Mechanical Ventilation
Machine-assisted Breathing

Respiratory failure is a life-threatening condition in which the body's respiratory apparatus is unable to provide adequate delivery of oxygen to the blood and removal of carbon dioxide from the blood. It is an unstable condition, and if untreated, further deterioration and eventual respiratory arrest (i.e., the complete cessation of effective breathing) are more likely than improvement.

Severely impaired respiratory function and eventual respiratory failure may result from airway obstruction, inadequacy of the ventilatory muscles, lung disease, or chest injury, as well as from a variety of cardiac, neurological, and neuromuscular disorders. The most common causes--asthma and COPD (chronic obstructive pulmonary disease)--are primarily diseases of older people. In addition, other conditions associated with the risk of respiratory failure, including pneumonia, sepsis, and pulmonary edema, are more likely to result in respiratory failure when the person is elderly.

Loss of spontaneous breathing is accompanied by loss of the ability to communicate, eat, and move. Illness and institutionalization bring loss of social roles, loss of accustomed life style, loss of positive body image and self-image, loss of privacy, and general loss of independence.

For elderly patients, ventilator-related losses come at a time when other serious losses--retirement, income, social status, friends, or spouse--are accumulating. The ventilator patient's greatest psychological problem is the lack of control, the inability to do anything for oneself or for anyone else.

However, for those suffering severe impairment or even complete failure of respiratory function, the ventilator (or "respirator," as the device is better known) is literally the link between life and death. Mechanical ventilation can effectively assist or replace normal spontaneous breathing by taking over the vital role of the respiratory muscles, inducing rhythmic inflation and emptying of the lungs. It also must provide the natural processes of humidification, filtration, and the warming of inspired gases if the intubation (use of an inserted tube) ventilation is employed.

Mechanical ventilation is the use of a machine to induce alternating inflation and deflation of the lungs, to regulate the exchange rate of gases in the blood. The most common type of ventilator (or respirator) delivers inspiratory gases directly into the person's airway. The patient is connected to the ventilator by a endotracheal tube passed through the nose or mouth into the trachea (windpipe). If prolonged ventilation is likely to be required, a tube is inserted into an opening made in the trachea, an operation called a tracheostomy. Conscious patients, and those nearing the end of anesthesia, are usually given muscle-relaxant and sedative drugs to prevent them from resisting the insertion and irritant presence of the tube. The technology is used to sustain persons whose spontaneous breathing is inadequate or has stopped altogether due to acute or chronic diseases of the neuromuscular, neurologic, or pulmonary system, or due to anesthesia, trauma or high-risk surgical procedures. For ventilator patients who do not need to be confined to bed, portable ventilators allow mobility and a variety of physical activities.

A person's experience of severe respiratory impairment and treatment with mechanical ventilation, as with other life-threatening illness and treatment, depends on a variety of personal and environmental factors. Among the most important are the person's personality, prognosis, level of consciousness, social support, the quality and sensitivity of the care received, and treatment setting. Some individuals cope better or worse with the physical, psychological, and social stresses to which they are subjected.

In the care of many acutely ill patients, mechanical ventilation lasting only hours or a few days is sufficient and the ventilator can be removed and normal breathing resumes. Unfortunately, for those whose underlying disease is chronic or irreversible, can become, sometimes unexpectedly, chronically ventilator dependent. Their continuing need for mechanical ventilation may be total, i.e., 24-hours a day, or it may be limited, i.e., only during sleep or intermittently through the day.

Mechanical ventilation is a mixed blessing as it's potential good is not always good enough. While offering hope of prolonged life, mechanical ventilation has drastic implications for the quality of life. Whether a particular individual will benefit from mechanical ventilation is initially a medical judgement. Often, however, no clear diagnosis has been established, and even when one has, the individual's prognosis may remain highly uncertain. The patient, family members, physicians, nurses, and other professional caregivers may not agree with each other on the prognosis and thus, the decisonmaking reverts from the medical expertise to the realms of psychology, ethics, religion, economics, and law. Furthermore, the costs associated with this technology is enormous. So, for severely ill patients, their families, and those required to make healthcare decisions, the long-term use of this technology can be the source of considerable anguish.