Artificial ventilation or respiration is when a machine assists in a metabolic process to exchange gases in the body by pulmonary ventilation, external respiration, and internal respiration. A machine called a ventilator provides the person air manually by moving air in and out of the lungs when an individual is unable to breathe on their own. The ventilator prevents the accumulation of carbon dioxide so that the lungs don't collapse due to the low pressure. The use of artificial ventilation can be traced back to the seventeenth century. There are three ways of exchanging gases in the body: manual methods, mechanical ventilation, and neurostimulation. Here are some key words used throughout the article. The process of forcing air into and out of the lungs is known as ventilation. The process by which oxygen is taken in by the bloodstream is called oxygenation. Lung compliance is the capacity of the lungs to contract and expand. The obstruction of airflow via the respiratory tract is known as airway resistance. The amount of ventilated air that is not involved in gas exchange is known as dead-space ventilation.

Types

Manual methods

Pulmonary ventilation is done by manual insufflation of the lungs either by the rescuer blowing into the patient's lungs ( mouth-to-mouth resuscitation), or by using a mechanical device. Mouth-to-mouth resuscitation is also part of

cardiopulmonary resuscitation Cardiopulmonary resuscitation (CPR) is an emergency procedure used during Cardiac arrest, cardiac or Respiratory arrest, respiratory arrest that involves chest compressions, often combined with artificial ventilation, to preserve brain function ...

(CPR) making it an essential skill for

first aid First aid is the first and immediate assistance given to any person with a medical emergency, with care provided to preserve life, prevent the condition from worsening, or to promote recovery until medical services arrive. First aid is gener ...

. In some situations, mouth to mouth is also performed separately, for instance in near-

drowning Drowning is a type of Asphyxia, suffocation induced by the submersion of the mouth and nose in a liquid. Submersion injury refers to both drowning and near-miss incidents. Most instances of fatal drowning occur alone or in situations where othe ...

and

opiate An opiate is an alkaloid substance derived from opium (or poppy straw). It differs from the similar term ''opioid'' in that the latter is used to designate all substances, both natural and synthetic, that bind to opioid receptors in the brain ( ...

overdoses. The performance of mouth to mouth on its own is now limited in most protocols to health professionals, whereas lay first aiders are advised to undertake full CPR in any case where the patient is not breathing. This method of insufflation has been proved more effective than methods which involve mechanical manipulation of the patient's chest or arms, such as the Silvester method.

Mechanical ventilation

Mechanical ventilation is a method to mechanically assist or replace spontaneous

breathing Breathing (spiration or ventilation) is the rhythmical process of moving air into ( inhalation) and out of ( exhalation) the lungs to facilitate gas exchange with the internal environment, mostly to flush out carbon dioxide and bring in oxy ...

. This involves the use of

ventilator A ventilator is a type of breathing apparatus, a class of medical technology that provides mechanical ventilation by moving breathable air into and out of the lungs, to deliver breaths to a patient who is physically unable to breathe, or breathi ...

assisted by a

registered nurse A registered nurse (RN) is a healthcare professional who has graduated or successfully passed a nursing program from a recognized nursing school and met the requirements outlined by a country, state, province or similar government-authorized ...

physician A physician, medical practitioner (British English), medical doctor, or simply doctor is a health professional who practices medicine, which is concerned with promoting, maintaining or restoring health through the Medical education, study, Med ...

physician assistant A physician assistant or physician associate (PA) is a type of non-physician practitioner. While these job titles are used internationally, there is significant variation in training and scope of practice from country to country, and sometimes be ...

respiratory therapist A respiratory therapist is a specialized healthcare professional, healthcare practitioner trained in Intensive care medicine, critical care and cardio-pulmonary medicine in order to work therapeutically with people who have acute critical condit ...

paramedic A paramedic is a healthcare professional trained in the medical model, whose main role has historically been to respond to emergency calls for medical help outside of a hospital. Paramedics work as part of the emergency medical services (EMS), ...

, or other suitable person compressing a

bag valve mask A bag valve mask (BVM), sometimes known by the proprietary name Ambu bag or generically as a manual resuscitator or "self-inflating bag", is a hand-held device commonly used to provide Modes of mechanical ventilation, positive pressure ventilation ...

. Mechanical ventilation is termed "invasive" if it involves any instrument penetrating through the mouth (such as an endo tracheal tube) or the skin (such as a

tracheostomy Tracheotomy (, ), or tracheostomy, is a surgical airway management procedure which consists of making an incision on the front of the neck to open a direct airway to the trachea. The resulting stoma (hole) can serve independently as an airway ...

tube). There are two main modes of mechanical ventilation within the two divisions: positive pressure ventilation, where air (or another gas mix) is pushed into the

trachea The trachea (: tracheae or tracheas), also known as the windpipe, is a cartilaginous tube that connects the larynx to the bronchi of the lungs, allowing the passage of air, and so is present in almost all animals' lungs. The trachea extends from ...

, and negative pressure ventilation, where air is, in essence, sucked into the lungs.

Tracheal intubation Tracheal intubation, usually simply referred to as intubation, is the placement of a flexible plastic catheter, tube into the vertebrate trachea, trachea (windpipe) to maintain an open airway or to serve as a conduit through which to administer c ...

is often used for short-term

mechanical ventilation Mechanical ventilation or assisted ventilation is the Medicine, medical term for using a ventilator, ventilator machine to fully or partially provide artificial ventilation. Mechanical ventilation helps move air into and out of the lungs, wit ...

. It's when a tube is inserted through the nose (nasotracheal intubation) or mouth (orotracheal intubation) and advanced into the

. In most cases tubes with inflatable cuffs are used for protection against leakage and aspiration. Intubation with a cuffed tube is thought to provide the best protection against aspiration. Downside of tracheal tubes is the pain and coughing that follows. Therefore, unless a patient is unconscious or anesthetized,

sedative A sedative or tranquilliser is a substance that induces sedation by reducing irritability or Psychomotor agitation, excitement. They are central nervous system (CNS) Depressant, depressants and interact with brain activity, causing its decelera ...

drugs are usually given to provide tolerance of the tube. Other disadvantages of tracheal intubation include damage to the mucosal lining of the

nasopharynx The pharynx (: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the esophagus and trachea (the tubes going down to the stomach and the lungs respectively). It is found in vertebrates and invertebrates, though its ...

oropharynx The pharynx (: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the esophagus and trachea (the tubes going down to the stomach and the lungs respectively). It is found in vertebrates and invertebrates, though its ...

and subglottic stenosis. In an emergency a cricothyrotomy can be used by health care professionals, where an airway is inserted through a surgical opening in the cricothyroid membrane. This is similar to a

but a cricothyrotomy is reserved for emergency access. This is usually only used when there is a complete blockage of the

pharynx The pharynx (: pharynges) is the part of the throat behind the human mouth, mouth and nasal cavity, and above the esophagus and trachea (the tubes going down to the stomach and the lungs respectively). It is found in vertebrates and invertebrates ...

or there is massive maxillofacial injury, preventing other adjuncts being used.

Neurostimulation

A rhythmic pacing of the diaphragm is caused with the help of electrical impulses. Diaphragm pacing is a technique used by persons with spinal cord injuries who are on a mechanical ventilator to aid with breathing, speaking, and overall quality of life. It may be possible to reduce reliance on a mechanical ventilator with diaphragm pacing. Historically, this has been accomplished through the electrical stimulation of a

phrenic nerve The phrenic nerve is a mixed nerve that originates from the C3–C5 spinal nerves in the neck. The nerve is important for breathing because it provides exclusive motor control of the diaphragm, the primary muscle of respiration. In humans, t ...

by an implanted receiver/electrode, though today an alternative option of attaching

percutaneous {{More citations needed, date=January 2021 In surgery, a percutaneous procedurei.e. Granger et al., 2012 is any medical procedure or method where access to inner organs or other tissue is done via needle-puncture of the skin, rather than by using ...

wires to the diaphragm exists.

History

The Greek physician

Galen Aelius Galenus or Claudius Galenus (; September 129 – AD), often Anglicization, anglicized as Galen () or Galen of Pergamon, was a Ancient Rome, Roman and Greeks, Greek physician, surgeon, and Philosophy, philosopher. Considered to be one o ...

may have been the first to describe artificial ventilation: "If you take a dead animal and blow air through its larynx through a reed, you will fill its bronchi and watch its lungs attain the greatest distention."

Vesalius Andries van Wezel (31 December 1514 – 15 October 1564), Latinization of names, latinized as Andreas Vesalius (), was an anatomist and physician who wrote ''De humani corporis fabrica, De Humani Corporis Fabrica Libri Septem'' (''On the fabric ...

too describes ventilation by inserting a reed or cane into the

of animals. It wasn't until 1773, when an English physician William Hawes (1736–1808) began publicizing the power of artificial ventilation to resuscitate people who superficially appeared to have drowned. For a year he paid a reward out of his own pocket to any one bringing him a body rescued from the water within a reasonable time of immersion. Thomas Cogan who was another English physician had become interested in the same subject during a stay at

Amsterdam Amsterdam ( , ; ; ) is the capital of the Netherlands, capital and Municipalities of the Netherlands, largest city of the Kingdom of the Netherlands. It has a population of 933,680 in June 2024 within the city proper, 1,457,018 in the City Re ...

. In the summer of 1774, Hawes and Cogan each brought fifteen friends to a meeting at the Chapter Coffee-house in St Paul's Churchyard, where they founded the Royal Humane Society. Some methods and equipment were similar to methods used today, such as wooden pipes used in the victims nostrils to blow air into the lungs. Or the use of bellows with a flexible tube for blowing tobacco smoke through the anus to revive vestigial life in the victim's intestines, which was discontinued with the eventual further understanding of respiration. The work of English physician and physiologist Marshall Hall in 1856 suggested against the use of any type of bellows/positive pressure ventilation. These views that were held for several decades. The introduction of a common method of external manual manipulation in 1858, was the "Silvester Method" invented by Henry Robert Silvester. A method in which a patient is laid on their back and their arms are raised above their head to aid inhalation and then pressed against their chest to aid exhalation. In 1903, another manual technique, the "prone pressure" method, was introduced by Sir Edward Sharpey Schafer. It involved placing the patient on his stomach and applying pressure to the lower part of the ribs. It was the standard method of artificial respiration taught in Red Cross and similar first aid manuals for decades, until mouth-to-mouth resuscitation became the preferred technique in mid-century. The shortcomings of manual manipulation led doctors in the 1880s to come up with improved methods of mechanical ventilation, which included Dr. George Edward Fell's "Fell method" or "Fell Motor." It consisted of a bellows and a breathing valve to pass air through a

tracheotomy Tracheotomy (, ), or tracheostomy, is a surgical airway management procedure which consists of making an incision on the front of the neck to open a direct airway to the trachea. The resulting stoma (hole) can serve independently as an airway ...

. He collaborated with Dr. Joseph O'Dwyer to invent the Fell-O'Dwyer apparatus, which is a bellows instrument for the insertion and extraction of a tube down the patients

.19th century pioneers of intensive therapy in North America. Part 1: George Edward Fell, Crit Care Resusc. 2007 Dec;9(4):377-9
abstract
/ref> Such methods were still looked upon as harmful and were not adopted for many years. In 2020, the supply of mechanical ventilation became a central question for public health officials due to 2019–20 coronavirus pandemic related shortages.

References

External links

e-Medicine
article on mechanical ventilation along with technical information.

Resource of information for users of home mechanical ventilation.
''Mechanical Ventilation,''
(detailed slideshow presentation), by Amirali Nader, MD FCCP, Critical Care Medicine, Suburban Hospital, Johns Hopkins Medicine. {{Authority control Mechanical ventilation Emergency medicine Intensive care medicine Emergency medical services Respiratory system procedures Respiratory therapy First aid