxygen we can give them without putting them on a breathing machine, and they're wide awake and talking."
"Unless somebody seems to be failing, or their oxygen level is truly at this critical life-changing level, we can maybe hesitate [rationing ICU beds and ventilators]."
"But let me be explicitly clear here:  These are still the exceptions. The majority are failing -- They need to have a tube put down [their throats] and put on a breathing machine to help them breathe."
Dr.James Downar, specialist, critical care/palliative care, The Ottawa Hospital

"Sometimes you have to relax the breathing muscles so they're able to open their mouth and accept the tube being inserted."
"If they're incredibly sick we need to take over their breathing completely, and so we fully sedate them [medically-induced coma]."
"We don't allow them to wake up from that anesthetic until their lungs have healed. And then once they've healed, or if they're not that sick, we can allow them to be reasonably aware."
"We've become expert lip readers in the intensive care unit."
Dr.John Granton, head, division of respirology, University Health Network, Sinai Health System, Toronto
A tube from a ventilator on a sedated patient infected with COVID-19 at the intensive care unit of the Peupliers private hospital in Paris, April 7, 2020. Thomas Coex/AFP via Getty Images
The H1N1 and SARS experience taught the medical community that sometimes it takes several weeks, a month or even a greater period of time for people to recover from extreme respiratory treatment before it becomes feasible for them to be "liberated" from breathing machines. People with a significant underlying condition such as chronic obstructive pulmonary disease, risk never coming off respirators. 
In the trenches of the medical emergency while coping with a wide sweep of new cases of COVID in New York City, exhausted doctors saw reason to be concerned that breathing tubes and pressures used to open up the air sacs in the lungs of those critically ill, could be the cause of even greater physical harm to patients' state of health and survival. Leaving some doctors to ask whether ventilating some patients could be averted entirely and in so doing decrease the mortality rate.

It is not only the lungs that are being affected by the pandemic virus, making them stiff and inflamed. Other parts of the body are affected, including the heart, though what is not clear is whether this is a direct effect of the coronavirus on the heart causing heart failure in some instances, or whether the cause is the virus interfering with the body's coagulation system, thus increasing risk of blood clots developing.
Some patients with severe COVID-19 arrive to hospital with such low blood oxygen levels they should be gasping for breath, unable to speak in full sentences, incoherent, and barely conscious, a phenomenon reported in the U.S., along with Italy, and now in Canada as well. This, while the patients are not in a state of actual distress since they're able to talk, and they remain lucid. Not at all the classic acute respiratory distress syndrome the medical community is accustomed to, and doctors are recommended by guidelines to treat as such.
One critical care doctor is urging  his colleagues to remain cautious in deciding who is being ventilated, and how, likening the phenomenon to altitude sickness, the kind of brain epoxy experienced by high-altitude mountaineers when low levels of oxygen affect the cerebral process. The pressure involved in administering ventilation treatment may be doing great harm to lungs and in these circumstances some patients may be treated more safely with less aggressive treatment; with oxygen masks or nasal tubes.

Turning patients onto their stomachs in some situations to allow for improvement if gas exchanges results is another alternative. COVID-19 can cause pneumonia, interfering with the capacity of oxygen to infiltrate the lungs and the bloodstream, even while the greater majority, amounting to 80 percent of infections are mild. Of confirmed cases in Canada, about six percent have required ICU admission. Ventilators provide oxygen along with pressure to open the alveoli -- air sacs in the lungs -- to allow oxygen penetration, and to expel carbon dioxide. Potentially live-saving, the procedure can exacerbate injury to the lungs.
Dr.Downar recognizes a new strategy, to hold off on intubation, as per an Ontario "triage protocol" should hospitals be forced to ration ICU beds and ventilators, which Dr.Downar helped draft, in which it remains unclear what proportion of patients could be discharged to see another day. The Journal of the American Medical Association published a study this week which involved 1,591 people infected with the novel coronavirus, admitted to ICUs in the Lombardy region of Italy between February 20 and March 18.

A large proportion -- 88 percent -- required mechanical ventilation and as of March 25, 26 percent of ICU patients had died, 15 percent were discharged, and 58 percent still remained in the ICU. Of that number, the median age was 62, and 82 percent were men. People who have undergone the process of mechanical ventilation describe it as dreadful, beyond belief. First, they're sedated to a calm state. Once the tube has been installed in the throat the patient cannot speak and must communicate with the use of a board, or by moving their lips.
In COVID-19 lockdown, families are not permitted inside the ICU, with hospitals in lockdown, where normally they would be at the bedside. "We're trying to update them by phone, we're trying to do FaceTime. To have to see a critically ill family member through a video call and have your questions answered by somebody wearing a face mask ... it's not the way we like to do things. But it's better than nothing", explained Dr.Downar.

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