Risk of infection after ultrasound-guided procedures is low, study suggests

The incidence of serious infection after common ultrasound-guided procedures, such as biopsy, fine-needle aspiration (a form of biopsy) and thoracentesis (procedure involving needle drainage of the chest cavity) is low, according to a study in the October issue of the American Journal of Roentgenology. Ultrasound imaging, also called ultrasound scanning or sonography, involves exposing part of the body to high-frequency sound waves to produce pictures of the inside of the body.

"Ultrasound-guided procedures are safe, effective and accurate in that they utilize real-time imaging and do not use potentially harmful radiation. Given the large number of ultrasound-guided procedures performed annually at our institution and the lack of extensive literature on the incidence of infection after an ultrasound-guided intervention, we decided to conduct a large study to supply data that can be used to better inform patients for consent," said John M. Knudsen, MD, lead author of the study.

Researchers from the Mayo Clinic in Rochester, MN, reviewed 13,534 ultrasound-guided procedures that were performed over a two-year period. "Of the 13,534 procedures, there were only 14 procedure-related infections: 11 were likely related to the procedure and three, possibly related," said Knudsen. The infections consisted of five abscesses, four bloodstream infections, four cases of peritonitis and one urinary tract infection.

"We found that the incidence of a serious infection after ultrasound-guided intervention is low. Nearly all patients with an infectious complication improved on antibiotics alone. Radiologists can use these data to provide more accurate information to patients when asking for consent before procedures and to reassure their patients," said Knudsen.