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Hospital-Acquired Infections


Oren Traub

, MD, PhD, Pacific Medical Centers

Last full review/revision Mar 2018| Content last modified Mar 2018

People who are admitted to the hospital are at risk of acquiring an infection there. Such infections are called nosocomial infections. In the United States, about 4-5% of people who are hospitalized get a nosocomial infection, and about 75,000 of these people die each year. (See also Problems Due to Hospitalization.)

The risk of infection is higher for

  • Infants
  • Older people
  • People with a weakened immune system

Nosocomial infections may be caused by bacteria or fungi. Bacterial and fungal infections can be dangerous and deadly.

Organisms that are acquired in hospitals are often resistant to many common antibiotics. The frequent use of antibiotics in hospitals encourages resistant strains to develop.

Hospital-acquired infections include pneumonia, urinary tract infections, infection of surgical incisions, and blood infections.

Lung infections

People who stay in bed do not use their lungs as much, and the muscles that control breathing may weaken. Then, taking a deep breath may become difficult, and if mucus accumulates in the airways, people may not be able to cough forcefully enough to clear the mucus out. When mucus accumulates, bacteria cannot be cleared from the airways very well, and pneumonia may develop.

The risk of lung infections is increased by the following:

  • Using a ventilator, which makes the risk very high
  • Having had antibiotic treatment previously
  • Having other disorders, such as heart, lung, liver, or kidney disorders
  • Being older than 70
  • Living in a nursing home
  • Having had abdominal or chest surgery
  • Taking certain medications such as proton pump inhibitors, which reduce stomach acid

Deep breathing and coughing exercises can help prevent lung infections. These exercises can help keep the lungs open and prevent breathing muscles from weakening.

Urinary tract infections

Sometimes people in the hospital have a drainage tube placed in their bladder (urinary catheter). A catheter may be inserted when doctors need to closely monitor how much urine people produce—for example, in those who are critically ill. In the past, doctors placed urinary catheters in people who were incontinent. However, catheters significantly increase the risk of a urinary tract infection because they make it easy for bacteria to enter the bladder.

Thus, to prevent urinary tract infections, doctors try to use these catheters as seldom as possible. When catheters are used, they must be carefully cleaned and regularly examined. If people are incontinent, diapers that are changed as often as needed are a better choice than a urinary catheter.

Prevention of Hospital-Acquired Infections

General measures that hospital staff members use to help prevent hospital-acquired infections include the following:

  • Frequent hand washing
  • Frequent use of alcohol-based hand sanitizers
  • Use of protective gear such as gloves and gowns when procedures are done

To prevent development of resistant bacteria, many hospitals have programs to limit the use of antibiotics so that only people with proven infections receive them. Also, many hospitals limit the use of the newest and most powerful antibiotics to prevent resistance from developing.

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