JUL 29, 2016

Predicting Risk of Pneumonia After Heart Surgery

WRITTEN BY: Kara Marker
A new study of over ten thousand heart surgery patients led to the collection of 17 patient characteristics that scientists believe will be the best-ever prediction tool kit for postoperative pneumonia, which occurs in 3.3 percent of open-heart surgery patients. Postoperative pneumonia is the most common infection to occur after this procedure, and it is directly correlated with longer hospital stays and a lower chance of survival.
There are over 30 causes of pneumonia: bacteria, viruses, mycoplasmas, fungi, and various chemicals just to name a few. Because of the high prevalence of this infection for patients undergoing heart surgery, scientists believe their new preoperative risk model presents significant preventative strategies that will help doctors and patients decide when the best time for surgery truly is. 

From the University of Michigan Health System, researchers analyzed data from over 16,000 patients who underwent coronary artery bypass graft (CABG) surgery. The list of 17 patient characteristics that resulted from their study will hopefully be implemented soon to help people decide how to prepare their bodies for surgery or know when to postpone surgery to create the best chance they have at a successful surgery and a healthy recovery.

“This work reflects an evolution of our understanding of postoperative infections and can go a long way to preserve resources and help patients recover from one of the country’s most common cardiac procedures,” said senior study author Donald Likosky, PhD, an associate professor of cardiac surgery at the University of Michigan Medical School.

Among the patient characteristics considered to put patients at risk for postoperative pneumonia are age, race, smoking habits, and white blood cell count. From their study, researchers believe that an elevated white blood cell count indicates a patient’s immune system is revving up in preparation to fight an infection, making them vulnerable even before beginning CABG surgery, which could further weaken their body’s ability to recuperate.

Additionally, while researchers noted that a history of smoking increases a heart surgery patient’s risk for postoperative pneumonia, they also observed that quitting even a month before the procedure has a significant impact on their health outcome. 

Lastly, the researchers saw that patients undergoing emergency heart surgery, those with a history of lung problems, those who have been in the hospital for a long time before their surgery, and those with a low ejection fraction are also at a higher risk for postoperative pneumonia. While these conditions usually can’t be avoided or reversed, the researchers believe that it is important for both the doctor and the patient to consider the risks before continuing with surgery.

With a whole new set of tools to help doctors and patients make better decisions about heart surgery, researchers from this study are hoping medical professionals will be fully equipped to be as “vigilant” as ever both before and after open-heart surgery.

This study was recently published in the journal the Annals of Thoracic Surgery
 


Sources: University of Michigan Health System, American Lung Foundation