Of Ventilators & Ventilation: Engineering the Coronavirus Out of the Workplace

By NORTIN HADLER, MD (2)

We are all reeling from the language of the COVID-19 pandemic: fatality rates, spread, PPE, distancing, pneumonia, anti-viral drugs, ventilators, second wave, vaccines, serological testing, etc. All of this focuses on the infection with the SARS-CoV-2 coronavirus, and for good reason. People are sick and dying from this infection. However, there is murmuring that will grow in volume as COVID-19 subsides: Will this happen again? Is the annual flu season to become more alarming in the future? Will we forever be waiting for vaccines and anti-viral drugs with bated breath?

If we step back and view this nightmare from the perspective of infectivity rather than infection, there may be a way out of this conundrum. Coronaviruses are one of several categories of virus with a proclivity for human respiratory infection. Coronaviruses join Influenza, Ebola, SARS and MERS as respiratory riboviruses. These viruses are tiny bundles, virions, containing a little RNA and not much else. Left alone, little happens. But if they manage to get into a target cell, they commandeer the cell’s metabolic machinery to do their malevolence. They get to their target cell because we inhale them as virions that are aerosolized or carried in the droplets that are produced when infected people exhale. Droplets that are not inhaled settle on surfaces, including surgical and N95 masks, where water evaporates freeing virions to aerosolize unless they are somehow bound to the surface. They are so tiny that even the N95 mesh is an inefficient barrier. One would need filters with such tiny pores that they would impede inhaling.

Infectivity of these riboviruses and probably severity of disease are dose dependent. The more virions one inhales the more likely one is infected. That’s the reason physical distancing is advised. However, these riboviruses retain infectivity for many hours on surfaces during which air currents can launch them and keep them afloat. That’s of little concern out of doors where they are diluted, but not indoors. Modern architectures and civil engineers are well aware of issues that relate to stagnation in built environments. HVAC systems are designed as a compromise between the need to recirculate air for the sake of efficient heating/cooling while turning to filters and air exchanges for the sake of air purity, particularly with regard to inert particulate materials. Concerns about airborne illnesses are seldom primary. In most hospitals, certain rooms are designed as “reverse flow” rooms for patients with contagious diseases with exhaust mechanisms so that the room’s air is released to outside the building, not back into general circulation in the building. Some operating rooms, particularly orthopedic surgical suites, have lamellar flow ventilation to decrease the likelihood of introducing an airborne pathogen along with orthopedic hardware. But otherwise hospitals and other workplaces are not designed with regard to infectivity.

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Strange Times in Public Health

By ANISH KOKA, MD

A number of politically tinged narratives have divided physicians during the pandemic. It would be unfortunate if politics obscured the major problem brought into stark relief by the pandemic: a system that marginalizes physicians and strips them of agency.

In practices big and small, hospital-employed or private practice, nursing homes or hospitals, there are serious issues raising their heads for doctors and their patients.

No masks for you

When I walked into my office Thursday, March 12th, I assembled the office staff for the first time to talk about COVID. The prior weekend had been awash with scenes of mayhem in Italy, and I had come away with the dawning realization that my wishful thinking on the virus from Wuhan skipping us was dead wrong. The US focus had been on travel from China and other Far East hotspots. There was no such limitation on travel from Europe. The virus had clearly seeded Italy and possibly other parts of Europe heavily, and now the US was faced with the very real possibility that there was significant community spread that had occurred from travelers from Europe and Italy over the last month. I had assumed that seeing no cases in our hospitals and ICUs by early March meant the virus had been contained in China. That was clearly not the case.

Our testing apparatus had also largely been limited in the US to symptomatic patients who had been to high-risk countries. If Europe was seeded, this meant we had not been screening nearly enough people. When I heard the first few cases pop up in my county, it was clear the jig was up. It was pandemic panic mode time. There was a chance that there were thousands of cases in the community we didn’t know about and that we were weeks away from the die-off happening in hospitals in China and Italy. So what I told the staff the morning of March 12th was that we needed to start acting now as if there was significant spread of COVID in the community. This meant canceling clinic visits for all but urgent patients, wearing masks, trying to buy masks, attention to hand hygiene, cleaning rooms between patients, screening everyone for flu-like symptoms before coming to the office, and moving to a skeleton staff in the office. I left the office that day wearing a mask as I headed to the ER.

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A Brief History of Failure: Performance Measurement

By KIP SULLIVAN

Over the last three decades, health care policymakers in Minnesota, where I live, have gotten into a bad habit: They recommend policies without asking whether there is sufficient evidence to implement the policy, and without spelling out how the policy is supposed to work. Measurement and “pay for performance” (P4P) schemes illustrate the problem. Multiple Minnesota commissions, legislators, agencies, and groups have endorsed the notion that it’s possible to measure the cost and quality of doctors, clinics, and hospitals accurately enough to produce results useful to regulators, patients, providers, and insurers.

But these policymakers did so with no explanation of how system-wide measurement was supposed to be done accurately, and without any reference to research demonstrating that accurate system-wide measurement is financially or technically feasible. The Minnesota Health Care Access Commission (in 1991) and the Minnesota Health Care Commission (in 1993) were the first of several commissions to exhibit this “shoot-first, aim-later” mentality. Both commissions recommended the establishment of massive data collection and reporting systems, and both articulated breathtaking expectations of the “report cards” these systems would produce. According to the latter commission, for example, the data collection and number crunching would facilitate “feedback of data that reflects the entire scope of the health care process, from the inputs or structural characteristics of health care to the processes and outcomes of care.” (p. 134) Yet neither commission offered even the crudest details on how such a scheme would be executed nor what it would cost, and, not surprisingly, neither commission offered evidence supporting their high hopes.

In 2008, two other commissions and the Minnesota Legislature exhibited the same casual attitude toward evidence and details. That year, the Legislature, egged on by the commissions, passed a law requiring the Minnesota Department of Health (MDH) to create a “standardized set” of quality measures for Minnesota that would be used to punish and reward “health care providers” (Minnesota Statutes, Section 62U.02). The law offered a few guidelines (such as MDH should “seek to avoid increasing the administrative burden on health care providers”), but it offered no details on how MDH was supposed to create useful measures.