Etude n°4

• 4. Ineffectiveness of latex condoms in preventing contamination of the transvaginal ultrasound transducer head

En conditions d’examens (173 patientes), 5% des préservatifs recouvrant la sonde d'échographie vaginale ont laissé passer les liquides biologiques de la patiente à la sonde (test H2O2). Sur ces 8 cas, seulement 3 se sont manifestés par une contamination visible de la sonde.

L'efficacité des préservatifs pour éviter la contamination de la sonde, et potentiellement celle des patientes, était inconnue. Cette étude montre l'inefficacité des préservatifs à jouer ce rôle, ainsi que l'inefficacité du contrôle visuel pour identifier les contaminations. Ceci suggère que des mesures supplémentaires soient mises en oeuvre pour éviter la transmission d’infections.

The efficacy of condoms in preventing contamination of the transvaginal ultrasound transducer head and possible transmission of blood-borne pathogens is unknown. The authors' objective was to determine the rate of contamination of the transvaginal ultrasound probe after use in the emergency department. After indicated transvaginal ultrasound scans, the latex condom was removed and the transducer head was inspected for contamination. The presence of vaginal bleeding and the duration of the ultrasound scan were noted. 10 ml of hydrogen peroxide (H2O2) was placed in the condom. Bubbling, which occurs in the presence of blood or cervicovaginal secretions, was considered a positive test. Exposure of a clean condom or coupling gel to H2O2 did not cause bubbling. Two-tailed Fisher's Exact and Student's t tests were used for statistical analysis. Of 173 cases, 8 (5%) had a positive H2O2 test for contamination. In only 3 of these 8 cases was gross contamination seen. Latex condoms are ineffective in preventing contamination of the transvaginal ultrasound transducer head. Visual inspection of the transducer head often fails to identify the presence of blood or body fluids. This suggests that additional measures should be taken to prevent transmission of blood-borne pathogens.