Surgical site infections often caused by preexisting bacteria

Editor's Note

Most healthcare-associated surgical site infections are not caused by pathogens acquired in the hospital, but by previously harmless bacteria already present on patients’ skin prior to being admitted, according to a study published April 10 in Science Translational Medicine.

Surgical site infections account for the highest annual costs of any hospital-acquired infections—over 33% of $9.8 billion spent—and they are a significant driver of hospital readmissions and death, the researchers write. Despite extensive precautions taken to prevent infections, such as sterilization of surgical equipment, airflow monitoring, and proper surgical attire, surgical site infections still occur in about 1 in 30 procedures. There has been little improvement in these numbers, despite improvements in other medical complications. 

The recent study focused on spinal surgery, which impacts men and women about equally, requires more resources than other types of surgeries, and carries risk of post-surgery infections that can have devastating outcomes. Researchers sampled bacteria from the nose, skin and stools of over 200 patients prior to spinal surgery over the course of a year. They discovered that 86% of the bacteria causing infections after spine surgery matched bacteria a patient carried before surgery. Additionally, nearly 60% of infections were resistant to antibiotics and antiseptics used to prevent infection prior to and during surgery due to prior exposure to these products.

These findings point to a need to shift the focus to a more patient-centered approach to preventing infections, researchers conclude.