Pneumonia most common infection after heart surgery

Pneumonia - not a deep incision surgical site infection - is the most common serious infection after heart surgery, according to new research (Abstract 12247) presented at the American Heart Association's Scientific Sessions 2011.

The study also revealed that most infections occur about two weeks after surgery, not one week as physicians previously thought.

"It's not what we expected to find," said Michael A. Acker, M.D., the study's lead researcher and professor and chief of cardiovascular surgery at the University of Pennsylvania Medical Center in Philadelphia, Pa.

In abstract 12247, researchers analyzed more than 5,100 patients in a heart surgery registry. Patients, average age 64, were treated at nine U.S. academic medical centers and one Canadian center. The median time to major infection was 14 days after heart surgeries. Forty-two percent of all major infections occurred after hospital discharge.

"Half of these patients had no evidence of infection before they were discharged from the hospital," Acker said. "Then they had to return because of the new infection. One implication is that patients must be followed more closely after discharge."

In this study, which excluded patients who were infected before surgery, researchers found 742 infections: 278 were classified as major infections (occurring in 4.5 percent of patients) and 464 were minor (in 8.1 percent of patients). Of the major infections:

Pneumonia, infection of the lungs, occurred in 2.4 percent of all patients.
C. difficile colitis, an intestinal infection, occurred in 1.0 percent.
Bloodstream infections occurred in 0.7 percent.
Deep-incision surgical site infections occurred in 0.5 percent.

Minor infections included urinary tract and superficial incision site infections.

The most commonly performed procedures were isolated coronary artery bypass graft and aortic and mitral valve surgeries. Seventy-four percent were elective surgeries and 26 percent were non-elective or emergency surgeries.

Pneumonia is an inflammation of the lung, usually caused by an infection. Three common causes are bacteria, viruses and fungi. You can also get pneumonia by accidentally inhaling a liquid or chemical. People most at risk are older than 65 or younger than 2 years of age, or already have health problems.

If you have pneumonia, you may have difficulty breathing and have a cough and a fever. A physical exam and history can help determine if you have pneumonia. Chest x-rays and blood tests can help determine what is wrong. Treatment depends on what made you sick. If bacteria are the cause, antibiotics should help. Viral pneumonia may get better with rest and drinking liquids.

Preventing pneumonia is always better than treating it. The best preventive measures include washing your hands frequently, not smoking, and wearing a mask when cleaning dusty or moldy areas. There is a vaccine for pneumococcal pneumonia, a bacterial infection which accounts for up to a quarter of all pneumonias.