Hospital puts noise-reducing strategies to the test

Minimizing the level of noise as much as possible so that patients can rest and heal in comfort is an ongoing challenge for almost all hospitals. That's not easy considering the level of activity going on in a typical hospital nearly around the clock.

University of Michigan (U-M) Health System is experimenting with several ways to eliminate as much noise as possible, including the use of acoustic panels that absorb some sound in the hallways near patient rooms.

Four custom panels, covered in cones and made with sound-absorbing material, were installed for three days in the walls and ceilings of a cardiovascular care unit. So far, the panels slightly reduced decibels from 60 to 57 during a pilot study in which they were placed strategically in the hallways near patient rooms.

Though the decrease appears slight, it is meaningful, say authors of the study. The modest drop in sound is recognizable to the human ear and is comparable to a drop in noise generated by a car slowing from 80 mph to 60 mph, according to the authors.

"In hospital environments where noise levels are often double what they should be, according to the World Health Organization's standard decibel guidelines for patient rooms, the difference is significant," says Majtaba Navvab, Ph.D., associate professor of architecture and design at the Taubman College of Architecture and Urban Planning at the University of Michigan.

Navvab is partnering with U-M Architecture, Engineering and Construction on room acoustic research, and collaborated with physicians Peter M. Farrehi, M.D., a cardiologist at the U-M Health System, and Brahmajee K. Nallamothu, M.D., on the noise-reduction study.

The architectural design could complement ongoing strategies for addressing noise, says Farrehi. "The panels help diffuse sound, rather than attempt to eliminate the sounds generated in a modern hospital environment."

The acoustic sound panels are one of several actions the hospital and its affiliated health centers are taking to reduce noise, enhance the patient experience and to improve working conditions for employees.

Other steps the health care system is taking include:

• Providing complementary ear buds, headphones and earplugs for patients and their families.
• Keeping hallway conversation to a minimum, especially at night.
• Establishing quiet hours in all inpatient areas.
• Encouraging patients and staff to respect others by turning down the volume on cellphones, televisions, radios, pagers and other devices.
• Minimizing cellphone conversations in hospital hallways and waiting rooms and encouraging others to do the same.
• Coordinating care to reduce unnecessary entry into patient rooms during quiet hours.
• Reminding staff to be quiet in the patient care setting.
• Providing a "white noise" TV channel in all patient rooms.
• Wearing soft-sole shoes to minimize hallway noise.
• Placing work orders through a dedicated system to have noisy carts, doors and other items repaired.
• Scheduling floor cleaning times that don't conflict with nighttime resting hours.
• Testing meters that indicate sound levels in some patient rooms.

Research reveals that a noisy environment makes patients unhappy, but it is unhealthy, too, causing spikes in blood pressure and interfering with wound healing and pain management.

Noise also affects staff who work with and near patients. Previous studies have shown a direct correlation between sound decibel levels in work environments and employee blood pressure levels and heart rates.

Hospital noise is ranked low on the national Hospital Consumer Assessment of Healthcare Providers and Systems, and those scores can impact hospital reimbursement. Patients who are dissatisfied with the noise in their rooms are often significantly less satisfied with their overall hospital experience.