Stethoscopes could play a part in spreading germs

• Study shows stethoscopes have more bacteria than doctors%27 palms
• Researchers encourage doctors to treat stethoscope as extension of their hands and sanitize after seeing each patient
• The study found while doctors%27 fingertips had the most bacteria%2C the stethoscope was not far behind

Doctors' hands touch dozens of patients a day and medical standards require them to sanitize after they examine a patient, but what about their stethoscopes?

With germs from many patients coming into contact with stethoscopes each day, a new study published in the Mayo Clinic Proceedings Thursday, suggests the stethoscope should be subject to the same sanitary procedures as doctors' hands.

Didier Pittet, director of the Infection Control Program at University of Geneva Hospital and lead author on the study, said many times the doctors sanitize their hands with alcohol gel or wash but their stethoscopes are placed back inside their pockets untreated. With recent guidelines by the Society for Healthcare Epidemiology of America indicating medical workers' clothes, jewelry, shoes and stethoscopes can harbor bacteria, he says he hopes the study's findings will put things in motion for stethoscope sanitation to not be just a recommendation but a standard.

"While the doctor's hands are cleaned after each patient, their stethoscope is not, so then they apply the stethoscope to the second patient, and the third, carrying bacteria from each patient's skin," Pittet said.

In the study 83 patients were examined by one of three physicians using sterile gloves and a sterile stethoscope. After the examination the researchers measured the bacteria on the stethoscope diaphragms or the cool part that touches the patient's skin, as well as the stethoscope tube and four regions of the doctors' hands. The study looked at the two things: the bacteria concentration on the physician's hand and stethoscope after examination, and also specifically at the presence of Methicillin Resistant Staphylococcus Aureus (MRSA) or bacteria that is extremely resistant to antibiotics. In 71 of the cases, after the examination, the stethoscope had a higher concentration of bacteria than all parts of the physician's dominant hand except for the fingertips.

According to Pittet the fingertips are the part of the hand that carries the most bacteria.

"We found that the stethoscope was highly contaminated to a level close to the fingertips," Pittet said.

Pittet said that while the stethoscope cannot be blamed for causing infection to spread, it is most likely playing some role in transmitting bacteria.

According to the Centers for Disease Control and Prevention website, hand washing is the top way to stop the spread of bacteria. Pittet, who is an advocate of the World Health Organization hand washing campaign, said doctors should continue to wash hands and look at their stethoscope as an extension, something that should also be sanitized after seeing a patient.

"It's clear cleaning hands with alcohol-based gel is most important to prevent cross contamination with bacteria," Pittet said. "But if your hands are clean and your stethoscope is not, it's counterproductive."