To fight the Covid-19 pandemic, we need several gears starting from hand sanitisers, surgical masks to hand gloves. In taking care of infected patients, healthcare workers require personal protective equipment (PPE), which includes masks, gowns, gloves, and eye protective gears. As there is no vaccine or medicine, our immune system is our best as well as sole defence for responding quickly and buying time in fighting against this pathogenic microorganism.
Upon getting infected, if our respiratory system keeps getting battered requiring artificial help for supplying oxygen to the body, the need for the help of a ventilator shows up. As doctors say, "Ventilators aren't really making any therapeutic contributions." The purpose is basically to buy time for the critically ill patients so that the immune system gets extra legroom to respond to the attacking virus. Basically, a ventilator blows oxygen-rich air into the lung through a tube inserted in the patient's nose or mouth that moves down into the airway.
Every country is running short of supply of this device, which costs tens of thousands of dollars. For example, Bangladesh has less than 2000 ventilators to support Covid-19 care needs of 160 million people. Governments across the world are desperately trying to increase stock of ventilators. But recent study reports have raised questions about the value such urgently needed device adds in increasing the recovery rate of critically ill Covid-19 infected patients.
The human body has a superb defence system equipped with a rich arsenal to defend against different types of pathogens. There has been an ongoing cat and mouse game between our natural defence system and viruses. Viruses have been evolving to trick, bypass, and evade these defences. Our immune systems have, in turn, learned to recognise and deter these virus's stealthy tactics. After being attacked by an unknown virus, such fights often go on for days and weeks before either our defence system succeeds, or succumbs to it. Upon getting inside our body through mouth or nose or eyes, Covid-19 borrows cellular machinery to build more viruses before infected cells detect the intruders and raise the alarm. In responding to distress signals, the immune system destroys infected cells to deprive the virus of its replication capacity and can lead to the reduction of viral load on the patient. This process is taking days and weeks for the case of Covid-19. And during this period, Covid-19 keeps decreasing the functioning of lung in supplying oxygen to different body parts. At the last leg of this fight, the ventilator is administered to supply highly oxygenated air to the lung to buy a bit more time to support the immune system to generate enough antibodies to win the fight.
At this point in time, over 2.0 million people across the world have been tested positive for Covid-19 infection. Based on available data, it appears that there is one death against four people recovering from this menace. At this early stage, the number of patients dying in intensive care units (IUCs) and on mechanical ventilation is unknown. Among the published analysis, an investigation involving 710 Covid-19 patients in China showed that among 52 intensive care unit (ICU) patients, 22 required mechanical ventilation. Among these 22 patients, 19 died. Such a result indicates that 86 per cent patients who were given mechanical ventilation support died. In another study considering patients in China, it has been reported that as high as 97 per cent (31 among 32) mechanically ventilated patients died.
Information published from the Intensive Care National Audit and Research Centre (ICNARC) in the UK, reported in the media, appears to be quite comprehensive to draw a lesson from. This analysis is based on 165 patients admitted to ICUs. Among them 79 or 48 per cent of the patients died. Among the 98 patients who received advanced respiratory support through invasive ventilation, 66 per cent died.
Such a high mortality rate among the critically ill Covid-19 patients requiring mechanical ventilation for providing oxygen-rich air to the lung raises a critical policy question-how far we should be desperate to source ventilators to enrich our arsenals to fight against this crisis. As reported in New York-based Business Insider, doctors are of the opinion to stop using them as "80 per cent of NYC's coronavirus patients who are put on ventilators ultimately die." Such a high mortality rate could be due to the fact that a ventilator is an extreme step saved for the worst-affected patients, who typically have the highest chance of dying from respiratory failure. Moreover, as some doctors say, invasive means of using ventilators could be further harming coronavirus patients. It's widely reported that the artificial breathing tube can sometimes allow germs to enter the lungs, causing infection, which increases the risk level. There is also the issue of the availability of trained healthcare professionals and the need for other medicines for administering the ventilators. For example, there is a need of placing critically ill patients in deep sedation. Some patients have to stay sedated over several weeks.
Here are three pertinent issues. The first one is about the shortage of ventilators. The need for trained healthcare professionals and other medicines in administering mechanical ventilation is the second issue. And the third issue is about the very low success rate in taking care of patients with the support of ventilators. To address all these issues simultaneously, we should take measures to reduce the number of people catching the disease in the first place-through following all the health advices, including social distancing and hygiene rules. The next vital one is to enhance our immune system so that the natural response time is made shorter, and the body can sustain a prolonged period in the fight with the pathogens.
Ventilator is no panacea to save Covid-19 infected patients. Relatively poor outcomes of critically ill Covid-19 patients receiving mechanical ventilation raises the need for policymakers to perform analysis on optimum resource utilisation for fighting the crisis. This means that difficult decisions will have to be made by policymakers, staff, families, and patients about the limits of support that could be provided by ventilators, even if they are made available. Decision making may also raise ethical dilemmas, particularly in taking decisions about how desperate we should be in increasing the stock of ventilators in our fight against Covid-19.
M Rokonuzzaman, PhD is an academic and researcher on technology, innovation and policy.
