Diagnosis of Catheter‐Related Infections Tied to Number of Lumens Tested

The conservative diagnosis of catheter-related bloodstream infection (CRBSI) requires the culture of all lumens of all catheters involved, according to a new study.

Researchers at Universidad Complutense de Madrid (Spain) and the Spanish Network of Research in Infectious Diseases (REIPI; Seville, Spain) conducted a retrospective study of 171 episodes of proven CRBSI in 154 patients between January 1, 2003, and May 31, 2009, in patients in which all available catheter lumens (that did not contain clots) were used to draw blood culture samples. The researchers then calculated the number of episodes that would have been missed in double‐ and triple‐lumen catheters, if the culture of samples obtained from one or more lumens had been eliminated.

The results showed that in 112 episodes of proven CRBSI in patients with catheters having only two lumens available, culturing only one of the lumens would have resulted in a missed diagnosis in 27.2% of the CRBSI episodes. Similarly, in 59 episodes of proven CRBSI in patients with triple-lumen catheters, eliminating one lumen would have resulted in a missed diagnosis in 15.8% of episodes; and if the researchers had eliminated two cultures for triple‐lumen catheters, 37.3% of all CRBSI episodes would have been missed. The study was published early online on May 10, 2010, in Clinical Infectious Diseases.

"We recommend culturing all lumens in all cases in which the clinician wishes to preserve and keep the catheter,” said lead author Emilio Bouza, M.D. "In catheters that are going to be withdrawn anyway, there is no need to expend time and resources in those cultures at all.”

"If you want to rule out a multilumen catheter as the cause of an episode of bacteremia using differential cultures, but you draw blood from only a peripheral vein or from only some of the lumens, you will miss the confirmation in a significant number of patients,” added Dr. Bouza.

Health-care institutions purchase millions of intravascular catheters each year; the incidence of CRBSI varies considerably by type of catheter, frequency of catheter manipulation, and patient-related factors, such as underlying disease and acuity of illness. Although the incidence of local or bloodstream infections associated with peripheral venous catheters is usually low, serious infectious complications produce considerable annual morbidity, due to the frequency with which such catheters are used.

Related Links:
Universidad Complutense de Madrid
Spanish Network of Research in Infectious Diseases