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Contamination of stethoscopes and physicians' hands after a physical examination
Yves Longtin1, Alexis Schneider1, Clément Tschopp1
1Infection Control Program and WHO Collaborating Centre on Patient Safety, University of Geneva Hospitals, Geneva, Switzerland; Faculty of Medicine, University of Geneva, Geneva, Switzerland.
Objectives:
To compare the contamination level of physicians' hands and stethoscopes and to explore the risk of cross-transmission of microorganisms through the use of stethoscopes.
Patients And Methods:
We conducted a structured prospective study between January 1, 2009, and May 31, 2009, involving 83 inpatients at a Swiss university teaching hospital. After a standardized physical examination, 4 regions of the physician's gloved or ungloved dominant hand and 2 sections of the stethoscopes were pressed onto selective and nonselective media; 489 surfaces were sampled. Total aerobic colony counts (ACCs) and total methicillin-resistant Staphylococcus aureus (MRSA) colony-forming unit (CFU) counts were assessed.
Results:
Median total ACCs (interquartile range) for fingertips, thenar eminence, hypothenar eminence, hand dorsum, stethoscope diaphragm, and tube were 467, 37, 34, 8, 89, and 18, respectively. The contamination level of the diaphragm was lower than the contamination level of the fingertips (P<.001) but higher than the contamination level of the thenar eminence (P=.004). The MRSA contamination level of the diaphragm was higher than the MRSA contamination level of the thenar eminence (7 CFUs/25 cm(2) vs 4 CFUs/25 cm(2); P=.004). The correlation analysis for both total ACCs and MRSA CFU counts revealed that the contamination level of the diaphragm was associated with the contamination level of the fingertips (Spearman's rank correlation coefficient, ρ=0.80; P<.001 and ρ=0.76; P<.001, respectively). Similarly, the contamination level of the stethoscope tube increased with the increase in the contamination level of the fingertips for both total ACCs and MRSA CFU counts (ρ=0.56; P<.001 and ρ=.59; P<.001, respectively).
Conclusion:
These results suggest that the contamination level of the stethoscope is substantial after a single physical examination and comparable to the contamination of parts of the physician's dominant hand.
Insights
Physicians' stethoscopes become significantly contaminated with microorganisms after patient examinations, posing a risk for cross-transmission. This study found stethoscope contamination levels comparable to physicians' hands, highlighting the need for improved hygiene practices.
Area of Science:
- Medical Microbiology
- Infection Control
- Clinical Research
Background:
- Physicians' stethoscopes are frequently used medical devices.
- The potential for stethoscopes to harbor and transmit microorganisms is a concern for patient safety.
- Understanding stethoscope contamination is crucial for preventing healthcare-associated infections.
Purpose of the Study:
- To quantify and compare microbial contamination levels on physicians' hands and stethoscopes.
- To assess the risk of microorganism cross-transmission via stethoscopes.
- To evaluate the association between hand and stethoscope contamination.
Main Methods:
- Prospective study involving 83 inpatients at a Swiss university hospital.
- Sampling of 4 hand regions and 2 stethoscope sections after standardized examinations.
- Assessment of total aerobic colony counts (ACCs) and methicillin-resistant Staphylococcus aureus (MRSA) colony-forming units (CFUs).
Main Results:
- Stethoscope diaphragms showed significant contamination with ACCs and MRSA.
- Diaphragm contamination was lower than fingertips but higher than the thenar eminence.
- Stethoscope contamination levels strongly correlated with fingertip contamination.
Conclusions:
- Stethoscopes acquire substantial microbial contamination after a single patient examination.
- Stethoscope contamination levels are comparable to those found on physicians' hands.
- Findings underscore the role of stethoscopes in potential microorganism cross-transmission.
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