Aims
The sound environment, or soundscape, of intensive care units (ICUs) can be stressful for patients. Soundscapes are defined as acoustic environments as perceived by people. Single-patient rooms mitigate noise, but may deprive patients of essential auditory cues. This might harm basic psychological needs, such as safety. Experiences, needs and emotions regarding soundscapes of single-patient ICU rooms remain unexplored. We aimed to understand how patients experienced these soundscapes.

Methods
This mixed-methods, single-center study involved semi-structured interviews and questionnaires five days after ICU discharge. Patients experienced the soundscapes during their ICU stay, shared experiences in interviews, and selected one to rate on need fulfilment (with a researcher-developed questionnaire), and emotions (with a validated questionnaire). Using thematic analysis, we analyzed interview transcripts by labelling sound-related experiences, sounds, and emotions.

Findings
We interviewed 26 patients. We labelled 259 sound-related experiences, 264 sounds, and 281 emotions, from which six themes emerged: Orientation through sound; Coping with disruptions; Human auditory presence; Monotony and variation; Associations and hallucinations; Communication behind closed doors. Eight patient-selected experiences involved positive emotions. Need fulfilment scores varied: scores were low for communication-related experiences, but relatively high for those involving human presence.

Conclusions
Our findings demonstrated that experiences with single-patient ICU room soundscapes can be positive or negative. For future implementation of such rooms, three insights merit consideration: positive sounds originating from corridors may be unnecessarily removed; alarms in single-patient rooms serve key supportive functions for patients; there is a lack of accessible and appropriate auditory stimulation. We recommend that these insights are taken into consideration to ensure more positive and restorative ICU stays.

Implications for Clinical Practice
In ICUs, balanced approaches that consider both positive and negative aspects of soundscapes may benefit patients in future interventions for noise mitigation. Diversifying the variety of sounds inside patient rooms could further support well-being.

Sound-driven design is a design practice informed by technology and listening in the multisensory dimension of interaction. An automated content analysis of 20 semi-structured interviews with sound designers, design researchers, engineers and expert users stressed the inherently embodied and situated conceptualisation of sound, and how it relates to their professional activity. The four categories of professionals bring in different designerly orientations towards sound. Listening, as a way of knowing by using sound in interaction, proves to be the red thread between the participants’ semantic models. Overall, the findings contribute to characterise the concept of sound in current design practices, and position the role of nonverbal, yet auditory representations in the design process.

Designing alarms to address the increasing complexity of dynamic and interconnected systems in current socio-technological environments presents multi-faceted design problems that require systematic thinking and a collaborative and holistic approach. To understand the alarm design challenges better, we map out the design space for audible alarms in an applied domain, covering the alarm issues from the designers’ perspective, departing from the functional integrity of alarms, and bringing together the contribution of three major fields of expertise related to audible alarms (systems engineering, information design, and human factors). Three studies based on literature review, field observations, expert interviews, and focus groups are conducted by authors at different European Intensive Care Units. Our findings from these studies result in the definition of the components of audible alarm design, the key considerations for designing audible alarms, and a design framework for audible alarms that systematically integrates input from inter-connected disciplines that all aim for the success of a complex system that heavily relies on alarms.