Causes of surgical site infections unclear

Bacteria are not always the culprits in post-colic surgery infections at the incision site.

A new study from England suggests that bacterial contamination of nearby skin may not always be the culprit in surgical site infections after colic surgery.

Researchers at the University of Liverpool sampled the skin of the midline from 31 horses for bacterial culture prior to colic surgery, during the procedure and again every 48 hours until the horses were discharged from the hospital. Seven of those horses (22.6 percent) went on to develop surgical site infections after surgery.

However, the researchers found that the presence of bacteria on the skin at midline during or immediately after surgery was not associated with greater likelihood of surgical site infection, nor was the type of bacteria found on the skin. In fact, in the seven horses that did develop a surgical site infection, either no bacteria were identified during surgery or the responsible bacteria were different from the type isolated from the skin during or immediately after surgery. In several horses, no surgical site infection developed despite the detection of bacteria on the incision during or immediately after surgery.

The researchers conclude that development of surgical site infections is not solely related to bacterial contamination of the midline at surgery and recommend further investigation into other possible causes, such as bacteria circulating in the bloodstream.

Originally published in EQUUS 490