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2004) and others finding that the effect depends on individ- ual preference and seems to impact short-term memory and mental efficiency (Park and Song, 1994; Murthy et al., 1995).
The Impact of Hospital Soundscapes on Patients
Hospital soundscapes affect patients quite differently from staff because patients in hospital are present around the clock. Patients are a vulnerable population, often anxious about their medical situation and recovering from illnesses or sur- gical procedures. Furthermore, although staff members have some modest amount of control over the noise produced in a unit, patients have almost no such control. This negatively affects the patient experience with the hospital environment.
A host of potential reactions have been investigated over the years, including sleep disturbance, physiological responses (e.g., cardiovascular response, hospital stay, pain manage- ment, wound healing, other physiological reactions), and psychological reactions (e.g., general perception, delirium, satisfaction). Results generally show that hospital sound- scapes impact patients.
The most-studied impact of hospital noise on patients con- siders the interaction of noise and sleep. Disrupted sleep is known to relate to blood pressure increases, weight gain, heart disease, pain, stress, and inflammation. A study by Gabor et al. (2003) was among the first to directly measure sleep stage and correlate it with noise. Subjects were both patients on mechanical ventilators in an intensive care unit and healthy subjects sleeping in the unit. For healthy subjects, the majority of arousals from sleep were correlated with the sound peaks. For ventilated patients, only about 20% of the arousals were related to sound. Overall, most of the causes of sleep arousals were unknown and surveys the following day were unlikely to accurately identify noise sources caus- ing arousals. The Sound Sleep Study reported by Buxton et al. (2012) was conducted in sleep labs using recorded sounds typical in hospitals and found that as sounds got louder, they were more likely to cause sleep arousals, with alarms and ringing phones the most likely culprits. Again, subjects were unable to identify the noise sources that caused them to awaken. Persson Waye et al. (2013) found that for subjects exposed to intensive care unit noise, sleep was more frag- mented, with less slow-wave sleep, more arousals and more time awake compared with a reference night.
Although these studies suggest that hospital soundscapes impact sleep, the repercussions remain unclear. We don’t know, for instance, whether poor sleep in hospitals causes
extended stays. We do know that patients do not view the hospital as a place where it is easy to fall asleep. The Hospital Consumer Assessment of Healthcare Providers and Systems survey (HCAHPS), mandated in the United States since 2008, has a single question about acoustics, asking patients to rate the area around their room as always, usually, sometimes, or never quiet at night. This was routinely the question receiv- ing the lowest patient score on the survey until recently when the survey was changed. Locke and Pope (2017) compared the responses of patients to the noise question in 2010 and 2014. They found a drop in the fraction of patients regarding their room as always quiet at night from 2010 to 2014 and an increase in the fraction saying their room was never quiet at night, results trending in the wrong direction.
In addition to sleep studies, there has been some research on other physiological impacts of sound on patients. For instance, Hsu et al. (2012) studied patient heart rate, respi- ration rate, systolic and diastolic blood pressure, and blood oxygen saturation levels as a function of sound pressure level. This study found correlations between increasing levels and increases in physiological measures except for blood oxygen saturation, which trended downward with increasing level.
Studies of the psychological impacts of hospital sounds on patients have focused on the sense of well-being and on the impact of music. For example, Cunha and Silva (2015) had patients take two surveys: the Environmental Comfort Questionnaire (EMQ) to measure noise perception and the Positive and Negative Affect Schedule (PANAS) to measure emotion. They found significant correlations between noise levels and perceptions of well-being, with higher noise levels leading to a reduced sense of well-being. A more recent study by Bliefnick (2018) also utilized the PANAS and found that subjects listening to hospital soundscapes for 30 minutes dis- played decreased moods.
There are interesting studies on the impact of music on patients. For instance, McClurkin and Smith (2016) stud- ied the impact of music on preoperative patients. They determined that listening to as little as 15 minutes of music before surgery reduced anxiety. There are companies that are producing soothing sound products for hospitals and clinics to use.
Studies Using Soundscape Analytical Approaches
One of the earliest efforts to use analytical techniques devel- oped for psychology on hospitals was reported by Mourshed
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