Pneumonia is a broad term for an infection that causes lung inflammation. Much like urinary tract infections, pneumonia occurs when bacteria or viruses get into the lower respiratory system, which is usually sterile. Your body has built-in defenses against pathogens getting into the respiratory system, such as the chemicals in your saliva, the cough reflex and the mechanical barriers, like the cilia in your nose.
Unfortunately, many medical conditions and treatments can weaken or bypass these defenses. Feeding tubes, brain damage, lack of consciousness and prolonged periods spent lying down all can increase the risk of a patient getting pneumonia. Any pneumonia contracted in a hospital is known as a hospital-acquired pneumonia, or HAP [source: APIC].
Ventilator-associated pneumonia, or VAP, represents a specific type of pneumonia contracted through an intubation tube and ventilator. Someone on a ventilator is often subject to many of the factors that can lead to pneumonia, and if the ventilator apparatus itself is not kept sterile, it magnifies the problem. As with the other tubes we've mentioned, a breathing tube can act as a highway for bacteria to travel straight into the lungs, bypassing most of the body's defenses. Patients in intensive care trauma wards are at especially high risk.
Prevention requires several steps on the part of hospital workers, beginning with washing hands thoroughly and wearing protective gloves when touching the mouth and nose of a patient. Daily antibacterial agents like chlorhexidine can be used to rinse the mouth [source: Critical Care Nurse].