A challenge to the evidence behind noise guidelines for UK hospitals

BACKGROUND

Teams assessing hospital noise against international guidelines regularly find that noise exceeds perceived safe levels in clinical settings. The care of sick people may be inherently noisy but recent efforts to tackle the problem propose a wider scope to identify sources and qualities of noise as well as more precision with noise recording.

AIMS

We sought to challenge the scientific evidence cited in the four major documents pertaining to hospital noise in the UK to clarify if evidence of harm from noise included in guidelines is available, contemporary and of high quality.

METHODS

Our team of hearing-health clinicians, acoustic scientists and acoustic engineers have conducted a narrative scoping review focused on critically appraising four of the most cited guidelines against which noise is measured in healthcare settings in the UK.

RESULTS

There is a lack of high-quality evidence for commonly accepted consequences of noise cited in current guidelines.

CONCLUSIONS

The current evidence base for noise guidelines in a healthcare setting is largely based on subjective heterogeneous and inconclusive research. Whilst reduced noise is not disputed as potentially beneficial for patient care, further hypothesis-driven research and interventions assessing the benefits or outcomes of any such intervention should be sought to produce high-quality evidence of relevance on the clinical coalface.

The Intelligibility of the Reversed-Stethoscope Technique in Age-Related Hearing Loss

Background

This study evaluated the effectiveness of the reverse stethoscope technique in improving speech intelligibility. In this technique, a clinician places the earpieces of their stethoscope into the ears of a hearing-impaired patient and speaks into the chest piece.

Methods

The International Speech Test Signal was presented to four Littman® stethoscope models and a Pocketalker® personal voice amplifier using an Audioscan® hearing instrument test box. The acoustic outputs of the stethoscopes and voice amplifier were measured across the frequency spectrum of speech. The Speech Intelligibility Index of the resulting speech was calculated for natural speech and for each device in relation to 10 standardized hearing losses representing the population of older adults.

Results

For each of the 10 hearing losses, the speech signal emitted by the stethoscopes was quieter and yielded lower speech intelligibility scores than regular speech. In contrast, the voice amplifier provided mid- and high-frequency amplification and improved speech intelligibility scores for all but the mildest hearing losses.

Conclusions

The reverse stethoscope technique worsens the clarity of speech and should not be used with older, hearing-impaired patients. Instead, clinicians should use regular speech or, preferably, personal voice amplifiers.

Intelligibility of medically related sentences in quiet, speech-shaped noise, and hospital noise

Noise in healthcare settings, such as hospitals, often exceeds levels recommended by health organizations. Although researchers and medical professionals have raised concerns about the effect of these noise levels on spoken communication, objective measures of behavioral intelligibility in hospital noise are lacking. Further, no studies of intelligibility in hospital noise used medically relevant terminology, which may differentially impact intelligibility compared to standard terminology in speech perception research and is essential for ensuring ecological validity. Here, intelligibility was measured using online testing for 69 young adult listeners in three listening conditions (i.e., quiet, speech-shaped noise, and hospital noise: 23 listeners per condition) for four sentence types. Three sentence types included medical terminology with varied lexical frequency and familiarity characteristics. A final sentence set included non-medically related sentences. Results showed that intelligibility was negatively impacted by both noise types with no significant difference between the hospital and speech-shaped noise. Medically related sentences were not less intelligible overall, but word recognition accuracy was significantly positively correlated with both lexical frequency and familiarity. These results support the need for continued research on how noise levels in healthcare settings in concert with less familiar medical terminology impact communications and ultimately health outcomes.

Impact of sound levels on physiological and consciousness state of cardiovascular patients

BACKGROUND

Patients treated in intensive care units (ICUs) experience life-threatening medical conditions but some external factors in ICUs do not help or even adversely affect and complicate their evolution. Among others, such factors include noise pollution due to alarms and medical clinical equipment, as well as the activities of the health care personnel themselves.

AIM

This study aimed to evaluate the influence of elevated sound levels on physiological variables and the consciousness state of patients treated in a cardiovascular area in an ICU.

DESIGN

A longitudinal study with several observations was carried out during 1 month in the cardiovascular area of an ICU of a third-level hospital in southern Spain.

METHODS

Sound levels were monitored in different work shifts and patients' physiological data and consciousness status were recorded. Generalized additive mixed models (GAMMs) were developed to detect the variability of the sound levels together with the vital parameters of the patients in the ICU.

RESULTS

Thirty-eight patients were included. The mean sound level was 54.09 dBA. The GAMM sound levels analysis showed a significant increase in sound levels from 4:30 p.m. to 8:00 p.m. (1.83 dBA; P < .001) and 8:00 p.m. to 11:30 p.m. (3.06 dBA; P < .001). An increase in heart rate (3.66 bpm; P < .001), respiratory rate (2.62 rpm; P < .001) and the Glasgow Coma Scale (0.50 units; P = .002) was detected during the 4:30 p.m.-8:30 p.m.

PERIOD

CONCLUSIONS

Elevated sound levels in cardiovascular ICUs seem to influence positively the physiological and consciousness status of patients. Given the importance of the findings for patient safety, future intervention studies are recommended.

RELEVANCE TO CLINICAL PRACTICE

The finding of this study could translate into structural changes in ICU facilities, as well as the development of clinical practice guidelines that influence the behaviour of health care professionals.

Achieving Noise Reduction With a Novel Lower Limb External Mechanical Compression System

Hospitals are one of the noisiest public environments in the United States, and hospital noise is associated with disrupted sleep. This study provides insights into the noise levels produced by three commonly used medical devices for mechanical deep vein thrombosis prophylaxis: the VenaFlow Elite System, the Kendall SCD Compression System, and the ArjoHuntleigh Flowtron. Noise levels produced were compared with a novel device, the RF Health MAC™ system, which was designed to provide improved comfort and noise reduction. Results suggest that future innovation in mechanical deep vein thrombosis prophylaxis should include efforts to reduce noise during operation.

Assessing the benefit of acoustic beamforming for listeners with aphasia using modified psychoacoustic methods

Acoustic beamforming has been shown to improve identification of target speech in noisy listening environments for individuals with sensorineural hearing loss. This study examined whether beamforming would provide a similar benefit for individuals with aphasia (acquired neurological language impairment). The benefit of beamforming was examined for persons with aphasia (PWA) and age- and hearing-matched controls in both a speech masking condition and a speech-shaped, speech-modulated noise masking condition. Performance was measured when natural spatial cues were provided, as well as when the target speech level was enhanced via a single-channel beamformer. Because typical psychoacoustic methods may present substantial experimental confounds for PWA, clinically guided modifications of experimental procedures were determined individually for each PWA participant. Results indicated that the beamformer provided a significant overall benefit to listeners. On an individual level, both PWA and controls who exhibited poorer performance on the speech masking condition with spatial cues benefited from the beamformer, while those who achieved better performance with spatial cues did not. All participants benefited from the beamformer in the noise masking condition. The findings suggest that a spatially tuned hearing aid may be beneficial for older listeners with relatively mild hearing loss who have difficulty taking advantage of spatial cues.

Longitudinal Relationships Between Decline in Speech-in-Noise Recognition Ability and Cognitive Functioning: The Longitudinal Aging Study Amsterdam

Purpose Various directional hypotheses for the observed links between aging, hearing, and cognition have been proposed: (a) cognitive load on perception hypothesis, (b) information degradation hypothesis, (c) sensory deprivation hypothesis, and (d) common cause hypothesis. Supporting evidence for all 4 hypotheses has been reported. No studies have modeled the corresponding 4 causal pathways into 1 single model, which would be required to evidence that multiple directional hypotheses apply. The aim of the current study was to tease out which pathways apply for 5 different cognitive measures. Method Data from 1,029 respondents of the Longitudinal Aging Study Amsterdam were used spanning a maximum follow-up of 7 years (3 measurements). Speech-in-noise recognition ability (digit triplet speech-in-noise test) was included as a measure of auditory function. Cognitive measures included global cognitive functioning, fluid intelligence, information processing speed, and verbal memory (immediate recall and retention). Bivariate dual change score modeling was used to model the causal pathways between hearing, cognition, and baseline age. Results For information processing speed, global cognitive functioning, fluid intelligence, and memory-immediate recall, all pathways except for the sensory deprivation pathway were supported. For memory-retention, only the common cause and the sensory deprivation pathways were supported. Conclusions Causal pathways corresponding to all 4 hypotheses were supported. Support for the common cause hypothesis, the information degradation hypothesis, and the cognitive load on perception hypotheses was found for 4 of 5 cognitive measures. This was unexpected in some cases (e.g., support for the information degradation pathway for cognitive measures that do not rely on auditory stimuli). The sensory deprivation pathway that emerged for memory-retention might point toward processes related to early stages of dementia. In summary, the results show that the links between decline in auditory function, cognition, and aging are complex and most likely are captured by pathways belonging to various directional hypotheses.

Effects of Acquired Aphasia on the Recognition of Speech Under Energetic and Informational Masking Conditions

Persons with aphasia (PWA) often report difficulty understanding spoken language in noisy environments that require listeners to identify and selectively attend to target speech while ignoring competing background sounds or “maskers.” This study compared the performance of PWA and age-matched healthy controls (HC) on a masked speech identification task and examined the consequences of different types of masking on performance. Twelve PWA and 12 age-matched HC completed a speech identification task comprising three conditions designed to differentiate between the effects of energetic and informational masking on receptive speech processing. The target and masker speech materials were taken from a closed-set matrix-style corpus, and a forced-choice word identification task was used. Target and maskers were spatially separated from one another in order to simulate real-world listening environments and allow listeners to make use of binaural cues for source segregation. Individualized frequency-specific gain was applied to compensate for the effects of hearing loss. Although both groups showed similar susceptibility to the effects of energetic masking, PWA were more susceptible than age-matched HC to the effects of informational masking. Results indicate that this increased susceptibility cannot be attributed to age, hearing loss, or comprehension deficits and is therefore a consequence of acquired cognitive-linguistic impairments associated with aphasia. This finding suggests that aphasia may result in increased difficulty segregating target speech from masker speech, which in turn may have implications for the ability of PWA to comprehend target speech in multitalker environments, such as restaurants, family gatherings, and other everyday situations.

The Physiologic and Psychophysical Consequences of Severe-to-Profound Hearing Loss

Substantial loss of cochlear function is required to elevate pure-tone thresholds to the severe hearing loss range; yet, individuals with severe or profound hearing loss continue to rely on hearing for communication. Despite the impairment, sufficient information is encoded at the periphery to make acoustic hearing a viable option. However, the probability of significant cochlear and/or neural damage associated with the loss has consequences for sound perception and speech recognition. These consequences include degraded frequency selectivity, which can be assessed with tests including psychoacoustic tuning curves and broadband rippled stimuli. Because speech recognition depends on the ability to resolve frequency detail, a listener with severe hearing loss is likely to have impaired communication in both quiet and noisy environments. However, the extent of the impairment varies widely among individuals. A better understanding of the fundamental abilities of listeners with severe and profound hearing loss and the consequences of those abilities for communication can support directed treatment options in this population.

Impact of Hearing Loss on Patient–Provider Communication Among Hospitalized Patients: A Systematic Review

Age-related hearing loss is a highly prevalent chronic condition in older adults, but hearing loss is rarely accounted for in patient–provider communication studies. This systematic review synthesizes current evidence on the impact of age-related hearing loss on patient–provider communication in hospitalized older adults. Five databases were queried to identify original research that examined patient–provider communication in older adults with hearing loss in an inpatient setting. Of 1053 studies, 13 were included in the final review. All studies reported an adverse effect of hearing loss on patient–provider communication. Among studies that evaluated an intervention to improve communication in older adults with hearing loss, simple interventions such as low-cost voice amplifiers were found to improve communication. An understanding of the effect of hearing loss on patient–provider communication and strategies to mitigate the impact are needed in order to provide safe, quality, patient-centered care to older adults with hearing loss.

Noise Reduction in Progressive Care Units

Uncontrolled noise in the hospital setting can have a negative physiological and psychological impact on patients and nurses. To reduce unit noise levels and create a quiet patient and nurse experience, an evidence-based practice project was conducted in 4 progressive care units in a community hospital. The Quiet Time Bundle implementation improved patient satisfaction and patient and nurse perceptions of noise even though the decrease in noise levels may not be discernible.

Hearing and Health Outcomes: Recognizing and Addressing Hearing Loss in Hospitalized Older Adults

As age increases, the prevalence of hearing loss significantly increases, reaching up to 89% of those 80 years and older. Hearing loss in older patients is often unrecognized and its consequences are often underappreciated. Hearing loss can interfere with the ability to exchange important health information and to participate in health care decision-making. Hearing loss during hospitalization increases the risk of misdiagnosis. There is a lack of empirical data regarding prevalence and recognition of hearing loss in hospitalized older adults. In this article, we describe a variety of negative outcomes that may result when older inpatients are functioning with unrecognized hearing loss.

Exploring the effect of sound and music on health in hospital settings: A narrative review

BACKGROUND

Sound in hospital space has traditionally been considered in negative terms as both intrusive and unwanted, and based mainly on sound levels. However, sound level is only one aspect of the soundscape. There is strong evidence that exploring the positive aspect of sound in a hospital context can evoke positive feelings in both patients and nurses. Music psychology studies have also shown that music intervention in health care can have a positive effect on patient's emotions and recuperating processes. In this way, hospital spaces have the potential to reduce anxiety and stress, and make patients feel comfortable and secure. This paper describes a review of the literature exploring sound perception and its effect on health care.

DATA SOURCES AND REVIEW METHODS

This review sorted the literature and main issues into themes concerning sound in health care spaces; sound, stress and health; positive soundscape; psychological perspective of music and emotion; music as a complementary medicine for improving health care; contradicting arguments concerning the use of music in health care; and implications for clinical practice. Using Web of Science, PubMed, Scopus, ProQuest Central, MEDLINE, and Google, a literature search on sound levels, sound sources and the impression of a soundscape was conducted. The review focused on the role and use of music on health care in clinical environments. In addition, other pertinent related materials in shaping the understanding of the field were retrieved, scanned and added into this review.

RESULTS

The result indicated that not all noises give a negative impression within healthcare soundscapes. Listening to soothing music was shown to reduce stress, blood pressure and post-operative trauma when compared to silence. Much of the sound conveys meaningful information that is positive for both patients and nurses, in terms of soft wind, bird twitter, and ocean sounds.

CONCLUSIONS

Music perception was demonstrated to bring about positive change in patient-reported outcomes such as eliciting positive emotion, and decreasing the levels of stressful conditions. Whilst sound holds both negative and positive aspects of the hospital ecosystem and may be stressful, it also possesses a soothing quality that induces positive feelings in patients. Conceptualizing the nature of sound in the hospital context as a soundscape, rather than merely noise can permit a subtler and socially useful understanding of the role of sound and music in the hospital setting, thereby creating a means for improving the hospital experience for patients and nurses.

Noise Affects Performance on the Montreal Cognitive Assessment

L’objectif était d’investiguer l’impact de la présence d’un bruit de fond sur la performance au Montreal Cognitive Assessment (MoCA). Deux versions du MoCA ont été administrées, utilisant écouteurs, avec des niveaux bas et élevés de bruit de fond à deux groupes de personnes âgées (un groupe présentant une audition cliniquement normale, le second présentant une perte d’audition) ainsi qu’à un groupe de jeunes adultes. Les niveaux d’intensité utilisés pour présenter la parole et le bruit étaient personnalisés en fonction des habiletés des participants présentant une perte de l’ouïe, et ce en vue de créer un niveau de difficulté uniforme à travers les participants dans la condition de bruit plus élevé. Les deux groupes de personnes âgées ont obtenu des scores plus faibles au MoCA en comparaison aux jeunes adultes. Il est également important de souligner que tous les participants ont obtenu des scores plus faibles au MoCA lorsque le test était administré dans un contexte de bruit élevé (M = 22,7/30), en comparaison à un contexte de bruit faible (M = 25,7/30, p < .001). Ces résultats suggèrent que le bruit de fond présent dans un contexte d’évaluation devrait être pris en considération au moment de l’administration de tests cognitifs ainsi que dans l’interprétation des résultats, en particulier lors de l’essai des adultes plus âgés.

Acoustic assessment of speech privacy curtains in two nursing units

Hospitals have complex soundscapes that create challenges to patient care. Extraneous noise and high reverberation rates impair speech intelligibility, which leads to raised voices. In an unintended spiral, the increasing noise may result in diminished speech privacy, as people speak loudly to be heard over the din. The products available to improve hospital soundscapes include construction materials that absorb sound (acoustic ceiling tiles, carpet, wall insulation) and reduce reverberation rates. Enhanced privacy curtains are now available and offer potential for a relatively simple way to improve speech privacy and speech intelligibility by absorbing sound at the hospital patient's bedside. Acoustic assessments were performed over 2 days on two nursing units with a similar design in the same hospital. One unit was built with the 1970s' standard hospital construction and the other was newly refurbished (2013) with sound-absorbing features. In addition, we determined the effect of an enhanced privacy curtain versus standard privacy curtains using acoustic measures of speech privacy and speech intelligibility indexes. Privacy curtains provided auditory protection for the patients. In general, that protection was increased by the use of enhanced privacy curtains. On an average, the enhanced curtain improved sound absorption from 20% to 30%; however, there was considerable variability, depending on the configuration of the rooms tested. Enhanced privacy curtains provide measureable improvement to the acoustics of patient rooms but cannot overcome larger acoustic design issues. To shorten reverberation time, additional absorption, and compact and more fragmented nursing unit floor plate shapes should be considered.

The Effectiveness of Measures Aimed at Noise Reduction in an Intensive Care Unit

Noise is a significant problem for both hospitalized patients and health care workers. This study aimed to determine the effectiveness of noise reduction strategies in an intensive care unit. Noise was measured in two phases. In the first phase, the unit’s present level of noise was established over 3 weeks between January 1, 2012, and February 1, 2012. During the month following initial measurements, noise reduction interventions, including staff education and physical space arrangement, were initiated, and device alarms were checked. The second phase of measurement was conducted during another 3-week period (between June 1, 2012, and July 1, 2012). The noise levels before and after noise reduction interventions were calculated as 67.6 dB-A and 56 dB-A; the difference between the two levels was statistically significant ( p < .05). The interventions were effective in reducing noise in intensive care units; the interventions are relatively easy and low cost.

Nurse and patient interaction behaviors' effects on nursing care quality for mechanically ventilated older adults in the ICU

The study purposes were to (a) describe interaction behaviors and factors that may effect communication and (b) explore associations between interaction behaviors and nursing care quality indicators among 38 mechanically ventilated patients (age ≥60 years) and their intensive care unit nurses (n = 24). Behaviors were measured by rating videorecorded observations from the Study of Patient-Nurse Effectiveness with Communication Strategies (SPEACS). Characteristics and quality indicators were obtained from the SPEACS dataset and medical chart abstraction. All positive behaviors occurred at least once. Significant (p < 0.05) associations were observed between (a) positive nurse and positive patient behaviors, (b) patient unaided augmentative and alternative communication (AAC) strategies and positive nurse behaviors, (c) individual patient unaided AAC strategies and individual nurse positive behaviors, (d) positive nurse behaviors and pain management, and (e) positive patient behaviors and sedation level. Findings provide evidence that nurse and patient behaviors effect communication and may be associated with nursing care quality.

Adaptation of a communication interaction behavior instrument for use in mechanically ventilated, nonvocal older adults

BACKGROUND

Valid and reliable instruments are needed to measure communication interaction behaviors between nurses and mechanically ventilated intensive care unit patients who are without oral speech.

OBJECTIVES

The aim of this study was to refine and evaluate preliminary validity and reliability of a Communication Interaction Behavior Instrument (CIBI) adapted for use with mechanically ventilated, nonvocal patients in the intensive care unit.

METHODS

Raters observed nurse-patient communication interactions using a checklist of nurse and patient behaviors, categorized as positive and negative behaviors. Three-minute video-recorded observations of five mechanically ventilated adults (<60 years old) in the intensive care unit and their nurses were used to establish preliminary interrater reliability and confirm appropriateness of definitions (four observations per dyad, n = 20). On the basis of expert input and reliability results, the behaviors and item definitions on the CIBI were revised. The revised tool was then tested in a larger sample of 38 mechanically ventilated intensive care patients (> 60 years old) and their nurses (four observations per dyad, n = 152) to determine interrater reliability.

RESULTS

For preliminary testing, percent agreement for individual items ranged from 60% to 100% for nurse behaviors and 20% to 100% for patient behaviors across the five pilot cases. On the basis of these results, 11 definitions were modified and four items were dropped. Using the revised 29-item instrument, percent agreement improved for nurse behaviors (73%-100%) and patient behaviors (68%-100%). Kappa coefficients ranged from 0.13 to 1.00, with lower coefficients for patient behaviors.

CONCLUSION

Preliminary results suggest that the revised CIBI has good face validity and shows good interrater reliability for many of the behaviors, but further refinement is needed. The use of dual raters with adjudication of discrepancies is the recommended method of administration for the revised CIBI.