‘More ventilators!’ cried the journalists on Twitter. ‘Yes, more ventilators!’ replied the politicians. ‘Where are the ventilators?’ demanded the journalists, now screaming on television. ‘Yes, even more!’ replied the government, somewhat nonsensically.
I am a critical care physician, specialising in the use of such machines. I’m flattered by all the attention our tools are receiving. But I fear the current clamour reminds me of nothing so much as the panic buyers of toilet-paper stampeding over each other in early March. When the history of the Covid-19 pandemic in the Western world is written, I do not believe ‘massive ramp-up of ventilator manufacturing,’ will be credited with our deliverance. Let me explain why.
Ventilators do not cure any disease. They can fill your lungs with air when you find yourself unable to do so yourself. They are associated with lung diseases in the public’s consciousness, but this is not in fact their most common or most appropriate application.
There are many reasons a person might not be able to fill their lungs with air. Undergoing a major abdominal surgery under general anaesthesia is perhaps chief among them. Other causes of coma, like drug intoxication or head trauma, also necessitate mechanical ventilation. While some neurological disorders, such as Guillain-Barré syndrome or polio, leave a person awake, but too weak to work the bellows of the lung (the diaphragm.) In all of these cases, the ventilator pushes fresh air containing oxygen into healthy lungs which can transmit the oxygen to the bloodstream.
Conversely, when a person has a severe lung problem, you might imagine that some proportion of their lung tissue continues to receive air when they breath, but fails to transmit this oxygen to the bloodstream. To compensate for these malfunctioning bits of lung tissue, the person breathes harder and faster, as though they were running a marathon.
One can only run a marathon for so long before those same bellows of the lung fatigue, and eventually fail.