Artificial respiration, also known as assisted breathing or artificial ventilation, is a procedure used to support or stimulate a person’s breathing when natural respiratory function is insufficient or has stopped. This intervention involves manually or mechanically moving air into and out of the lungs. The fundamental purpose is to restore gas exchange, ensuring oxygen is delivered to the bloodstream and carbon dioxide is removed.
Why Artificial Respiration is Necessary
The body relies on a constant supply of oxygen to fuel cellular processes; the brain can suffer irreversible damage in as few as four to six minutes without it. Respiratory failure occurs when the lungs cannot perform adequate gas exchange, leading to a dangerous drop in blood oxygen levels (hypoxemia) and a buildup of carbon dioxide (hypercarbia).
A variety of sudden events can cause breathing to cease or become severely depressed, triggering the need for artificial respiration. Common emergencies include near-drowning, severe airway obstruction, or sudden cardiac arrest where the respiratory drive is lost. Opioid overdose or certain neurological injuries can also suppress the brain’s ability to signal the diaphragm and chest muscles to breathe. Providing prompt assisted breathing buys valuable time until the underlying issue can be addressed.
Methods of Manual Respiration
Manual respiration involves immediate, non-device-dependent first-aid techniques performed by a rescuer to move air into the victim’s lungs. The most widely taught method for emergency situations is mouth-to-mouth resuscitation, often delivered as rescue breaths within Cardiopulmonary Resuscitation (CPR). Before delivering a breath, the rescuer must ensure the airway is open, typically using a head-tilt/chin-lift maneuver to move the tongue away from the back of the throat.
To perform rescue breathing, the rescuer pinches the victim’s nostrils shut, creates an airtight seal over the victim’s mouth, and delivers a breath lasting about one second, causing the chest to visibly rise. Allowing the chest to fall naturally permits passive exhalation before the next breath is given. These rescue breaths are integrated into the sequence of chest compressions during CPR, typically using a 30:2 compression-to-breath ratio when cardiac arrest is suspected.
The air exhaled by the rescuer contains approximately 16% oxygen, which is sufficient to sustain the victim’s oxygenation temporarily. Historical methods involving manipulating the victim’s body position are rarely used today due to the superior effectiveness of direct positive-pressure ventilation. The simplicity and immediate availability of mouth-to-mouth resuscitation make it a foundational component of emergency life support.
Mechanical Respiration in Clinical Settings
When patients require prolonged or highly controlled respiratory support, specialized equipment is used for mechanical respiration in clinical environments. This approach utilizes a ventilator, a machine that generates positive pressure to push controlled volumes of air into the patient’s lungs. The machine is programmed to deliver a set tidal volume and respiratory rate, ensuring precise gas exchange and preventing the air sacs (alveoli) from collapsing.
Mechanical ventilation is broadly categorized into non-invasive and invasive support, depending on the method of airway connection. Non-invasive ventilation (NIV) employs a tightly fitted mask, such as Continuous Positive Airway Pressure (CPAP) or Bi-level Positive Airway Pressure (BiPAP), over the nose and mouth. This method is often used for conscious patients with conditions like severe chronic obstructive pulmonary disease (COPD) or sleep apnea, where it provides support without the need for an internal tube.
Invasive mechanical ventilation is reserved for patients unable to protect their airway or requiring maximum respiratory support, such as during major surgery or critical illness. This method involves inserting an endotracheal tube (ETT) into the trachea, or using a tracheostomy, creating a direct connection between the ventilator and the lungs. Ventilator settings, including Positive End-Expiratory Pressure (PEEP), are carefully managed by medical staff to optimize oxygen delivery while minimizing potential lung injury.