RT Journal Article
SR Electronic
T1 Microbiological and scanning electron microscopic evaluation of epidural catheters
JF Regional Anesthesia & Pain Medicine
JO Reg Anesth Pain Med
FD BMJ Publishing Group Ltd
SP rapm-2019-101180
DO 10.1136/rapm-2019-101180
A1 Ganapathy van Samkar
A1 Payal P S Balraadjsing
A1 Henning Hermanns
A1 Irene V Hoogendijk
A1 Markus W Hollmann
A1 Sebastian A J Zaat
A1 Markus F Stevens
YR 2020
UL http://rapm.bmj.com/content/early/2020/03/13/rapm-2019-101180.abstract
AB Background Epidural catheters are frequently colonized by gram-positive bacteria. Although the incidence of associated epidural infections is low, their consequences can be devastating. We investigated bacterial growth on epidural catheters by quantitative bacterial culture and scanning electron microscopy (SEM) in order to explore the patterns of epidural catheter colonization.Methods 28 patients undergoing major abdominal surgery with thoracic epidurals (treatment ≥72 hours) were studied. Before the removal of the catheter, the skin surrounding the insertion site was swabbed. The entire catheter was divided into extracorporeal, subcutaneous, and tip segments. Skin swabs and catheter segments were quantitatively cultured, bacterial species were identified, and SEM was performed on four selected catheters.Results 27 of 28 catheters were included. The percentages of positive cultures were: skin swab 29.6%, extracorporeal segments 11.1%, subcutaneous segments 14.8%, and tip segments 33.3%. One patient was diagnosed with a catheter-associated infection. Staphylococcus epidermidis was cultured from the skin and the catheter extracorporeal, subcutaneous, and tip segments. SEM of this catheter showed bacteria-like and intraluminal host cell-like structures. SEM of two other catheters showed intraluminal fibrin networks in their tip segments.Conclusions We present the first SEM pictures of an epidural catheter with a bacterial infection. Bacterial growth developed from the skin to the tip of this catheter, indicating the skin as a primary source of infection. By SEM, catheters with low levels of bacterial growth demonstrated an intraluminal fibrous network which possibly plays a role in catheter obstruction.