Stethoscope Contamination: What We Haven’t Learned in 150 Years

By W. Frank Peacock, IV, MD, FACEP, FACC, FESC

Standard of Care?

If you ask a doctor “How often do you clean your stethoscope?” you will likely hear “Oh, in about 30-40% of patient encounters.” If you would then ask “In those 30-40% of encounters, how do you clean your stethoscope?” they will commonly respond “I rub it with an alcohol swab.”

Unfortunately, self-reporting is not very accurate. And although everyone knows that the stethoscope is a strong vector for the transmission of disease, no one wants to admit they do something wrong all day long.

We recently published an observational study in the American Journal of Infection Control. The purpose of this important study was to uncover the facts about real-life stethoscope hygiene. For this investigation, we surreptitiously watched 400 patient-practitioner interactions (the staff didn’t know they were being observed) in high-risk hospital environments like the ER, ICU, and labor and delivery. No (zero) stethoscope hygiene was performed before the patient encounter in 82% of examinations.1 A disgusting finding. And, even when stethoscope cleaning was performed, the quality almost never met the Centers for Disease Control (CDC) cleaning guidelines. In fact, stethoscopes were cleaned consistent with CDC guidance only 4% of the time.1

Unfortunately, the apparent standard of care is to rub dirty contaminated stethoscopes on our patients.  This is because there has never – not in 150 years – been a system that efficiently and reliably provides a clean stethoscope while preserving its function.  This is not a call for a large investment in stethoscope washing, as others have shown that even guideline-compliant stethoscope washing is not effective at eliminating pathogens.  Rather, a disposable, aseptic barrier system for stethoscope diaphragms, one that completely prevents pathogen transmission, presents a strong opportunity for the medical community to improve patient safety.2

1. Boulée D, Kalra S, Haddock A, et al. Contemporary stethoscope cleaning practices: What we haven't learned in 150 years.Am J Infect Control. 2018 Nov 2 Published online 2018 Nov 2.

2. Vasudevan R, Shin JH, Chopyk J, et al. Aseptic Barriers Allow a Clean Contact for Contaminated Stethoscope Diaphragms. Mayo Clin Proc Innov Qual Outcomes. 2020;4(1):21–30. 

W. Frank Peacock IV, MD, FACEP, FACC, FESC is a Professor of Emergency Medicine and Vice Chair for Research in the department of Emergency Medicine at Baylor College of Medicine, in Houston, Texas. With >600 publications, he is a two-time winner of the Best Research Paper of the Year Award from the American College of Emergency Physicians, and he was the 2019 recipient of the Ray Bahr Award for Excellence from the American College of Cardiology.  Finally, he is the founder of Comprehensive Research Associates, LLC, and Emergencies in Medicine, LLC.

Third Hand Vector series spotlights the clinician’s third hand and the risks that contaminated stethoscopes pose to clinicians, patients and healthcare systems. The series features leading experts in infection control, patient care and quality measures raising awareness of the importance of aseptic barriers in reducing transmission of infectious diseases.