Author: Marie Rosenthal, MS

Anesthesiology News

Those little rubber tourniquets used while drawing blood could put patients at risk, because they appear to be contaminated with a variety of disease-producing organisms, according to research presented at the 2019 annual European Congress of Clinical Microbiology and Infectious Diseases (poster 1044).

Tourniquets are one of the most widely used and reused items in health care. They are typically used during peripheral venipuncture—the most frequently performed invasive procedure in health care settings—to make it easier to administer IV injections, collect blood samples, or perform other procedures.

Dr. Osório and her team considered both published and unpublished studies written in English, French, Spanish and Portuguese up to December 2017. After a detailed analysis, they were left with 20 clinical studies with a combined total sample size of 1,479 tourniquets. Contamination rates varied from 10% to 100%, with coagulase-negative staphylococci found most often—present on 441 of the tourniquets analyzed. Coagulase-negative staphylococci can cause a range of infections, including skin and soft tissue infections.

They also found contamination by other species of bacteria including Escherichia coli, Enterococcus, Klebsiella, Pseudomonas, Acinetobacter baumannii and Stenotrophomonas maltophilia. They found individual contamination rates of up to 10% for each species. These organisms cause a range of potentially serious illnesses, such as pneumonia, and represent a particular risk to immunocompromised patients or those with chronic illnesses, such as cystic fibrosis.

Dr. Osório said in an interview that she was not surprised to see the staph, because it is a normal skin flora. “However, these results highlighted failures in the decontamination and asepsis of these medical devices that are frequently used in invasive procedures, specifically to take blood or for peripheral IV catheterization.

Another concern was that “the majority of the Staphylococcus found in the major articles also present methicillin resistance. Methicillin-resistant Staphylococcus aureus are one of the several species involved in health care–associated infections,” she said.

And the rates were quite high. In 15 of the studies, contamination rates were higher than 70% of the tourniquets analyzed. These data reiterate the inherent risks that reusable tourniquets can pose to patients, related to the potential dissemination of microorganisms between patients through this medical device, the researchers said.

“The purpose of our work is only to map the scientific evidence relative to the microbiological contamination in the tourniquets, rate, species and antibiotic resistance in the species found,” she said. “However, if we used these medical devices in invasive procedures, the risks of contamination increase, and maybe for this we have some cases of phlebitis, bacteremia and sepsis related to catheter insertions, for example.”

More research should be conducted to find the best method for decontaminating tourniquets that are reused or to see whether single-use, disposable tourniquets should be used in clinical settings.

Dr. Osório called the tourniquets very useful medical devices that are fundamental to the provision of health care, so the costs involved in ensuring aseptic procedures or in switching to disposable devices would be lower than dealing with a hospital-acquired skin or bloodstream infection that would increase the length of stay.