Risk of nosocomial bacteria transmission: Evaluation of cleaning methods of probes used for routine ultrasonography
West African Journal of Medicine
Department of Radiology, Ladoke Akintola University Teaching Hospital, Osogbo, Nigeria; Department of Medical Microbiology, Ladoke Akintola University Teaching Hospital, Osogbo, Nigeria; Department of Chemical Pathology, Ladoke Akintola University Teachin
Background: There exists a small but definite risk of nosocomial infection transmission attributable to ultrasonography probes and coupling gels. Objective: Our objective was to ascertain whether the current method of probe disinfection in between patients is adequate to prevent cross infection, and to determine the best and safest method of probe disinfection applicable during routine ultrasonography in our institution. Materials and method: Forty consecutive patients sent for routine ultrasonography at the Radiology Department of our institution in the month of January 2004 were studied. Each patient had a standardized ultrasound scan of the abdomen, after which swabs were taken from the surface of the unclean probe and after probe disinfection by single and double paper wipe cleaning method. The swabs were cultured on Blood agar to determine the characteristics of the colony forming units (CFU). Result: Forty four bacterial isolates were recovered from 37 patients who cultured positive, with MRSA constituting 36.4 %, MRCONS 22.7 %, MSSA 13.6 %, MSCONS 13.6 %, Klebsiella spp 9.1 % and Proteus mirabilis 4.6 %. The average CFU transmitted by the unclean probe was significantly higher (P<0.05) than that transmitted by the probe after single or double paper wipe. Also, the average CFU transmitted following single and double paper wipe, in the inpatients was significantly higher (P<0.05) than in the outpatients. Conclusion: Single paper wipe is adequate for outpatients, but for inpatients, especially those with high risk of cross infection, double paper wipe is preferred with probe thoroughly wiped until visibly clean.
article; bacterial colonization; bacterial infection; bacterium isolate; cleaning; clinical article; clinical protocol; coagulase negative Staphylococcus; colony forming unit; controlled study; culture medium; disease transmission; disinfection; echography; hospital hygiene; hospital infection; human; infection risk; instrument sterilization; Klebsiella; methicillin resistant Staphylococcus aureus; Proteus mirabilis; statistical analysis; statistical significance; Abdomen; Bacterial Infections; Cross Infection; Disinfection; Equipment Contamination; Gels; Humans; Nigeria; Radiology Department, Hospital; Risk Factors; Ultrasonography