Name: How do ventilators work? - Alex Gendler
Uploaded: 2020-10-23T18:33:36.000Z
Duration: 5 min 42 s
Description: Thousands of YouTube videos with English-Chinese subtitles! Now you can learn to understand native speakers, expand your vocabulary, and improve your pronunciation...

In the 16th century, Flemish physician  Andreas Vesalius

Advanced passive voice

described how a suffocating animal  could be kept alive

Participle clauses with adverbial meaning

by inserting a tube into its trachea and blowing air to inflate its lungs.

In 1555, this procedure didn't warrant much acclaim.

But today, Vesalius's treatise  is recognized

as the first description  of mechanical ventilation—

we need to understand how  the respiratory system works.

We breathe by contracting our diaphragms,  which expands our chest cavities.

This allows air to be drawn in,  inflating the alveoli—

Each of these tiny balloons is surrounded  by a mesh of blood-filled capillaries.

This blood absorbs oxygen  from the inflated alveoli

the CO2 is exhaled alongside  a mix of oxygen and other gases.

When our respiratory systems  are working correctly,

But the respiratory system can be  interrupted by a variety of conditions.

Sleep apnea stops diaphragm muscles from contracting.

Asthma can lead to inflamed airways  which obstruct oxygen.

And pneumonia, often triggered  by bacterial or viral infections,

triggering an immune response  that can cause lethal inflammation

All these situations render the lungs  unable to function normally.

But mechanical ventilators  take over the process,

getting oxygen into the body  when the respiratory system cannot.

These machines can bypass  constricted airways,

and deliver highly oxygenated air  to help damaged lungs diffuse more oxygen.

There are two main ways  ventilators can work—

pumping air into the patient's lungs  through positive pressure ventilation,

or allowing air to be passively drawn  in through negative pressure ventilation.

ventilation techniques largely  focused on negative pressure,

which closely approximates  natural breathing

and provides an even distribution  of air in the lungs.

To achieve this, doctors created  a tight seal around the patient's body,

either by enclosing them in  a wooden box or a specially sealed room.

decreasing air pressure, and allowing the patient's chest cavity

In 1928, doctors developed  a portable, metal device

with pumps powered  by an electric motor.

became a fixture in hospitals  through the mid-20th century.

However, even the most compact  negative pressure designs

This led hospitals in the 1960's to shift  towards positive pressure ventilation.

For milder cases,  this can be done non-invasively.

Often, a facemask is fitted  over the mouth and nose,

and filled with pressurized air  which moves into the patient's airway.

require a device that takes over  the entire breathing process.

A tube is inserted  into the patient's trachea

with a series of valves  and branching pipes

forming a circuit for inhalation  and exhalation.

allows for monitoring the patient's  breathing and adjusting the airflow.

These machines aren't used  as a standard treatment,

Enduring this influx of pressurized air  requires heavy sedation,

and repeated ventilation  can cause long-term lung damage.

ventilators can be the difference  between life and death.

have shown that they're even more  essential than we thought.

Because current models  are bulky, expensive,

and require extensive training to operate, most hospitals only have a few in supply.

This may be enough  under normal circumstances,

but during emergencies,  this limited cache is stretched thin.

The world urgently needs more low-cost and portable ventilators,

as well as a faster means  of producing and distributing