1. Running head: THE DIFFERENCE IN STETHOSCOPE CONTAMINATION 1
The Difference Between Physician and
Nurse Stethoscope Contamination: A Literature Review
Jessica Bryan
Azusa Pacific University
Author Note
Jessica Bryan, Department of Nursing, Azusa Pacific University.
This paper was prepared for the Graduate Nursing Seminar 507, Scientific Writing course,
taught by Professor Corinne McNamara and reviewed by the Writing Center.
2. THE DIFFERENCE IN STETHOSCOPE CONTAMINATION 2
The Difference Between Physician and Nurse Stethoscope Contamination: A Literature Review
Concern over hospital-acquired infections (HAI's) has risen amongst healthcare providers
because of poor disinfection practice of stethoscopes. Pathogenic bacteria, such as Staphylococcus
aureus (S. aureus), Escherichia Coli (E. Coli), and Methicillin Resistant Staphylococcus aureus
(MRSA), have potential to transfer onto stethoscope surfaces once skin contact is established with
an infected patient and pose a severe threat to patients’ health. These kinds of pathogenic bacteria
are known to cause serious illness or death if the patient is immunocompromised, critical, or for
patients with compromised barriers, such as wounds, surgical sites, and ulcers (Whittington,
Whitlow, Hewson, Thomas, & Brett, 2009). Amongst healthcare workers in the hospital setting,
physicians and nurses more commonly use stethoscopes on a regular basis for assessing patients to
provide quality care. Both careers see multiple patients daily; however a physician would see
patients by the dozens during each shift. With the high volume of patient interaction, controlling
the rate of transmitting pathogens from stethoscope to patient is a concern for the prevention of
HAI's. Distinguishing if there is a difference in the severity of stethoscope contamination between
physicians or nurses will establish which workforce is more likely to pose the higher risk for
spreading harmful pathogens to patients, follow evidence based practice for disinfecting
techniques, and aide in the efforts to improve disinfecting practices in the hospital setting. Five
peer-reviewed articles will be discussed to identify if there is a difference and what can be
recommended to improve stethoscope-disinfecting practices in the hospital setting.
Summaries
Stethoscope Contamination Within the Units
The study performed by Whittington et al. (2009) concentrated on the care of patients’ within an
intensive care unit (ICU) of a hospital. This prospective cohort study asked 12 bedside nurses, 10
doctors, nine physical therapists, and two medical students questions on how often they clean their
3. THE DIFFERENCE IN STETHOSCOPE CONTAMINATION 3
stethoscopes. After questioning, a culture was taken from their personal stethoscopes with no
indication of when it was last cleaned. Surprisingly, results from the questionnaire revealed that
91% of nurses cleaned their stethoscopes after each use, 25% of doctors and medical students
sanitized daily or within the last month to six months with 17% reported of never cleaning their
personal stethoscopes. Sixty-seven percent of personal stethoscopes and 95% of ICU bedside
stethoscopes tested positive for pathogenic bacteria; 75% of that group was comprised of MRSA.
Unfortunately, one of the ICU bedside stethoscope’s earpieces tested positive for MRSA
indicating workers were being exposed to pathogens in an unexpected parallel.
Messina et al. (2013) conducted a cross over study within a teaching hospital in Italy that
collected cultures from 35 stethoscopes, 37 headsets, and 27 keyboards distributed among four
different units: first aide, emergency department, ICU, and cardiology. The study was done to
determine the effectiveness of decontamination techniques practiced by the medical staff within
these units. Results showed that keyboards contained the largest colonization of MRSA with
stethoscopes following. Cultures sampled before experimentation revealed stethoscopes harvested
staphylococcus spp. Escherichia Coli, coliform, and MRSA. A significant difference was found
between pre-intervention and post-intervention cleaning. Amongst the four hospital units, first
aide was discovered to be the most contaminated unit, and the ICU was found to be the least
contaminated. The researchers made no recommendations, but concern was stated for the growing
number of older and critical populations in hospitals, which requires strict decontamination
protocols for healthcare staff (Messina et al., 2013).
Tang, Worster, Srigely, and Main (2011) conducted the first study in Canadian
Emergency Departments (ED) to detect the proportion of medical staffs’ personal stethoscopes
that contained S. aureus bacteria or MRSA. Staff were asked consent to participate in the
questionnaire that inquired the frequency of stethoscope cleaning. Cultures were collected from
4. THE DIFFERENCE IN STETHOSCOPE CONTAMINATION 4
stethoscopes without knowledge of the last cleaning. This prospective observational cohort study
consisted of physicians and nurses from three different Canadian EDs. Of the 100 sampled
stethoscopes, 70 cultures had bacterial growth and 30 without growth. Fifty-four cultures
revealed growth of coagulase-negative staphylococcus, 30 cultivated gram-negative cocci and
bacilli, one with staphylococcus aureus, but no results of MRSA found. There was no significant
difference between the bacterial load between physicians and nurses. Reasons found for
inconsistent cleaning of stethoscopes were recorded as: 1) little time 2) lack of initiative and 3)
unavailable cleaning resources.
Contamination by Physicians Fingertips
The Longtin et al. (2014) study focused on the relationship between contamination of
physicans' hands during physical examinations and the transmission of pathogenic bacteria to
stethoscopes. Researchers implemented a prospective study design conducted in two parts. The
first phase examined the hands of a physician with gloves to assess the aerobic colony count
(ACC). The second phase selectively tested MRSA, which required the physician to perform the
physical assessment without gloves, however hand hygiene was allowed afterwards. A total of 489
cultures were collected from the examiners’: fingertips, thenar eminence, hypothenar, and hand
dorsum; two samples were cultured from the diaphragms of stethoscopes and one from the tubing
of each stethoscope following the physical examination. Cultures revealed that the fingertips of the
physician followed by a physical exam had a significant link to the colonization of bacteria on the
diaphragm of stethoscopes. Researchers concluded that the stethoscope should be handled as a
critical assessment tool, compared to the hand’s of the examiner. Researchers suggest further
studies to emphasize the location where bacterial contamination is more likely to originate from,
the patient or the physician.
Disinfection Education
5. THE DIFFERENCE IN STETHOSCOPE CONTAMINATION 5
Uneke et al. (2014) evaluated the effectiveness of an education program established in a
hospital in a Nigerian teaching hospital. The program focused on education the physicians and
nurses on proper sanitization of stethoscopes after each use. The study was performed in a pretest-
posttest design with qualitative and quantitative data. A questionnaire was utilized on the 202
healthcare workers to question about their current routine on stethoscope handling followed by 89
stethoscopes culture collections. Of the 202 workers, 39 were physicians and 163 were nurses.
Pretest results from the questionnaire revealed that 16.7% of physicians cleaned their stethoscope
regularly and 33.3% reported have never cleaned them (Uneke et al., 2014). Before the education
program was initiated, 78.5% of stethoscopes were contaminated with S. aureus and E. Coli.
Thirty-nine percent of nurses disinfected their equipment before and after each use. Posttest results
confirmed that the efforts of the stethoscope disinfection education program lowered
contamination rates by 55%. Results revealed that the efforts of the education training and
marketing strategies on stethoscope disinfection practice had a positive impact on the frequency of
cleaning stethoscopes.
Discussion
Similarities and Limitations
Amongst these studies, Messina et al. (2013), Uneke et al. (2014), and Whittington et al.
(2009) studies recognized a significant difference in the severity of pathogenic bacteria
contamination amongst stethoscopes between doctors and nurses. Uneke et al. (2014), Tang et al.
(2011), and Whittington et al. (2009) used questionnaires to gather data and responses showed the
majority of physicians did not clean their stethoscope once a day, but only once every one to six
months or never cleaned their stethoscope. However, the Uneke et al. (2014) and Whittington et
al. (2009) studies revealed that almost all the nurses who participated stated they sanitized their
stethoscope after each use. Moreover, both studies found the prevalence of stethoscope
6. THE DIFFERENCE IN STETHOSCOPE CONTAMINATION 6
contamination was problematic because the lack of reinforcement for practice. Due to the process
of the studies that used questionnaires, subjects were notified prior to data collection for
permission to participate. Furthermore, researchers had belief that participants tarnished the
integrity of the results for the submission of desirable answers and created a limitation to the
credibility of the results.
Differences and Limitations
The differentiations amongst all the studies discussed are found in the objectives and
location of experimentation, test subjects, and outcomes of the studies. The objective of the Uneke
et al. (2014) study was to establish the effectiveness of stethoscope disinfection education within
the hospital and reinforce the practice through visual aides posted in hospital rooms. The objective
of the Whittington et al. (2009) study was to find an occurrence of poor stethoscope cleaning with
contamination in an intensive care unit in a prospective cohort study approach. Whittington et al.
(2009) had no focus on the affect of stethoscope disinfecting education amongst healthcare
workers. However, the study did recognize the present status of stethoscope contamination on the
ICU unit.
While the studies by Messina et al. (2013), Uneke et al. (2014), and Whittington et al.
(2009) centered on the pathogen culture load, Longtin et al. (2014) concentrated solely on
physicians and the contamination transferred from their fingertips to the diaphragm of a
stethoscope following a physical assessment. According to this study, physicians had a significant
impact on the contamination of stethoscopes and transferred pathogenic bacteria with poor hand
hygiene practice. Location of experimentation varied amongst each study; between various
hospital units and regions around the world. For instance, Messina et al. (2013) concentrated on
the contamination of equipment with the first aide, emergency department, ICU, and cardiology
units of an Italian teaching hospital discovering that keyboards were more contaminated than
7. THE DIFFERENCE IN STETHOSCOPE CONTAMINATION 7
stethoscopes. Uneke et al. (2014) stethoscope disinfection education took place in a teaching
hospital in Nigeria and discovered use of visual reminders to sanitize stethoscopes were effective
in the hospital setting.
The Messina et al. (2013), Uneke et al. (2014), and Whittington et al. (2009) studies found
that physicians were more likely to harvest pathogenic bacteria on their stethoscopes compared to
nurses, therefore physicians were more of a threat to patients in spreading potential pathogens that
cause HAIs. However, Tang et al. (2011) found no significant difference in stethoscope
contamination between physicians and nurses.
Conclusion
Because stethoscope sanitation practice is revealed to be one of the most disregarded
practices, determining whether a physician or nurse is more likely to spread pathogenic bacteria to
patients through their stethoscopes can reinforce the need to improve this practice in the hospital
setting. This is key to understand when examining what risk each work force has on patients to
obtain a HAI. When patients are immunocompromised or exposed to external pathogens as a
result of open wounds, their chances of acquiring an infection increases immensely, ensuing
physicians to be held to a higher standard when using a stethoscope and coming into contact with
patients. While stethoscopes were proven to be viable vectors for pathogenic bacteria, such as, S.
aureus, E. coli, and MRSA, the majority of physicians who participated in the Messina et al.
(2013), Uneke et al. (2014), and Whittington et al. (2009) studies admitted in the questionnaires
they did not sanitize their stethoscope after each use. This holds physicians as a bigger risk than
nurses in the transmission of life-threatening pathogens to patients (Longtin et al., 2014).
8. THE DIFFERENCE IN STETHOSCOPE CONTAMINATION 8
References
Longtin, Y., Schneider, A., Tschopp, C., Renzi, G., Gayet-Ageron, A., Schrenzel, J., & Pittet, D.
(2014). Contamination of stethoscopes and physician’s hands after a physical examination.
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contaminants in hospital settings and progress in disinfecting techniques. BioMed
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Tang, P., Worster, A., Srigely, J., & Main, C. (2011). Examination of staphylococcal stethoscope
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Uneke, C., Nduke, C., Nwakpu, K., Nnabu, R., Ugwuoru, N., & Prasopa-Plaizer, N. (2014).
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