Hospital-acquired pneumonia is an infection of the lungs contracted during a hospital stay.

Nosocomial pneumonia; Ventilator-associated pneumonia

Pneumonia is a very common illness. It is caused by many different germs and can range in seriousness from mild to life-threatening.

Hospital-acquired pneumonia tends to be more serious, because a patient's defense mechanisms against infection are often impaired during a hospital stay. In addition, the types of germs present in a hospital are frequently more dangerous than those encountered in the community. Hospital-acquired pneumonia occurs more commonly in patients who require a respirator to help them breathe. It is also known as ventilator-associated pneumonia.

Risk factors for hospital-acquired pneumonia include:

• Alcoholism
• Being on a breathing machine
• Immunosuppression from medications or disease
• Inhaling material into the lungs (aspiration)
• Older age
• Recent illness

• Cough that may produce mucus-like, greenish, or pus-like sputum
• Chills
• Shortness of breath
• Fever
• Easy fatigue
• Sharp or stabbing chest pain that gets worse with deep breathing or coughing
• Headache
• Loss of appetite
• Nausea and vomiting
• General discomfort, uneasiness, or ill feeling (malaise)
• Joint stiffness and joint pain (rare)
• Muscle stiffness (rare)
• Excessive sweating (rare)

A physical examination reveals respiratory distress and crackles or decreased breath sounds when listening to the chest with a stethoscope.

Tests performed may include:

• Chest x-ray or CT scan
• Sputum gram stain
• Sputum culture
• Blood cultures
• CBC (complete blood cell count)
• Arterial blood gases