The state may have the highest requirement for ICU units for Covid-19 patients but scientists at the country’s top research institute say that ICUs as they exist currently are more a hazard for patients and medical staff.
In a new paper, Professor A G Ramakrishnan of the Medical Intelligence and Language Engineering (MILE) Laboratory, Indian Institute of Science (IISc) and a postdoctoral student Dr Kaniksha Sharma of the same lab, said that the current design of most ICUs, where air is “recirculated through air-conditioning,” is unsuited for the treatment of patients with highly infectious diseases such as Covid-19.
The researchers added that this: “may be one of the causes of the thousands of infections among healthcare workers...one is not sure whether this is the reason behind the unusual death rate of patients put on ventilators too.”
Professor Ramakrishnan said that the deficiencies of ICU design became first glaring during the Sars-CoV-1 outbreak in the early 2000s. The researchers cite a study on healthcare workers in 2003, which discovered that 56% out of an assessed sample of 142 workers were asymptomatically infected despite using N95 masks, gloves and gowns.
Worse, while the death of patients placed on ventilator support is already about 50%, in the case of Covid-19, the authors cite an Associated Press article which stated that “80% or more of coronavirus patients placed on the machines in New York City had died.”
“The recirculation of the air by the centralized air-conditioning systems is what has led to the significant infection of our committed medical fraternity and has also led to deaths of doctors and nurses. It is also our considered opinion that none of the masks will be fully protective, if the air around is fully infected by the diffusion of the air constantly being breathed out by the patients, when a large number of patients are being taken care of in a (makeshift) ICU,” the researchers said.
The study adds that if air-conditioning is not necessary, then the ICU must be designed in such as way that a “forceful unidirectional flow of air” must be projected, running into an exhaust where it must be filtered through a layer of disinfecting soap or sodium hypochlorite solution or hot water.
“Studies clearly show that higher the temperature, faster the corona virus becomes inactive,” the authors said.
However, if air-conditioning is required, the researchers said there should be no forceful air flow. “Let the exhaust air go through an appropriate disinfecting solution,” they said, adding that it is also important to “de-link” air conditioning units in Covid-ICUs from other non-covid air-conditioning units to avoid circulating the air to other ICUs.
“A lot of what we suggest in the paper is common sense, and it would save lives if they were implemented,” Professor Ramakrishnan told DH.
He added that a scientist from PGIMER, Chandigarh had approached him following publication of the paper, and corroborated that such measures which had been independently adopted in their labs, had helped. “PGIMER has among the lowest infections among staff in the country,” he said.
Previous studies have suggested that countries in hot climates should ensure that indoor rooms are not dried out through overcooling with air conditioning. The studies note that maintaining indoor humidity levels between 40% and 60% will help limit airborne transmission of the virus.
The IISc paper was awarded the title of “best paper” at the IEEE Bangalore Humanitarian Technology Conference held between October 8 and 10.