The relative contribution of stethoscopes in microbial cross-transmission in comparison to the examiners hands has not been well described. Researchers from Geneva University Hospital in Switzerland endeavored to compare stethoscope versus hand contamination following a physical exam and identify predictors of stethoscope contamination.
Following a standardized physical exam using sterile gloves and a sterile stethoscope, bacterial contamination of the following regions were assessed using contact plates: stethoscope diaphragm, stethoscope tube, fingertips, thenar region, hypothenar region and back of physicians dominant hand. Total aerobic colony count (ACC) were determined on digital photographs using a counting tool.
A total of 56 patients (62 percent males; median age, 66) were recruited. Median (IQR) contamination (in ACC/25cm2) of examiners dominant hand and stethoscope were as follows: fingertips: 835 (IQR, 332-1638), stethoscope diaphragm: 173 (IQR, 36-535), stethoscope tube: 116 (IQR, 34-321), hypothenar region: 16 (IQR, 8-59), thenar region: 15 (IQR, 4-71) and dorsum of hand: 3 (IQR, 1-16). The stethoscope diaphragm and tube were significantly more contaminated than the thenar or hypothenar regions (Wilcoxon ranksum test: p<0.001). There was no difference between the level of tube and diaphragm contamination. Diaphragm contamination was strongly associated with the patients level of skin contamination (p<0.001), the patients BMI (p=0.01) and the degree of humidity of the patients skin (p<0.001).
Schneider, et al. say their results suggest that stethoscopes diaphragm and tube are significantly contaminated following a physical exam and identify predictors of heavy contamination. These findings suggest the need to decontaminate stethoscopes following each use. Their research was presented at the International Conference on Prevention & Infection Control (ICPIC) held in Geneva, Switzerland June 29-July 2, 2011.
Reference: A Schneider, C Tschopp, Y Longtin, G Renzi, A Gayet-Ageron, J Schrenzel, D Pittet. Predictors of stethoscope contamination following a standardized physical exam. Presentation at International Conference on Prevention & Infection Control (ICPIC). BMC Proceedings 2011, 5(Suppl 6):P304
The Sterile Processing Conference Survival Guide: How to Make the Most of Your Next Event
March 25th 2025From expert speakers to cutting-edge tools, sterile processing conferences, like the 2025 HSPA Annual Conference and the SoCal SPA's Spring Conference, offer unmatched opportunities to grow your skills, expand your network, and strengthen your department's infection prevention game.