The modern stethoscope consists of four primary components: The earpieces, the headset, the tubing and the chestpiece. The chestpiece consists of a diaphragm and bell, while the headset is essentially a spring that allows the practitioner to pull the eartips apart. The eartips themselves are composed of a soft-sealing material that is designed to remain semi-lubricated for maximum comfort. The tubes are composed of latex or polyvinyl chloride. All of these surfaces are capable of harboring dangerous bacteria.
According to a study published in the journal Mayo Clinic Proceedings, most stethoscopes are laden with bacteria. In some cases, researchers have found antibacterial resistant strains of bacteria, such as MRSA, on the diaphragms of emergency room stethoscopes. Stethoscopes are most frequently seeded with bacteria when they are placed directly on the skin of an affected individual, but the study also revealed that doctors can be vectors of illness as well. Specifically, doctors may harbor dangerous bacteria under their fingernails, and they can easily transplant these bugs onto their stethoscopes.
While doctors are instructed to douse their stethoscope chestpieces in alcohol between each patient, compliance with this guideline is fairly low, especially in the emergency room environment. According to Dr. Didier Pittet, director of the Infection Control Program at the University Hospital of Geneva in Switzerland, anything less than a thorough cleaning of the stethoscope after each examination is unacceptable. Antibiotic-resistant “superbugs” are becoming a concern worldwide, and many organizations are imploring doctors to regularly wash their attire as well. Traditional doctor attire, such as a white coat and tie, can easily transfer bacteria from doctor to patient.
Alarmingly, researchers found that a stethoscope’s tubes can become as bacteria ridden as the diaphragm itself. The number of bacteria present on the tubes increases in conjunction with the amount of bacteria present on the doctor’s fingertips. This is of concern because doctors come in contact with patients on a regular basis, and while doctors are likely to wash their hands, they may not think to sanitize the stethoscope’s tubes. Bacteria can proliferate on the tubes, living off of dead skin and oils, multiplying all the while.
What’s more, as bacteria multiply, they spread across a surface. It’s entirely possible that bacteria from the tubes can spread to a sanitary diaphragm. While alcohol provides a steadfast solution to bacterial proliferation, doctors must be extremely diligent in its application in order to prevent bacteria from spreading from patient to patient.
Doctors can clean stethoscope tubes by scrubbing them with a soft brush impregnated with chlorhexidine, a powerful disinfectant. The brush will remove dirt, lint and oils that bacteria may be living in. The brush will also dislodge bacteria from any pits or cracks that may have developed in the tubing itself. Meanwhile, the chlorhexidine will kill most bacteria.
Following this procedure up with an alcohol wipe will ensure that virtually all of the bacterial present are dead as ethyl alcohol kills by dissolution on contact. Despite the proliferation of bacteria in emergency rooms and on medical diagnostic tools, it is important that patients don’t avoid these resources. Stethoscopes are essential diagnostic tools that can allow doctors to detect serious health issues before they become life threatening.