Solving the problem of sleep in hospitals

— "My concern is that we just don't forget about the other things that are problematic," she said.

An earbud, she said, wouldn't change the source of the sound or how hospitals are designed. For example, hospitals often have hard, resonant floors that echo and propagate noise. To combat this, some have incorporated new materials into walls and ceiling tiles that can dampen sound but that are still hygienic and cleanable, Ryherd said.

"Hospitals do seem to be getting noisier as time goes on," she added, but alarms are hardly the only noise around. Between the bustle of people, carts rolling down the hallway and even the occasional helicopter, there's a lot going on in a dense space.

But medical devices do have certain acoustic features -- like their pitch, loudness and repetitiveness, she said -- that make them stand out from the din in order to alert doctors and nurses when something is amiss.

Louder noise in the hospital may have led to an arms race of even louder alarms, all clamoring to be heard over each other. Some researchers call this an "acoustic feedback loop."

The problem, Schelesinger said, is that many alarms are useless.

In one study of a single intensive care unit, for example, only 15% of alarms were considered "clinically relevant." About 40% were just plain wrong. Some of these noises only end up alarming the patients, Schlesinger said; doctors may know which noises require them to spring into action, but patients may think they're being ignored.

The end result, Schlesinger said, is that noisy, restless nights in the hospital can be disorienting for patients. This may especially be the case in the intensive care unit (ICU), where some of the most serious patients are monitored but which also happens to be one of the louder places in the hospital, he said.

Research has linked poor sleep with delirium in the ICU, higher blood pressure and worse mental health outcomes. It may also increase sensitivity to pain.

The federal Centers for Medicare and Medicaid Services asks about nighttime quietness on its patient satisfaction survey. This may give hospitals a financial incentive to turn down the volume, as survey scores are tied to reimbursements.

"You can't take away patient monitoring -- that's critical -- but it's not really working for the patients," Ryherd said. "I can't think of too many people I've talked to that have enjoyed the sound environment of the hospital."