Bacterial contamination and cleanliness of emergency department ultrasound probes

Abstract

Objectives: As ultrasonography is increasingly used in the emergency department (ED), ultrasound equipment has become a potential threat to infection control. Improperly cleaned ultrasound probes may serve as a vector for pathogens such as methicillin-resistant Staphylococcus aureus (MRSA). The primary objective of this study was to determine the prevalence of MRSA colonization on ultrasound probes used in a busy, urban ED. It was hypothesized that cultures of our ED ultrasound probes would yield a significant number of positive results for MRSA. Methods: In this observational study, 11 ED ultrasound probes were randomly sampled on 10 different occasions. Samples were taken using a RODAC plate method and were cultured for MRSA and methicillin-sensitive Staphylococcus aureus (MSSA). On half of the randomly assigned sampling occasions, a visual inspection of each ultrasound probe for general cleanliness was conducted and recorded. Data were stratified by ultrasound location in the ED and analyzed using the Fisher exact test, with p , 0.05 deemed to be statistically significant. Results: Of 110 samples, no isolates of MRSA were cultured. One probe yielded a positive culture for MSSA. Probes in the medicine, trauma, and pediatrics areas were found to be clean 65%, 33%, and 70% of the time, respectively. This variability in probe cleanliness by ED location was found to be statistically significant (p , 0.01). Conclusions: Contrary to our hypothesis, MRSA contamination of ultrasound probes was not found. This finding suggests that the spread of MRSA by ED ultrasound machines in a high-volume urban ED is unlikely. Further research at different centres with larger sample sizes is required before these results can be generalized. RÉ SUMÉObjectifs : Les services des urgences (SU) utilisent de plus en plus l'é chographie; or, ces appareils sont devenus des menaces potentielles dans la lutte contre l'infection. Des sondes é chographiques mal nettoyé es peuvent en effet servir de vecteurs aux pathogè nes comme le Staphylococcus aureus ré sistant à la mé thicilline (SARM). Cette é tude avait donc comme principal objectif de dé terminer la pré valence de colonisation par le SARM des sondes é chographiques utilisé es dans un SU en milieu urbain à grande affluence. On a é mis l'hypothè se que des cultures des sondes é chographiques du SU donneraient un nombre important de ré sultats positifs quant au SARM. Mé thodes : Dans cette é tude par observation, onze sondes é chographiques ont é té é chantillonné es au hasard en dix occasions diffé rentes. Les é chantillons ont é té pré levé s au moyen de la mé thode en boîte Rodac et cultivé s afin d'y dé tecter la pré sence de SARM et de SASM (Staphylococcus aureus sensibles à la mé thicilline). Lors de la moitié des é chantillonnages au hasard, une inspection visuelle de la propreté globale de chaque sonde é chographique a é té mené e et consigné e. Les donné es ont é té stratifié es par site d'é chographie au SU et analysé es au moyen de la mé thode exacte de Fisher, où p , 0,...

Infection Prevention in the Emergency Department

“…173 With appropriate disinfection practices using antimicrobial wipes, contamination of ultrasonographic probes with MRSA remains uncommon. [173][174][175] Transvaginal ultrasonography has been used in the ED to evaluate complaints of vaginal bleeding and pelvic pain, as well as to diagnose early intrauterine pregnancy. In one study, human papillomavirus (HPV) contamination of transvaginal, or endocavitary, probes using polymerase chain reaction (PCR) was identified in 7.5% of surveillance samples.…”

Evaluation of emergency department ultrasound machines for the presence of occult blood

“…The risk of transmitting a virus through ultrasound procedures is possible 4 ; however, we did not attempt to look for the presence of any blood borne viruses from the samples, because this was not within the scope of this study. Occult blood has been shown to be present on medical equipment that contacts patients, 5 and ultrasound probes have been shown to be contaminated with visible blood, used gel, 6 and bacteria. 7 Although ours is a small study, we feel it adds to the literature that highlights the importance of ultrasound cleaning in the ED.…”

“…5 The incidence of occult blood contamination of ultrasound machines is not known; however, the presence of visible contamination and bacterial colonization has been shown. 6,7 Therefore, the primary goal of this study is to evaluate the trauma centre ED ultrasound machine for the presence of occult and visible blood contamination after routine daily use and its use in traumas.…”

Does the Use of Ultrasound Affect Contamination of Musculoskeletal Injections Sites?

“…Several studies have investigated contamination and cleanliness of ultrasound probes in various clinical settings and found that bacterial colonization was common [11,14,18,25]. These authors recommended several different cleaning techniques, of which wiping the probe with a nonsterile towel alone or in combination with alcohol wipes were most frequently suggested [11,18].…”